Woo Gyeong Kim, Gregory Imhagwe

Anatomic Pathology, Australian Clinical Labs, Clayton, VIC, Australia. 

Background: Bilateral synchronous malignant and or benign renal neoplasms have been defined. Yet, unilateral concurrent clear renal cell carcinoma (CRCC) and papillary adenoma (PA) coexisting in 1 mass is very rare and has not been previously reported. 

Case Presentation: We report a case of a 68-year-old male who underwent a partial nephrectomy for a 65mm mass in the left kidney. Macroscopically, a multiloculated cystic mass confined to renal parenchyma with variegated colors was present and at the periphery of the mass, a solid white 10mm lesion was identified. Microscopy revealed 2 different patterns - the main tumour was a 65mm typical CRCC and the peripheral lesion was a PA with a diameter of 9mm. Immunohistochemistry of CK7 was strong positive in PA and negative in CRCC whereas CA IX showed opposite staining. AMACR was expressed in both patterns, with much stronger intensity in PA. 

Conclusion: We present a rare case of concurrent synchronous malignant CRCC and benign PA in unilateral kidney.  To the best of our knowledge, there has not been a report of a coexisting CRCC and PA within the same mass.  

1. Patel MI, Simmons R, Russo P, et al. Long-term follow-up of bilateral sporadic tumous. Urology 2003; 61(5): 921-925.

2. Ustuner M, Yaprak B, Culha M, et al. Coexisting papillary and clear renal cell carcinoma in the same kidney. Case Rep Urol 2014; 2014: 575181.

 

Contribution: WGK contributed to writing this manuscript and GI conducted ancillary studies and made final diagnosis of this case. All authors reviewed the abstract.  

 

 

I declare that the following statements are true to the best of my knowledge with regard to the submission of this abstract. 

1. I am the person who wrote this abstract originally.

2. I agree to submit this abstract to the Pathology Update 2025 conducted by Royal College of Pathologists Australasia. 

3. I certify that this is the original abstract. It has not been previously published and is not currently under submission in other competition or elsewhere.

Sign: 

Name: Woo Gyeong Kim

Date: 21/10/2024