Collecting duct carcinoma of the kidney: a clinicopathological study of five cases

Cystic low-grade collecting duct renal carcinoma with liver compression — A challenging diagnosis and therapy: A case report

BACKGROUND

A collecting duct carcinoma is a very rare, malignant renal epithelial tumor. Distant metastases are present in one third of cases at the time of diagnosis. It is known to have a poor prognosis.

CASE SUMMARY

A 42-year-old male was sent to our surgery clinic for removal of a 119.2 mm × 108.3 mm encapsulated cystic mass, which was localized in the 8^th segment of the right liver lobe. The lesion was first identified on ultrasonography. A computed tomography scan confirmed the presence of a Bosniak type III cystic lesion, which affected the liver and convexity of the right kidney. Surgical intervention involved a right nephrectomy, with removal of the cystic mass. The patient was mobilized on the first postoperative day and was discharged after 7 d. The histological and immunohistochemical examination revealed a low-grade collecting duct renal carcinoma, which is a rare variant of papillary carcinoma, with low malignant potential. The patient did not receive chemotherapy and after 21 mo of follow-up, a radiological examination and laboratory analyses showed normal aspects. No relapse or other complications were reported.

CONCLUSION

To manage renal tumors properly, a correct histopathological diagnosis is crucial, as is early diagnosis and correct surgical treatment.

Sarcomatoid Renal Cell Carcinoma and Collecting Duct Carcinoma: Discrimination From Common Renal Cell Carcinoma Subtypes and Benign RCC Mimics on Multiphasic MDCT

RATIONALE AND OBJECTIVES

To investigate whether imaging features on multiphasic multidetector computed tomography (MDCT) can help discriminate sarcomatoid renal cell carcinoma (RCC) and collecting duct carcinoma (CDC) from other solid renal masses.

MATERIALS AND METHODS

With institutional review board approval for this HIPAA-compliant study, we derived a cohort of 7 sarcomatoid RCCs, 4 CDCs, 165 clear cell RCCs, 56 papillary RCCs, 22 chromophobe RCCs, 49 oncocytomas, and 16 lipid-poor angiomyolipomas with preoperative multiphasic MDCT with up to four phases (unenhanced, corticomedullary, nephrographic, and excretory). Each lesion was reviewed for contour, spread pattern, pattern of enhancement, neovascularity, and calcification.

RESULTS

Sarcomatoid RCCs and CDCs were more likely than other solid renal masses to have an irregular contour (64% vs 2%, P < 0.001) and an infiltrative spread pattern, defined as infiltration into adjacent renal parenchyma, collecting system, or neighboring structures (82% vs 7%, P < 0.001). When used to discriminate sarcomatoid RCC and CDC from other solid renal masses, an infiltrative spread pattern had a specificity of 93% (287/308) and sensitivity of 82% (9/11), and an irregular contour had a specificity of 98% (303/308) and sensitivity of 64% (7/11).

CONCLUSIONS

Solid renal lesions with an irregular contour or an infiltrative spread pattern are suspicious for sarcomatoid RCC or CDC.

A Microfluidic Method to Mimic Luminal Structures in the Tumor Microenvironment

Microscale 3D in vitro systems have attracted significant interest as tools for cancer research because the microscale systems offer better organization of the cellular microenvironment and enhance throughput of the systems by lowering costs and reducing the amount of reagents and cells. Lumens (i.e., tubular structures) are ubiquitous in vivo being present in blood vessels, mammary ducts, prostate ducts, and the lymphatic system. Lumen structures of varying size and geometry are involved in key normal and disease processes including morphogenesis, angiogenesis, cancer development, and drug delivery. Therefore, there is a need for practical methods that create various lumen structures having different size and geometries to investigate how cells in the lumen structure respond to certain microenvironmental conditions during cancer development and progression. Here, we present a method to create multiple three-dimensional (3D) luminal structures, where parameters, such as size, geometry, and distance, can easily be controlled using simple poly-dimethylsiloxane (PDMS) micro-molds.