Hemangioblastoma is a benign
tumor of the cerebellum, and treatment involves surgical excision, both as the initial treatment and also in case of recurrence. Recurrence of
hemangioblastoma can be local due to incomplete resection or can be distant and separate from the
tumor resection region. Local recurrence can largely be avoided by verifying for any
residual tumor intraoperatively before closure. In this study, we used intraoperative fluorescent diagnosis using 5-aminolevulinic
acid (5-ALA) to verify the presence of a
residual tumor during surgical resection. Nine patients with
hemangioblastoma were given 1 g of 5-ALA orally before surgery, and a
laser beam of 405 nm was focused on the
tumor during resective surgery. Fluorescence of
protoporphyrin IX (
PPIX) was observed in the core of
tumor in all the cases. Fluorescence of
PPIX was observed in the peritumoral
cyst wall in two patients after
tumor resection, and in both of them fluorescent parts of
PPIX were resected and histological examination showed
tumor cells. Usually, there are no
tumor cells in the peritumoral
cyst of a
hemangioblastoma, yet
hemangioblastomas may sometimes recur from an unresected
cyst wall. It is thus necessary to excise an infiltrating
cyst of
tumor cells to prevent recurrence. Intraoperative fluorescent diagnosis using 5-ALA is a useful method to discern whether
tumor cells are present in the peritumoral
cyst wall of a
hemangioblastoma.