The pathophysiology of Raynaud's phenomenon after Cisplatin-Bleomycin-Vinblastine combination chemotherapy, its relationship to polyneuropathy, and response to transcutaneous nerve stimulation (TNS), was studied in eight patients previously treated for testicular cancer. Peripheral circulation in the index finger was measured by laser Doppler flowmetry before and after cold provocation. In all patients there was an exaggerated and prolonged vasoconstrictor response to cold, with a mean flux reduction of 61%, and a mean restitution time of greater than 7 min, characteristic of Raynaud's phenomenon of the vasospastic type. The normal controls had a mean flux reduction of 24% and a restitution time of 1.5 min. Clinical examination and nerve conduction measurements revealed a mild polyneuropathy in five of the eight patients, but an etiological relationship with Raynaud's phenomenon could not be ascertained. There was no measurable effect of TNS.