Multiple symmetric lipomatosis (MSL)-a rare metabolic condition characterized by diffuse, nonencapsulated, painless fat deposits-remains a challenging condition to treat. In addition, the clinical manifestation of MSL in women has not been fully understood due to the male-dominated prevalence of the disease. Here, we report a rare case of MSL with vulvar involvement and provide a review of the literature to increase the understanding of both the diagnosis and treatment of the disease. A 46-year-old Japanese woman, who had a history of chronic alcohol consumption for over 20 years, presented with bilateral giant enlargement of the labia major and complained of difficulty in walking and urination. Magnetic resonance imaging revealed nonencapsulated fat deposits involving the vulvar region and extending around the rectum. The patient underwent pubic lipectomy followed by episioperineoplasty, which resulted in a good esthetic outcome with sufficient patient satisfaction. The morphological presentation of MSL in women is different from that in men, and clinical expression of MSL in the vulvar region is rare but cannot be overlooked owing to the potential of serious sequelae such as walking difficulty, urination disorder, and sexual dysfunction. In such cases, lipectomy followed by episioperineoplasty is indicated for the treatment of the condition and its sequelae, while ensuring less chance of relapse and better esthetic outcome compared with other treatment strategies.

Background: Subcutaneous lipomas are the most common benign soft-tissue tumors. Theoretically, adipocyte sites could be the primary foci; however, lipomas are likely located in the occipital, neck, shoulder, torso, and thigh areas. To date, no study has reported the anatomical relationship between these subcutaneous structures and lipomas. Therefore, we aimed to investigate the anatomical locations of lipomas and considered their growth factors. In addition, we discussed the mechanism of fat amplification to improve the success of fat grafting. Methods: In the present study, lipomas measuring more than 5 cm in diameter from patients hospitalized between 2017 and 2021 were retrospectively examined using preoperative computed tomography and magnetic resonance imaging as well as clinical records with intraoperative pictures. Results: In total, 22 lipomas of 22 patients were examined. All lesions (100%) were accompanied by neurovascular perforators. Nineteen lesions (86%) were located deep in the superficial fascia, where it was clearly defined. Moreover, all lesions were located at the mobile adipofascial layer adjacent to an anchored fixed or less mobile structure. Conclusions: Lipoma growth might require neurovascular perforators that supply both blood flow and continuous stretching stimuli. The mobile adipofascial layer with bones adjacent to a fixed or less mobile area might also be necessary to grow lipomas. If these findings can be used as clues to elucidate the mechanism of fat amplification in the future, it may lead to an improvement in the survival rate of fat grafts.