NONCUTANEOUS MALIGNANT-TUMORS IN THE PUVA FOLLOW-UP-STUDY - 1975-1996

There is concern about possible association between PUVA treatment and an increased risk of noncutaneous cancer. An alteration in the risk o f cancer among persons with psoriasis has also been postulated. To tes t this hypothesis, for nearly two decades we have prospectively follow ed 1380 patients who first began PUVA treatment for psoriasis in 1975- 1976. We compare the risk of noncutaneous cancer in our cohort with th at expected based on general population incidence rates. The overall r isk of noncutaneous cancer was nearly identical to that expected in ge neral population. For three separate sites, we noted significant incre ases: thyroid cancer (RR = 3.57, 95% CI = 1.16-8.34), breast cancer (R R = 1.81, 95% CI = 1.19-2.64), and central nervous system neoplasms (R R = 2.80, 95% CI = 1.13-5.57). Since 1987, however, the risk of centra l nervous system neoplasms has not been elevated (RR = 0.00, 95% CI = 0.00-3.35) and the relative risk of breast cancer was lower than in th e prior decade and not statistically significant. There was no associa tion between higher levels of exposure to PUVA and the risk of any of these cancers. We did not detect any significant increase in the risk of lymphoma or leukemia. Our study does not support the hypothesis tha t long-term PUVA treatment increases the risk of noncutaneous cancer.