The immune status of four men with bowenoid papulosis was evaluated. Each case had been refractory to multiple methods of treatment. Three of the men had other infections and demonstrated a depletion of T4-helper cells. Two of these patients were anergic on skin testing, and the third showed weak reactivity. The fourth patient, who had no evidence of additional infections, had a normal T4 value and T4/T8 ratio, but was anergic on skin testing. All the men were serologically negative for human immunodeficiency virus antibodies. One of the immunosuppressed patients developed squamous cell carcinoma of the tongue, which, along with his bowenoid papulosis, contained human papillomavirus 16 DNA. We suggest that patients with persistent bowenoid papulosis be investigated for altered immune status and followed up as potential candidates for the development of epithelial malignant neoplasms.