Emphysematous epididymo-orchitis as a camouflage of prostate invasion secondary to rectum cancer

INTRODUCTION Emphysematous epididymo-orchitis is a rare cause of acute scrotum pain characterized by gas formation within the tissue. Diabetes mellitus and recto-seminal fistula secondary to sigmoid diverticulitis are generally accepted as being responsible for this disease. However, prostate invasion secondary to rectal cancer may be considered to be a newly identified pathogenetic mechanism. Herein, we report this rare case and illustrate the pathogenesis. CASE PRESENTATION A 69-year-old man arrived at our emergency department presenting with sepsis and acute scrotal pain. Emphysematous epididymo-orchitis was diagnosed by scrotal sonography initially; however, advanced rectal cancer with prostate invasion was diagnosed by CT after a recurrent episode. An exploratory laparotomy with abdominoperineal resection and radical prostectomy were performed after neoadjuvant chemoradiotherapy. Histopathologic analysis confirmed the previous diagnosis. Emphysematous epididymo-orchitis caused by advanced rectal cancer is very rare, and our case is the first to be reported according to a literature search. Neoadjuvant chemoradiotherapy plus extended surgery can achieve a good oncological outcome. CONCLUSION This case indicated that the very rare presentation as emphysematous epididymo-orchitis caused by locally advanced colorectal cancer.