OBJECTIVE:Synovial sarcoma usually presents with spindle cell morphology with or without epithelial differentiation. Extensive rhabdoid differentiation is a very rare feature with only few cases described in literature. CASE REPORT:We present two cases of synovial sarcoma with rhabdoid differentiation along with their clinical follow-up. Both cases had tumor in the vicinity of joints and showed lung metastasis during follow-up inspite of R0 resection. CONCLUSION:We emphasised that extensive rhabdoid differentiation can be deceptive and challenging for diagnosis in small biopsies and also show an aggressive clinical course with dismal prognosis. Awareness of this rarely described unusual and aggressive histomorphological subtype is prudent due to its distinct diagnostic, prognostic and therapeutic implications.

TPS3161 Background: Mucin 1 (MUC1) is a transmembrane glycoprotein overexpressed in advanced epithelial malignancies, where it promotes tumor progression and correlates with poor clinical outcomes. The membrane-proximal SEA domain of MUC1 is exposed on tumor cells and undergoes rapid internalization, enabling targeted intracellular delivery of cytotoxic payloads. SBO-154 is a MUC1 SEA–directed antibody–drug conjugate (ADC) conjugated to the clinically validated cytotoxic payload monomethyl auristatin E (MMAE) via a protease-cleavable linker. Unlike the shed MUC1-VNTR that creates an antigen sink limiting efficacy of prior ADCs, the negligibly shed MUC1-SEA epitope enables more effective SBO-154 tumor targeting. Nonclinical studies of SBO-154 showed MUC1-dependent cytotoxicity, dose-dependent tumor inhibition in vivo, and a favorable safety for clinical evaluation. This first-in-human study is designed to evaluate the safety, tolerability, pharmacokinetics (PK), immunogenicity, and preliminary antitumor activity of SBO-154 in subjects with locally recurrent or metastatic solid tumors who have exhausted or are intolerant to available therapies. Methods: This phase 1, open-label, multicenter study comprises two parts: dose escalation (Part 1) and dose expansion (Part 2). Eligible adults (≥18 years) must have RECIST v1.1–measurable, locally recurrent or metastatic solid tumors (excluding sarcoma), documented progression after or intolerance to standard therapy, ECOG performance status 0–1, adequate organ function, and tumor tissue for immunohistochemistry (IHC) analysis. SBO-154 will be administered as an intravenous infusion on Day 1 of each 21-day treatment cycle (Q3W) over 30 minutes. Part 1 will use an mTPI-2 design with intra-patient dose escalation from 0.3 mg/kg to 2.5 mg/kg. Approximately 75 subjects will be enrolled in Part 1 (~50 in dose escalation and ~25 in backfill cohorts), and up to 102 subjects in Part 2. After determining the maximum tolerated dose (MTD) and the recommended dose for expansion (RDE), Part 2 will be initiated with a Simon’s two-stage design. Planned expansion cohorts will include NSCLC, ER+ breast cancer, and ovarian cancer, with enrolment to be restricted to tumors with high MUC1-SEA expression. Treatment will continue until disease progression, unacceptable toxicity, or withdrawal from the study. Primary endpoints: include dose-limiting toxicities (DLTs), treatment-related serious adverse events, dose modifications, and clinical/laboratory safety findings. Secondary endpoints: include PK, immunogenicity and efficacy. Enrollment Status: The study initiated enrolment in August 2025. Cohorts 1 and 2 have been completed without any DLTs, and enrolment in Cohort 3 is ongoing as of December 2025. Clinical trial information: NCT07042100 .

