This case-control study evaluates whether adjuvant radiotherapy is associated with overall survival among patients with surgically resected stage III Merkel cell carcinoma.

Fragmentation of care (FC, the receipt of care at > 1 institution) has been shown to negatively impact cancer outcomes. Given the multimodal nature of breast cancer treatment, we sought to identify factors associated with FC and its effects on survival of breast cancer patients. A retrospective analysis was performed of surgically treated, stage I–III breast cancer patients in the 2004–2020 National Cancer Database, excluding neoadjuvant therapy recipients. Patients were stratified into two groups: FC or non-FC care. Treatment delay was defined as definitive surgery > 60 days after diagnosis. Multivariable logistic regression was performed to identify factors predictive of FC, and survival was compared using Kaplan–Meier and multivariable Cox proportional hazards methods. Of the 531,644 patients identified, 340,297 (64.0

BACKGROUND:In response to the COVID-19 pandemic, the Pandemic Breast Cancer Consortium (PBCC) published recommendations for triage of breast cancer patients. The recommendations included neoadjuvant treatment of early-stage breast cancer patients experiencing delays in surgery. This study evaluated national patterns of neoadjuvant treatment according to triage guidelines. METHODS:Patients treated with surgery (upfront or post-neoadjuvant) in 2018-2020 were collected from the National Cancer Database. The proportions of patients treated according to the PBCC triage guidelines were calculated in 2020 and compared with similar cohorts in 2018-2019. Patient and hospital factors were evaluated for association with treatment. RESULTS:Among cT1N0 ER+/PR+/HER2- patients, those treated in 2020 were more likely to receive neoadjuvant endocrine therapy (NET) compared with those before that time (odds ratio [OR], 3.08; range, 2.93-3.24). Among the patients with cT2N0 or cT1N1 disease, NET was more common in 2020 (OR, 1.76; range, 1.65-1.88). Academic facility, black or Asian race, more comorbidities, and the New England/Middle Atlantic region were associated with NET use. CONCLUSIONS:During the COVID-19 pandemic, expanded utilization of neoadjuvant therapy for surgical breast cancer patients was observed. Health care system limitations during the pandemic contributed to expanded adoption of neoadjuvant therapy for early breast cancer, contrary to usual practice. Long-term outcomes for patients treated according to PBCC recommendations should be closely monitored.

Background Since 2016, the Choosing Wisely campaign has recommended against routine axillary surgery in elderly patients with early stage, hormone receptor positive (ER+) breast cancer. The objective was to evaluate factors associated with axillary surgery in breast cancer patients meeting criteria for sentinel lymph node biopsy (SLNB) omission and identify potential disparities. Methods Female patients age ≥70 years with cT1-2N0M0, ER+, HER2-negative breast cancer diagnosed after publication of the Choosing Wisely recommendations, between 2016 and 2019, were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Patient demographics and tumor characteristics associated with axillary surgery were analyzed. Results Of the 31 756 patients meeting omission criteria, 25 771 (81.2%) underwent axillary surgery. Hispanic ethnicity, median household income between $35,000 and $70,000, treatment in rural areas, poor differentiation, lobular and mixed lobular with ductal histology, T2 tumors, radiation therapy, and systemic therapy were factors associated with receiving axillary surgery on multivariable analysis. In the axillary surgery cohort, a median of 2 (IQR = 2) nodes were examined and 529 (2.1%) patients were found to have 1 or more positive lymph nodes. Discussion Among elderly patients meeting Choosing Wisely criteria for SLNB omission, particular racial, ethnic, socioeconomic, and geographic populations may be at increased risk for potential over treatment. Identification of these factors provides specific opportunities for education and implementation of de-escalation of unnecessary procedures.

