Comparison of Renal Anastomosing Hemangiomas in End-Stage and Non-End-Stage Kidneys: A Meta-Analysis With a Report of 2 Cases.

BACKGROUND: Renal anastomosing hemangioma (RAH) is a very rare distinct entity composed of anastomosing sinusoidal (spleen-like) capillary-sized vessels lined by flat or hobnail endothelial cells. Most of the published cases of RAH occurred in the setting of end-stage renal disease (ESRD). METHODS: We present 2 cases of RAH in ESRD along with a literature review. We compared clinicopathologic features of RAHs in end-stage and non-end-stage kidneys. A meta-analysis was conducted with PubMed and a manual search through references of relevant publications. Individual patient data gathered from the literature were used in the analysis. RESULTS: Our systematic review revealed 49 RAHs, including our 2 cases. Thirty-two (65.3%) cases were in ESRD, only 17 (34.7%) were in patients with non-ESRD. RAHs in ESRD were in younger patients, smaller in size, multifocal, and seen more with renal epithelial neoplasms when compared with RAHs in non-ESRD ( P < .05). Extramedullary hematopoiesis was seen mostly in RAHs in ESRD kidneys (85% vs 41.7%) ( P = .018). Follow-up data were available for 25 cases with a mean follow-up of 24.58 ± 38.54 months. Recurrence, metastasis, or death have never been described related to RAH in any patients. CONCLUSIONS: In conclusion, RAHs are rare and mostly arise in kidneys with end-stage damage. RAHs in ESRD and non-ESRD differ in terms of clinicopathologic features.

Renal carcinoma associated with a novel succinate dehydrogenase A mutation: a case report and review of literature of a rare subtype of renal carcinoma.

Renal cell carcinoma (RCC) linked to germline mutation of succinate dehydrogenase subunits A, B, C, and D (SDHA, SDHB, SDHC, and SDHD, respectively) has been recently included as a provisional entity in the 2013 International Society of Urological Pathology Vancouver classification. Most SDH-deficient tumors show SDHB mutation, with only a small number of RCC with SDHC or SDHD having been reported to date. Only one case of SDH-deficient renal carcinoma known to be SDHA mutated has been previously reported. Here we report an additional RCC harboring an SDHA mutation occurring in a 62-year-old man with right flank pain and nodal metastasis. The tumor was characterized by an infiltrative pattern with solid, acinar, and papillary components. Loss of SDHA and SDHB protein by immunohistochemistry confirmed the diagnosis. Hybrid capture-based comprehensive genomic profiling identified 3 genomic alterations in tumor tissue: (i) a novel single-nucleotide splice site deletion in SDHA gene, (ii) single-nucleotide deletion in NF2 gene, and (iii) EGFR gene amplification of 19 copies. This is the second report of SDHA-mutated RCC. With increased awareness, this rare tumor can be recognized on the basis of distinctive morphology and confirmation by immunohistochemistry and genomic profiling.