Impact of combined resection of the internal iliac artery on loss of volume of the gluteus muscles after pelvic exenteration.

ABSTRACT

PURPOSE: To clarify the influence of additional internal iliac artery (IIA) resection on the loss of the gluteus muscle volume after pelvic exenteration (PE). METHODS: The subjects of this retrospective analysis were 78 patients who underwent PE with or without IIA resection (n = 44 and n = 34, respectively) between 2006 and 2018. The areas of gluteal muscles (GMs) and psoas muscles (PSMs) were calculated using CT images before and 6 months after PE, and the difference was compared. RESULTS: The volumes of the GMs and PSMs were significantly reduced after PE (P < 0.001 and P = 0.005, respectively). In the IIA resection group, the GMs were significantly reduced after surgery, but the PSMs were not. The maximum GM (Gmax) was the most atrophied among the GMs. Multivariable analysis revealed that complete IIA resection was an independent promotor of the loss of volume of the Gmax (P = 0.044). In 18 patients with unilateral IIA resection, the downsizing rate of the Gmax was significantly greater on the resected side than on the non-resected side (P = 0.008). CONCLUSIONS: The GMs and PSMs were significantly smaller after PE. Complete IIA resection reduced the Gmax area remarkably. Preservation of the superior gluteus artery is likely to help maintain Gmax size, suggesting a potential preventative measure against secondary sarcopenia.