Therapeutic approach of cervical lymph nodes metastases of squamous cell carcinoma from an unknown primary tumors

Cervical lymph node metastases of squamous cell carcinoma from occult primary constitute about 3-5% of all patients with carcinoma of unknown primary site (CUP). Identification of subgroups with favorable prognosis is of decisive importance for the therapy of patients with CUP syndrome, including prolonged survival from directed treatment. The patients with neck node metastases from occult head and neck cancer have clinical features and prognosis similar to other head and neck malignancies. Treatment of patients with metastatic squamous cell carcinoma involving cervical lymph nodes of an unknown primary origin should be similar to that of patients with locally advanced carcinoma of the head and neck. Therapeutic approaches include surgery (lymph node excision or neck dissection), with or without post-operative radiotherapy, radiotherapy alone and radiotherapy followed by surgery. In early stages (N1), neck dissection and radiotherapy seem to have similar efficacy, whereas more advanced cases (N2, N3) necessitate combined approaches. The extent of radiotherapy (irradiation of bilateral neck and mucosa versus ipsilateral neck radiotherapy) remains debatable. A potential benefit from extensive radiotherapy should be weighted against its acute and late morbidity and difficulties in re-irradiation in the case of subsequent primary emergence. The role of other methods, such as chemotherapy and hyperthermia, remains to be determined.