Sarcosine in Prostate Cancer Tissue is Not a Differential Metabolite for Prostate Cancer Aggressiveness and Biochemical Progression

Purpose: Sarcosine in prostate cancer tissue samples was recently reported to be increased during prostate cancer progression to metastasis and suggested to be a key metabolite of cancer cell invasion and aggressiveness. We reevaluated sarcosine in prostate cancer tissue samples as a potential indicator of tumor aggressiveness, and as a predictor of recurrence-free survival. Materials and Methods: Sarcosine in matched samples of malignant and nonmalignant tissue from 92 patients with prostate cancer after radical prostatectomy was measured in the framework of a global metabolite profiling study of prostate cancer by gas chromatography/mass spectrometry. We related results to age, prostate volume, tumor stage, Gleason score, preoperative prostate specific antigen and biochemical recurrence, defined as a persistent prostate specific antigen increase of greater than 0.2 ng/ml. Nonparametric statistical tests, ROC curves and Kaplan-Meier analyses were done. Results: Median sarcosine content in tissue was about 7% higher in matched malignant vs nonmalignant samples, which was significantly. Sarcosine values were not associated with tumor stage (pT2 vs pT3), tumor grade (Gleason score less than 7 vs 7 or greater) or biochemical recurrence. The lack of metastatic tissue samples was a study limitation. Conclusions: Sarcosine in prostate cancer tissue samples cannot be considered a suitable predictor of tumor aggressiveness or biochemical recurrence.