Introduction Desmoid-type fibromatosis (DTF) is a rare mesenchymal tumor characterized by high local recurrence and no metastatic potential, with sporadic cases often linked to CTNNB1 gene mutations. While global studies have detailed the frequency and prognostic significance of these mutations, there remains a significant lack of large-scale mutational profiling data from the Indian subcontinent. This study aims to address this knowledge gap by providing the first molecular description of CTNNB1 mutational subtypes in an Indian DTF patient population. Objective The aim of the study is to characterize the CTNNB1 exon-3 mutational profile in Indian patients with DTF and to evaluate its association with key clinicopathological features and treatment outcomes. Materials and Methods This retrospective analysis included formalin-fixed paraffin-embedded (FFPE) tissue blocks from 38 histopathologically confirmed DTF patients treated at a single tertiary center in India between January 2021 to April 2025. DNA was extracted from each of these patients, and exon-3 of the CTNNB1 gene was amplified using polymerase chain reaction, followed by bidirectional sequencing for mutation identification. Histopathological diagnoses were independently validated by two sarcoma pathology experts. Clinical data, including demographics, tumor characteristics, and treatment outcomes, were collected from medical records. Results The cohort included 38 patients (24 women, 14 men; median age 29.5 years, range 7-59). CTNNB1 mutations were present in 23 patients (60.5%). Extremities (36.8%) and the abdomen (34.2%) were the most common tumor sites, with a median baseline tumor diameter of 7.95 cm. Among mutation-positive cases, T41A was most frequent (60.9%), followed by S45F (30.4%) and S45P (8.7%). Fifteen patients (39.5%) had CTNNB1 wild-type tumors. Surgery was the most common initial treatment (15/38). Recurrence occurred in 17 of 29 surgically treated patients (58.6%), including 5 of 7 (71.4%) with S45F mutations. In later treatment lines, active surveillance (50%) and sorafenib (42.1%) predominated. Overall, 26 patients (68.4%) achieved disease control. Conclusion This study offers initial insights into CTNNB1 mutations in Indian DTF patients, revealing a higher frequency of the wild-type gene compared with international data. This finding suggests potential regional differences in disease characteristics. Therefore, further extensive, multi-center studies with long-term follow-up are essential to fully understand DTF in the Indian population, which will be crucial for developing more precise diagnostic methods and effective treatment strategies tailored to this specific demographic.

Round cell sarcoma with EWSR1::PATZ1 fusion is an extremely rare sarcoma of soft tissue and bones that comes under EWSR1::non-ETS fusion sarcoma. Molecular studies, such as next-generation sequencing, are essential for accurate diagnosis, as this tumor presents as conventional round cell sarcoma, often co-expressing myogenic and neurogenic markers, which can prompt an erroneous diagnosis of rhabdomyosarcoma (RMS) or malignant peripheral nerve sheath tumor. Due to the rare incidence and paucity of literature on this tumor, the definite prognostic implications and therapeutic guidelines are lacking. Here, we describe two patients with EWSR1::PATZ1 sarcoma, of which one patient was initially misdiagnosed as synovial sarcoma and RMS on two occasions. These patients underscore the diagnostic challenges and therapeutic uncertainties surrounding EWSR1::PATZ1 fusion sarcomas, emphasizing the need for further large collaborative studies to establish optimal prognostic implications and management strategies for this rare entity.

