Background: In obesity, significant hormonal and inflammatory changes create a mitogenic microenvironment and promote tumorigenesis. Obesity at time of breast cancer (BC) diagnosis and following treatment is associated with poorer BC survival, particularly for hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) BC. Furthermore, weight gain is a common side-effect of the adjuvant endocrine therapy necessary to decrease the risk of recurrence. Obesity disproportionately affects Black women 57.2% vs. 38.2% Non-Hispanic White women, with central obesity and higher adiposity being associated with higher all-cause and breast cancer-specific mortality among Black BC survivors. Previous reports have indicated that a 5% weight loss is sufficient to reverse the metabolic disarray induced by obesity. Tirzepatide, an analogue of gastric inhibitory polypeptide (GIP), and a dual GIP and GLP-1 Receptor Agonist, a first-in-class new drug, demonstrated substantial and sustained reductions in body weight (up to 21%) and reversal of cardiometabolic disarray in a 72-week weight loss clinical trial. We hypothesize that tirzepatide will result in ≥5% in body weight reduction in obese patients during the adjuvant treatment of HR+/Her2- BC. Trial Design: This is a single arm, phase II, non-randomized trial for the weekly administration of tirzepatide for two years of weight loss intervention during the adjuvant treatment of early-stage HR+/HER2- BC. Patients fitting the obesity body mass index (BMI) criteria, BMI ≥30 kg/m2 or ≥27 kg/m2 with at least one weight related comorbidity will be eligible. This study will enroll 20 Black and 20 Non-Black BC patients at the Rutgers Cancer Institute/RWJ Barnabas Health System. This will enrich the cohort of trial participants with the Black population that has an established disparity in HR+/Her2- breast cancer and obesity related outcomes. Specific Aims: The primary endpoint is to determine how many patients achieve a 5% or more body weight reduction at the end of study treatment with tirzepatide. Secondary endpoints include safety and tolerability and to determine the feasibility of using tirzepatide for weight loss intervention during the adjuvant treatment for HR+/Her2- BC, based on discontinuation rates. Changes in different obesity measurements such as BMI, body fat distribution via Waist/Hip Ratio (WHR) and waist circumference will be assessed. 3-year invasive disease-free survival, 3-year distant relapse-free survival will be determined and changes in obesity related metabolic markers and ctDNA will be assessed. Exploratory objectives investigating adipokines and their receptors, metabolomic pathways and immune cell metabolism will be conducted. Statistical Methods: Our outcome of interest will be the percentage of patients with a weight loss of more than 5 percent. We plan to carry out a 5 percent level one-sided test of proportions in a single-arm study. With 40 patients, we have 80 percent power to detect an increase from 0.42 (the derived estimated proportion with weight loss exceeding 5 percent with standard therapy) to 0.617 in patients treated with tirzepatide. Results: This is a clinical trial in progress with IRB approval (approval number: Pro2024000646) and can be found on clinicaltrials.gov. Results will be presented at a future date. Conclusion: Successful outcomes from this trial would demonstrate that tirzepatide administration can lead to substantial weight loss and significant improvement in cardiometabolic health in obese BC patients, and may help reduce the risk of BC recurrence during the adjuvant treatment for HR+/HER2- breast cancer. The exploratory objectives may provide biological insights and potential targets for treatment. Grant Support - Ludwig Institute for Cancer Research/The Hilton Foundation. Contact information: Coral Omene, MD/PhD. email: co273@cinj.rutgers.edu. Citation Format: Coral Omene, Mridula George, Maria Kowzun, Shicha Kumar, Firas Eladoumikdachi, Lindsay Potdevin, Jonathan Smith, Kathleen Toomey, George Raptis, Lori Schleischer, Trishala Meghal, Gerardo Capo, Dirk Moore, Eileen White, Joshua Rabinowitz, Lydia Lynch, Yibin Kang, Kellen Olszewski, Adana Llanos, Elisa Bandera, Anita Kinney, Deborah Toppmeyer, Shridar Ganesan. FITWISE: Feasibility study of tirzepatide for weight loss intervention in early stage hormone receptor positive/HER2 negative breast cancer [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2024; 2024 Dec 10-13; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(12 Suppl):Abstract nr P2-08-25.

