Hypofractionated short course radiation therapy for recurrent ovarian cancer

• Hypofractionated radiation therapy resulted in promising response rates for recurrent ovarian cancer. • Hypofractionated radiation therapy was well-tolerated with no Grade 3 or Grade 4 toxicities in this cohort. • Hypofractionated radiation therapy is a viable treatment option for recurrent ovarian cancer, particularly among patients with oligometastatic disease. Background: While chemotherapy has largely replaced radiation therapy in upfront treatment of ovarian cancer, radiation has shown potential in the recurrent setting where chemoresistance, toxicities, and patient preferences may limit other treatment options. Hypofractionated radiation therapy (HFRT) is a highly conformal radiation therapy in which higher doses of radiation are delivered per treatment with the goal of fewer treatments. Objectives: To evaluate treatment response and survival for patients with recurrent ovarian cancer treated with HFRT and to evaluate treatment toxicity. Methods: This was a retrospective cohort study of patients who received HFRT for the treatment of recurrent ovarian cancer at a single, large academic institution. Patient demographics, tumor characteristics, and treatment history details of the HFRT were collected via electronic medical record chart review. Outcomes including treatment response, survival and toxicity profile were analyzed. Treatment response was defined by RECIST 1.1 criteria. Toxicities were defined using the Radiation Therapy Oncology Group Criteria. Results: 22 patients were reviewed. 1 patient (4.55%) had a complete response, 8 patients (36%) had a partial response, 7 patients (32%) had stable disease and 3 patients (14%) had progressive disease, and 3 patients (14%) were unevaluable by RECIST 1.1 criteria after treatment with HFRT. Mean progression free survival (PFS) was 11.5 months and overall survival (OS) was 28.7 months. HFRT was well-tolerated with no Grade 3 or 4 toxicities. The majority of patient’s had one to two lesions which were targeted for treatment. Conclusions: For well-selected patients, particularly those with oligometastatic disease, HFRT should be considered as an additional treatment option for recurrent ovarian cancer.