PURPOSERadiation-associated sarcomas (RAS) are rare tumors developing in previously irradiated areas. Most data come from high-income countries, with limited reports from low- and middle-income countries (LMICs). To our knowledge, this is the largest RAS cohort from India, examining clinical features, genetic predisposition, systemic therapies, and outcomes, in a resource-limited setting.MATERIALS AND METHODSWe conducted a retrospective analysis of a sarcoma database at AIIMS, New Delhi, from January 2015 to June 2025. Patients ≥18 year with biopsy-confirmed RAS, meeting modified Cahan criteria, were included.RESULTSTwenty-three patients (0.32% of 7,138 sarcoma cases evaluated) were diagnosed with RAS. The median age at diagnosis was 51.1 years, with a median latency of 13.25 years following radiotherapy. Breast cancer was the most common antecedent malignancy (21.7%). Soft tissue sarcomas were predominant (14, 60.9%), with undifferentiated pleomorphic sarcoma (8, 34.8%) being the most frequent histologic subtype. At presentation, 12 patients (52.2%) had metastatic disease, while three (13.1%) had locally unresectable tumors. The majority of tumors were high-grade (20, 87.0%), with a median tumor size of 6.9 cm. Among eight patients with resectable disease, seven underwent surgery, achieving R0 resection in 62.5% of cases. Re-irradiation was performed in three patients (13.0%). Sixteen patients (69.6%) received systemic therapy: 12.5% had partial response, 25% had stable disease, and two patients on immunotherapy had progressive disease. At a median follow-up of 68.2 months, the median overall survival was 59.2 months and 13.4 months for patients with nonmetastatic and metastatic disease, respectively.CONCLUSIONDespite large, high-grade, and advanced tumors, curative surgery was feasible in most nonmetastatic cases, and systemic therapies were widely used. The favorable survival outcomes underscore the importance of centralized, multidisciplinary sarcoma care in LMICs. Lack of immunotherapy responses calls for investigation into resistance mechanisms and histology-specific treatments.

Introduction Cancer is one of the leading causes of mortality in India with a crude rate of 100.4/100,000. Sarcomas, despite being rare cancers, are a deadly class of cancers. Scant previous studies have assessed stress, coping strategies, and quality of life (QOL) among rare and more debilitating forms of cancers like sarcomas. Objective (1) To assess the perceived stress, coping strategies, and QOL of sarcoma survivors. (2) To determine the association of perceived stress, coping strategies, and QOL with selected demographic variables, i.e., age, sex, education, occupation, and marital status. Materials and Methods This descriptive cross-sectional study was undertaken at the Sachin Sarcoma Society, New Delhi, between February and May of 2024 and enrolled 130 sarcoma survivors, aged 18 to 55 years. Stress was assessed via the Perceived Stress Score (PSS), coping strategies via Brief-COPE, and QOL via the EORTC QLQ-30 (European Organization for Research and Treatment of Cancer Core 30 Quality-of-Life Questionnaire) scale. We also collected information on socio-demographic characteristics. Besides descriptive summary statistics, we provide chi-square-based results comparing the former among socio-demographic characteristics. Results Majority (59.2%) of the participants were aged 26 to 44 years, and the majority were females, with 43% having a graduate degree, and 90% did not have a family history of cancer. Over 90% of the study sample had moderate stress and approximately 7% had severe stress as per the PSS scale. Means of moderate and high stress levels ranged from approximately 20 to 31. On average, the mean for Brief-COPE domains was over 18 and the functional domain of QOL score had a mean of approximately 56 and the symptom domain had 16. Gender was significantly associated with the Brief-COPE score (chi-squared statistic = 4.52, p = 0.03). Conclusions Moderate stress and a decreased QOL were indicated by the majority of sarcoma survivors. Coping mechanisms vary by gender, which emphasizes the need for specialized psychological therapies. Further longitudinal research is necessary to determine the temporal relationships among sarcoma diagnosis, stress, coping, and QOL outcomes.

Capicua transcriptional repressor ( CIC )-rearranged sarcomas are exceedingly rare and highly aggressive malignancies affecting young individuals predominantly, and CIC::NUTM1 is thought to be a molecular variant of CIC-rearranged sarcoma. It has a poor prognosis and a rapid progression. Here, we present a case of a 3-year-old male with CIC::NUTM1 sarcoma of the pelvis who presented with complaints of constipation associated with severe pain for which 18 F fluorodeoxyglucose positron emission tomography/computed tomography was done as a part of diagnostic workup.

