Intensity modulated radiation therapy for recurrent ovarian cancer refractory to chemotherapy

• Excellent local control with IMRT for localized recurrent ovarian cancer
• Minimal radiation toxicity despite a heavily pre-treated patient population
• SBRT may be feasible for an appropriately selected patient population

ObjectiveTo evaluate local control, survival outcomes, and toxicity after intensity modulated radiotherapy (IMRT) for recurrent chemorefractory ovarian cancer.MethodsBetween 2006 and 2014, 33 patients were treated with IMRT for recurrent ovarian cancer. Patients received a median of 3 chemotherapy regimens prior to IMRT (range, 1–12) with 11 (33%) undergoing concurrent therapy. Local control (LC), recurrence free survival (RFS), and overall survival (OS) were calculated via Kaplan-Meier method. Toxicity was assessed using the Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Impact of patient characteristics on outcomes was evaluated via Cox's proportional hazard model.ResultsMedian follow up was 23.7 months. Forty-nine sites were treated to a median dose of 5040 cGy (range, 4500–7000). Nine (18%) of the 49 sites had in-field failures. Two year actuarial LC, RFS, and OS were 82%, 11%, and 63%, respectively. Seventeen patients had both a pre and post-treatment FDG-PET/CT; 6 (35%) had a complete metabolic response while 11 (65%) had a partial metabolic response. Acute ≥ grade 3 gastrointestinal (GI) toxicities occurred in 2 (6%) patients, late ≥ grade 3 GI toxicities occurred in 12 (36%), acute ≥ grade 3 hematological toxicities occurred in 5 (15%) and late ≥ grade 3 hematological toxicities occurred in 14 (42%).ConclusionsIMRT for recurrent chemorefractory ovarian cancer is associated with excellent local control and limited radiation related toxicity. Future studies will be required to determine which subpopulation will benefit most from IMRT and whether alternative techniques such as stereotactic body radiotherapy may be feasible.