Superior Mesenteric Venous Thrombosis: Paraneoplastic Manifestation of a Rare Renal Cell Carcinoma

Abstract

Mesenteric venous thrombosis is a rare but lethal form of mesenteric ischemia and it is a well-established cause of intestinal ischemia. Malignancy is recognized as an important risk factor. Multilocular cystic renal cell carcinoma (MCRCC) is a rare cystic tumor of the kidney with a good prognosis and in most of the cases the diagnosis is made incidentally. A 69-year-old man with a past medical history of arterial hypertension, dyslipidemia and coronary artery bypass surgery, presented in the emergency department with colic abdominal pain. His abdominal examination was notable for tenderness in the right iliac fossa on palpation and laboratory work-up revealed leukocytosis 13x109 U/L and elevated C-reactive Protein (33 mg/L). Contrast-enhanced computed tomography (CT) showed hypoenhancing wall thickening of the distal ileum (50 cm) and a filling defect within the superior mesenteric vein, consistent with ischemia of a large segment of the ileum (Figure 1). Small bowel resection of 70 cm of ileum was performed with primary anastomosis (Figure 2). The prothrombotic study did not reveal Protein C, Protein S and antithrombin III deficiency or factor V Leiden mutation. Myeloproliferative disorders were also excluded. Six months later, a contrast enhanced CT showed in the middle part of the right kidney a heterogeneously enhancing, well-defined, mass lesion with 33 mm (Figure 3). This lesion was previously described in the first CT scan and maintained the same dimensions. Nonetheless, since cystic renal cell carcinoma could not be excluded, a right-sided nephrectomy was performed. The gross examination of the kidney revealed a cystic lesion of 2.8 × 1.5 cm dimension containing mucinous material. Histopathological examination revealed a MCRCC staged as pT1a Nx R0.Figure 1Figure 2Figure 3Herein we describe a patient with mesenteric venous thrombosis without inherited prothrombotic conditions, abdominal surgeries or traumatic injuries. Additional investigation showed that the probable cause for the thrombotic event was a rare renal cell cancer (MCRCC). To the best of our knowledge, this is the first case described in the literature of small intestinal ischemia secondary to superior mesenteric vein thrombosis associated with a MCRCC. In fact, cancer is recognized as an important condition that predisposes patients to a hypercoagulable state and therefore a risk factor for trombothic events. This case highlights the importance of identifying the underlying pathology which leads to thrombosis as it conditionates the long-term management and well-being of these patients