Involved-field radiation therapy for locoregionally recurrent ovarian cancer

Objective To evaluate the effectiveness of definitive involved-field radiation therapy (IFRT) for selected patients with locoregionally-recurrent ovarian cancer. Methods We retrospectively reviewed records of 102 epithelial ovarian cancer patients treated with definitive IFRT (≥ 45 Gy). IFRT was directed to localized nodal (49%) and extranodal (51%) recurrences. Results The median time from diagnosis to IFRT was 36 months (range, 1-311), and the median follow-up after IFRT was 37 months (range, 1-123). Patients received a median of three chemotherapy courses before IFRT (range, 0-9). Five-year overall (OS) and progression-free survival (PFS) rates after IFRT were 40% and 24% respectively; the 5-year in-field disease control rate was 71%. Thirty-five patients (35%) had no evidence of disease at a median of 38 months after IFRT (range, 7-122), including 25 continuously without disease for a median of 61 months (range, 17-122) and 10 with salvage treatment following disease recurrence, disease-free for a median of 39 months after salvage treatment (range, 7-92). Eight clear cell carcinoma patients had higher 5-year OS (88% versus 37%; p = 0.05) and PFS (75% versus 20%; p = 0.01) rates than other patients. Patients sensitive to initial platinum chemotherapy had a higher 5-year OS rate than platinum-resistant patients (43% versus 27%, p = 0.03). Patients who required chemotherapy for recurrence after IFRT often benefitted from longer chemotherapy-free intervals after than before IFRT. Conclusions Definitive IFRT can yield excellent local control, protracted disease-free intervals, and even cures in carefully selected patients. RT should be considered a tool in the curative management of locoregionally-recurrent ovarian cancer.