e18842 Background: The National Cancer Database (NCDB) introduced COVID-specific variables in 2020 to assess the impact of the pandemic on cancer care. Variables include (1) any SARS-CoV-2 test and (2) SARS-CoV-2 test result. We evaluated patterns of breast cancer reporting and mortality compared to pre-pandemic. Methods: From the 2020 NCDB breast cancer participant user file, we separately examined reporting and mortality in the years 2017-2020. Pre-pandemic years (2017-2019) were used as a baseline to evaluate secular trends not related to the pandemic. For patients diagnosed in the study period, patient/hospital factors associated with complete reporting (CR) or no reporting (NR) of COVID variables were compared. For patients who died during the study period, yearly mortality rate and overall survival (OS) were examined overall and by stage. Patient/hospital factors were examined for associations with year of death. Results: Fewer breast cancer cases were reported in 2020 (232,023) compared to 2019 (268,210) and 2018 (260,259). In 2020, there were 97,810 (42%) with NR and 116,455 (50%) with CR of COVID variables. On multivariable analysis, patients with NR were more likely to be > 70 years old, of Asian race, with Medicare coverage, lower education quartile, and treated at community hospitals and those in the Middle Atlantic region. There were 60,933 deaths in 2020, 64,502 in 2019, 63,865 in 2018, and 61,930 in 2017. There were significantly fewer stage 4 deaths in 2020 compared to prior (Table). Although there was a steady trend of increasing OS across the 4-year period, the incremental increase from 2019 to 2020 was higher than expected based on previous years. This finding was particularly true for stage 4 patients (median OS: 31.4 months in 2020, 20.2 months in 2019). On multivariable analysis, 2020 mortalities were less likely in patients > 80 years old (OR 0.88, p < .01) or with stage 3 (0.81, p < .01) or stage 4 (0.64, p < .01) disease, and more likely at academic centers (1.05, p < .01) than in 2017-2019. Conclusions: Non-reporting of COVID data is not at random, and is more common in populations at risk. In addition, fewer breast cancer mortalities were reported in 2020, with higher than expected OS. These findings suggest that OS was artificially increased in 2020 due to underreporting of patients who may be at higher risk of mortality. Accurate and complete data is crucial for evaluating the pandemic's impact on patient care. Underreporting of patients who may be most vulnerable limits our ability to comment on the true impact of the pandemic. These limitations must be considered to avoid blind spots in evaluation of pandemic data and risk deepening disparities. [Table: see text]

Background: Epidermal growth factor receptor (EGFR) is overexpressed in pancreatic cancer. EGFR expression plays a potentially important role in modulation of tumor sensitivity to either chemotherapy or radiotherapy. Erlotinib is a receptor tyrosine kinase inhibitor with specificity for EGFR/HER1. A phase II trial was conducted to explore the efficacy of a regimen utilizing erlotinib and proton therapy. Methods: Patients with unresectable or borderline resectable non-metastatic adenocarcinoma of the pancreas were included. Patients received 8-week systemic treatment with gemcitabine 1,000 mg/m(2) and erlotinib 100 mg (GE). If there was no evidence of metastatic disease after GE, then patients preceded with proton therapy to 50.4 Gy in 28 fractions with concurrent capecitabine 825 mg/m(2) (CPT). This was followed with oxaliplatin 130 mg/m(2) and capecitabine 1,000 mg/m2 (CapOx) for 4 cycles. The primary study objective was 1-year overall survival (OS). The benchmark was 43% 1-year survival as demonstrated in RTOG/NRG 98-12. The Kaplan-Meier method was used to estimate the one-year OS and the median OS and progression-free survival (PFS). Results: The study enrolled 9 patients ages 47-81 years old (median 62) between January 2013 and March 2016, when the trial was dosed due to low patient accrual. The 1-year OS rate was 55.6% (95% CI: 31% to 99%). The median OS was 14.1 months (95% CI: 11.4-NE) and the median PFS was 10.8 months (95% CI: 7.44-NE). A majority of patients completed CPT and GE, but only 33.3% completed the four cycles of CapOx. A third of patients experienced grade 3 toxicities, which were all hepatic along with one patient who also had grade 3 diarrhea. There were no grade 4 or 5 toxicities. Four patients were enrolled with borderline resectable disease, three of which were eligible for pancreaticoduodenectomy after GE and CPT treatment. One of two patients who underwent resection had a negative margin. Conclusions: This regimen for locally advanced pancreatic cancer (LAPC) exceeded the pre-specified benchmark and was safe and well tolerated. Additional investigations utilizing more current systemic treatment regimens with proton therapy are warranted.

