History of whole pelvis plus para-aortic radiation is a risk factor associated with febrile neutropenia during chemotherapy for recurrent cervical cancer.

Radiation-based therapy is widely used for advanced cervical cancer. Prior radiation-based therapy is a potential risk factor for febrile neutropenia (FN). However, the effect of irradiation field size on the incidence of FN during recurrent cervical cancer treatment is unclear. This study aimed to investigate the relationship between prior irradiation field size and FN development during recurrent chemotherapy. This retrospective, observational study included cervical cancer patients who received recurrent chemotherapy between November 2006 and June 2020. The patients were classified into two groups based on the area of irradiation fields. The first group included patients with a history of whole pelvis (WP) irradiation (WP group). The second group had patients who underwent WP plus para-aortic lymph node (PAN) irradiation (WP + PAN group). The incidences of hematological toxicities and FN during the recurrent chemoradiotherapy were compared between the two groups. The FN incidence was significantly higher in the WP + PAN group than in the WP group (32.1% vs. 0%, P < 0.001). The incidence of Grade 4 neutropenia was not significantly different between the WP + PAN and WP groups. The nadir absolute neutrophil counts were significantly lower and the dose reduction or discontinuation rate of chemotherapy was significantly higher in the WP + PAN group than in the WP group. History of WP plus PAN radiation is a risk factor for developing FN during recurrent cervical cancer chemotherapy.