2020-50 / December 14 

Contributor: Constantina Petraki

A man in his early 60s with a history of renal cell carcinoma metastatic to the lung presented with gastrointestinal bleeding. Endoscopy revealed multiple small polyps in the second and third segment of the duodenum, which were biopsied.


1. What is the correct diagnosis?

a. Adenocarcinoma of the duodenum

b. Metastatic clear cell renal cell carcinoma

c. Metastatic adenocarcinoma

d. Paraganglioma

e. Angiosarcoma

1. Metastatic clear cell renal cell carcinoma

Histological examination shows infiltration and ulceration of the duodenal mucosa by a neoplasm with solid, alveolar, diffuse and focally spindle cell pattern (sarcomatoid differentiation). Atypical nuclei with large nucleoli were prominent. Several mitotic figures were found. The tumor was positive for PAX8, Vimentin, CD10 and CAIX. Immunostains for CD117, CK7, CK20 and Chromogranin A were negative.

Clear renal cell carcinoma most commonly metastasizes to lung, bone, lymph nodes, liver, adrenal glands and brain. Unusual sites of metastatic spread are becoming more common. Metastasis to the gastrointestinal tract, including the small bowel as in our case, is a very rare phenomenon and an unusual cause of gastrointestinal bleeding. Clinical history, morphology and immunoprofile contribute to the correct diagnosis. The management of the gastrointestinal bleeding can be very difficult resulting sometimes in surgical intervention.

1. Peters N, Lightner C, McCaffreyJM. An unusual case of gastrointestinal bleeding in metastatic renal cell carcinoma. Case Rep Oncol 2020 ,13: 738–741.

2. Mitchell BM, Lapinski J, Rubio-Tapia A. Severe small bowel bleeding associated with metastatic clear cell renal cell carcinoma to the jejunum. Indian ACG Case REP J 2020, 7: e00397.

Constantina Petraki, MD PhD
Metropolitan Hospital, Athens, Greece

Small bowel

Clear cell renal cell carcinoma, metastasis, small bowel.