Surgical management of lipomas: Proposal of the Z-incision design and surgical algorithm based on tumor size.

Abstract

Surgical excision is the treatment of choice for lipomas. However, linear incision methods or minimal extraction techniques often do not provide a sufficient surgical view. Therefore, removing large lipomas is often difficult. To present the Z-incision and half Z-incision designs for lipoma extraction, this retrospective study analyzed lipomas surgically excised at our institution between September 2015 and December 2018. The area of surgical field exposed by the Z-incision versus that exposed by the linear incision was calculated using a schematic model. Cure rate, complications, and surgical field area were investigated. A total of 84 lipomas were included. A Z- or half Z-incision was used to treat 30 lipomas, while a linear incision was used to treat 54 lipomas. The mean diameter of the mass in the Z- or half Z-incision group was 47.7 mm (range, 15-160 mm), larger than that in the linear incision group (25.5 mm; range, 7-59 mm) (p < .001). The Z-incision involved making rectangular windows by lifting 2 triangular flaps. According to our mathematical model, the Z-incision provided a larger surgical field area than that provided by the linear incision based on stretched angles (1.81 times larger at 30° and 3.14 times larger at 15°). The Z- and half Z-incisions were successfully performed in all but 1 lipoma (29 lipomas, 96.7%). There was 1 lipoma that resulted in postoperative complications (seroma, 3.3%). The Z-incision design can be a useful alternative technique for the extirpation of lipomas, especially large lipomas. Here, we proposed a surgical algorithm for lipoma surgery based on tumor size.