Muconephrosis

Primary mucinous tumors of the renal pelvis: Clinical, histopathological, and molecular analysis of three cases

Primary mucinous tumors of the renal pelvis are extremely rare and pose challenges in terms of diagnosis and treatment. This study reviewed the clinical and pathological characteristics of mucinous tumors of the renal pelvis, including mucinous cystadenocarcinomas and mucinous cystadenomas. Immunohistochemical analysis was conducted in three cases, along with KRAS gene detection using the Amplification Refractory Mutation System (ARMS) method. The results revealed mucinous epithelium with acellular mucinous pools in all cases, and acellular mucinous pools were observed in the renal parenchyma and perirenal fat capsules. All tumors expressed CK20 and CDX2, and one case showed KRAS gene mutation. The study suggests that mucinous cystadenomas of the renal pelvis may exhibit borderline biological behaviors. This study is the first to report a KRAS gene mutation in a mucinous cystadenoma of the renal pelvis, offering valuable insights into the diagnosis and treatment of this rare condition.

Mucinous adenocarcinoma derived from villous adenoma of the kidney with muconephrosis

Upper respiratory tract villous adenoma (VA) with muconephrosis is rare and should be included in the differential diagnosis when pelvic dilatation with a solid component is detected. VA may transform into malignant mucinous adenocarcinoma, which should be suspected if contrast enhancement on computed tomography (CT)/magnetic resonance imaging (MRI) and restricted diffusion on MRI are observed.

Early diagnosis of renal pelvis villous adenoma: A case report

BACKGROUND

Villous adenoma is a rare tumor in the urinary system that usually occurs in the bladder. It is extremely uncommon in the renal pelvis. Most of the previously reported cases have been diagnosed with severe hydronephrosis associated with renal parenchyma atrophy prior to surgery. Because of its rarity, available information on the pathogenesis, diagnosis, treatment and prognosis of the disease is limited. We reported a case of kidney stones with hydronephrosis. During percutaneous nephroscopic lithotripsy, a renal pelvis tumor was found. Biopsy confirmed that the tumor was a villous adenoma of the renal pelvis.

CASE SUMMARY

A 68-year-old female was admitted to the hospital due to right kidney stones with right hydronephrosis. After admission, a urinary system plain computed tomography scan was performed, which revealed right kidney stones with right hydronephrosis and right upper ureteral dilatation. Multiple new cauliflower-like papillary masses were then discovered in the renal pelvis and calyces during right percutaneous nephroscopic lithotripsy. Biopsy results indicated villous adenoma with high-grade glandular intraepithelial neoplasia. The patient underwent laparoscopic radical resection of the right kidney and ureter. Based on histopathological and immunohistochemical examination, the patient was diagnosed with villous adenoma without adenocarcinoma.

CONCLUSION

Villous adenoma is rare in the urinary system. We reported a case of renal pelvis villous adenoma, which may provide useful information for the early diagnosis and treatment of this tumor.

Case report: A rare case of synchronous mucinous neoplasms of the renal pelvis and the appendix

Background

Mucinous neoplasms are tumors arising in the epithelial tissue, characterized by excessive mucin secretion. They mainly emerge in the digestive system and rarely in the urinary system. They also seldom develop in the renal pelvis and the appendix asynchronously or simultaneously. The concurrence of this disease in these two regions has not yet been reported. In this case report, we discuss the diagnosis and treatment of synchronous mucinous neoplasms of the right renal pelvis and the appendix. The mucinous neoplasm of the renal pelvis was preoperatively misdiagnosed as pyonephrosis caused by renal stones, and the patient underwent laparoscopic nephrectomy. Herein, we summarize our experience with this rare case in combination with related literature.

