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.

A study on microsatellite instability status for colorectal serrated lesions / 中华内科杂志

Objective To verify the traditional serrated pathway by comparing microsatellite instability(MSI) status among traditional serrated adenoma, traditional adenoma, serrated colorectal cancer and non-serrated coloreetal cancer. Methods Seventy-five paraffin-embedded tissue samples, including 15 with serrated adeneearcinoma (Sca), 20 with non-serrated adenocareinoma (N-Sca), 20 with traditional serrated adenoma(TSA) and 20 with villous adenoma(AD) were collected from the pathology department of our hospital. Genomic DNA was extracted from these samples and then amplified with fluorescently-labeled primer specific for BAT25 and BAT26. The MSI status was detected with DNA automatic sequencer. Results Six of 18 samples with TSA harbored MSI-H and twelve MSI-L/MSS; 18 samples with conventional adenoma were exclusively of MSS; 3 of 13 samples of serrated carcinoma harbored MSI-H and ten MSI-L/MSS; 18 of 19 N-Sca samples harbored MSI-L/MSS and only one MSI-H. With Chi-square test, the MSI frequency in AD group and N-Sca group was significantly lower than that in TSA group and Sca group ( P < 0. 05 ) ; but with no statistical difference between the TSA group and Sca groups ( P > 0. 05 ). Conclusion MSI-H frequency in AD group and N-Sca group was obviously lower than that of TSA group and Sca group. It is concluded that there might be a new traditional serrated neoplasia pathway which is different from the conventional adenoma-carcinoma carcinogenesis pathway, but we still need prospective follow-up studies to verify its existence.

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.

Evaluation of the anterior transsphincteric removal of rectal villous adenoma / 中国普通外科杂志

Objective To evaluate the value and safety of the anterior transsphincteric operation for treating rectal villous adenoma.Methods The clinical data of 17 cases with rectal villous adenoma,including 6 cases with malignant change,operated by anterior transsphincteric approach at Changzheng hospital,from February 2000 to August 2006,were analyzed retrospectively.The distance between the anal verge and the lower margin of the tumor was 5～ 8 cm(average 7 cm).The tumors were 2～ 5 cm in diamater.Results The rectal villous adenoma was completely removed with negative resection margins in all the 17 patients.Fecal continence,urinary function and sexual function were preserved successfully in all the patients.No postoperative complications developed.The postoperative pathological stage of rectal villous adenoma with malignant change was pTisN0M0 in 3 cases,pT1N0M0 in 2,and pT2N0M0 in 1.At a median follow-up of 46 months,no patients had recurrence.Conclusions Anterior transsphincteric approach is useful and safe for operation of rectal villous adenomas and those with early mmalignant change.It is particularly valuable for large midrectal villous adenoma.