Multiple Bowen's disease in a patient with a history of possible arsenic exposure: a case report.

A 81-year-old man with a patch of scaly erythema on his scrotum visited Hiratsuka Kyosai Hospital in June 2006. Reddish, scaly plaques, which were untreated, were present on his back and lower legs since 1999. Pathological examination of the lesions on the scrotum revealed Bowen's disease; therefore he was referred to our clinic for further treatment. During his visit Tokai University Hospital, irregularly bordered scaly erythematous patches were observed on his back, left arm, right knee, and right foot, sizing from 2 to 4 cm in diameter. He was treated with phenol and liquid nitrogen cryotherapy; however, he dropped out of clinic after receiving treatment for a year. At this point, most lesions were cured and only scars remained. In June 2009, he revisited Tokai University Hospital, and this time, multiple scaly erythematous patches were noted on his back and both the arms and legs. The results of the biopsies of 4 lesions obtained from the back, right arm, right knee, and the right foot led to the diagnosis of multiple Bowens' disease. During the inquiry, we learned that since birth, he has resided in Hiratsuka City and had often used water from wells. We researched the possibilities of water and soil contaminations in the Hiratsuka area.