Inflammatory myofibroblastic tumors (IMT) are mesenchymal neoplasms of intermediate malignant potential, characterized by recurrent gene fusions in potentially targetable receptor tyrosine kinases. Primary thoracic IMTs are rare, and their molecular landscape remains incompletely characterized. A ten-year retrospective (2014-2024) clinicopathological analysis of primary thoracic IMTs was done. Histomorphological evaluation and molecular characterization by a graded approach incorporating immunohistochemistry, fluorescence-in-situ hybridization, multiplex reverse-transcription polymerase chain reaction, and next-generation targeted panel sequencing were performed for the common implicated driver fusions. Thirty IMTs involving the lung (n=17), tracheobronchial tree (n=12), and pleura (n=1) were identified. Median age at diagnosis was 18 years (range: 2 to 51 years), including 14 paediatric and 16 adult patients. Male: female ratio was 2.2:1 and 1.3:1, in adults and children, respectively. Majority (22/30, 73.3%) showed cellular spindle-cell pattern with lymphoplasmacytic inflammation. None showed significant atypia, necrosis, or mitotic activity. Molecular characterisation achieved in 22/30 cases revealed 73.3% (16/22) ALK-IMTs, 23% (5/22) ROS1-IMTs, and a single NTRK3-IMT. No statistically significant differences were seen among molecular subgroups, although ALK-IMTs were diagnosed at a higher median age (24.5 years) as compared to ROS1-IMTs (15 years). On follow-up (median follow up period: 24 months), local recurrence was observed in 23% (3/13) patients, all harbouring ALK-IMTs, one of whom was successfully treated with ALK inhibitor therapy; no disease-related deaths were recorded. Primary thoracic IMT affects children and young adults. Majority are driven by ALK gene rearrangements, followed by ROS1 alterations, underscoring role of molecular profiling in potential therapeutic stratification.

Background : Giant cell tumor of bone (GCTB) is typically benign, but a small subset develops malignant GCTB (MGCTB), arising either de novo (primary) or after prior benign disease (secondary). This study presents real-world outcomes of systemic treatment in MGCTB. Methods: We retrospectively analysed adults (≥18 years) with histologically confirmed primary or secondary MGCTB treated at our tertiary sarcoma clinic (2018–2025). Diagnosis was based upon expert pathology opinion and H3F3A IHC. Clinical, pathologic, treatment, and response data were collected and analysis was done using SPSS v.30. Results: Twenty patients (median age 41 years, 65% male) were analysed: 7 (35%) PMGCTB and 13 (65%) SMGCTB (median latency 84 months). Tumours were mainly appendicular (70%), most often distal femur (45%). Around half (8/20; 40%) were metastatic at presentation, mostly to lung. Most common histology was osteosarcoma and UPS. Local control was achieved with wide excision (12/15, 80%), amputation (1/15, 7%), intralesional surgery (2/15 13%). 18 patients (90%) received systemic therapy (median 5 cycles, predominantly doxorubicin-based (16/18, 88%). Neoadjuvant chemotherapy induced responses in 2/3 patients, allowing R0 resection. In the adjuvant group (n=6), only 2 patients remained disease free at the end of follow up. In the palliative chemotherapy cohort (n=7) responses were limited (2 PR, 1 SD). Pazopanib (n=8) produced clinical benefit in 4 patients(50%). Subsequent lines (gemcitabine–docetaxel, eribulin, cisplatin regimens, cabozantinib) showed modest, short-lived activity. The median overall survival was 60 months, with the estimated 12-month OS rate of 65%, and the 60-month OS rate of 42.6%. Conclusions: This study represents one of the largest contemporary real-world evaluation of chemotherapy in MGCTB, providing novel real world insights into response and survival. Systemic therapy and targeted therapy offer modest benefit.

