Long‐term survivors with desmoplastic small round cell tumor (DSRCT): Results from a retrospective single‐institution case series analysis

OBJECTIVE: To report on a retrospective study of primary DSRCT aiming at characterizing long‐term survivors (LTS). METHODS: All consecutive patients treated at our institution for a primary DSRCT between 2000 and 2021 were retrospectively identified. Patients received multiagent chemotherapy ± surgery ± hyperthermic intraperitoneal chemotherapy (HIPEC) ± whole abdomino‐pelvic radiotherapy (WAP‐RT) ± high‐dose chemotherapy ± maintenance chemotherapy (MC). Event‐free survival (EFS) and overall survival (OS) were estimated by Kaplan–Meier method. Patients alive, without evidence of disease at ≥36 months from diagnosis, were defined as LTS. RESULTS: Thirty‐eight patients were identified. All received multiagent chemotherapy; 27/38 (71%) surgery (7/27 [26%] plus HIPEC), 9/38 (24%) WAP‐RT, 12/38 (32%) MC. At a median‐follow‐up of 37 months (IQR 18–63), overall median‐EFS and median‐OS were 15 and 37 months, respectively. All events occurred within 35 months. In patients who underwent surgery, median‐EFS and median‐OS were 19 and 37 months (23 and 43 months after R0/R1, and 10 and 19 months after R2 resection), respectively. LTS were 5/38 (13%), alive at 37, 39, 53, 64, 209 months. None had liver or extra‐abdominal metastasis at diagnosis, they all received R0/R1 resection, 3/5 had WAP‐RT, 2/5 MC, 1/5 received high‐dose chemotherapy, none HIPEC. CONCLUSIONS: In our series cure was likely achieved in 13% of DSRCT. LTS had no liver/extra‐abdominal disease, were treated with complete surgery, and possibly WAP‐RT/MC.