Impact of surgical margins on survival in cutaneous sarcomas: A nationwide study of French Sarcoma Group (FSG) from NETSARC Database.

Abstract

e23537 Background: R0 surgery in reference centers is the cornerstone for sarcomas treatment with better local control and survival and is mandatory for ESMO-EURACAN and NCCN guidelines. The medical community is out on this issue for cutaneous sarcomas, if they have to follow suit. This retrospective descriptive study focused on margin status and local relapse-free survival (LRFS) and overall survival (OS) of patients (pts) with cutaneous sarcomas. Methods: Between 01/01/10 and 30/12/17, surgery was performed on 2044 pts with cutaneous sarcomas from 20 centers. Data were collected from the NETSARC national network database ( http://netsarc.sarcomabcb.org ). Diagnosis of cutaneous sarcoma was reviewed and histologically confirmed by a local expert pathologist of RRePS (“Network for expert pathology diagnosis in sarcoma”). Dermatofibrosarcoma, Kaposi sarcoma and rare subtypes (< 20 cases in the database) were excluded. Univariate analyses were conducted using log rank test or Cox test. Multivariate analyses were conducted using Cox test. Age and tumor size were analyzed as continuous values. Two-sided significant p level was set at < 0.05. Results: Mean age was 66 years. Primary tumor was localized in lower limb, trunk wall, head and neck and upper limb for 30%, 26%, 26% and 18% pts respectively. Main subtypes were leiomyosarcoma, undifferentiated sarcoma, and myxofibrosarcoma for 29%, 29%, and 14% pts respectively. Angiosarcoma was the subtype of 9% of the patients (n = 193). Mean size was 45 mm. FNCLCC grade was 1, 2, and 3 for 14%, 29.5%, and 24% tumors respectively. Before surgery, imaging and biopsy were performed for 21% and 51% pts respectively. Surgery was carried out in a NETSARC center for 26% of the pts. Margin status after initial surgery was R0, R1, and R2 for 35% (n = 724), 34% (n = 696), and 12% pts (n = 246) respectively. Re-excision was performed for 34% (703/2044 pts), leading to a subsequent R0 margin for 74% of them (523/703 pts, equivalent to 26% of the overall population). Local relapse occurred for 21% of pts after a median time of 10 months. Metastatic relapse occurred for 13% of pts after a median time of 11 months. One hundred and ninety-three pts (9%) died. Median follow-up was 12 months. In multivariate analyses, statistically significant favorable prognostic factors for LRFS were: young age, small tumor size and non-angiosarcoma subtype. Significant prognostic factors associated with longer OS were: young age, small tumor size, non-angiosarcoma subtype, FNCLCC grade (1 vs 2 and 1 vs 3) and initial R0 surgery. Conclusions: Cutaneous sarcomas share same favorable clinical prognostic factors than non-cutaneous sarcomas. Quality of surgery remains the mainstay for OS.