Adrenocortical carcinoma is a rare and clinically heterogeneous malignancy, often posing difficulty in accurate prognostication. Existing clinicopathological scoring systems, the Weiss, AFIP/Wieneke, and Lin-Weiss-Bisceglia (LWB) criteria, are constrained by their age/subtype-specific applicability and are not suitable for evaluating the rare myxoid and sarcomatoid morphologies or needle biopsies. The Reticulin Algorithm (RA) is a simplified approach for the histopathological assessment of adrenocortical neoplasms, but its prognostic utility requires further validation. We evaluated the prognostic performance of RA and its pediatric-adaptation (pRA) in 157 adrenocortical neoplasms, comprising 140 resection specimens and 17 needle biopsies from 118 adult and 39 pediatric patients, representing all histomorphological subtypes. Among adult tumors, the RA demonstrated diagnostic accuracy exceeding 90%, comparable to the Weiss system but with higher specificity and a markedly superior positive likelihood ratio, highlighting its stronger prognostic value. Its greatest impact was observed in oncocytic tumors, where it outperformed the LWB criteria and correctly reclassified most lesions previously designated as having uncertain malignant potential. In pediatric cases, RA’s performance was comparable to the AFIP/Wieneke criteria. Notably, pRA further improved predictive precision. All myxoid and sarcomatoid tumors were appropriately classified using the algorithm. RA application to needle biopsies showed complete concordance with clinical outcomes. Survival analyses confirmed significant stratification between RA-defined benign and malignant groups. In this large single-center study, RA demonstrated broad applicability and prognostic utility across age groups, histologic subtypes, and specimen types, supporting its potential role in risk stratification of adrenocortical neoplasms.

Epstein-Barr virus-associated smooth muscle tumours (EBV-SMTs) are rare neoplasms typically affecting immunosuppressed individuals such as organ transplant recipients. This case follows a woman in her 30s who presented with multi-organ masses 5 years after a kidney transplant. While initial suspicion focused on common post-transplant infections or malignancy, a liver biopsy revealed a smooth muscle neoplasm positive for EBV by EBV-encoded RNA in-situ hybridisation, consistent with EBV-SMT. Managing EBV-SMT is challenging as no standardised treatment regimens exist. When reducing immunosuppression-the conventional first-line approach-failed, a multidisciplinary team opted for a non-standard regimen including Valganciclovir and Pazopanib, which is not a recognised therapy for this condition. The patient achieved a partial metabolic response and maintained stable disease at a 2 year follow-up. This case emphasises the importance of considering this differential when encountering spindle cell neoplasms in an immunosuppressed setting while highlighting the necessity of establishing standardised treatment guidelines for this rare disease.

We recently characterized the microenvironment of Anaplastic Thyroid Carcinoma (ATC) as immune-exhausted, rich in TIM-3-expressing exhausted cytotoxic T lymphocytes (CTLs). PD-1 was notably the least frequently expressed immune checkpoint (ICP). The results provided a potential explanation for the limited efficacy of anti-PD-1/PD-L1 immunotherapy, highlighting TIM-3 as another promising target. This pilot study further evaluated the potential efficacy of targeting TIM-3 in ATC as a therapeutic strategy in an in vitro model. A co-culture model of ATC cell line 8505C with exhausted TIM-3+ve/PD-1+ve CTLs was established and treated with anti-TIM-3 and anti-PD-1 antibodies, alone and in combination. Antibody efficacy was evaluated using flow cytometry, measuring Granzyme B and Perforin for CTL cytotoxic activity, and Annexin V and propidium iodide for tumor cell death. Additionally, differential gene expression before and after ICP blockade was analyzed using the NanoString nCounter Immune-oncology panel. Both individual and combined antibody treatments enhanced CTL cytotoxicity and promoted tumor cell death. Interestingly, ICP inhibition induced an upregulation of immune-activating pathways and downregulation of genes associated with tumor progression. These findings support the potential of TIM-3 blockers as an alternative to or in combination with anti-PD-1 therapy, thereby providing a rationale for further clinical investigation.

