Kim WT, Kang HW, Seo SP, et al. - This study was undertaken to investigate the effect of the pre-operative internal obturator muscle (IOM) mass index on biochemical recurrence (BCR) of prostate cancer (PCa) patients who had undergone radical prostatectomy. Researchers recruited a total of 222 patients, who had undergone open, laparoscopic, or robot-assisted radical prostatectomy at seven centers in 2011 and were followed up for 5 years. They analyzed BCR in the context of pre-operative IOM mass index and BMI. It was shown that pre-operative IOM mass index was not correlated with BCR; nevertheless, long-term follow-up is necessary to assess cancer-specific and overall survival of PCa patients.