Depth of melanoma invasion is critical because it dictates patient treatment and prognosis. Recent reports indicate melanoma transection with initial biopsy does not impact patient survival; however, tumor transection can lead to misdiagnosis and inaccurate staging.

This study assessed the rate of melanoma transection with various biopsy techniques and the impact of tumor transection on patient survival.

We conducted a retrospective review of all melanoma cases at our institution between 2000 and 2008. Of the 490 melanoma cases identified, 479 met inclusion criteria for the study. The transection rates of biopsy techniques were determined. Cases of transected tumors were matched with nontransected cases in a retrospective case-control fashion to evaluate survival.

The rate of melanoma transection was 1.5% for excisional biopsies, 4.1% for punch biopsies, and 9.0% for saucerization biopsies. The means of disease-free survival for the control and transected groups were 911 days and 832.7 days, respectively (P value .67). Overall survival for the control group was 1073.7 days versus 1012.4 days for the transected group (P value .72).

The study used a select population. The sample size of transected biopsies was limited, in turn limiting the power of the study. Residents performed the majority of biopsies.

Punch and saucerization biopsies were more likely to transect tumors than excisional biopsies. The transection of melanoma did not affect overall disease-free survival or mortality in the population studied.