441 Background: Data suggest that patients with tumors with microsatellite instability (MSI-H), EBV expression, or positive PD-L1 expression can benefit from immunotherapy. This trial evaluated PD-1 immunotherapy in this subset of patients with operable gastric cancer. Methods: We present results of a phase 2 multi-institutional clinical trial (NCT03257163). Patients with cT2-T4, N0-N3, M0 gastric adenocarcinoma with MSI-H, PDL1 CPS > 1%, or EBV+ were included. Patients received 2 cycles preop pembrolizumab 200 mg IV q3 weeks followed by surgery. Pembrolizumab was given for 16 additional cycles postoperatively, concurrently with adjuvant chemoradiation (45 Gy) and 5 cycles of capecitabine (825 mg/m2 days 1-14 during cycles 3, 6 and 7; 625 mg/m2 BID days 1-14 during cycles 4 and 5 with radiation). Patients were defined as evaluable if they received > one cycle of postop pembrolizumab. Primary endpoint is DFS, powered to detect 3-yr DFS of 70% with 89% power. Results: All enrolled patients received two cycles of pembrolizumab preoperatively (n=45). Eight patients did not undergo surgery (1 due to frailty, 2 with distant progression on preoperative imaging, 2 with peritoneal disease on surgical exploration and 3 with locally advanced, unresectable tumors). Six patients did not receive adjuvant therapy (2 due to surgical complications, 2 for failure to thrive, 1 refusal and 1 pending adjuvant therapy). 31 patients received adjuvant therapy and are included in the predetermined, evaluable analytic cohort. These 31 patients had a median age of 67 years (range 44 – 85) with 22.6% Hispanic, 29.0% Asian, 25.8% Black and 25.8% White. Median follow-up was 31.1 months (range 3.45-63.8). In these patients, 14 (45.2%) had MSI-H, 2 (6.5%) EBV+, and 29 (93.5%) had PDL1 expression >1% tumors. Most tumors were advanced stage with 81% ≥ cT3 and 58% cN+. In the 31 evaluable patients, the 3-year DFS was 79.4%; 3-year OS was 78.9%. For MSI-H patients, 3-year DFS was 81.8%. For patients with MSS/PD-L1+ tumors, 3-year DFS was 77.8%. For the 45-patient cohort, 3-year DFS was 70%; 3-year OS was 65%. Three patients had pCR, two with MSI-H tumors and one with PD-L1 CPS of 4%. Downstaging occurred in 62.2% of patients, and 40% of surgical specimens had pT0/T1 tumors consistent with significant pathologic responses. Conclusions: A biomarker-driven preoperative treatment strategy for MSI-H, EBV+, and MSS/PDL1+ operable gastric adenocarcinoma patients is promising and warrants additional evaluation. This treatment strategy is novel and effective, and it incorporates immune checkpoint immunotherapy, low dose chemotherapy, and radiation thus avoiding more intensive combination chemotherapy regimens for patients with these biomarkers. Clinical trial information: NCT03257163 .

Background: The role of immune checkpoint inhibitors (ICI) has not been elucidated in ER+/Her2- metastatic breast cancer (MBC). Previous studies have demonstrated a subset of these patients may derive benefit from immunotherapy in combination with endocrine therapy. We hypothesized that pembrolizumab in combination with fulvestrant would demonstrate disease control with acceptable toxicity profile. Methods: This was a multicenter, single arm, open label Phase II Simon’s two-stage optimal design study in patients with ER+/HER2- MBC. The study was conducted through the BIG TEN Cancer Research Consortium. Patients received no more than 2 prior lines of endocrine or chemotherapy in the metastatic setting. Treatment consisted of pembrolizumab 200 mg every 3 weeks in combination with fulvestrant. The primary endpoint was to evaluate the clinical benefit rate (CBR: SD+PR+CR). The anti-tumor activity of pembrolizumab plus fulvestrant was measured by RECIST 1.1, irRECIST, and progression free survival (PFS). Scheduled staging scans occurred every 3 cycles (9 weeks). Secondary endpoints included safety and tolerability. PD-L1 status and next generation sequencing (NGS) by Tempus was performed on available samples to investigate biomarkers of response and the underlying mutational landscape. (NCT03393845). Results: Forty-seven patients were enrolled, with median age of 61. Majority of patients (n=32, 70%) received 1 prior line of therapy in the metastatic setting (range 0-2). Forty patients (87%) had prior treatment with CDK4/6 inhibitors, with 1 patient who received it in the adjuvant setting on a clinical trial. Eleven patients (24%) received prior fulvestrant, and 1 received chemotherapy in the metastatic setting. Forty-six patients were treated with at least 1 cycle, 44 were efficacy-evaluable, and 43 remained on study at the time of first restaging imaging. One patient came off study due to clinical progression and was included in the final response analysis. Two patients without radiographic or clinical progression withdrew after adverse events unrelated to the study drugs and were not included in the final response analysis. The median PFS in evaluable patients was 3.2 months (range 0.2-23.3). The CBR at 18 weeks was 36.4% (n=16/44) by RECIST 1.1. Of the 43 patients who underwent first restaging scan, 22 (50%) patient achieved disease control, including 17 patients with stable disease and 5 patients with partial response. Amongst patients who achieved disease control, the median duration of response was 6 months (range 2.3-21.3 months). Twenty-two patients had either radiographically confirmed progression on first restaging scan or clinical progression. The most common treatment related adverse effects (TRAEs) were AST elevation (n= 15, 31.9%), ALT elevation (n= 12, 25.5%), and fatigue (n= 14, 29.8%). Majority of TRAEs (93.5%) were G1-2. TRAEs of interest included hypothyroidism (n= 8, 17.0%), hot flashes (n= 3, 6.4%), arthralgia (n= 4, 8.5%), and pneumonitis (n= 1, 2.1%, G2). There were 7 (15%) patients who experienced G3 toxicities (arthralgia, anemia, hypocalcemia, decreased lymphocyte, rash, weight loss) and of these one patient (2.1%) discontinued the study drug due to elevated AST/ALT. There were no G4+ TRAEs. In patients with available tissue for NGS utilizing the Tempus platform (648 gene panel for next generation sequencing, whole exome, and RNA sequencing), genomic alterations and tumor mutational burden were evaluated. Response will be correlated with PD-L1 status by combined positive score (CPS), prior fulvestrant exposure, BMI, and biomarkers identified on NGS as exploratory analyses. Conclusions: The combination of pembrolizumab and fulvestrant in ER+/HER2- MBC demonstrated a manageable toxicity profile with durable response in patients who achieved disease control. The combination may be considered for further exploration to better understand biomarkers of response to ICI in this population. Citation Format: Nancy Chan, Dirk Moore, Nadia Baka, Kari Wisinski, Jairam Krisnamurthy, Jatin Rana, Pavan Tandra, Douglas Marks, Malinda West, Deimante Tamkus, Yue Wang, Chunxia Chen, Jacqueline Wang, Lisa Arendt, Kim Hirshfield, Mridula George, Shridar Ganesan, Deborah Toppmeyer, Coral Omene. A phase II study of pembrolizumab plus fulvestrant in ER positive, HER2 negative advanced/metastatic breast cancer patients [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2024; 2024 Dec 10-13; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(12 Suppl):Abstract nr P2-07-21.