Background We sought to determine factors affecting time to surgery (TTS) to identify potential modifiable factors to improve timeliness of care. Methods Patients with clinical stage 0-3 breast cancer undergoing partial mastectomy in 2 clinical trials, conducted in ten centers across the US, were analyzed. No preoperative workup was mandated by the study; those receiving neoadjuvant therapy were excluded. Results The median TTS among the 583 patients in this cohort was 34 days (range: 1-289). Patient age, race, tumor palpability, and genomic subtype did not influence timeliness of care defined as TTS ≤30 days. Hispanic patients less likely to have a TTS ≤30 days (P = .001). There was significant variation in TTS by surgeon (P < .001); those practicing in an academic center more likely to have TTS ≤30 days than those in a community setting (55.1% vs 19.3%, P < .001). Patients who had a preoperative ultrasound had a similar TTS to those who did not (TTS ≤30 days 41.9% vs 51.9%, respectively, P = .109), but those who had a preoperative MRI had a significantly increased TTS (TTS ≤30 days 25.0% vs 50.9%, P < .001). On multivariate analysis, patient ethnicity was no longer significantly associated with TTS ≤30 (P = .150). Rather, use of MRI (OR: .438; 95% CI: .287-.668, P < .001) and community practice type (OR: .324; 95% CI: .194-.541, P < .001) remained independent predictors of lower likelihood of TTS ≤30 days. Conclusions Preoperative MRI significantly increases time to surgery; surgeons should consider this in deciding on its use.

Introduction: Factors contributing to the use of preoperative MRI remain poorly understood. Methods: Data from a randomized controlled trial of stage 0-3 breast cancer patients undergoing breast conserving surgery between 2016 and 2018 were analyzed. Results: Of the 396 patients in this trial, 32.6% had a preoperative MRI. Patient age, race, ethnicity, tumor histology, and use of neoadjuvant therapy were significant predictors of MRI use. On multivariate analysis, younger patients with invasive lobular tumors were more likely to have a preoperative MRI. Rates also varied significantly by individual surgeon (p < 0.001); in particular, female surgeons (39.9% vs. 24.0% for male surgeons, p = 0.001) and those in community practice (58.9% vs. 14.2% for academic, p < 0.001) were more likely to order preoperative MRI. Rates declined over the two years of the study, particularly among female surgeons. Conclusions: Preoperative MRI varies with patient age and tumor histology; however, there remains variability by individual surgeon.

INTRODUCTION:De-escalation of breast cancer treatment aims to reduce patient and financial toxicity without compromising outcomes. Level I evidence and National Comprehensive Cancer Network guidelines support omission of adjuvant radiation in patients aged >70 y with hormone-sensitive, pT1N0M0 invasive breast cancer treated with endocrine therapy. We evaluated radiation use in patients eligible for guideline concordant omission of radiation. METHODS:Subgroup analysis of patients eligible for radiation omission from two pooled randomized controlled trials, which included stage 0-III breast cancer patients undergoing breast conserving surgery, was performed to evaluate factors associated with radiation use. RESULTS:Of 631 patients, 47 (7.4%) met radiation omission criteria and were treated by 14 surgeons at eight institutions. The mean age was 75.3 (standard deviation + 4.4) y. Majority of patients identified as White (n = 46; 97.9%) and non-Hispanic (n = 44; 93.6%). The mean tumor size was 1.0 cm; 37 patients (88.1%) had ductal, 4 patients (9.5%) had lobular, and 17 patients (40.5%) had low-grade disease. Among patients eligible for radiation omission, 34 (72.3%) patients received adjuvant radiation. Those who received radiation were significantly younger than those who did not (74 y, interquartile range = 4 y, versus 78 y, interquartile range = 11 y, P = 0.03). There was no difference in radiation use based on size (P = 0.4), histology (P = 0.5), grade (P = 0.7), race (P = 1), ethnicity (P = 0.6), institution (P = 0.1), gender of the surgeon (P = 0.7), or surgeon (P = 0.1). CONCLUSIONS:Fewer than 10% of patients undergoing breast conservation met criteria for radiation omission. Nearly three-quarters received radiation therapy with younger age being a driver of radiation use, suggesting ample opportunity for de-escalation, particularly among younger eligible patients.

