Postoperative radiotherapy in primary resectable desmoid tumors of the neck: a case-control study

Desmoid tumors (DTs) are rare soft tissue tumors, which frequently recur after surgery. The optimal treatment approach is still controversial due to lack of randomized data. The purpose of the study was to review a relative large series of DTs of the neck with emphasis on the value of postoperative radiotherapy (RT).

A total of 68 patients with DTs of the neck region with or without postoperative RT between 1/2008 and 12/2017 were included. They were individually matched for factors including age, gender, tumor size and margin status with a cohort of patients who underwent operative without postoperative RT. The event-free survival (EFS) was compared in the two groups.

For the study, 34 patients and 34 matched control subjects were identified. The two groups did not differ in terms of age (p = 0.810), gender (p = 0.328), tumor size (p = 0.803) and margin status (p = 0.799). Patients who received surgery plus RT had a significantly higher 3‑year EFS than those who received surgery alone (74.6% vs. 13.3%, P < 0.001). Factors including postoperative RT and margin status were independent factors of EFS. The values of P were <0.001 and 0.003 and the hazard ratios (95% confidence interval) were 11.929 (4.732-30.072) and 0.299 (0.133-0.671), respectively. None of the patients treated with RT developed serious complications.

According to our results, postoperative radiotherapy is an effective treatment in desmoid tumors of the neck. Multi-institutional and prospective studies are warranted to further validate our findings.