BackgroundPost-resection detection of cell-free DNA (cfDNA) is strongly prognostic of recurrence for patients with localized colorectal cancer (CRC). The sensitivity and specificity of this biomarker in the setting of CRC liver metastases (CRCLM) have not yet been systematically quantified.MethodsPubMed was queried from database inception to June 2, 2023 for English-language publications reporting post-operative cfDNA status and recurrence-free survival (RFS) in patients with resected CRCLM. Weighted mean cfDNA positivity rates and RFS probabilities were utilized to estimate the sensitivity and specificity for recurrence at 1, 3 and 5 years after surgery. Recurrence risk using hazard ratios (HRs) and 95% CIs were calculated using a random-effects model and the DerSimonian-Laird method.ResultsOf 98 records, 10 studies (all non-randomized) were eligible, inclusive of 669 patients. The median weighted follow-up from surgical resection was 30.6 months (range 9.7–77.0 months). The mean postoperative cfDNA positivity rate was 38.5%, and cfDNA status was prognostic of RFS in 10 of 10 (100%) studies with a pooled HR of 3.11 (95% CI 2.29–4.22). Among cfDNA-positive patients, the weighted rate of recurrence was 75.0%, 92.5%, and 96.8% at 1, 3 and 5 years, respectively. Among cfDNA-negative patients, the weighted rate of recurrence was 35.7%, 59.7% and 60.7% at 1, 3 and 5 years, respectively. Sensitivity and specificity of cfDNA positivity was 67.8% and 30.0% for recurrence within 1 year, 60.9% and 15.7% for recurrence within 3 years, and 61.5% and 7.6% for recurrence within 5 years, respectively.ConclusionscfDNA-positivity following resection of CRCLM is highly prognostic of recurrence, which may have implications for treatment escalation strategies for this molecularly selected cohort. In contrast, recurrence was common in the cfDNA-negative cohort, cautioning against de-escalation strategies for these patients.

BACKGROUND:Plinabulin is a GEF-H1 releasing agent with an immune-enhancing function. We report results from a multicenter Phase I/II study (NCT03575793) assessing plinabulin in combination with nivolumab and ipilimumab for the treatment of recurrent SCLC. METHODS:In Phase I, patients were enrolled using a 3 + 3 design to determine dose-limiting toxicities (DLTs) and recommended Phase 2 dose (RP2D). Patients received nivolumab (1 mg/kg), ipilimumab (3 mg/kg), and plinabulin (in escalating doses) on day 1 of each 21-day cycle for 4 cycles followed by maintenance with plinabulin and nivolumab. In phase II, patients with recurrent PD(L)1 inhibitor resistant SCLC were enrolled. The primary objective was median progression-free survival (PFS). RESULTS:Between 9/2018 and 2/2023, 39 patients were enrolled, and 36 patients received study treatment and were evaluable for safety (16 in Phase I; 20 in Phase II). In the phase I dose-escalation, there were 2 DLTs; grade 3 altered mental status lasting <24 h and grade 3 infusion reaction. The Plinabulin RP2D was determined to be 30 mg/m2. Common TRAEs were vomiting (44 %), nausea (42 %), and infusion reaction (36 %); 6 % of patients had a ≥grade 3 TRAE. Five patients (14 %) had ≥grade 3 irAEs; there were no cases of immune-related pneumonitis. In the efficacy analysis in 27 patients, the median PFS was 1.6 months (95 % CI 1.2 to 2.7) and the trial did not meet the pre-specified target median PFS of 3.5 months. Four patients treated at 30 mg/m2 had PR (confirmed 1, unconfirmed 3); 5 patients had SD with a CBR of 33 %. Two of 8 patients treated in phase I at the lower 20 mg/m2 dose had confirmed PR, with 1 patient on the drug regimen for >90 cycles. The median OS and follow-up time were 5.5 months and 2.5 months respectively. CONCLUSIONS:Plinabulin in combination with nivolumab and ipilimumab was tolerable at the dose of 30 mg/m2. While the clinical responses in PD-1 resistant SCLC were limited, some patients had a long duration of response. The number of ≥grade 3 irAE with the combination were lower than expected.