Presented here is a brief discussion on the imperative need and thoughtful approaches to embracing diversity, equity and inclusion within scientific enquiry.

Background: The proportion of laparoscopic pancreaticoduodenectomy (LPD) has increased compared to open pancreaticoduodenectomy (OPD) for resection of pancreatic head malignancies. This study aims to compare the perioperative outcomes and readmission data between OPD and LPD using a large nationwide database. Methods: The Nationwide Readmissions Database (NRD) was queried from 2010-2014 for patients with a diagnosis of pancreatic malignancy who underwent LPD or OPD. Demographics and perioperative outcomes were compared by approach (LPD vs. OPD). Propensity score-matched analysis was performed on a 1:1 match for demographics, Charlson Comorbidities, and 45 additional diagnoses. Results: 22,049 patients with pancreatic malignancies were identified (66±11 years). 2,239 (10%) underwent LPD, and 19,810 (90%) underwent OPD. Utilization of LPD increased over the study period from 2010 (9%) to 2014 (13%), p<0.001. Propensity score matching yielded 1908 patients, with equal proportions undergoing LPD and OPD. Those undergoing OPD experience higher rates of endotracheal intubation, post-operative infections, longer hospital lengths of stay, and higher mortality (Table 1). The overall readmission rate was 20% within 30 days and 36% within the year after surgery. There was a significant difference in the readmission rate between LPD and OPD (20% vs. 25% and 36% vs. 43%, both p<0.01). Those undergoing OPD were more likely to be readmitted with infections and ongoing/new gastric dysfunction (Table 1). Conclusions: National utilization of laparoscopic pancreaticoduodenectomy has increased and it is associated with fewer post-operative complications. Laparoscopy appears to be a safe alternative in those requiring pancreaticoduodenectomy for pancreatic cancer.

