Saudi Journal of Kidney Diseases and Transplantation

CASE REPORT
Year
: 2014  |  Volume : 25  |  Issue : 3  |  Page : 647--650

Mucinous cystadenocarcinoma of renal pelvis presenting as pyonephrosis


Rashmi D Patel1, Aruna V Vanikar1, Pranjal R Modi2,  
1 Department of Pathology, Laboratory Medicine and Transfusion Services and Immunohematology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Center-Dr. H. L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India
2 Department of Urology and Transplantation, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Center-Dr. H. L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad, Gujarat, India

Correspondence Address:
Dr. Rashmi D Patel
Department of Pathology, Laboratory Medicine and Transfusion Services and Immunohematology, G. R. Doshi and K. M. Mehta Institute of Kidney Diseases and Research Centre-Dr. H.L. Trivedi Institute of Transplantation Sciences, Civil Hospital Campus, Asarwa, Ahmedabad 380016, Gujarat
India

Abstract

Mucinous cystadenocarcinoma of renal pelvis is a rare epithelial tumor with poor prognosis. It is postulated to arise from metaplastic glandular mucosa in response to chronic irritation, and comprises less than 0.3% of total renal pelvic tumors. We present this case of a tumor noted in a 45-year-old lady that was diagnosed as mucinous cystadenocarcinoma on histological examination after radical nephrectomy. The patient is remaining well over a follow-up of three months.



How to cite this article:
Patel RD, Vanikar AV, Modi PR. Mucinous cystadenocarcinoma of renal pelvis presenting as pyonephrosis.Saudi J Kidney Dis Transpl 2014;25:647-650


How to cite this URL:
Patel RD, Vanikar AV, Modi PR. Mucinous cystadenocarcinoma of renal pelvis presenting as pyonephrosis. Saudi J Kidney Dis Transpl [serial online] 2014 [cited 2020 Jul 13 ];25:647-650
Available from: http://www.sjkdt.org/text.asp?2014/25/3/647/132224


Full Text

 Introduction



Majority of the malignant renal pelvic tumors are epithelial in origin. The tumor is associated with long-standing obstruction and infection, possibly originating from the metaplastic epithelium. [1] We report this case of an unusual tumor, mucinous cystadenocarcinoma, encountered in association with nephrolithiasis and pyonephrosis, diagnosed only after histopathology examination.

 Case Report



A 45-year-old lady presented with low-grade fever and right flank pain of two months duration. On investigations, her hemoglobin was 12.7 g/dL, total WBC count was 6.5 × 10 3 / μL, serum creatinine (SCr) was 0.88 mg%, electrolytes were in the normal range and random blood sugar was 86 mg/dL. Urine albumin was in faint traces, microscopy revealed 60-65 pus cells/high-power field (HPF) and 8-10 RBCs/HPF with a few calcium oxalate crystals. Culture revealed Pseudomonas aeruginosa, 1 million colonies, sensitive to levofloxacin. Ultrasonography (USG) revealed pyonephrotic right kidney (RK), 17.2 × 8.4 cm with giant hydronephrosis, paper-thin parenchyma with debris, internal echoes ++ and 9 × 3 mm-sized calculus in the lower calyx. The left kidney was 12.5 × 4.5 cm, and otherwise unremarkable. The urinary bladder was normal. Percutaneous nephrostomy (PCN) was carried out and 300 mL pus mixed with jelly-like material was aspirated, microscopy revealed it to be loaded with pus cells, levofloxacin-sensitive E. coli were isolated and treated. Follow-up after one week showed unremarkable laboratory parameters, except persistence of 120-140 pus cells/HPF in urine, no organisms were isolated. Three weeks later, the PCN output had stopped and intravenous pyelography was performed, which showed no urine excretion from the right kidney for 24 h. A 10-mm-sized stone was observed in the lower calyx. The left kidney had prompt excretion. Again a PCN diversion was performed and 500 mL pus and jelly-like material mixed urine was aspirated, three days later, PCN was once again blocked. A computed tomography (CT) scan was performed, which revealed RK enlarged, pyonephrotic with calcified shadows, suggestive of chronic changes associated with calculi in the lower calyx. The left kidney was unremarkable [Figure 1]. It was decided to surgically remove the pyonephrotic kidney because of recurrent problem. On the table, because a possibility of a malignnant tumor was suspected by the operating surgeon, she was subjected to right radical nephrectomy.{Figure 1}

