Archives of Pathology & Laboratory Medicine
Context: Renal cell carcinoma with fibromyomatous stroma (RCC-FMS) is a provisional entity of renal cell neoplasm that can be difficult to distinguish from low-grade clear cell RCC and clear cell papillary renal cell carcinoma (CCP-RCC) owing to its fibromyomatous stroma, low-grade nuclei, and clear cell cytoplasm.
Design: In this pilot study, we evaluated the utility of GATA3 and CD133 (a stem cell marker) as immunostain markers for the standard panel of cytokeratin 7 (CK7), CD10, and CAIX in distinguishing RCC-FMS from clear cell RCC and CCP-RCC. We stained 6 RCC-FMSs, 5 clear cell RCCs, and 5 CCP-RCC samples for all 5 markers and analyzed the results.
Results: The RCC-FMS samples were positive for CK7, CD10, CAIX, and CD133 but negative for GATA3. Clear cell RCC samples were negative for CK7 but positive for CD10 and CAIX, and negative for both GATA3 and CD133 (Table). CCP-RCC samples were positive for CK7 and CAIX (cup shape) but negative for CD10, and positive for both GATA3 and CD133. Our pilot study showed that adding GATA3 and CD133 stains to the standard marker expressions of CK7, CD10, and CAIX can provide additional evidence to distinguish RCC-FMS from clear cell RCC and CCP-RCC. However, it is important to note that this study is limited by the small sample size and further research is needed to confirm these findings.
Conclusions: GATA3 and CD133 immunostains can be useful in distinguishing RCC-FMS from clear cell RCC and CCP-RCC. This may improve diagnostic accuracy and aid in the management of patients with this type of neoplasm.
Metcalf B, Feng J, Chen L, Pansare V, Zhang PL. Renal cell carcinoma with fibromyomatous stroma has a distinctive staining pattern with GATA3 and CD133 from clear cell RCC and clear cell papillary RCC (CCP-RCC). Arch Pathol Lab Med. 2023 Sep;147(9):e60. doi:10.5858/arpa.2023-0258-AB