Clinical outcome of stereotactic body radiotherapy for abdominal lymph node metastases.

Aims and background. To report the clinical outcome of linac-based or robotic, image-guided stereotactic body radiotherapy in patients affected by abdominal lymph node metastases from different primary cancers. Methods and methods. Twenty-six patients with 32 abdominal lymph node metastases were consecutively treated at the University of Florence between April 2011 and May 2012. The mean follow-up was 4.6 months (SD, 3.9; range, 0.3-13). The dose prescription ranged between 24 Gy and 36 Gy delivered in 1-5 fractions. Results. In terms of local control, complete response to stereotactic body radiotherapy was obtained in 18 cases (66.7%), partial response in 7 (25.9%), and stable disease in 2 (7.4%). At the Cox univariate regression analysis, an increased risk of partial response or absence of local response to radiotherapy was found for subjects of the female sex (P = 0.036), age less than 50 years (P = 0.022), primary tumor of the genital tract (P = 0.007), and previous chemotherapy (P = 0.057). An excellent local control rate (90.9%) was obtained in patients affected by abdominal lymph node metastases of prostatic origin. Conclusions. Stereotactic body radiotherapy for abdominal lymph node metastases is a safe and effective treatment in terms of high rates of local control, especially in a subset of patients affected by prostate cancer.