Prognostic factors associated with distant recurrence in patients with intimal sarcoma at a tertiary sarcoma referral center in Latin America.

Abstract

e23565 Background: Intimal sarcoma (InS) is an extremely rare and aggressive subtype of soft tissue sarcoma, typically originating in large mediastinal vessels or the heart. This high-grade tumor carries a dismal prognosis, with reported median overall survival (OS) ranging from 8 to 13 months. Molecularly, MDM2 and CDK4 amplifications are hallmark alterations, suggesting potential therapeutic targets. However, data on prognostic factors, therapeutic strategies, and survival outcomes are scarce, particularly in Latin American populations. This study aims to identify prognostic factors associated with recurrence and survival in patients with intimal sarcoma treated at a tertiary sarcoma referral center. Methods: A retrospective cohort study was conducted at a Latin American sarcoma referral center, analyzing patients diagnosed with histologically confirmed intimal sarcoma between 2014 and 2024. Clinical, pathological, and treatment data were collected. Inclusion criteria were a confirmed diagnosis of intimal sarcoma, complete clinical staging, and follow-up information. The primary outcomes were overall survival (OS), progression-free survival (PFS), and recurrence patterns. Kaplan-Meier survival curves were used to estimate OS and PFS, and Cox proportional hazards regression was performed to evaluate prognostic factors. Results: A total of 12 patients (six males, six females) with a median age of 44.6 years (IQR 29-64) were included. Tumor locations included the right atrium (n = 4), pulmonary vein (n = 4), right ventricle (n = 1), and vena cava (n = 1). Six patients presented with early-stage disease (Stages I-II), 1 with locally advanced disease (Stage III), and 5 with metastatic disease (Stage IV). Multimodal treatment was performed in 9 patients, and 7 received anthracycline-based chemotherapy. The median PFS was 14.1 months (IQR 1-48), and the median OS was 19.1 months (IQR 1-52). Recurrence or disease progression occurred in 10 patients, with the most common recurrence sites being the lungs (n = 4), central nervous system (n = 2), and mixed sites (n = 1). No significant difference in OS and PFS was observed based on tumor location, size, or treatment. Conclusions: Intimal sarcoma remains a highly aggressive malignancy with a poor prognosis and high recurrence rates. This study highlights the frequent pulmonary and central nervous system recurrence patterns and emphasizes the critical role of surgical resection in initial disease control. However, recurrence is common, underscoring the need for multimodal approaches, including anthracycline-based chemotherapy, and exploring emerging therapies targeting MDM2 amplifications. These findings provide valuable insights into this rare malignancy in Latin America and reinforce the need for further research to improve outcomes.