Clinical complete response maintained for more than 5 years after aggressive chemoradiotherapy for advanced rectal cancer with necrotizing fasciitis: a case report.

We report the case of a 65-year-old male diagnosed with advanced rectal cancer associated with necrotizing fasciitis (NF). Since radical surgery, total pelvic exenteration with sacrectomy, was rejected because of detrimental effects on quality of life, chemoradiotherapy (CRT) was chosen as anti-cancer treatment after urgent debridement. Although CRT was paused unintentionally just after delivering the total dose of radiation owing to the relapse of NF, the patient has maintained clinical complete response (cCR) without any distant metastasis for >5 years. Advanced rectal cancer is recognized as an NF risk factor. No definitive treatment strategies have been reported for NF-inducing rectal cancer; however, some reports have demonstrated curative extended surgery. Thus, CRT may be a less-invasive treatment option for NF-inducing rectal cancer, whereas severe adverse effects including re-infection after debridement should be closely monitored.