Colonic pneumatosis and intestinal perforations with sunitinib treatment for renal cell carcinoma.

Keywords Pneumatosis.Intestinalperforations.Sunitinibtreatment.RenalcellcarcinomaCase historiesPatient 1 A woman with renal cell carcinoma (RCC)presented with sudden right sided flank pain and anuria.Two years earlier she was diagnosed with RCC clear celltype and had a left-sided nephrectomy performed at thattime. Her initial staging evaluation revealed multiplepulmonary nodules consistent with metastatic disease andshe was started on sorafenib therapy. She remained on thistherapy for 9 months, but was then found to haveprogressive disease and high-dose interleukin-2 (IL2) wasinitiated. The patient developed bilateral pulmonary edemaduring her initial course of IL2 which was believed to besecondary to IL2-induced capillary leak and requiredendotracheal intubation. Accordingly, IL2 was abandonedwithout completing a full course and treatment withsunitinib (50 mg daily for 4 weeks followed by a 2 weekbreak) was pursued.Thirteen months after starting sunitinib, the patientdescribed approximately 12 h of acute right-sided flankpain with no urine output over that time period. Her pasthistory included a tiny calculus in the right kidney. Shedenied vomiting, diarrhea or recent change in her bowelmovements. Laboratory analysis revealed a lactate of3.5 mmol/l (normal range 0.5–2.2 mmol/l). A computedtomography (CT) exam of the abdomen and pelvis wasordered, showing colonic pneumatosis on the right andpneumoretroperitoneum (Fig. 1a–d). The patient proceededto surgery, with placement of a ureteral stent and a right-sided hemi-colectomy. Cystoscopy and an intraoperativeretrograde ureteropyelogram did not demonstrate an ob-structive stone and the anuria was attributed to gastrointes-tinal perforation (GIP). Pathologic examination of the rightcolon showed extensive pneumatosis cystoides intestinalis(Fig. 1e) and focal areas of ulceration of the mucosa withtransmural acute and chronic inflammation and giant cellreaction (Fig. 1f); microthrombi were observed in thevessels of the lamina propria. Three regional lymph nodes