Abstract BACKGROUND: It is known that breast cancer subtype (e.g., luminal vs. triple negative (TN)) can affect response to systemic therapy and prognosis; however, it is less well-understood whether these subtypes affect margin status and should therefore alter surgical management. METHODS: Data from two randomized trials evaluating cavity shave margins (CSM) on margin status in patients undergoing partial mastectomy (PM) were used for this analysis. The data were restricted to patients who had invasive carcinoma present in the PM specimen, and in whom data for all three receptors (ER, PR and HER-2) were known. Patients were classified as luminal if they were ER and/or PR+, HER-2 enriched if they were ER and PR negative but HER-2 positive, and TN if they were negative for all three receptors. We evaluated the impact of subtype on the margin status at the time the surgeon had completed their standard PM, prior to randomization to CSM vs. no CSM. Non-parametric statistical analyses were performed using SPSS Version 26. RESULTS: 350 patients were included in this cohort for analysis. The median patient age was 64 (range; 32-94 years) and the median invasive tumor size was 1.2 cm (range; 0.6-8.0 cm). 326 (93.1%) were luminal type, 22 (6.3%) were triple negative, and 2 (0.6%) were HER-2 enriched. Subtype was significantly correlated with race (black patients were more likely to have TN disease than white patients, 22.2% vs. 3.8%, p=0.001), palpability (TN tumors were more likely to be palpable than luminal cancers 54.5% vs. 29.8%, p=0.007) and grade (78.9% of TN cancers were high grade vs. 13.5% of luminal cancers p<0.001). Subtype did not correlate with Hispanic ethnicity, node positivity, nor lymphovascular invasion (p>0.05 for all). While patients with TN and HER-2 enriched tumors were more likely to receive neoadjuvant therapy, this did not reach statistical significance (p=0.117). Surgeons were no more likely to take selective margins on the basis of molecular subtype (p=0.413). In this cohort, the overall positive margin rate was 33.7%. This did not vary based on molecular subtype (positive margin rate: 33.7% for patients with luminal tumors vs. 36.4% for those with TN tumors, p=0.425). On multivariate regression controlling for molecular subtype, race, grade and palpability, the only factor which predicted positive margin status was grade (p=0.005), with high grade tumors being significantly more likely to have a positive margin than low grade tumors, independent of other factors (OR=3.503, 95% CI: 1.638-7.494, p=0.001). CONCLUSION: While molecular subtype correlates with race, tumor grade and palpability, it does not predict margin status. Therefore, molecular subtype should not, independent of other factors, influence surgical decision-making. Citation Format: Andrew Fenton, Elisabeth Dupont, Theodore Tsangaris, Carlos Garcia-Cantu, Marissa Howard-McNatt, Akiko Chiba, Adam Berger, Edward Levine, Jennifer Gass, Kristalyn Gallagher, Sharon Lum, Ricardo Martinez, Alliric Willis, Sonali Pandya, Eric Brown, Amanda Mendiola, Mary Murray, Naveenraj Solomon, Maheswari Senthil, David Ollila, David Edmonson, Melissa Lazar, Jukes Namm, Fangyong Li, Meghan Butler, Noreen McGowan, Maria Herrera, Yoana Avitan, Brian Yoder, Laura Walters, Tara McPartland, Victor Haddad, Hongwei Ma, Ming Xie, Anees Chagpar. Does breast cancer subtype impact margin status in patients undergoing partial mastectomy? [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-15.

Objective: To demonstrate a minimally-invasive method for excision of retrocrural masses. The patient was a 31-year-old male with mixed germ cell testicular cancer underwent left radical orchiectomy, chemotherapy, and open extraperitoneal retroperitoneal lymph node dissection (eRPLND), presented with recurrent disease two years later. Surveillance imaging demonstrated three enlarging retrocrural masses in the setting of normal tumor markers. Methods: The patient was placed in a reverse Trendelenburg position. The liver was retracted. Laparoscopic abdominal inspection demonstrated no adhesions as a benefit of his prior eRPLND. The da Vinci XI robot was docked, the gastrohepatic ligament and short gastric vessels were identified and divided. The stomach and gastro-esophageal junction were identified. The esophagus was mobilized at the level of the diaphragmatic crura before being retracted anterolaterally. The peritoneum was dissected and the diaphragmatic crura was split longitudinally. The larger mass was dissected off of the vena cava and aorta. Lumbar vessels and lymphatics were clipped. Additional inferior dissection was performed to excise the remaining two masses that were adjacent to the celiac artery. The diaphragmatic hiatus was repaired with interrupted sutures. Following closure, esophagogastroduodenoscopy identified viable esophageal mucosa without stricture or evidence of perforation. A drain was placed in the retrocrural fossa. Estimated blood loss was 50 mL. Results: Expected small bilateral pneumothoraces resolved by postoperative day (POD) 2. The drain was removed and the patient was discharged home on POD 2. Final pathology demonstrated metastatic mature teratoma in 3 of 3 nodes with the largest tumor measuring 4.4 cm. The patient has since continued surveillance with no evidence of disease. Conclusions: This video demonstrates the surgical benefits of eRPLND in facilitating reoperation in the abdomen. Furthermore, this video ultimately demonstrates an innovative, minimally-invasive method of removing teratomatous tumors from the retrocrural space through a robotic transabdominal approach.