Absence of bladder cancer cells in surgical smoke from robot-assisted radical cystectomy: a prospective study

After robot-assisted radical cystectomy (RARC) for bladder cancer, urologists occasionally encounter distinct recurrences, including port site recurrence and peritoneal dissemination. We hypothesize that the surgical smoke generated during RARC could contain bladder cancer cells, potentially leading to dissemination. Initially, we examined the cytology of the exhaust smoke filters used during laparoscopic radical cystectomy; however, no cancer cells were detected. Subsequently, we conducted digital PCR analysis for the PIK3CA (E545K) gene mutation in surgical smoke collected through a water trap system during RARC. However, we were unable to detect any mutated genes. We subjected T24 bladder cancer cell line pellets to electrocoagulation vaporization and subsequently captured the surgical smoke through a vacuum system. However, we could not detect the TERT (C228T) mutation in the smoke. Consequently, we proceeded with exosome analysis of the smoke obtained from electrocoagulated pellets and the supernatant of T24 cells as the control. The exosome levels in smoke were significantly lower than that in controls. Based on these findings, we concluded that the surgical smoke produced during RARC does not contain cancer cells, genes, or exosomes.