Untreated for 20 Years: A 14 Kilogram Subcutaneous Lipoma

Abstract

Lipomas are the most common benign mesenchymal tumors found in humans, with a prevalance rate of 2.1 per 1000 tumors. Most of them are small, weighing only a few grams and measuring less than 2 centimeters in diameter. However, those weighing upwards of 200 grams and exceeding 10 centimeters have only been described in different anatomic locations on occasion in the literature. A 54-year-old man presented with a large soft tissue growth over the lower back, present for the past 20 years and rapidly enlarging over the past 3 years. A diagnosis of giant lipoma was made. Six hours and several surgical teams were required to remove the 14 kilogram mass. During excision, the skin flaps overlying the mass were preserved and were ultimately used to reconstruct the surgical site defect in a layered fashion once intraoperative frozen pathology confirmed the pre-operative diagnosis. Benign lipomas of the size reported in this case have rarely been described in the literature, as lipomatous masses of this size are often found to instead be either atypical lipomatous tumors or high-grade liposarcomas. In this case, we describe one of the largest of these giant benign lipomas ever reported to date. The case also illustrates the use of an interdisciplanary, multi-team approach to undertake the high-risk operation of removing such a mass from a patient safely. Finally, the case describes aninteresting approach toward reconstructing the large soft tissue defect that remained once the tumor had been removed from the patient.