Meningeal carcinomatosis in small cell carcinoma of the lung.

Cerebral and meningeal metastases are increasingly important complications in small cell anaplastic carcinoma of the lung. In a study at this institution, 60 evaluable patients received intensive chemotherapy without prophylactic cranial irradiation or other prophylactic measures. The complete plus partial remission rate was 78 percent with a median survival of 49+ weeks (range eight to 106+ weeks) for those with a complete response and 18+ weeks (range six to 67 weeks) for those with a partial response, all of which are comparable to other reported series. In 11 patients (18 percent) meningeal carcinomatosis has developed. Forty-two percent of the patients with a relapse have exhibited meningeal carcinomatosis and in 27 percent of the patients with a relapse it was the only site of relapse. Cerebral metastases occurred in 27 percent of those who had a relapse, and in 12 percent this was the sole site of relapse. Simultaneous meningeal carcinomatosis and cerebral metastases occurred in 8 percent of the patients with a relapse. The median time to meningeal relapse was 27 weeks (range 12 to 60 weeks) compared with 25+ weeks (six to 106+ weeks) over-all, and the median survival was 28 weeks (range 14 to 82 weeks) compared with 25+ weeks (two to 106+ weeks) for the whole group with small cell carcinoma of the lung. Meningeal involvement in small cell carcinoma of the lung must now be considered a sanctuary site of equal importance to cerebral metastases. To prevent and treat this complication will necessitate evaluation of all available modalities, including cranial and spinal irradiation, intrathecal chemotherapy and systemic agents that readily cross the blood-brain barrier.