Cyclic nucleotide excretion in human malignancies.

1. Urinary cyclic nucleotide excretion was studied in 51 patients with malignant tumours and in 24 control subjects. 2. Adenosine 3':5'-cyclic monophosphate excretion was normal in patients with tumours. 3. Urinary excretion of guanosine 3':5'-cyclic monophosphate was significantly greater than normal in patients with lymphoid tumours (both sexes) and in male patients with myeloid tumours or malignant melanoma. 4. Guanosine 3':5'-cyclic monophosphate excretion was normal in patients with breast carcinoma or colonic adenocarcinoma.