[Malignant mediastinal lymph node tumors with unknown primary cancers].

PURPOSE: Malignant mediastinal lymph nodes with unknown primary tumor is a rare occurrence. The purpose of this study is to specify some characteristics of the patients presenting with this disease and to define an adequate therapeutic approach.

MATERIAL AND METHODS: Between 1985 and 1997, we have operated on 54 patients with isolated non-small cell malignancy to mediastinal lymph nodes. Forty-nine patients underwent surgical biopsy of the mediastinal mass, generally followed by radiation therapy and/or chemotherapy. A mediastinal lymph node resection was performed in 5 patients.

RESULTS: Five patients were lost to follow-up (9.3%). The 5-year survival rate and the median survival were 12.4 +/- 5% and 7 months respectively. Four of the 7 patients who were still alive after follow-ups ranging from 10 to 68 months had undergone a lymph node resection. During the follow-up, a primary tumor was discovered in only 5 patients (11.4%).

CONCLUSIONS: Patients with isolated malignant lymph nodes of the mediastinum have a poor prognosis. In order to improve their survival, we recommend a more aggressive therapeutic approach comprising a chemotherapy and a mediastinal lymph node resection, associated in some cases with a lung resection. Radiation therapy of the mediastinum can be administered, principally in case of incomplete resection.