Cyclic nucleotides in medulloblastomas: correlative study of tumoral and cerebrospinal fluid levels.

The tumoral and cerebrospinal fluid (CSF) levels of cyclic nucleotides and of the main adrenergic metabolites (homovanillic acid and 5-hydroxyindoleacetic acid) were investigated in a group of children with posterior fossa medulloblastomas. A longitudinal evaluation of CSF changes of cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP), and adrenergic metabolites before and after surgical removal of the tumor mass is presented. Some preliminary patterns concerning correlative levels in the neoplastic tissue are discussed. The relevant increase of cGMP in medulloblastoma specimens and in CSF samples before operation and the rapid decrease in the CSF after surgical removal of the tumor seem to suggest a possible role of cyclic nucleotides in the neoplastic growth of these tumors.