"Patients with BM may be at increased risk of developing LM, especially if the BM are located in the posterior fossa (BMPF). Among patients undergoing craniotomy for BMPF, estimates of the risk of developing LM are reported as high as 67%. Recent reports have begun to dissect out the details on the risk of CSF seeding after craniotomy. In a review of 379 patients with BMPF who were treated with either surgical resection or stereotactic radiation, 8.7% developed LM. But, there was a significantly higher risk of LM (14%; rate ratio, 2.45; P = .02) in those patients having a piecemeal resection of their BMPF when compared with either stereotactic radiation or en bloc resection. A follow-up study of 827 patients undergoing craniotomy for supratentorial BM found a similar result, with a hazard ratio of 5.8 (P = .002) comparing piecemeal resection vs stereotactic radiation and a hazard ratio of 2.7 (P = .009) comparing piecemeal resection vs en bloc resection. Patients with BM who undergo piecemeal tumor resection may be a good population in which to test biomarker-based or prophylactic interventions against LM."
New Strategies in the Management of Leptomeningeal Metastases (2010)
http://archneur.jamanetwork.com/mobi...ticleid=799479