[Evaluation of prognostic factors affecting recurrences and disease-free survival in extra-abdominal desmoid tumors].

Objectives: We investigated treatment results and the role of potential prognostic factors in patients treated by surgery with or without adjuvant radiotherapy for primary or recurrent extra-abdominal desmoid tumors.
Methods: The study included 38 patients (23 females, 15 males; mean age 24 years; range 5 to 61 years) who underwent surgical treatment for extra-abdominal desmoid tumors. Of these, eight patients (21.1%) already had recurrences before treatment. Involvement was in the upper extremity in 12 cases (31.6%), in the lower extremity in 22 cases (57.9%), and in the axial region in four cases (10.5%). Twenty-two patients received adjuvant radiotherapy following surgical resection. Survival was analyzed by the Kaplan-Meier method. The mean follow-up period was 7.3 years (2.5 to 228 months).
Results: Twenty patients (52.6%) developed recurrences after treatment. Of these, recurrences were already present in six patients, and adjuvant radiotherapy was administered to 11 patients (55%). Recurrences developed at the irradiated site in eight patients, and in other regions in three patients. The mean disease-free survival was 38+/-8 months, and eight-year disease-free survival was 35.7+/-8.5%. Disease-free survival did not differ significantly between patients receiving adjuvant radiotherapy (47.9+/-7.9 months) and those treated with surgery alone (37.9+/-12.4 months), and between patients who developed a recurrence at the resection site (12.1+/-4.7 months) or at a different site (24.3+/-1.0 months) (p>0.05). None of the potential prognostic factors including gender, age, localization, surgical margin, or adjuvant irradiation were found to affect disease-free survival.
Conclusion: In our series, no prognostic factor could be identified as having an association with the high recurrence rate.