 the anal margin. Laboratory tests, including urinalysis, were unremarkable. Subsequent endoscopy demonstrated a narrow distal rectum, with the overlying mucosa being indurated, non-ulcerated, with a cobblestone appearance ([Fig. 1](#F1){ref-type="fig"}). Several biopsies and fine-needle aspiration were taken, but none was conclusive for diagnosis. T2-weighted MRI showed a double-layered thickening of the rectal wall with an inner iso-intense circumferential thickening of the submucosa and outer hypo-intense circumferential thickening of the muscular rectal wall, as well as a thickened bladder wall. Transrectal ultrasonography showed circumferential infiltration of the submucosa, whereas the other layers were normal ([Fig. 2](#F2){ref-type="fig"}); an image compatible with "linitis plastica". The patient underwent rectal extirpation and total cystectomy with lymph node dissection. Macroscopic examination of a sagittal section of resected rectum demonstrated an expanded submucosal layer due to infiltration with cancer cells, with intact mucosa and muscular layer ([Fig. 3](#F3){ref-type="fig"}). Histological examination of the resected bladder showed a grade III papillary transitional cell carcinoma. In the rectum clusters of tumor cells of a poorly differentiated adenocarcinoma were observed. Immunostaining was positive for both CK7 and CK20; PSA was negative. Combining the cytokeratine profile histology and transrectal ultrasonography findings, the diagnosis of a primary urinary bladder tumor with hematogenous spread to rectal submucosal layer was established.

![Endoscopic image showing circumferential narrowing of the rectal lumen, with intact overlying mucosa and cobblestone appearance](AnnGastroenterol-25-173-g001){#F1}

![Transrectal ultrasonography showing marked thickening of the rectal wall with expansion of the submucosa](AnnGastroenterol-25-173-g002){#F2}

![Macroscopic view of the resected specimen demonstrating an expanded submucosal space with intact mucosa and muscular layer](AnnGastroenterol-25-173