Beyond third-line therapy, options for metastatic/advanced GIST are limited, especially in low- and middle-income countries (LMICs) where access to fourth-line ripretinib is often restricted. Cabozantinib, a multi-kinase inhibitor targeting KIT and related resistance pathways, could serve as a pragmatic alternative. This Phase II study evaluated the efficacy and safety of cabozantinib in patients with metastatic/advanced GIST who had progressed after ≥ 3 prior Tyrosine Kinase Inhibitors (TKIs). This is a single-arm phase II trial that enrolled patients with advanced GIST who had progressed on ≥ 3 TKIs with ECOG PS 0–2. Cabozantinib was given orally at 60 mg daily (40 mg if < 40 kg and/or ECOG PS 2). The primary endpoint was 3-month Progression Free Rate (PFR) by RECIST v1.1. Overall Response Rate (ORR) was assessed by RECIST v1.1 and Choi Criteria. Quality of Life (QoL) was done by EORTC-QLQ-C30. Using Ahern’s single-stage phase II design, the trial tested whether cabozantinib could achieve a 3-month PFR of at least 25

INTRODUCTION:The SORASTOP study reports long-term outcomes following planned sorafenib discontinuation in responding patients with extremity desmoid-type fibromatosis (DTF). MATERIALS AND METHODS:In this prospective, single-arm phase 2 Simon's two-stage trial, adults with non-progressive, extremity DTF, ESAS pain < 2, after ≥ 12 months of sorafenib were enrolled. Sorafenib was stopped and patients were monitored with MRI, ESAS, and EORTC QLQ-C30, ACE-III. Progression was defined as ≥ 20 % tumour increase or ≥ 10 % increase with ESAS pain score > 5. The primary endpoint was 1-year PFS. RESULTS:33 patients (median age 30 years; 54.5 % female) were enrolled between 2021-2023. At 12 months, 31 (93.9 %) were evaluable; at 24 months, 30 (90.9 %). After 12 months of discontinuation, 4/31 (12.9 %) had PR, 24/31 (77.4 %) SD and 3/31 (9.6 %) PD and at 24 months 8/30 (26.6 %) had PR, 16/30 (53.3 %) SD and 6/30 (20 %) PD (RECIST v1.1). ESAS pain showed a transient rise: pain-free patients (ESAS=0) decreased from 69.7 % at baseline to 35.5 % at 12 months, recovering to 66.7 % at 24 months. Nine patients (27 %) progressed; four required sorafenib re-initiation and five were managed conservatively, all ultimately achieving disease stabilisation. PFS at 12, 24 and 36 months were 90.8 %, 74.5 % and 74.5 % respectively; with median follow-up of 37 months. EORTC QLQ-C30 showed stable global health status and improvements in emotional, physical, and cognitive functioning, with reductions in fatigue and pain. CONCLUSION:Planned sorafenib discontinuation in responding extremity DTF patients is feasible, yields durable disease control, and improves QoL. Patients who progressed were successfully managed with sorafenib re-challenge or observation.

CIC::DUX4 sarcomas are aggressive soft tissue tumours that often mimic Ewing sarcoma but are distinct in their molecular and clinical behaviour. We describe a young adult male initially managed for a presumed primitive neuroectodermal tumour, later confirmed to have a CIC::DUX4 fusion-positive sarcoma through fluorescence in situ hybridisation and NGS analysis. Despite initial response to Ewing-like chemotherapy (vincristine, doxorubicin and cyclophosphamide regimen), the disease rapidly progressed with widespread visceral metastases, including lungs, spleen, kidneys and soft tissues, eventually leading to death. This case highlights the diagnostic challenges posed by CIC::DUX4 sarcomas, their poor response to conventional chemotherapy and the need for early molecular characterisation to guide prognosis and management. Increased awareness and tailored therapeutic approaches are critical in improving outcomes for this molecular subtype.