Background: Racial and ethnic disparities have been observed in the multidisciplinary management of pancreatic ductal adenocarcinoma. Intraductal papillary mucinous neoplasm is the most common identifiable precursor to pancreatic ductal adenocarcinoma, where early surgical intervention before the development of an invasive intraductal papillary mucinous neoplasm improves survival. The association of race/ethnicity with the risk of identifying invasive intraductal papillary mucinous neoplasms during resection has not been previously defined. Methods: The American College of Surgeons National Quality Improvement Program targeted pancreatectomy database (2014-2021) was queried for patients with race/ethnicity data who underwent resection of an intraductal papillary mucinous neoplasm. Backward Wald logistic regression modeling (P < 0.05 for entry; P > .10 for removal) was used to identify independent predictors of invasion. Results: A total of 4,505 cases of resected intraductal papillary mucinous neoplasms were identified, with 923 (20.5%) demonstrating invasive intraductal papillary mucinous neoplasms. The cohort of individuals other than non-Hispanic Whites were significantly more likely to have invasive intraductal papillary mucinous neoplasms (White, 19.9%; Black, 24.2%; Asian, 23.7%; Hispanic, 22.6%; P = .026). Such disparity could not be explained by greater comorbidity, as non-White patients were significantly younger (age <65 years: 41.7% vs 33.2%, P < .001) and had better physical status (American Society of Anesthesiologists score <= 2: 28.8% vs 25.2%, P = .053). After controlling for clinicodemographic variables, being an individual of race/ethnicity other than White was independently associated with higher odds of invasive intraductal papillary mucinous neoplasms (odds ratio, 1.280; 95% confidence interval, 1.046-1.566; P = .017). No differences in postoperative morbidity were observed. Conclusion: In a national cohort of patients with resected intraductal papillary mucinous neoplasms, individuals who identified as being of race/ethnicity other than White were significantly more likely to have invasive intraductal papillary mucinous neoplasms during surgical resection. (c) 2024 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

BACKGROUND:Patients undergoing hematopoietic stem cell transplant (HSCT) experience barriers to quality sleep. Frequent vital sign checks are necessary early posttransplant given risk of complications but can disrupt sleep. This study tested feasibility and acceptability of extending time between checking vitals (EVs) from every 4 to every 6 h to improve sleep.PROCEDURE:HSCT patients ages 8-21 years (N = 50, mean age = 14.06, SD = 3.58) and their caregivers were enrolled 1-2 days prior to transplant, and 40 patients completed the 15-day study (NCT04106089). Patients wore an actigraph to estimate sleep and provided self- and caregiver-report of sleep. Sleep was observed for nights 0 to +4 posttransplant, and patients were then randomized to EVs either Days +5 to +9 or +10 to +14. Patients were assessed daily for medical eligibility to receive EVs; on days patients were eligible, nightshift nurses (N = 79) reported EV acceptability.RESULTS:Of 200 potential nights for EVs (5 nights x 40 patients), patients were eligible for EVs on 126 nights (63% of eligible nights), and patients received EVs on 116 (92%) of eligible nights. Most patients received EVs ≥3 nights (n = 26, 65%, median = 3 nights). Most patients (85%), caregivers (80%), and nurses (84%) reported that patients used the additional 2 h during EVs for sleep, with reporters indicating moderate to high acceptability. There was preliminary evidence of efficacy indicated by caregiver-reported sleep disturbance and actigraphy-estimated improvements in sleep efficiency during EVs.CONCLUSION:Extending time between vitals checks is highly acceptable to patients, caregivers, and nurses, and may offer a feasible approach to improve sleep in pediatric HSCT.

ABSTRACT Background Post-resection detection of cell-free DNA (cfDNA) is strongly prognostic of recurrence for patients with localized colorectal cancer (CRC). The sensitivity and specificity of this biomarker in the setting of CRC liver metastases (CRCLM) have not yet been systematically quantified. Methods PubMed was queried from database inception to June 2, 2023 for English-language publications reporting post-operative cfDNA status and recurrence-free survival (RFS) in patients with resected CRCLM. Weighted mean cfDNA positivity rates and RFS probabilities were utilized to estimate the sensitivity and specificity for recurrence at 1, 3 and 5 years after surgery. Recurrence risk using hazard ratios (HRs) and 95% CIs were calculated using a random-effects model and the DerSimonian-Laird method. Results Of 98 records, 10 studies (all non-randomized) were eligible, inclusive of 669 patients. The median weighted follow-up from surgical resection was 30.6 months (range 9.7-77.0 months). The mean postoperative cfDNA positivity rate was 38.5%, and cfDNA status was prognostic of RFS in 10 of 10 (100%) studies with a pooled HR of 3.11 (95% CI 2.29-4.22). Among cfDNA-positive patients, the weighted rate of recurrence was 75.0%, 92.5%, and 96.8% at 1, 3 and 5 years, respectively. Among cfDNA-negative patients, the weighted rate of recurrence was 35.7%, 59.7% and 60.7% at 1, 3 and 5 years, respectively. Sensitivity and specificity of cfDNA positivity was 67.8% and 30.0% for recurrence within 1 year, 60.9% and 15.7% for recurrence within 3 years, and 61.5% and 7.6% for recurrence within 5 years, respectively. Conclusions cfDNA-positivity following resection of CRCLM is highly prognostic of recurrence, which may have implications for treatment escalation strategies for this molecularly selected cohort. In contrast, recurrence was common in the cfDNA-negative cohort, cautioning against de-escalation strategies for these patients.

