Skin cancer caused by grenz rays.

A 30-year-old woman developed chronic radiodermatitis and five squamous cell carcinomas within 7 years following a 16-year period of repeated grenz irradiations given to her psoriasis. The estimated cumulative dose of grenz radiation was approximately 3,000 rads (r) to each treated area. This case, illustrating a rather underestimated carcinogenic potential of grenz rays, is interpreted in light of the available literature on the subject. The technical bases of grenz ray therapy are also briefly reviewed.