Prognostic factors and optimal management of desmoid tumors have been discussed for decades. The authors present the results of a large series of patients with desmoid tumors treated at a single institution to investigate the prognostic factors influencing event-free survival (EFS) and suitable treatments for these rare tumors.

Two hundred fourteen patients with desmoid tumors admitted to the surgical department were included, of whom 20 were recommended for a policy of watchful waiting. The following clinical parameters were studied: admission status, age, sex, tumor site, tumor size, margin status, and therapeutic strategy. Univariate and multivariate analysis were performed for EFS.

Forty-two patients had local recurrence. One patient died of intra-abdominal disease. The 5-year and 10-year EFS rates were 78.8% and 77.9%, respectively. In univariate analysis, admission status, tumor site, tumor size, and group (R0 vs R1 and R0 vs R2) had significant impacts on EFS. EFS discrepancy was not significant between R1 and R2 or biopsy groups. In multivariate analysis, tumor size and admission status had independent value. The median delay to progression for patients undergoing watchful waiting was comparable with that for the surgical group.

This study demonstrates that tumor size and a history of recurrence are independent predictors of EFS. Surgery is warranted if it can be R0 and function sparing. Nonsurgical modalities or a policy of watchful waiting may be a better choice for unresectable disease.