The MSCT and MRI findings of collecting duct carcinoma

Imaging analysis of 13 rare cases of renal collecting (Bellini) duct carcinoma in northern China: a case series and literature review

Background

Collecting (Bellini) duct carcinoma (CDC) is a highly malignant and rare kidney tumor. We report our 12-year experience with CDC and the results of a retrospective analysis of patients and tumor characteristics, clinical manifestations, and imaging features by computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)/CT.

Methods

Retrospective examination of tumors between January 2007 and December 2019 identified 13 cases of CDC from three medical centers in northern China. All 13 patients underwent CT scan, among which eight underwent dynamic enhanced CT scan, two underwent PET/CT scan, and one underwent magnetic resonance cholangiopancreatography (MRCP) examination. The lesions were divided into nephritis type and mass type according to the morphology of the tumors.

Results

The study group included ten men and three women with an average age of 64.23 ± 10.74 years. The clinical manifestations were gross hematuria, flank pain, and waist discomfort. The mean tumor size was 8.48 ± 2.48 cm. Of the 13 cases, six (46.2%) were cortical-medullary involved type and seven (53.8%) were cortex–medullary–pelvis involved type. Eleven (84.6%) cases were nephritis type and two (15.4%) were mass type. The lesions appeared solid or complex solid and cystic on CT and MRI. The parenchymal area of the tumors showed isodensity or slightly higher density on unenhanced CT scan in the 13 cases. PET/CT in two cases showed increased radioactivity intake. Evidence of intra-abdominal metastatic disease was present on CT in nine (69.2%) cases.

Conclusions

The imaging characteristics of CDC differ from those of other renal cell carcinomas. In renal tumors located in the junction zone of the renal cortex and medulla that show unclear borders, slight enhancement, and metastases in the early stage, a diagnosis of CDC needs to be considered. PET/CT provides crucial information for the diagnosis of CDC, as well as for designing treatment strategies including surgery.

Clinical Features and Prognostic Outcome of Renal Collecting Duct Carcinoma: 12 Cases from a Single Institution

Purpose

Collecting duct carcinoma (CDC) is extremely rare and has high malignancy and poor prognosis. The purpose of this research is to explore the clinical characteristic, imaging, pathological diagnosis, treatment and prognostic outcome of CDCs.

Materials and Methods

The clinical data of 12 CDC cases who had been surgically treated between August 2007 and August 2017 and verified the diagnosis of CDC by postoperative pathological and/or immunohistochemical staining (IHC) results were retrospectively analyzed, and related works of literature were reviewed. And Kaplan-Meier survival analysis was used to draw the survival curve and to calculate the survival rate and the median survival time.

Results

According to the TNM stage system, 4 cases were in stage I, 2 in stage II,3 in stage III, and 3 in stage IV. On the computed tomograph and magnetic resonance imaging, CDC displayed that various shapes, unclear boundary and invasive growth into the renal parenchyma. Compared with small CDCs which did not change the contour of the kidney, large CDCs presented various imaging features. Microscopically, the typical morphology of CDCs was that collecting ducts or tubules were obviously infiltrated by tumor cells. A tubular, papillary, tubulopapillary or solid architectures with desmoplasia were often presented. And tumor cells had high-grade cytology or an infiltrative growth pattern. Necrosis of tumor cells also was common in many cases. The expression of biomarkers, such as PAX-8, INI-1, 34βE12, CK19, PAX-2, and vimentin, in most patients was detected by IHC. Eleven of all 12 cases received radical surgery, of whom 5 patients died 3–11 months after surgery, and 1 case having undergone interventional embolization therapy died at 6 months after treatment due to multiple metastases. And 1 lost to contact. The overall 1-, 2-, and 5-year survival rates were 45.5%, 36.4%, and 8.8%, respectively, and the median survival time (MST) was 11 months.

Conclusion

CDC has an aggressive clinical course, with a poor prognosis. The best way to treat CDC suspected by imaging examinations is radical surgery which can contribute to confirm the correct histopathological type. And post-operation follow-up is necessary.

Bilateral kidneys involvement of collecting duct carcinoma with cystic change: A case report

RATIONALE

Collecting duct carcinoma (CDC) is a rare neoplasm arising from the collecting duct and should be distinguished from other renal cell carcinomas that mostly originated from the proximal tubular epithelium and tumors originated from the urothelium. It usually occurs in unilateral kidney, sometimes found with cystic change.

PATIENT CONCERNS

We present the case of a 53-year-old male suffering from repeated bilateral flank pain for 6 months, increased pain with dysuria for 5 days.

DIAGNOSIS

Ultrasound showed 2 similar hybrid echo masses in bilateral kidneys with enlarged lymph nodes surrounded, which accords with magnetic resonance imaging (MRI), and intraoperative biopsy reported malignancy.

INTERVENTIONS

An exploratory operation was performed and the mass on the left kidney was removed, but pathological result reported collecting duct carcinoma according to the morphological features and immunohistochemical tests. Also postsurgery positron emission tomography-computed tomography (PET-CT) confirmed the mass on the left kidney is also a lesion of CDC.

OUTCOMES

The patient refused chemotherapy and had an overall survival of 7 months.

LESSONS

We presented a case of CDC involving bilateral kidneys with cystic change; this is the first case of bilateral renal occurrence with cystic change to our knowledge. Because of CDC's rapid growth and the lack of effective adjuvant treatment after surgery, the prognosis is poor and the diagnosis should be made carefully.