9544 Background: BCD-217-2/OCTAVA is an international, multi-center, randomized, double-blind, placebo-controlled phase III study conducted to assess the efficacy and safety of nurulimab +prolgolimab (nuru + prolgo ) combination therapy with continued prolgolimab therapy compared to prolgolimab monotherapy at the 1st line treatment of patients (pts) with unresectable or metastatic melanoma (un/mM). BCD-217 is a fixed-dose combination of nurulimab (aCTLA-4, 5 mg/ml) and prolgolimab (aPD-1, 15 mg/ml) which was recently approved for this indication in Russia and Belarus. Here we present efficacy results based on 24 mos of therapy. Methods: Treatment-naïve pts with un/mM (stage IIIC–IV) were randomized 1:1 to two arms. The nuru+prolgo arm received a combo of nurulimab (1 mg/kg) and prolgolimab (3 mg/kg) at 0.2 ml/kg Q3W for the first four infusions. The prolgo arm received prolgolimab monotherapy (3 mg/kg Q3W) for the first four infusions. Both arms then received prolgolimab maintenance therapy for up to two years. The primary endpoint of the study was PFS. Results: 271 pts were randomized to nuru+prolgo (n=135) or prolgo monotherapy (n=136) arms. After a median follow-up of 24.7 mos the mPFS was 15.4 (95% CI 8.4; NA) mos in the nuru+prolgo arm and 8.3 (95% CI 4.2; 14.8) mos in the prolgo monotherapy arm (HR 0.696, 95% CI 0.502; 0.965), iRECIST, ITT population). The PFS benefit was consistent per RECIST 1.1 (HR 0.717, 95% CI 0.533; 0.964). ORR, DCR and TTR were also higher in nuru+prolgo arm. mOS was not reached in both groups (HR 0.836, 95% CI 0.495; 1.41). 24-mos OS was 76.1% in nuru+prolgo arm and 71.7% in prolgo arm respectively. The mDOR was also not reached in any arm, meaning that more than half of the pts who responded to therapy maintained their response until the end of the FU period. Grade ≥3 treatment-related AEs occurred in 17.8% of pts (nuru+prolgo) vs 13.2% (prolgo). Gr ≥3 irAEs were 14.1% vs 5.1%, respectively (p=0.0126). Any-grade irAEs were reported in 51.9% vs 33.8% of cases (p=0.0027). Treatment discontinuation due to AEs was 11.1% vs 5.1%. Conclusions: The OCTAVA trial results demonstrated a statistically significant and clinically meaningful improvement in PFS for the 1st line low-dose nuru + prolgo combination followed by prolgo maintenance, compared to prolgo monotherapy, in patients with unresectable or metastatic melanoma. This efficacy benefit was accompanied by manageable rate of immune-related AE, consistent with the known profile of CTLA-4/PD-1 combinations. These results support the use of the nuru + prolgo regimen as a valuable 1st line treatment option for this population. Clinical trial information: NCT05732805 .

Introduction Data on systemic therapy for metastatic malignant phyllodes tumor (MPT) are limited. Objective To report the clinical characteristics and outcomes of patients with advanced MPT treated at a tertiary care center in North India. Materials and Methods We retrospectively analyzed patients with advanced MPT (metastatic or unresectable locally advanced) registered between January 2015 and July 2021. Systemic therapies included ifosfamide plus doxorubicin (IA), single-agent doxorubicin, cisplatin plus etoposide, and pazopanib. Tumor response was assessed radiologically using RECIST version 1.1 criteria. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using the log-rank test. Results Fourteen patients (median age, 33.5 years) were included; 12 (86%) had metastatic disease. The median follow-up was 19 months. IA achieved a partial response in 4 of 6 (67%) patients, whereas no responses were observed with single-agent doxorubicin, pazopanib, or cisplatin plus etoposide. Median first-line PFS was 3 months overall and 4 months with IA. Median OS was 20 months. Conclusion IA demonstrated activity in advanced MPT, whereas pazopanib and other regimens showed limited efficacy. Larger studies and multicentric registries are needed due to the rarity of this tumor.