BACKGROUND:Differentiated thyroid cancer (DTC) affects thousands of lives worldwide each year. Typically, DTC is a treatable disease with a good prognosis. Yet, some patients are subjected to partial or total thyroidectomy and radioiodine therapy to prevent local disease recurrence and metastasis. Unfortunately, thyroidectomy and/or radioiodine therapy often worsen(s) quality of life and might be unnecessary in indolent DTC cases. On the other hand, the lack of biomarkers indicating a potential metastatic thyroid cancer imposes an additional challenge to managing and treating patients with this disease.AIM:The presented clinical setting highlights the unmet need for a precise molecular diagnosis of DTC and potential metastatic disease, which should dictate appropriate therapy.MATERIALS AND METHODS:In this article, we present a differential multi-omics model approach, including metabolomics, genomics, and bioinformatic models, to distinguish normal glands from thyroid tumours. Additionally, we are proposing biomarkers that could indicate potential metastatic diseases in papillary thyroid cancer (PTC), a sub-class of DTC.RESULTS:Normal and tumour thyroid tissue from DTC patients had a distinct yet well-defined metabolic profile with high levels of anabolic metabolites and/or other metabolites associated with the energy maintenance of tumour cells. The consistency of the DTC metabolic profile allowed us to build a bioinformatic classification model capable of clearly distinguishing normal from tumor thyroid tissues, which might help diagnose thyroid cancer. Moreover, based on PTC patient samples, our data suggest that elevated nuclear and mitochondrial DNA mutational burden, intra-tumour heterogeneity, shortened telomere length, and altered metabolic profile reflect the potential for metastatic disease.DISCUSSION:Altogether, this work indicates that a differential and integrated multi-omics approach might improve DTC management, perhaps preventing unnecessary thyroid gland removal and/or radioiodine therapy.CONCLUSIONS:Well-designed, prospective translational clinical trials will ultimately show the value of this integrated multi-omics approach and early diagnosis of DTC and potential metastatic PTC.

This is a retrospective study examining the use of intraoperative ultrasound (IOUS) in breast conserving surgery and the impact of IOUS on margin positivity and re-excision rates and factors contributing to breast surgeon utilization of IOUS. Conducted in patients with preoperative diagnosis of breast cancer undergoing breast-conserving surgery by breast surgeons at multiple centers within a single healthcare system. There was no significant difference in re-excision rates between IOUS and WGL or among the 4 surgeons. Ultrasound-certified surgeons were more likely to utilize IOUS, and re-excision rates trended higher for WGL. Objectives: The purpose of this study is to evaluate the utilization of intraoperative ultrasound (IOUS) for tumor local-ization in breast-conserving surgery and to examine its impact on margin positivity and re-excision rates. Additionally, the study seeks to identify factors contributing to surgeon utilization of IOUS. Methods: A retrospective chart review was conducted of patients with preoperative diagnosis of breast cancer undergoing breast-conser ving surger y by breast surgeons at multiple centers within a single healthcare system. Characteristics such as lesion size, palpability, histol-ogy, receptor status, and use of neoadjuvant chemotherapy were recorded. Re-excision rates were determined based on localization technique and surgeons' status of breast ultrasound certification. Results: A total of 671 cases were performed, with 322 meeting study inclusion. 57 cases utilized IOUS, 250 utilized preoperative wire-guided localization (WGL), 10 used both methods and 5 cases used neither method. There was no significant difference in re-excision rates between IOUS and WGL or among the four surgeons. Ultrasound-certified surgeons were more likely to utilize IOUS, and re-excision rates trended higher for WGL, which may be clinically significant. Conclusion: Increasing familiarity with and utilization of IOUS during breast-conserving surgery may be clinically advantageous over traditional localization techniques. Ultrasound certification may lead to increased use of IOUS among surgeons.