The nephrectomy specimen weighed 800 g, measuring 17 cm × 13 cm × 7 cm in size. The oter surface was grey colored, bosselated and irregular. The cut-surface revealed multi-loculated cysts occupying the entire pelvis and the cortex was papery thin. Pus was expressed on cutting and, after pus removal, a large amount of mucin was unloaded from the pelvis [Figure 2]a. Microscopy examination revealed malignant tumor with papillary fronds of tall columnar mucin-secreting epithelium with basally located nuclei, with focal pseudostratification. Focal areas of mucin lakes with hemorrhage and necrosis were evident. The adjacent parenchyma showed changes of advanced hydronephrosis. No tumor invasion was noted in the surrounding organs/lymph nodes. Thus, it was diagnosed as mucinous cystadenocarcinoma of renal pelvis, grade 1, stage Tx N0 M0.{Figure 2}

The patient is remaining well with normal lab parameters and an unremarkable CT scan at three months of follow-up.

 Discussion



Tumors of the renal pelvis are uncommon, with a relative frequency of transitional cell carcinoma (TCC) in 90%, squamous cell carcinoma (SCC) in 10% and adenocarcinoma in <1%. [2] Mucinous cystadenocarcinoma of the renal pelvis is exceedingly rare and, to the best of our knowledge, only a total of 95 cases have been reported so far. [3] We have noted 67.9% TCC, 25% SCC and 7.1% adenocarcinoma in renal pelvic tumors studied in the last five years in our institute. Thus, it is possible that adenocarcinoma and SCC are increasing in incidence.

The usual features of mucinous cystadeno-carcinoma include long duration of symptoms, association with calculi, hydronephrosis and a pre-operative appearance of an inflammatory condition. [3] Radiological studies may not be able to identify a malignant tumor. [2] The urothelium has a particular capacity for meta-plastic response to noxious stimuli. Metaplasia in urinary tract epithelium is usually squamous; however, the occurrence of metaplastic mucin-secreting cells is also well recognized. Primary adenocarcinomas of the urinary tract exhibit a wide spectrum of glandular differentiation like enteric, mucinous, signet ring cell, clear cell, mixed or adenocarcinomas not otherwise specified. [4],[5]

Mucinous cystadenocarcinoma of the renal pelvis has a tendency to involve the broad pelvicalyceal area, assuming a flat contour conforming physical structure and, sometimes, the pathologist may not recognize its presence on gross examination of an extirpated kidney, particularly as it may be partly obscured by an infective process. [6],[7] This occurred in our case where a large amount of pus mixed with jelly-like material was expressed on cutting of the kidney and no tumor mass was noted on gross examination, and final diagnosis was only made after microscopy examination.

We suspect that this tumor is probably under-reported in view of the increasing reports of incidence of renal calculi. Also, a more focused study on its causation is needed.

Histopathology examination still remains the gold standard for the diagnosis of mucinous cystadenocarcinoma of the renal pelvis, an exceedingly rare tumor with poor prognosis that may clinically be missed due to the pre-sentation of chronic inflammatory presentation/pyonephrosis.

 Conflict of Interest



The authors declare that they have no conflict of interests.

References

1Kakkar N, Joshi K, Mandal AK. Mucinous adenocarcinoma of the renal pelvis-a case report. Indian J Pathol Microbiol 1997;40:393-5.
2Kaur G, Naik VR, Rahman MN. Mucinous adenocarcinoma of the renal pelvis associated with lithiasis and chronic gout. Singapore Med J 2004;45:1225-6.
3Takehara K, Nomata K, Eguchi J, et al. Mucinous adenocarcinoma of the renal pelvis associated with transitional cell carcinoma in the renal pelvis and the bladder. Int J Urol 2004;11:1016-8.
4Liwnicz BH, Lepow H, Schutte H, Fernandez R, Caberwal D. Mucinous adenocarcinoma of the renal pelvis: Discussion of possible pathogenesis. J Urol 1975;114:306-10.
5Shibahara N, Okada S, Onishi S, et al. Primary mucinous carcinoma of the renal pelvis. Pathol Res Pract 1993;189:946-9.
6Aufderheide AC, Streitz JM. Muncinous adenocarcinoma of the renal pelvis. Report of Two cases. Cancer 1974;33:167-73.
7Wahal KM, Kastogi BL, Mehrotra RM, Rai SC. Mucus producing adenocarcinoma of renal pelvis (report of a case and review of the literature). Indian J Pathol Bacteriol 1966;9: 352-6.