Pre-operative psoas muscle index, a surrogate for sarcopenia; as a predictor of post-esophagectomy complications

BACKGROUND: Esophagectomy is the standard of care for curative esophageal cancer. However, it is associated with significant morbidity and mortality. Esophageal cancer is known to negatively affect the nutritional status of patients and many manifest cancer sarcopenia. At present, measures of sarcopenia involve complex and often subjective measurements. We assess whether the Psoas Muscle Index (PMI); an inexpensive, simple, validated method used to diagnose sarcopenia, can be used to predict adverse outcomes in patients after curative esophagectomy.

METHODS: Multi-centre, retrospective cohort between 2010-2020, involving all consecutive patients undergoing curative esophagectomy for esophageal cancer in University Malaya Medical Centre, Sungai Buloh Hospital, and Sultanah Aminah Hospital. The cut-off value differentiating low and normal PMI is defined as 443mm2/m2 in males and 326326 mm2/m2 in females. Complications were recorded using the Clavien-Dindo Scale.

RESULTS: There was no statistical correlation between PMI and major post-esophagectomy complications (p-value: 0.495). However, complication profile was different, and patients with low PMIs had higher 30-day mortality (21.7%) when compared with patients with normal PMI (8.1%) (p-value: 0.048).

CONCLUSIONS: Although PMI did not significantly predict post-esophagectomy complications, low PMI correlates with higher 30-day mortality, reflecting a lower tolerance for complications among these patients. PMI is a useful, inexpensive tool to identify sarcopenia and aids the patient selection process. This alerts healthcare professionals to institute intensive physiotherapy and nutritional optimization prior to esophagectomy.