Core Muscle Size Predicts 6-Month Mortality in Patients Undergoing Radical Cystectomy

Posted on June 2014

Resident Hailey Allen, M.D., presented a lecture detailing the use of core muscle size measurements as a quantitative predictor of 6-month mortality in elderly patients undergoing radical cystectomy.

The process of determining surgical candidacy is complex and considers many elements. One such factor is patient frailty, but the line between being fit for surgery or being too frail to undergo the procedure is fuzzy and undefined. The need for a quantitative measurement is apparent, and that measurement can be determined through imaged-based measurement of core muscle size.

While this study focused on patients afflicted with urothelial carcinoma, previous studies have included populations suffering from HCC, pancreatic cancer, and colon cancer. Many of those studies found significant correlation between the muscle size measurements and patient mortality, complication rate and severity, length of stay, and even cost of treatment.

The cross-sectional area and density of the psoas muscles surrounding the L4 vertebra were measured using CT in 128 patients. The correlation between survival and total psoas area (TPA) was found to be statistically significant, as patients with a high TPA consistently lived longer post-surgery than their low-TPA peers.

However, the study was faced with limitations, including a small sample size, and lack of statistical significance connecting TPA to length of stay or complication rate. In the future, Allen would like to use a sample size large enough for subgroup analysis, to further refine the results.