Case presentation

In this case, A 64-year-old female was admitted to our hospital with persistent pain in the right lower back for over a year. Computer tomography urography (CTU) showed that the patient was confirmed as right kidney stone with large hydronephrosis or pyonephrosis, and appendiceal mucinous neoplasm (AMN). Subsequently, the patient was transferred to the gastrointestinal surgery department. Simultaneously, electronic colonoscopy with biopsy suggested AMN. Open appendectomy plus abdominal exploration was performed after obtaining informed consent. Postoperative pathology indicated low-grade AMN (LAMN) and the incisal margin of the appendix was negative. The patient was re-admitted to the urology department, and underwent laparoscopic right nephrectomy because she was misdiagnosed with calculi and pyonephrosis of the right kidney according to the indistinctive clinical symptoms, standard examination of the gelatinous material, and imaging findings. Postoperative pathology suggested a high-grade mucinous neoplasm of the renal pelvis and mucin residing partly in the interstitium of the cyst walls. Good follow-up results were obtained for 14 months.

Conclusion

Synchronous mucinous neoplasms of the renal pelvis and the appendix are indeed uncommon and have not yet been reported. Primary renal mucinous adenocarcinoma is very rare, metastasis from other organs should be first considered, especially in patients with long-term chronic inflammation, hydronephrosis, pyonephrosis, and renal stones, otherwise, misdiagnosis and treatment delay may occur. Hence, for patients with rare diseases, strict adherence to treatment principles and close follow-up are necessary to achieve favorable outcomes.

Traditional Serrated Adenoma of the Urinary Bladder: The First Report

A 71-year-old woman was hospitalized with hematuria and underwent cystourethroscopy. Cystourethroscopy revealed a polypoid bladder tumor. Histopathologic examination showed complex villiform growth pattern, slit-like serrations, and ectopic crypts lined by epithelium with eosinophilic cytoplasm, pseudostratified elongated nuclei, consistent with traditional serrated adenoma. Nephrogenic and intestinal metaplasia with severe inflammation were present in adjacent bladder mucosa. Molecular study of the polyp revealed mutation (p.G12V) in codon 12 of exon 2 of the KRAS gene. Traditional serrated adenoma is a rare type of colonic serrated polyp, making up less than 1% of the colonic polyps with a predilection to distal colon. In the literature, there is no traditional serrated adenoma reported outside the gastrointestinal tract. Here in we report the first extra-gastrointestinal traditional serrated adenoma within the bladder and bladder diverticulum, arising from intestinal metaplasia. The present study reports an additional information on molecular background of this unusual bladder polyp.

Parenchymal mucinous cystadenoma of the kidney: a case report and literature review

Background

Mucinous cystadenoma (MC) of the kidney is exceedingly rare. We found 22 similar cases in the literature. These masses are underdiagnosed due to radiologic similarities with simple renal cysts.

Case presentation

A 66-year-old man with a previous history of hypertension and anxiety was referred to our tertiary clinic with left flank pain. Ultrasound revealed a 60 mm-sized, complex cystic mass with irregular septa in the lower pole of the left kidney (different from last year's sonographic findings of a simple benign cyst with delicate septa). CT scan showed the same results plus calcification. Due to suspected renal cell carcinoma, a radical nephrectomy was performed. Postoperative histopathologic examination revealed a cyst lined by a single layer of columnar mucin-producing cells with small foci of pseudo-stratification, consistent with the MC’s diagnosis. The first follow-up visit showed normal blood pressure without medication and no flank pain and anxiety after a month.

Conclusion

It is quite challenging to distinguish the primary MC of the kidney from a simple renal cyst based on clinical and imaging findings. The radiologic features of these entities overlap significantly. Thus, complex renal cyst and renal cysts with mural nodules should be followed closely to detect malignancy earlier.

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.

Mucinous cystadenocarcinoma in the renal pelvis: primary or secondary? Case report and literature review

INTRODUCTION

Cystic lesions in the renal pelvis may cause a diagnostic dilemma. These lesions may be benign or (pre)malignant and primary of secondary.

CASE REPORT

A 65-year-old woman presents with a complex cystic mass in the lower pole of the left kidney measuring approximately 16 cm in size and classified as Bosniak type 2F with minimally thickened septa and thick calcifications on non-contrast-enhanced computed tomography. The histopathological findings are consistent with a mucinous cystadenocarcinoma in the renal pelvis. Given the absence of a primary focus and based on clinical and radiological examination, the diagnosis of a primary renal neoplasm is preferred.

