Low Serum Alanine Aminotransferase Blood Activity Is Associated with Shortened Survival of Renal Cell Cancer Patients and Survivors: Retrospective Analysis of 1830 Patients

<b>Background:</b> Sarcopenia is characterized by a loss of muscle mass and function and is often associated with frailty, a syndrome linked to physical disability and shortened survival in various patient populations, including cancer patients. Low serum alanine aminotransferase (ALT) values, serving as a biomarker for sarcopenia, were previously associated with frailty and shortened survival in several cancers. In the current study, we aimed to test the association between low ALT and shorter survival in renal cell carcinoma (RCC) patients and survivors. <b>Methods:</b> This was a retrospective analysis of RCC patients and survivors, both in- and outpatients. We defined patients with sarcopenia as those presenting with ALT < 17 IU/L. <b>Results:</b> We identified records of 3012 RCC patients. The cohort included 1830 patients (mean age 65.6 ± 13.3 years, 68% were men) of whom only 179 underwent surgical treatment. Out of the eligible cohort, 811 patients (44.3%) had ALT < 17 IU/L, with a mean ALT value of patients within the low-ALT group of 11.79 IU/L, while the mean value in the higher ALT level group was 24.44 IU/L (<i>p</i> < 0.001). Patients in the low-ALT group were older (67.9 vs. 63.7 years; <i>p</i> < 0.001) and had lower BMIs (26.6 vs. 28; <i>p</i> < 0.001). In addition, patients with low ALT had lower hemoglobin values (12.14 vs. 12.91 g/dL; <i>p</i> < 0.001), higher serum creatinine (1.49 vs. 1.14; <i>p</i> < 0.001) and higher platelet to lymphocyte ratios (178 vs. 156; <i>p</i> < 0.001). In a univariate analysis, low ALT levels were associated with a 72% increase in mortality (95% CI 1.46-2.02, <i>p</i> < 0.001). In a multivariate model controlled for age, gender, hemoglobin, platelets, LDH, neutrophil to lymphocyte ratios and platelet to lymphocyte ratios, low ALT levels were still associated with a 27% increase in mortality (HR = 1.27, 95% CI 1.08-1.51; <i>p</i> = 0.005). <b>Conclusion.</b> Low ALT values, associated with sarcopenia and frailty, are also associated with shortened survival in RCC patients, and survivors and could potentially be applied for optimizing individual treatment decisions.