The management of patients with macroscopic or grossly positive para-aortic lymph nodes discovered at the time of surgery or by imaging studies is controversial. It is likely that grossly positive nodes are beyond the ability of radiation therapy alone to sterilize. Therefore, to improve survival, additional therapy is required. In a representative study of the multiple reports in the literature, lymph node metastases were noted in 133 of 266 patients. Pelvic and para-aortic nodes were positive in 44 patients and positive para-aortic nodes were noted in only 2 patients. Five-and 10-year survival rates were similar for patients with macroscopically positive resectable nodes and microscopically positive nodes. Patients with unresectable nodal disease had a worse survival rate than those with resectable disease. All patients underwent extraperitoneal lymph node resections and subsequent radiotherapy. There was a 10% incidence of severe morbidity related to radiation use. Consistent with other reports in the literature, this study showed that extraperitoneal debulking lymphadenectomy confers a survival advantage similar to that enjoyed by patients with micrometastatic disease without additional morbidity (27).
Prophylactic extended-field radiation therapy is an alternative to surgical staging of the para-aortic lymph node chain in women with advanced cervical cancer judged to be at high risk but without radiological or clinical evidence of para-aortic lymph node involvement.
This treatment strategy was evaluated in 441 patients with stages I to III disease (142). High rates of gastrointestinal toxicity were noted in the treatment group. There was no difference in disease-free survival or overall survival between the control and treated groups, although treated patients had fewer para-aortic failures. A lack of difference in survival rates in this study may be related to high local and regional failure rates, suggesting that ideal patients for prophylactic radiotherapy would be those in whom there is a high likelihood of achieving pelvic control. A survival benefit was noted in a study by the Radiation Therapy Oncology Group, in which 367 patients with stages IB to IIB disease were randomized to pelvic radiotherapy versus pelvic and extended field radiotherapy (143). The extended field treatment arm suffered more grade 4 and 5 toxicity, confirming previous studies. Complicating the issue is another study from the Radiation Therapy Oncology Group that revealed that in locally advanced cervical cancer, pelvic radiation therapy with concurrent cisplatin chemotherapy was superior to extended-field radiation therapy (131). The appropriate role of prophylactic para-aortic radiation therapy is still under investigation.
Although not standard practice, the performance of a supraclavicular lymph node biopsy was advocated in patients with positive para-aortic lymph nodes before the initiation of extended-field irradiation and in patients with a central recurrence before exploration for possible exenteration. The incidence of metastatic disease in the supraclavicular lymph nodes in patients with positive para-aortic lymph nodes is 5% to 30% (144). Node enlargement and increased metabolic activity can be assessed with chest PET/CT scanning. Cytologic assessment by FNA can obviate the need for an excisional biopsy and should be performed if any enlarged nodes are present. If the scalene lymph nodes are positive, chemotherapy should be considered.
Complications of Radiation Therapy