Favorable clinical efficacy of cytotoxic chemotherapy in patients with progressive desmoid tumors: a retrospective real-world study.

Background: The real-world evidence about the efficacy of cytotoxic chemotherapy in desmoid tumors is still limited. We investigated the efficacy of chemotherapy in the treatment of recurrent or progressive desmoid tumors.

Methods: The patients with desmoid tumors who had received cytotoxic chemotherapy between November 2007 and June 2020 in two tertiary hospitals in Korea were reviewed.

Results: A total of 25 patients were included in the analysis. The most common primary tumor site was the intra-abdominal or pelvic cavity (56%), followed by the trunk and abdominal wall (24%), extremities (16%), and head and neck (4%). Sixty percent of the patients had familial adenomatous polyposis and 76% received doxorubicin plus dacarbazine. The objective response rate and disease control rate was 64% (95% confidence interval [CI]: 40.7-82.8) and 96% (95% CI: 77.2-99.9), respectively. With the median follow-up time of 55 months (95% CI: 41.0-68.2), the 3-year PFS rate was 65% (95% CI: 41.1-80.5), and the 3-year OS rate was 89% (95% CI: 63.8-97.3). Grade 3 or 4 hematologic adverse events were reported in 14 patients, all of which were manageable.

Conclusion: Our real-world evidence suggests that doxorubicin-based cytotoxic chemotherapy can be an effective treatment option for recurrent and progressive desmoid tumors with respect to favorable clinical outcomes.