PURPOSE:Shorter courses of breast radiotherapy are offered as an alternative to 4 weeks of whole-breast irradiation after lumpectomy, including brachytherapy. A prospective phase 2multi-institution clinical trial to study 3-fraction accelerated partial breast irradiation delivered by brachytherapy was conducted. METHODS AND MATERIALS:The trial treated selected breast cancers after breast-conserving surgery with brachytherapy applicators that delivered 22.5 Gy in 3 fractions of 7.5 Gy. The planning treatment volume was 1 to 2 cm beyond the surgical cavity. Eligible women were age ≥45 years with unicentric invasive or in situ tumors ≤3 cm excised with negative margins and with positive estrogen or progesterone receptors and no metastases to axillary nodes. Strict dosimetric parameters were required to be met and follow up information was collected from the participating sites. RESULTS:Two hundred patients were prospectively enrolled; however, a total of 185 patients who were enrolled were followed for a median of 3.63 years. Three-fraction brachytherapy was associated with low chronic toxicity. There was excellent or good cosmesis in 94% of patients. There were no grade 4 toxicities. Grade 3 fibrosis at the treatment site was present in 1.7% and 32% percent had grades 1 or 2 fibrosis at the treatment site. There was 1 rib fracture. Other late toxicities included 7.4% grade 1 hyperpigmentation, 2% grade 1 telangiectasias, 1.7% symptomatic seromas, 1.7% abscessed cavities, and 1.1% symptomatic fat necrosis. There were 2 (1.1%) ipsilateral local recurrences, 2 (1.1%) nodal recurrences and no distant recurrences. Other incidents included one contralateral breast cancer and 2 second malignancies (lung). CONCLUSIONS:Ultra-short breast brachytherapy is feasible and has excellent toxicity and could be an alternative to standard 5-day, 10 fraction accelerated partial breast irradiation in eligible patients. Patients from this prospective trial will continue to be followed to evaluate long-term outcomes.

103 Background: Novel strategies to improve the efficacy of immune checkpoint inhibitors in microsatellite stable (MSS) mCRC are needed. CV301 is a vector-based vaccine that expresses carcinoembryonic antigen (CEA) and mucin 1 (MUC1), and in a phase II study in resected hepatic limited mCRC significantly improved OS compared with unvaccinated contemporary controls. Methods: In this multi-center randomized phase II study, patients with previously untreated resectable hepatic-limited mCRC were randomized to perioperative nivolumab + mFOLFOX +/- CV301 (Arm B) with a primary endpoint of 3-year OS. Treatment included mFOLFOX-nivo (+/- CV) x 4 cycles followed by resection, then 8 more cycles of mFOLFOX-nivo followed by maintenance nivo monthly for two years in both arms, and CV boosters concurrently with mFOLFOX, and then every 3 months for two years in arm B. Secondary endpoints of ORR (following induction pre-resection), PRR, and safety were determined. Correlative analyses included immune cell quantification using Immunoscore and T-cell clonality. Results: 17 patients were enrolled prior to premature closure for slow accrual (8 arm A, 9 arm B). At the time of data cutoff, 5 patients remained on treatment and no deaths had occurred. One patient was removed from study due to protocol non-compliance. The median age was 61, majority were male (59% vs 41%), and ECOG PS 0-1 (71% 0, 17% 1). All patients had complete surgical resection. Four patients (24%) experienced a SAE related to drug. The TRAE rate was 40.3%,. No AEs delayed/prevented surgical resection. The ORR in arm A was 50% (including 4 CR) and 87.5% in arm B (including 7 CR) (p=0.129, NS). There was no significant difference in pathologic response (p=0.9047). Correlative analyses demonstrated the Immunoscore CD3/CD8 predicted response to mFOLFOX + nivolumab, but did not correlate with response to CV301, though CV301 may induce a shift to predominantly cytotoxic CD8+ T cells. While there was no significant difference in T cell repertoire, clonality, fraction (TCFr) or richness, patients in arm B had significant decreases in blood TCFr and increase in tumor TCFr with treatment; those with CR had higher TCFr and clonality. Conclusions: The addition of CV301 to perioperative nivolumab and mFOLFOX was safe, did not delay or prevent surgical resection, and gave a higher response (p=ns due to sample size). Changes in T cells suggest a vaccine response. Clinical trial information: NCT03547999 . [Table: see text]

Supplementary Figures S1-S2; Supplementary Materials and Methods; Supplementary Table S1.