Magnetic resonance imaging (MRI) of the renal sinus

This article presents methods to improve MR imaging approach of disorders of the renal sinus which are relatively uncommon and can be technically challenging. Multi-planar Single-shot T2-weighted (T2W) Fast Spin-Echo sequences are recommended to optimally assess anatomic relations of disease. Multi-planar 3D-T1W Gradient Recalled Echo imaging before and after Gadolinium administration depicts the presence and type of enhancement and relation to arterial, venous, and collecting system structures. To improve urographic phase MRI, concentrated Gadolinium in the collecting systems should be diluted. Diffusion-Weighted Imaging (DWI) should be performed before Gadolinium administration to minimize T2* effects. Renal sinus cysts are common but can occasionally be confused for dilated collecting system or calyceal diverticula, with the latter communicating with the collecting system and filling on urographic phase imaging. Vascular lesions (e.g., aneurysm, fistulas) may mimic cystic (or solid) lesions on non-enhanced MRI but can be suspected by noting similar signal intensity to the blood pool and diagnosis can be confirmed with MR angiogram/venogram. Multilocular cystic nephroma commonly extends to the renal sinus, however, to date are indistinguishable from cystic renal cell carcinoma (RCC). Solid hilar tumors are most commonly RCC and urothelial cell carcinoma (UCC). Hilar RCC are heterogeneous, hypervascular with epicenter in the renal cortex compared to UCC which are centered in the collecting system, homogeneously hypovascular, and show profound restricted diffusion. Diagnosis of renal sinus invasion in RCC is critically important as it is the most common imaging cause of pre-operative under-staging of disease. Fat is a normal component of the renal sinus; however, amount of sinus fat correlates with cardiovascular disease and is also seen in lipomatosis. Fat-containing hilar lesions include lipomas, angiomyolipomas, and less commonly other tumors which engulf sinus fat. Mesenchymal hilar tumors are rare. MR imaging diagnosis is generally not possible, although anatomic relations should be described to guide diagnosis by percutaneous biopsy or surgery.

Comparative study of CT appearances in mucinous tubular and spindle cell carcinoma and collecting duct carcinoma of the kidney

OBJECTIVE

To characterize the multidetector CT (MDCT) imaging characteristics of mucinous tubular and spindle cell carcinoma (MTSCC) and collecting duct carcinoma (CDC) of the kidney.

METHODS

21 patients with MTSCC and 18 patients with CDC were studied retrospectively. MDCT was undertaken to investigate differences in tumour characteristics.

RESULTS

Five patients with MTSCC had calcifications as did nine patients with CDC (p = 0.108). In three patients with MTSCC and four patients with CDC, the tumours had a clear boundary (p = 0.682). No patient with MTSCC had retroperitoneal lymph node metastasis as did five patients with CDC (p = 0.015). 16 patients with MTSCC showed homogeneous enhancement, whereas 11 patients with CDC showed heterogeneous enhancement (p = 0.025). The attenuation value of CDC tumours was greater than that of MTSCC and normal renal parenchyma on an unenhanced CT (p = 0.027). MTSCC and CDC tumour enhancement was less than the normal renal cortex and medulla in all phases (p < 0.001). Tumour enhancement was greater for CDC than that for MTSCC in all phases (p = 0.011, p = 0.006 and p = 0.052).

CONCLUSION

Unenhanced and dynamic MDCT may aid in diagnosis and differentiation of MTSCC and CDC of the kidney.

ADVANCES IN KNOWLEDGE

This is the first series evaluating the imaging findings of MTSCC and CDC of which we are aware, and identification of such findings may improve diagnosis of these two rare tumours.

Collecting (Bellini) duct carcinoma: A clinical study of a rare tumour and review of the literature

INTRODUCTION

We report our 15-year experience of Collecting (Bellini) duct carcinoma (CDC). We retrospectively analyzed patient and tumour characteristics, clinical manifestations, surgical techniques, clinical outcomes, and salvage therapies.

METHODS

From January 1999 to December 2013, 1042 patients underwent surgical resection of renal neoplasm. We examined all renal tumors and identified 10 cases (0.96%) of CDC.

RESULTS

The study group included 8 men and 2 women, with a median age of 62.5 years. Of these 10 patients, 9 were symptomatic (90%). All patients were treated with open nephrectomy. The mean tumour size was 5.7 cm. The pathologic stages were distributed as follows: pT1b in 2 patients (20%); pT2a in 1 patient (10%); pT3a in 3 patients (30%); and pT3b in 4 patients (40%). Grading was assessed according to Fuhrman scale as follows: grade II in 1 patient (10%); grade III in 3 patients (30%); grade IV in 5 patients (50%); undetermined grade in 1 patient (10%). Four patients (40%) relapsed locally. The median time of local recurrence was 4.9 months. Distant metastases occurred in 9 patients (90%): 4/9 at the time of diagnosis and 5/9 after nephrectomy. The median time of distant metastases after surgery was 8.1 months. Six patients received chemotherapy (gemcitabine plus platinum salts). Radiotherapy was performed in 5 patients. One patient had surgery because of local recurrence and 2 patients were irradiated in the area of the local recurrence. The median overall survival was 7.6 months, and only 2 patients survived more than 2 years after the nephrectomy.

CONCLUSIONS

CDCs of the kidney are aggressive and they have a low survival rate. All patients in our study experienced a relapse of their disease. Local recurrence preceded distant metastases. Results of salvage treatments were poor.