The management of melanoma is directly related to Breslow's depth. Biopsying melanomas in a fashion that transects the deep margin precludes an accurate measurement of the true depth.OBJECTIVE
To examine the prognosis of melanomas transected along the deep margins, as well as cases where no residual melanoma was seen on re-excision after transection.METHODS
Records from a cohort of patients at one institution were examined from 1996 through 2007. Patients were considered to have “transected” melanomas if tumor cells were present on the deep margin of the biopsy. Overall survival was determined.RESULTS
Seven hundred fourteen patients were examined. 171 (24%) of all melanomas were transected. 101(59%) of those lacked tumor cells on re-excision. Patients with transected melanomas were older (OR = 1.03, p < .001), and had higher Breslow's depths (OR = 1.21, p < .001) than those without transected tumors. Those with no residual melanoma after transection were younger (OR = 0.98, p = .010) and more likely to have no lymph node involvement (OR = 2.23, p = .037). Neither transection (p = .760), nor lack of residual melanoma on re-excision after transection (p = .793) influenced survival.CONCLUSION
A high number of melanomas are transected at diagnosis, many of which lack visible tumor. The original Breslow's depth of transected melanomas without residual tumor on re-excision accurately predicts survival and prognosis.