DISCUSSION

A review of the literature is performed to evaluate the histological differential diagnosis and confirm the diagnosis. Epidemiology with an overview of available similar cases since 2009, as well as etiological factors, treatment and prognosis was reviewed.

CONCLUSION

Primary renal mucinous cystadenocarcinoma is an exceedingly rare tumor. Histopathology still remains the gold standard for the diagnosis of this tumor. Because of the rarity, secondary involvement from more common sites, such as ovary and gastrointestinal tract, should be thoroughly excluded.

A rare case of huge villous adenoma of the renal pelvis deforming the abdominal wall

The villous adenoma is a benign epithelial tumor affecting most often the gastrointestinal tract, especially the colon and rectum. The incidence of this disease in the genitourinary tract is less than 1% as the most commonly affected organs are bladder, urethra, prostate, vulva and vagina. Only several cases of villous adenoma in the renal pelvis have been reported in the scientific literature. The disease is more common in men between the ages of 40 and 70. We presented a rare case of huge villous adenoma of the renal pelvis in 61 years old man.

Primary mucinous adenocarcinoma of the renal pelvis misdiagnosed as calculous pyonephrosis: a case report and literature review

Primary mucinous adenocarcinoma of the renal pelvis is a rare malignant disease that is difficult to diagnose preoperatively. There are still no characteristic symptoms, radiological features, or standard treatment for this tumor with only ~100 cases reported. The prognosis is poor. We report a case of a 66-year-old man who presented with a 2-month history of fever and right waist pain. He was misdiagnosed with calculous pyonephrosis and underwent percutaneous nephrostomy (PCN) at a local hospital. Gelatinous material was drained via a PCN catheter. He was then transferred to our hospital. He had elevated CEA and CA19-9. We performed an open radical nephrectomy and found polypoid, gelatinous material and stones filling the renal pelvis. He was diagnosed with primary mucinous adenocarcinoma of the renal pelvis by pathology. He refused adjuvant chemotherapy and there was no sign of recurrence after one year of follow-up. By assessing a literature review of all of the cases reported since 2000, we recommend that careful history taking, serum tumor markers, and CT scans may improve the diagnostic accuracy rates and radical nephrectomy with total ureterectomy accompanied by adjuvant therapy may improve the prognosis.

Villous Adenoma in Renal Pelvis With Manifestation of Percutaneous Fistula and Mucus Secretion

A 70-year-old man, complaining of percutaneous fistula with jelly-like yellow mucus in the right kidney for a month, was admitted to our department. From computed tomography, stones and severe hydronephrosis but no suspicious mass was found in right kidney. Nephrectomy of right kidney was performed and pathological examination revealed a villous adenoma in the renal pelvis with moderate to severe atypical hyperplasia of glandular epithelium. Primary villous adenoma in renal pelvis is rare and believed to be related to chronic irritation of stone and inflammation. Mostly nephrectomy was performed before diagnosis was made.

Mucinous cystadenoma of a horseshoe kidney: A case report and literature review

A 45-year-old man complained of a palpable mass in his left abdomen. Computed tomography showed a horseshoe kidney with a Bosniak type II complicated cyst from a left segment. Three years after his initial examination, due to the growing cystic lesion and the compression imposed on the urinary collecting system and surrounding organs, we performed a left heminephrectomy. The diagnosis was mucinous cystadenoma of the kidney. No recurrence was observed 6 months after surgery. The histopathology was unique since the inner surface of the cyst was covered by a mucin-positive columnar epithelium connected to a urothelium, with continuous transition between the two. This suggests that the mucinous tumour may have originated from a sequestered segment of the renal pelvic epithelium in the renal parenchyma.

Intestinal metaplasia of the renal pelvis: A case report and literature review

Metaplastic changes in the renal pelvis are infrequent and may be malignant transformations to adenocarcinoma. The current study reports a case of intestinal metaplasia in the right renal pelvis, which was associated with staghorn calculi, in a 56-year-old female. The patient underwent a percutaneous nephrolithotomy. Immunohistochemical assessment of the mucosa of the renal pelvis revealed the positive expression of carcinoembryonic antigen, cytokeratin (CK)-7 and CK20, but negative expression for CK5/6 and vimentin. Furthermore, Ki67 expression was diffusely positive, while p53 was negative. Unlike other previously reported cases, the patient opted for active surveillance as opposed to radical nephrectomy, following the removal of the calculi. No evidence of progression was observed after three years of follow-up. Therefore, etiological treatment and close follow-up may be a suitable treatment option for localized intestinal metaplasia.

