In Reply.—The purpose of our short article was not to stir any controversy. The questions raised by Wolinsky and Silvers are well taken. We are aware of the pitfalls and drawbacks of retrospective studies.
Our report was based on a study of all thin melanomas that were less than 0.76 mm in maximal thickness over a period of 25 years. Most of the patients were followed up for long periods, with a median follow-up of 76 months and an average follow-up of 102 months. Twenty-one of these patients were studied retrospectively and only 15 patients were studied prospectively. All primary melanomas prospectively studied were step sectioned and only 13 of 21 melanomas retrospectively studied were step sectioned. In eight patients the paraffin blocks were unavailable and we had to depend on two or three sections stained with hematoxylin-eosin for this review. It would be presumptuous to say that these