Villous adenoma of the renal pelvis: a common entity at an uncommon location.

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Villous adenoma of the renal pelvis: a common entity at an uncommon location

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Síndrome de McKittrick-Wheelock: una causa infrecuente de hipokalemia e injuria renal aguda. Caso clínico / McKrittick-Wheelock syndrome: report of one case

McKittrick-Wheelock syndrome is caused by chronic water and electrolyte hypersecretion from an intestinal tumor, usually a villous adenoma, located in the rectum or sigmoid. Patients often have dehydration, hypovolemic shock and kidney failure associated with hypokalemia, hyponatremia, hypochloremia and metabolic acidosis. We report a 62-year-old male, suffering chronic diarrhea for eight years who was admitted after a syncope. He had severe hypokalemia, hyponatremia, metabolic acidosis, hypovolemia and acute renal failure. After his metabolic disorders were corrected, a colonoscopy showed a large rectosigmoid tumor with the characteristics of a villous adenoma. During the follow up after the complete tumor resection, the patient has remained asymptomatic.

Síndrome de McKittrick-Wheelock: una causa infrecuente de shock hipovolémico / McKittrick- Wheelock syndrome: report of one case

Villous colorectal adenomas are common tumors that normally provoke scarce symptomatology. We report a 59 year-old female that was admitted with severe dehydration due to severe diarrhea lasting 10 days and vomiting in the last 48 hours. On rectal palpation a large tumor located 5 cm above the anus was palpated. Colonoscopy confirmed the presence of a villous adenoma that was excised surgically. In this patient, the fluid and electrolyte hypersecretion of the rectal villous adenoma provoked a depletion syndrome with serious hydroelectrolytic alterations, acute renal failure and hypovolemic shock. This syndrome was first described by McKittrick and Wheelock in 1954.