83P Management of alveolar soft part sarcomas in LMICs: Experience from a dedicated sarcoma clinic in North India and challenges

Alveolar soft part sarcoma (ASPS) is a rare, indolent soft tissue sarcoma, with a high predilection for systemic dissemination. This study aims at elucidating the patterns of clinical presentation of ASPS and their treatment outcomes, with emphasis on the efficacy of anti-angiogenesis agents, and the challenges faced in managing these rare tumours in low and middle-income countries (LMICs). This was a retrospective cohort that included patients with advanced ASPS treated at our institute between 2016-2023. Clinicopathological data was obtained from case records, and analysed to assess outcomes. The study included 30 patients (17 males, 13 females) with a median age of 28 (3-72) years (Table). The median time from the onset of symptoms to final diagnosis was 9 (5-15) months. 7 patients presented with localized disease, and 23 with upfront metastatic disease. The most common site of primary was the extremities (73%), and the most common sites of metastasis included the lungs (82%) and bones (21%). Brain metastasis was seen in 6 patients at baseline (26%). 90% of patients with metastatic disease received a tyrosine kinase inhibitor (TKI) in the first-line setting with a median PFS of 12 months. The median OS in this subset was 36 months. 5 patients with advanced disease received immune-checkpoint inhibitors (ICI) (2-atezolizumab, 3 -nivolumab); the 2 patients on atezolizumab continue to be progression free at 12 and 8 months respectively. Patients with brain metastasis were seen to have markedly poor outcomes (median OS 9.4 months vs 56 months). Table: 83PBaseline characteristics of the patientsNumber (%)Male Female17 (56.6%) 13 (43.4%)Median Age (years)28 years (3-72 years)Site of disease Extremity Trunk and viscera Head and neck22 (73.3%) 5 (16.6%) 3 (10%)Localised Metastatic Lungs Brain Liver Bones Non regional nodes7 (23.3%) 23 (76.6%) 19 (82.6%) 4 (26.0%) 3 (13.0%) 5 (21.7%) 2 (8.6%) Open table in a new tab The use of anti-angiogenic agents has significantly improved survival in patients with advanced ASPS in LMICs. Delays in diagnosis and restricted access to immune checkpoint inhibitors represent significant challenges in further improving outcomes. This study represents the largest cohort of patients with advanced ASPS from this region.