High control rate for lymph nodes in cervical cancer treated with high-dose radiotherapy using helical tomotherapy.

The purpose of this study was to evaluate whether bulky lymphadenopathy located in the abdominopelvic cavity in cervical cancer can be controlled without severe toxicity by increasing radiation dose using helical tomotherapy. From January 2007 to December 2010, 26 patients with cervical cancer with metastatic lymph nodes (LNs) having at least one short diameter > 1.5 cm were treated with helical tomotherapy. A total of 58 LN sites were treated and the largest LN of each site was evaluated for response. Median follow-up time was 28 months (4-50 months). Median short diameter of the LNs was 1.7 cm (0.7-4.2 cm) with median radiation dose of 62.6 Gy(10) in 2 Gy equivalent dose (53.3-77.9 Gy(10)). Initial LN response was evaluated on imaging obtained within 4 months after radiotherapy. Initial complete response (CR), partial response (PR), and stable disease (SD) were observed in 54, 2 and 2 lesions, respectively. Recurrence occurred in two with CR and progression in one with PR. Therefore, final CR, PR, SD, and progression of disease were observed in 52, 1, 2, and 3, respectively. Actuarial 3-year LN progression-free survival and overall survival (OS) were 63% and 65%, respectively. Multivariate analysis revealed final LN response (CR vs. non-CR) as a strong prognostic factor for OS (p = 0.016). Radiation Therapy Oncology Group grade 2 or more acute and late toxicity was observed in 8 and 1 patients, respectively. The treatment of bulky lymphadenopathy using helical tomotherapy in advanced cervical cancer is highly effective and has acceptable toxicity.