Mucinous cystadenoma of the pyelocaliceal system: a report of 3 examples and an analysis of 17 previously published cases

We report 3 patients all men between 45 and 64 years of age with unilocular or multilocular mucinous cystadenomas of the kidney. One tumor arose from the renal pelvis, and 2 involved the entire pyelocaliceal system. The tumors measured between 2.4 and 37 cm in greatest dimension. Two patients were asymptomatic, and 1 had recurrent attack of acute pyelonephritis. Microscopically, the morphology and immunophenotype (CK20, MUC2, and CDX2 positive) of the tumors were similar to the colonic adenomas. Two patients were asymptomatic 24 and 64 months after surgery, including the patient with mucinous cystadenoma and intramucosal carcinoma. One patient died of acute myocardial infarction, and his tumor was an autopsy finding. Only 17 cases of mucinous cystadenomas and 5 cases of mucinous cystadenocarcinomas have been reported. Of the 17 mucinous cystadenomas, 2 arose in horseshoe kidneys. The mean size of these neoplasms was 15 cm (2.4-37 cm). Despite their large size, some patients with mucinous cystadenomas were asymptomatic. Sixty percent were associated with renal lithiasis. Thirty percent progressed to mucinous adenocarcinomas, and only 2 cases showed areas of intramucosal carcinomas. Two cases were associated with carcinoid tumors, similar to those reported in the appendix. Most patients were asymptomatic after surgery, and only 1 patient died by abdominal sepsis related to adenomucinosis. The 3 examples of mucinous cystadenomas of the pyelocaliceal system reported here, and those previously published indicate that they are very uncommon neoplasms with morphology and intestinal immunophenotype similar to the colonic adenomas.

Intestinal type villous adenoma of the renal pelvis

Intestinal type villous adenomas are uncommon in the genitourinary tract. Most reported cases have been located in the urinary bladder or urachus. Villous adenoma arising in the renal pelvis or ureter is very rare. We present a case of an 81-year-old female who presented with difficulty voiding and mucosuria. A computed tomography scan identified right-sided hydronephrosis, renal parenchymal atrophy, nonobstructing calculi and a lower pole renal mass. She underwent open right nephrectomy. Histopathologic examination of the kidney revealed an intestinal type villous adenoma of the renal pelvis with high-grade dysplasia and focal areas suspicious for invasive adenocarcinoma. We review the four previously reported cases of intestinal type villous adenoma in the renal pelvis and discuss diagnosis and management of this unusual neoplasm.

Renal pelvic villous adenoma presented with mucusuria: report of a case and literature review

Villous adenomas of the urinary tract are an uncommon condition, and appear mostly in patients where the disease occurred in the lower urinary tract. In contrast, upper urinary tract villous adenomas are a rare condition. Currently, just three cases of villous adenoma in the renal pelvis have been published. Herein, we present the fourth case of a renal pelvic villous adenoma, along with muconephrosis and mucusuria. A 73-year-old man presented with abdominal discomfort and a palpable abdominal mass. He had a history of bilateral anatrophic nephrolithotomy, 8 years and 6 years earlier. The preoperative radiographic investigation showed severe right hydronephrosis. A right nephrectomy was carried out and the intraoperative finding showed severe perinephric adhesion and a great deal of mucus in the renal pelvis. The pathological examination showed a villous adenoma and urothelial metaplasia in the kidney.

