Human papillomavirus (HPV), especially type 16, is causally involved in the pathogenesis of anogenital cancer. There is an increasing number of reports of HPV infections in squamous cell carcinoma (SCC) of the fingers. A search of the Swedish cancer register covering the period 1958-94 inclusive for women with a history of genital and upper extremity SCC revealed 63 cases. Archival material from both cervical and cutaneous lesions was traced and analysed for the presence of HPV DNA in 32 of these patients. A newly developed 'neighbour primer' polymerase chain reaction (PCR) for HPV 16 DNA, aimed at overcoming the obstacle of cross-linked target DNA, was shown to be superior to conventional general and type-specific HPV PCR tests. HPV DNA was significantly more frequently found in digital tumours than in tumours at other cutaneous sites of the upper extremities [67% (10 of 15) vs. 7% (three of 43); P < 0.001]. Among 13 patients with a history of both cervical and finger SCC, HPV 16 was found in cervical samples from seven patients. From five of these seven patients, HPV 16 was also present in the corresponding finger lesions. The results support the hypothesis of a possible transmission of patients' genital HPV infections to fingers.