Eosinophilic solid and cystic renal cell carcinoma with TSC2 mutation: a case report and literature review

• Published in: Diagnostic pathology Vol. 18; no. 1; p. 53
• Main Authors: He, Xin, Chen, Ying, Tang, Hao, Xu, Yujuan, Zhu, Xingyan, Wang, Caihong, Chen, Qiang, Guo, Deyu
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 25.04.2023; BioMed Central; BMC
• Subjects: Antigens; Biomarkers, Tumor - genetics; Carcinoma, Renal cell; Carcinoma, Renal Cell - genetics; Carcinoma, Renal Cell - pathology; Case Report; Case reports; Cells; Computed tomography; Cytoplasm; Diagnosis; Differential diagnosis; Disease; Eosinophilic solid and cystic renal cell carcinoma; Female; Genetic aspects; Humans; Kidney - pathology; Kidney cancer; Kidney Neoplasms - genetics; Kidney Neoplasms - pathology; Kidneys; Leukocytes (eosinophilic); Literature reviews; Lymphocytes; Metastases; Metastasis; Middle Aged; Misdiagnosis; Morphology; Mutation; Mutations; Neoplasia; Neoplasms; Nonsense mutation; Patients; Physical characteristics; Renal cell carcinoma; Soft tissues; TSC2; Tuberous Sclerosis Complex 2; Tumors; Misdiagnosis; Mutations; TSC2; Case report; Eosinophilic solid and cystic renal cell carcinoma; Renal cell carcinoma
• ISSN: 1746-1596; 1746-1596
• DOI: 10.1186/s13000-023-01341-9

Eosinophilic solid and cystic renal cell carcinoma (ESC-RCC) is an under-recognized, emerging new entity of sporadic renal neoplasms, which is listed as a rare type of renal cell carcinoma in the 2022 WHO renal tumor classification. It is easily misdiagnosed because its characteristics are insufficiently understood. We report one case of ESC-RCC, a 53-year-old female patient with a right kidney mass found during clinical examination. The patient experienced no discomforting symptoms. Computer-tomography imaging at our urinary department showed a round soft tissue density shadow around the right kidney. Microscopic examination revealed a tumor displaying a solid-cystic composition of eosinophilic cells with unique features, revealed by characteristic immunohistochemical markers (CK20-positive/CK7-negative), and a nonsense mutation in TSC2. Ten months after the renal tumor resection, the patient presented in good condition with no recurrence or metastasis. The distinct morphological, immunophenotypic, and molecular characteristics of ESC-RCC we describe here, based on our case and the relevant literature, highlight the key points of the pathological and differential diagnosis of this novel renal neoplasm. Our findings will therefore deepen our understanding of this novel renal neoplasm and help reduce misdiagnosis.