Supplementary figures and tables Supplementary Fig. S1. Quantitative RT-PCR (qPCR) validation of the expression of MT1A, MT2A, and ZnT1 in TOV112D cells after ZMC1 treatment. Supplementary Fig. S2. Quantitative RT-PCR (qPCR) validation of the knockout of MT1A and MT2A in the CRISPR-cas9 treated TOV112D cells. The ZnT1 expression was measured by qPCR and showed a six-fold increase in the KO cells. Supplementary Fig. S3. FluoZin-3 fluorescent imaging in the TOV112D cells with knockdown of either MT1A or MT2A by siRNA transfection followed by treatment of 1 ï­M ZMC1 for 0 - 8 hours. The scale bar = 50 ï­m. The transfection efficiency was measured by qPCR and shown on the right. Supplementary Fig. S4. Sensitivity of TOV112D cells with siRNA knockdown of MT2A and MT1X was measured by cell viability assay (Calcein-AM assay). The cells were transfected by siRNA followed by treatment of serial dilutions of ZMC1 for 72 hours. The EC50s were shown on the right. Supplementary Fig. S5. The TOV112D cells with various time of exposure of the serial dilutions of ZMC1 and then the drug-free medium was replaced for the incubation up to 72 hours. Cell viability measurement was performed using Guava ViaCount. Supplementary Fig. S6. In vivo Maximum tolerated dose (MTD) studies and efficacy in subcutaneous tumors from KPC mouse tumor cell line. (A) MTD studies were perfomed by treating the mice with various doses of ZMC1 by IP for 7 days. The survival is shown in Kaplan-Meier curve. (B) In MTD studies, the health, behavior and the body weight was monitored every day. The body weight change is shown. Supplementary Fig. S7. Pharmacodynamic analysis of the ZMC1 in tumors from KPC-172 and KPC-270. The tumors were harvested one hour after mice received the last dose of ZMC1 (5 mg/kg once daily for three days). Immunohistochemistry staining of the tumor tissues was performed using Cleaved caspase-3 (CC3). (A) Representative IHC staining is shown. (B) The quantitation is shown. Supplementary Fig. S8. Sensitivity of TOV112D cells to Zn-1 was evaluated by cell viability assay (MTS assay). The cells were treated with serial dilutions of ZMC1 or Zn-1 for 72 hours. Supplementary Fig. S9. LC-MS/MS analysis of ZMC1 and Zn-1. (A) ZMC1 monomer. (B) Zn-1 (the complex). A peak in MS (right panel) at 532, indicating the intact complex. Supplementary Fig. S10. In vivo Maximum tolerated dose (MTD) studies for Zn-1. (A) MTD studies were perfomed by treating the mice with various doses of Zn-1 by IP for 9 days. The survival is shown in Kaplan-Meier curve. (B) In MTD studies, the health, behavior and the body weight was monitored every day. The body weight change is shown. Supplementary Fig. S11. The gene expression of p53 target genes Puma, Noxa and p21 was increased in p53R172H but not in p53R270H tumor tissues. The mice bearing subcutaneous tumors from cell lines KPC-p53R172H vs. KPC-p53R270H were treated with one dose of ZMC1 by IV for 24 hours. The gene expression was measured by qRT-PCR to the RNA extracted from the tumor tissues. The statistical analysis was performed as unpaired, two-tailed t test with confidence intervals of 95%. **, p value < 0.0001. Supplemental Table S1. The 16 most regulated genes of 37 zinc regulatory genes in TOV112D cells after ZMC1 treatment by RNAseq analysis Supplemental Table S2. Efflux ratio of ZMC1 was measured using the Caco-2 permeability assay.

e16111 Background: Despite advances in therapy, outcomes of patients with gastric cancer in the US remain poor. Recent data demonstrated that certain subtypes of gastric cancer are less responsive to perioperative chemotherapy. Preliminary data suggest that patients with microsatellite unstable tumors (MSI-H), EBV expressing tumors, and tumors with high PD-L1 expression may benefit from immunotherapy. We initiated a clinical trial to evaluate the benefit of PD-1 checkpoint immunotherapy in this subset of patients with resectable gastric cancer. Methods: Interim analysis performed on this phase 2 multi-institutional clinical trial (NCT03257163) is presented. Patients with clinically staged T2-T4, N0-N3, M0 gastric adenocarcinoma are evaluated for loss of mismatch repair proteins, expression of EBV or PDL1 expression with CPS > 1%. Consented patients receive 2 cycles of neoadjuvant pembolizumab followed by surgical resection. Following surgery, patients receive adjuvant chemoradiation (45 Gy) with 5 cycles of capecitabine and concurrent pembrolizumab, followed by up to 1 year of pembrolizumab. The primary endpoint is disease-free survival. Results: Of the 15 patients currently enrolled (planned enrollment = 40), 6 patients were MSI-H, 2 EBV (+), and 7 had PDL1 expression with CPS > 1%. Two patients did not undergo surgical resection as 1 patient was found to have peritoneal disease at time of exploration and second was deemed too frail to proceed with surgery. In the 13 patients who underwent surgical resection, all are alive without evidence of recurrent disease (follow up 1 month – 22 months). After 2 cycles of pembrolizumab, 2 patients with MSI-H tumors had pathologic complete response. Clinical T stage was downstaged in 5 patients and clinical N stage was downstaged in 2 patients. PD-1 checkpoint immunotherapy was well tolerated with minimal need for dose reduction and limited toxicity. Conclusions: Early results from our phase 2 clinical trial show immunotherapy to be well tolerated with limited toxicity. Following 2 cycles of pembrolizumab, 2 patients with MSI-H had complete pathologic response and above a third of our patients were downstaged. No recurrences have been observed in the short-term follow-up of surgically resected patients. Clinical trial information: NCT03257163.

