The desmoid tumour: local control after surgical treatment.

Desmoid tumours are uncommon non-malignant tumours that show a locally aggressive growth pattern and a high local recurrence rate after surgery. Approximately 10% of the desmoid tumours are associated with familial adenomatous polyposis (FAP). Variable natural history of the disease challenges treatment decision-making in the absence of prospective, randomised data. Association of this rare tumour to GIST is speculated and the tumorigenesis may share common steps. This study reviews given treatment and reports prognostic factors for local control and concurrent neoplasms in patients evaluated by a single soft tissue tumour group. Patients referred to the soft tissue tumour group at Helsinki University Central Hospital (HUCH) for a desmoid tumour (primary or recurred) during 1987-2007 and receiving surgical treatment with or without adjuvant treatment were included in this retrospective review. All locations and also patients with a FAP-associated tumour were included. Extra-abdominal location showed lower local control despite the fact that 27% of patients also received radiation therapy. One amputation was performed. Female sex and location in the rectus abdominis muscle predicted improved local control in multivariate analysis. In this review, the occurrence (14%) of concurrent neoplasms was higher than expected with unusual tumour types noted including two GISTs. In those patients in whom surgical treatment is chosen, adjuvant radiation therapy should also be considered in order to decrease morbidity from aggressive surgery aiming at R0 resection. Further studies are suggested to illuminate the biological association between the desmoid tumour and other neoplasms.