Postoperative radiation therapy for carcinoma of the uterine cervix

Postoperative radiation therapy (PORT) for cervical cancer has been empirically performed for patients with pathologic risk factors for recurrence after surgery. The efficacy of PORT is mainly supported by retrospective studies. Despite convincing evidence demonstrating a reduction in pelvic recurrence rates when PORT is employed, there is no evidence that it eventually improves patient survival. Local recurrence, such as vaginal stump recurrence, is not always fatal if diagnosed earlier. Some patients, unfortunately, may develop distant metastases even after PORT. The positive effects of PORT also may be counterbalanced by increased toxicities that result from combining local therapies. These factors obscure the efficacy of PORT for cervical cancer patients. There has been no consensus on the predictive value of risk factors for recurrence, which renders indication of PORT for early-stage cervical cancer quite variable among institutions. Today, efforts have been made to divide patients into three risk groups based on the combination of risk factors present after radical hysterectomy. In Europe/USA and Japan, however, a fundamental difference exists in the indications for radical surgery, highlighting differences in the concept of PORT; "adjuvant pelvic irradiation for stage IB-IIA patients after complete resection" in Europe/USA and "pelvic irradiation after surgery irrespective of initial clinical stage and surgical margin status" in Japan. Thus, it is questionable whether scientific evidence established in Europe/USA is applicable to Japanese clinical practice. The purpose of this article is to review the role of PORT by interpreting the results of clinical studies.