2622 A Case of Metastatic Renal Cell Carcinoma to the Jejunum Presenting as Iron Deficiency Anemia

Abstract

INTRODUCTION: Small bowel malignancies comprise only 0.35% of all malignancies and small bowel metastases only comprise 2% of malignancies, only 7.1% of which are from a primary renal cell carcinoma (RCC).This case demonstrates a rare metastatic RCC of the small bowel diagnosed through video capsule endoscopy (VCE) prompting an antegrade double-balloon enteroscopy (DBE). CASE DESCRIPTION/METHODS: A 53-year old male with hypertension, diabetes mellitus, and anemia presented with a rapidly worsening, necrotic right lower quadrant abdominal wall lesion. Dermatopathology from a wound edge biopsy demonstrated an ulcer with neutrophils and karyorrhectic debris, consistent with pyoderma gangrenosum (PG). He was found to have iron deficiency anemia (IDA) requiring multiple blood transfusions and iron infusions. Colonoscopy and esophagogastroduodenoscopy were unremarkable. VCE demonstrated markedly abnormal mucosa in the proximal jejunum, occupying at least 75% of the lumen with several satellite lesions. Antegrade DBE revealed a large ulcerated jejunal mass with leakage of serosanguinous fluid. Pathology showed poorly-differentiated carcinoma of unknown etiology. Pan-CT revealed a 5.6 × 5.4 cm solid mass in the right kidney with invasion of the right renal vein with thrombus extending into the inferior vena cava, liver masses, and pulmonary nodules consistent with metastatic renal cell carcinoma. DISCUSSION: This is a rare case of RCC metastatic to the small bowel. Only three other case studies report this in the literature. Approximately 25–30% of patients have metastatic disease at time of RCC diagnosis. The most common sites of metastasis for RCC include lymph nodes, lung, bone, liver and brain. Metastasis to the small bowel often originate from cancers of the breast, lung, esophagus, head and neck, and melanoma. While there have been case reports of jejunal metastases many years status-post nephrectomy, there have only been three reported cases of synchronous jejunal metastases from RCC. Metastatic RCC to the small bowel can present as gastrointestinal bleeding and intussusception. VCE and DBE were useful diagnostic tools in our particular case. CT or MR enterography may have also served as an appropriate diagnostic alternative, and in retrospect may have helped to make the diagnosis sooner. Overall, it is important to consider small bowel malignancy on the differential diagnosis in a patient who presents with IDA.