Cutaneous melanoma: preoperative tumor diameter in a general dermatology outpatient setting

Abstract

Background: The ABCD mnemonic for cutaneous melanoma indicates that tumor diameter (D) is typically greater than 6 mm.

Objective: To determine the distribution of preoperative tumor diameter in a midwestern United States general dermatology practice-based case series.

Methods: Patient records were reviewed for preoperative maximal tumor diameter for primary cutaneous melanomas diagnosed between January 1, 2006, and February 1, 2012.

Results: Of 116 tumors for which preoperative measures were available, 38 (32.8%) had a diameter of 6 mm or less. Of these 38 small-diameter (≤6 mm) cases, tumor invasion occurred in 26 (68.4%), compared with 36 of the 78 (46.2%) larger-diameter (>6 mm) cases. Small-diameter tumors were significantly more common in patients younger than 60 and almost twice as common in women than men.

Conclusions: Almost one-third of evaluable tumors in this general dermatology practice-based setting had a preoperative diameter of 6 mm or less, and two-thirds of these small-diameter cases were invasive. The diameter criterion of greater than 6 mm in the ABCD mnemonic is precariously insensitive for a public message.