Background Plinabulin (BPI-2358) is a GEF-H1 releasing agent that has immune-enhancing function by inducing dendritic cell maturation and decreasing regulatory T cells.1–3 Preclinical studies support the hypothesis that plinabulin potentiates the antitumor activity of dual checkpoint inhibition (CPI) with nivolumab and ipilimumab.2 Plinabulin may also reduce immune-related adverse events (AEs) from CPI through its phosphodiesterase-4 (PDE4) inhibitory activity which is associated with anti-inflammatory effects. We report results from a Phase II study assessing plinabulin in combination with nivolumab and ipilimumab. Methods In this multi-center phase II study (NCT03575793), patients with recurrent extensive-stage SCLC who had progressed on prior platinum-based chemotherapy and anti-PD(L)1 therapy were enrolled. Patients received nivolumab (1 mg/kg), ipilimumab (3 mg/kg) and plinabulin (as per dose escalation schema) IV on day 1 of each 21-day cycles. After completion of 4 cycles, patients continued therapy with nivolumab (240 mg) and plinabulin (30 mg/m2) every 2 weeks till progression or intolerable toxicity. The primary objective was median progression-free survival (PFS). Correlative analysis includes inflammatory biomarkers: hsCRP, ESR, SAA and haptoglobin. Results Between 1/2020 and 2/2023, 31 patients with PD(L)-1 resistant, pre-treated SCLC were enrolled and 28 patients received at least one cycle of study treatment. Median age was 64 years (range 43 to 80); 12 patients were female. Median PFS was 1.6 months (95% CI 1.2 to 2.7). Three patients had PR (confirmed 1, unconfirmed 2) and all three had tumor reduction >50%. Median time to response was 6 weeks. An additional 6 patients had SD as the best overall response. The most common treatment-related AEs (all grades) were nausea (10; 46%), vomiting (10; 46%), infusion reaction (9; 32%), hypertension (7; 25%) and fatigue (6, 17%). Fourteen patients (50%) had at least one grade 3 or worse treatment-related AE with hypertension (5; 18%) being the most common. Four patients (14%) had grade 3 or worse irAE requiring steroids (1 diarrhea, 1 hepatotoxicity, 2 elevated lipase). There were no cases of immune-related pneumonitis reported. Conclusions Plinabulin in combination with nivolumab and ipilimumab had limited clinical benefit for the treatment of pre-treated, PD(L)-1 resistant SCLC and the trial did not meet the pre-specified target median PFS of 3.5 months. The number of patients experiencing grade 3 or worse irAE was lower than expected with the addition of plinabulin to dual checkpoint inhibitors and warrants further study to explore if plinabulin plays a role in reducing irAEs. Acknowledgements Funding support was provided by BeyondSpring Pharma and Bristol Myers Squibb. Trial Registration The trial is registered at clinicaltrials.gov as NCT03575793. References Natoli M, et al. Plinabulin, a Distinct Microtubule-Targeting Chemotherapy, Promotes M1-Like Macrophage Polarization and Anti-tumor Immunity. Front Oncol. 2021 Mar 3;11:644608. Malhotra J, et al. A phase I trial of plinabulin in combination with nivolumab and ipilimumab in patients with relapsed small cell lung cancer (SCLC): Big Ten Cancer Research Consortium (BTCRC-LUN17–127) study. ASCO Annual Meeting June 4 2021. Kashyap AS, et al. GEF-H1 Signaling upon Microtubule Destabilization Is Required for Dendritic Cell Activation and Specific Anti-tumor Responses. Cell Rep. 2019 Sep 24;28(13):3367−3380.e8. Ethics Approval The study was approved by the IRB of each of the participating institutions. All participants gave informed consent before taking part in the trial.

INTRODUCTION:Frequency of PD-L1 expression and the role of immunotherapy in malignant peritoneal mesothelioma (MPM) have not been well characterized. The purpose of this study was to determine PD-L1 expression in patients with MPM and perform an exploratory analysis for associations between PD-L1 and its biological behavior in MPM. METHODS:Tumor samples were collected from patients undergoing surgical interventions between January 2018 and June 2020. Specimens were stained with anti-PD-L1 antibodies (Dako 22c3) and positivity was determined by tumor proportion score (TPS) or combined positive score (CPS) being ≥1%. RESULTS:Twenty one samples were obtained from 21 patients. Sixteen of 21 (76%) samples were CPS positive and 9 of 21 (43%) were TPS positive. Three samples had more aggressive biphasic/sarcomatoid histology and a high CPS and TPS (CPS: 3, 75, 95%; TPS: 2, 60, 90%). On an exploratory analysis, as the CPS or TPS threshold increased, there was a trend towards worse survival. CONCLUSIONS:MPM has a high frequency of PD-L1 expression, which may be associated with more aggressive tumor biology. These data provide the foundation for continued evaluation of checkpoint inhibition in patients with MPM.

Knowledge of cellular location is key to understanding the biological function of proteins. One commonly used large-scale method to assign cellular locations is subcellular fractionation, followed by quantitative mass spectrometry to identify proteins and estimate their relative distribution among centrifugation fractions. In most of such subcellular proteomics studies, each protein is assigned to a single cellular location by comparing its distribution to those of a set of single-compartment reference proteins. However, in many cases, proteins reside in multiple compartments. To accurately determine the localization of such proteins, we previously introduced constrained proportional assignment (CPA), a method that assigns each protein a fractional residence over all reference compartments (Jadot Mol. Cell Proteomics 2017, 16(2), 194-212. 10.1074/mcp.M116.064527). In this Article, we describe the principles underlying CPA, as well as data transformations to improve accuracy of assignment of proteins and protein isoforms, and a suite of R-based programs to implement CPA and related procedures for analysis of subcellular proteomics data. We include a demonstration data set that used isobaric-labeling mass spectrometry to analyze rat liver fractions. In addition, we describe how these programs can be readily modified by users to accommodate a wide variety of experimental designs and methods for protein quantitation.