Collision tumor of the kidney composed of clear cell carcinoma and collecting duct carcinoma: report of a case with unusual morphology and clinical follow-up

Urothelial Carcinoma of the Renal Pelvis with Synchronous Ipsilateral Collecting Duct Carcinoma: Two Case Reports

Synchronous renal malignancies are seldom encountered or diagnosed post-renal resection. A combination of renal cell carcinoma (RCC) and urothelial carcinoma (UC) is most commonly reported. Typically, the RCC subtype is clear-cell RCC; however, a combination of collecting duct carcinoma (CDC) and UC has rarely been reported in the existing literature. Here, we present two cases of synchronous renal malignancy, specifically a combination of CDC and UC, in the ipsilateral kidney.

Acquired Perforating Dermatosis as a Paraneoplastic Feature: A Case Report, Literature Review, and Novel Association

Kyrle's disease is an uncommon form of acquired transepidermal elimination dermatosis frequently associated with diabetes mellitus and chronic kidney disease. An association with malignancy has been sporadically reported in the literature. Here, we describe the clinical course of a diabetic patient with end-stage renal disease who developed this disorder as a herald to a regionally advanced renal cell carcinoma. We provide a focused literature review and rationale for the definitive categorization of acquired perforating dermatosis as a potential paraneoplastic manifestation of systemic malignancies. Clinicopathological correlation and prompt communication among clinicians for occult malignancies are always warranted. Furthermore, we describe a novel association of one of the subtypes of acquired perforating dermatosis with such malignancies.

Collision Carcinoma Involving Small Cell Neuroendocrine Carcinoma and Squamous Cell Carcinoma of the Ureter: A Case Report and Review of the Literature

Background

Small cell neuroendocrine carcinoma (SCNEC) of the ureter is a rare tumour, accounting for less than 0.5% of all ureteral tumours. SCNEC tumours are highly aggressive and patients have a poor prognosis. Ureteral SCNEC colliding with other pathological types of tumours is extremely rare. In this paper, we present the case of a patient with ureteral small cell carcinoma colliding with squamous cell carcinoma and review the literature regarding the clinicopathological features, treatment and prognosis of thus tumour. To the best of our knowledge, this is the second identified case of ureteral SCNEC colliding with SCC.

Case Presentation

A 64-year-old male patient presented with a history of 1 month of gross haematuria and 3 months of left flank pain. CT urography revealed a soft tissue mass in the upper ureter, which was slightly enhanced on contrast-enhanced CT. Nephroureterectomy was performed after the patient was diagnosed with a tumour in the left ureter. Microscopy and immunohistochemical examination confirmed the mass to be a SCNEC collision with SCC. Two months after the surgery, the patient received adjuvant chemotherapy (cisplatin/etoposide). After 14 months of follow-up, no local recurrence or distant metastasis was found.

Conclusion

Ureteral collision carcinoma with SCNEC predominantly occurs in Asian individuals, is difficult to diagnose preoperatively and is highly invasive. The current management of ureteral collision carcinoma is a comprehensive treatment based on surgery.

Open partial nephrectomy for a collision renal cell carcinoma in a transplant kidney: A case report

A collision tumour of the kidney is a very rare condition defined by two immediately adjacent but histologically distinct neoplasms that coexist within one organ without histological admixture. We present a collision tumour in a transplant kidney treated with open partial nephrectomy. This case also highlights key surgical principles the enhanced risk of oncogenesis in transplant recipients, and some key principles for surgical resection of a tumour in a transplant kidney.

Aggressive co-existence: Collecting duct and clear cell carcinoma in the same kidney

As in every organ, synchronous multiple cancers are rarely encountered in kidneys. In the literature, mostly co-existence of renal cell carcinoma and transitional cell carcinoma was reported. In the literature, the co-existence of collecting duct carcinoma and clear cell carcinoma was described only for a few cases with different patterns. With these two cases, we aimed to present a very rare entity with synchronous existence of clear cell renal cell carcinoma and collecting duct carcinoma in the same kidneys.

A Composite Renal Tumor with Dual Differentiation, Chromophobe and Collecting Duct Carcinoma

Chromophobe carcinoma constitutes a small subset of all renal carcinomas. Within this category, rare tumors with divergent differentiation have been recognized. Herein, we report a rare case of composite chromophobe and collecting duct carcinoma and describe its pathologic and clinical features.

A collision tumor of papillary renal cell carcinoma and oncocytoma: case report and literature review

OBJECTIVES

The most common renal neoplasms include clear cell, chromophobe, and papillary renal cell carcinomas (PRCCs) and oncocytomas. While lesions containing hybrid features of different tumor types, such as hybrid oncocytic tumors, have been well documented in the literature, the finding of a collision tumor of two distinct tumor types- PRCC and oncocytoma-is extremely rare.

METHODS

We present a case of PRCC associated with an oncocytoma. Our discussion includes a review of the available literature on this rare type of collision tumor.

RESULTS

Prosection of a partial nephrectomy performed in a 78-year-old man for painless gross hematuria and nocturia revealed a 6.4 × 5 × 3.6-cm well-delineated orange to yellow-tan mass harboring a white-tan 1 × 0.9 × 0.9-cm mass. Histologic diagnosis of PRCC associated with an oncocytoma was rendered. By immunohistochemistry, focal CK7 expression was present in the oncocytoma, while strong diffuse positive CK7 expression was present in the PRCC component. Fluorescence in situ hybridization (FISH) revealed trisomy 17 in 39.3% of PRCC tumor nuclei but no significant chromosomal aberration in oncocytoma.

CONCLUSIONS

In view of this and previously reported cases, thorough sectioning and examination, especially in large oncocytomas, is recommended to exclude the presence of an associated malignancy. To our knowledge, trisomy 17 by FISH has not been previously reported in these extremely rare tumors.