RT Journal Article T1 Familial adenomatosis polyposis-related desmoid tumours treated with low-dose chemotherapy: results from an international, multi-institutional, retrospective analysis. A1 Napolitano, Andrea A1 Provenzano, Salvatore A1 Colombo, Chiara A1 Vitellaro, Marco A1 Brunello, Antonella A1 Badalamenti, Giuseppe A1 Nannini, Margherita A1 Ibrahim, Toni A1 Hohenberger, Peter A1 Gasperoni, Silvia A1 Gennatas, Spyridon A1 Jones, Robin L A1 Hindi, Nadia A1 Martin-Broto, Javier A1 Spalato Ceruso, Mariella A1 Silletta, Marianna A1 Dei Tos, Angelo Paolo A1 Gronchi, Alessandro A1 Stacchiotti, Silvia A1 Santini, Daniele A1 Tonini, Giuseppe A1 Palassini, Elena A1 Vincenzi, Bruno K1 chemotherapy K1 desmoid K1 familial adenomatosis polyposis K1 methotrexate K1 vinca alkaloids AB Desmoid tumour (DT) is a locally aggressive fibroblastic proliferative disease representing the most common extraintestinal manifestation of familial adenomatosis polyposis (FAP). As data on the activity of chemotherapy in these patients are limited, we examined the outcomes of patients treated with low-dose methotrexate (MTX)+vinca alkaloids (vinorelbine or vinblastine). We retrospectively reviewed clinical and outcome data from all patients with confirmed FAP-associated DTs treated with weekly MTX+vinca alkaloids in seven European sarcoma reference centres between January 2000 and December 2018. Radiological responses were assessed using RECIST V.1.0 and V.1.1. The Kaplan-Meier method associated to the log-rank test was used to estimate and compare survival curves. We identified 37 patients (median age 29 years, range 7-44). According to RECIST, 20/37 (54.1%) patients achieved partial response (PR), 15/37 (40.5%) patients had stable disease and 2/37 (5.4%) had progressive disease as best response. Overall, the median progression-free survival (PFS) was 6.5 years (range, 0.3-12.1 years). In the subset of patients achieving PR as best response, the median PFS was not reached. In a subset of 11 patients with progressive disease offered MTX+vinca alkaloids rechallenge (after chemotherapy withdrawal following prolonged disease control), the disease control rate was 100%, resulting in a median PFS after rechallenge of 5.8 years. This is the largest series on the activity of low-dose chemotherapy in patients with FAP-related DT. In this population, MTX+vinca alkaloids is an active combination, as already reported in patients with sporadic DT. YR 2020 FD 2020 LK http://hdl.handle.net/10668/14969 UL http://hdl.handle.net/10668/14969 LA en DS RISalud RD Apr 8, 2025