Phase I study of weekly nedaplatin and concurrent pelvic radiotherapy as adjuvant therapy after radical surgery for cervical cancer.

Nedaplatin is an analog of cisplatin that was developed in Japan, and it exhibits less nephrotoxicity, neurotoxicity, and gastrointestinal toxicity than cisplatin. This study aimed to determine the recommended dose of weekly nedaplatin chemoradiotherapy in high-risk patients following radical surgery. Fifteen patients who required postoperative pelvic radiotherapy after radical surgery for cervical cancer were enrolled in the present study. Nedaplatin was designed to be administered for eight cycles (minimum five cycles) beginning at a weekly dose of 22.5 mg/m(2) and then escalating to 25, 27.5, and then to 30 mg/m(2). Dose-limiting toxicity was defined as a more than 7-day delay in the planned radiation therapy and/or planned chemotherapy (prior to the completion of five cycles) due to toxicity. Nedaplatin administration was interrupted prior to the completion of five cycles in one of six patients at a dose of 27.5 mg/m(2). A more than 7-day delay in the planned radiation therapy did not occur in any patient. Nedaplatin at a dose of 30 mg/m(2) was safely administered, and two of three patients could receive the planned chemotherapy consisting of eight cycles of weekly nedaplatin. Our recommended weekly nedaplatin dose was determined to be 30 mg/m(2) administered for more than five cycles and up to eight cycles if possible. Weekly administration of nedaplatin may be more tolerable and less toxic than weekly administration of cisplatin.