Implantation of Colorectal Cancer from the Upper Urinary Tract to the Bladder via Urine

Abstract

Although the implantation of urothelial carcinoma from the upper urinary tract to the bladder occurs frequently, the involvement of cancers of other histologic types is rare. Here, we present an unusual case of intravesical recurrence, following ureteral invasion, by colorectal cancer. A 69-year-old woman developed a local recurrence of colorectal cancer involving the sigmoid colon and left ureter. The patient underwent a sigmoidectomy and left nephroureterectomy. Six months later, bladder tumors were observed, and a transurethral resection was performed. Histological examination of the bladder tumors revealed adenocarcinoma consistent with the findings of the colorectal cancer that had been previously resected. The most probable mechanism of intravesical recurrence would be the implantation of colorectal cancer cells from the upper urinary tract to the bladder via urine.