Carbon-11-methionine PET evaluation of intracerebral hematoma: distinguishing neoplastic from non-neoplastic hematoma.

Abstract

We evaluated whether PET with L-methyl-11C-methionine (11C-methionine) was clinically useful in distinguishing neoplastic from non-neoplastic intracerebral hematoma. We examined eight patients with neoplastic (n = 4) or non-neoplastic (n = 4) intracerebral hematomas between 5 and 68 days after the bleeding episode using PET with 11C-methionine (Met-PET). Carbon-11-methionine accumulated in the area surrounding the hematoma in both groups, except in one patient with an acute hypertensive hematoma. Between 22 and 45 days after the ictus, non-neoplastic hematomas showed increased 11C-methionine accumulation largely in accordance with the contrast-enhanced areas on CT or MR images; whereas between 14 and 68 days after bleeding, neoplastic hematomas showed increased 11C-methionine accumulation that extended beyond the contrast-enhanced areas on CT or MR images. The intensity of 11C-methionine accumulation in tumor tissue was greater than that in non-neoplastic hematomas. Preliminary results suggest that Met-PET can distinguish neoplastic from non-neoplastic hematomas on the basis of differences in lesion extent compared with CT or MR findings.