Primary mucinous adenocarcinoma of the renal pelvis with elevated CEA and CA19-9

Primary adenocarcinoma of the renal pelvis is rarely reported in the literature. Here we present a case of primary mucinous adenocarcinoma of the renal pelvis with elevated serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels. A 56-year-old woman was referred to our center with intermittent fever and left-sided back pain for 1 month. Computed tomography showed bilateral nephrolithiasis, mild right hydronephrosis and left pyonephrosis accompanied with ambiguous soft tissues. A radionucleorenogram showed that the glomerular filtration rate of the left and right kidney was 0 and 79 ml/min, respectively. Left nephrectomy was performed without lymph node dissection. Histopathology revealed mucinous adenocarcinoma and elevated serum CEA and CA19-9 levels were found. She died of multiorgan metastasis after 5 months. A review of the literature is also reported.

Villous adenoma of the renal pelvis and ureter

Villous adenoma originating in the urinary tract is a rare condition. Mucus-filled kidney (muconephrosis), one of the manifestations of this condition, occurs due to intestinal type of metaplastic changes occurring in the urothelium. This condition is commonly associated with urolithiasis and/or chronic infection. Concomitant adenocarcinomatous changes in the urothelium may be present along with this and unless a careful search is made to identify this, this serious condition may be overlooked leading to an inappropriate follow-up and dire consequences. We are reporting the third case of muconephrosis due to villous adenomatous changes of the renal pelvis and ureter.

Primary mucinous cystadenocarcinoma of renal pelvis: a case report

Background

We report a case of primary mucinous cystadenocarcinoma of renal pelvis which radiologically resembled large multicystic mass in 45 years old man.

Case Presentation

The patient referred to our center with loin pain and progressive abdominal distention from 4 years ago. In the previous published literature, four cases of mucinous cystadenocarcinoma of renal origin have been published. Abdominal CT showed complete replacement of left kidney by a large multiloculated cystic mass accompanied with multiple large nephrolithiasis. Nephrectomy was performed and histopathology revealed covering of epithelium of renal pelvis by columnar epithelium and scattered goblet cells and mucous gland.

Conclusion

Mucinous cystic neoplasms of kidney are rare entity and our case and few similar reported cases showed that this tumor is an unique clinicopathologic renal mass that may be classified by World Health Organization classification in the future

Pseudomyxoma peritonei associated with primary mucinous borderline tumor of the renal pelvicalyceal system

Primary mucinous cystic neoplasms are extraordinarily rare tumors of the kidney. Herein, we present a case of a 52-year-old man who presented with painless hematuria and mucusuria. The nephrectomy showed a markedly enlarged kidney replaced by a large cystic mass filled with mucin and with almost complete destruction of the renal parenchyma. Histologically, the mass was lined primarily by simple mucinous epithelium and showed foci of adenomatous (borderline) change with focal areas exhibiting intraepithelial carcinoma. No invasion was documented after extensive sampling of the tumor. A pathologic diagnosis of intraepithelial carcinoma arising in a mucinous neoplasm of borderline malignancy was rendered. One year later, the patient presented with pseudomyxoma peritonei. This case illustrates that, in a patient with pseudomyxoma peritonei, the absence of an appendiceal, gastrointestinal, or ovarian primary tumor raises the possibility of a primary neoplasm at an unusual site such as the kidney.

Villous adenoma of the ureter with manifestation of mucus hydroureteronephrosis

Ureteral tumor is prone to result in lumen obstruction. Villous adenoma is most frequently found in the colon and rectum, seldom in the urinary tract and even more rarely in the ureter or pelvis. Herein, we present a case of bilateral renal stones of more than 10 years' duration with the chief complaint of right flank pain. Obstruction of the right upper ureter with hydroureteronephrosis was observed on sonography, computed tomography and retrograde pyelography. Ureteroscopy revealed papillary tumor obstructing the upper third of the ureter and inducing hydroureteronephrosis with abundant mucoid content. The ureteral tumor proved to be villous adenoma by pathologic examination. It should be noted that ureteral villous adenoma may be related to previous enteric-type metaplastic mucosa or ureteritis glandularis, demonstrates profuse production of mucus, and may eventually undergo malignant transformation.

[Villous adenoma of the renal pelvis and ureter]

Villous adenomas of the urinary tract are extremely rare tumours belonging to the adenoepithelial metaplasias. They can be associated with other neoplasias, especially with carcinomas. We describe the case of an 85-year-old female patient suffering from a villous adenoma of the renal pelvis and ureter.