Renal myxoma: A report of two cases and review of the literature

Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
American Journal of Surgical Pathology (Impact Factor: 5.15). 03/1994; 18(2):187-94.
Source: PubMed


Renal myxomas are rare neoplasms. Seven cases have been reported, of which only two are convincingly diagnosed as myxoma; the remaining cases exhibit features of sarcoma, fibroepithelial polyp, or myxolipoma. We report two additional cases; one in a 52-year-old man and another in a 68-year-old woman. They were discovered incidentally by radiological examination. The resected kidney in both patients contained a well-demarcated gelatinous intraparenchymal tumor, which consisted of occasional slender spindle cells scattered in an abundant myxoid stroma, closely resembling myxomas of other sites. The tumor cells showed immunoreactivity for vimentin but not for S-100 protein, epithelial membrane antigen (EMA), CAM 5.2, HHF-35, or smooth muscle actin. Ultrastructural features were of fibroblast-like cells with an elaborate network of cytoplasmic processes. The differential diagnosis of myxoid tumors of the kidney includes myxoid variants of renal sarcomas and carcinomas, renomedullary interstitial cell tumors, and fibroepithelial polyps. It is important to recognize the existence of a renal myxoma, to avoid confusing this benign tumor with the malignant neoplasms with secondary myxoid features that may involve the kidney.

1 Follower
4 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Myxomas are relatively rare tumors and most of them occur in the heart, skin, and soft tissues and bones. Renal myxomas are extremely rare neoplasms and very few cases have been reported in the literature. A review of medical literatures reveals no previous description of renal myxoma complicated with extensive areas of hemorrhage. So, we report such a case in a 43-year-old female. She had a left renal mass incidentally discovered during ultrasonography at a regular health checkup, and further computed tomography scan showed 4.9 × 3.1 cm mass with circular septal enhancement and ill-defined margin with the left psoas major muscle. Radical nephrectomy was performed because of suspected malignant renal tumor. Postoperative histopathology of resected specimen revealed the typical appearance of a myxoma associated with extensive hemorrhage.
    Indian Journal of Surgery 06/2013; 75(1). DOI:10.1007/s12262-013-0862-z · 0.26 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Renal schwannomas are extraordinarily rare neoplasms; only six have been reported, the majority of which occurred in the renal pelvis. We report the clinical and pathologic features of four additional cases. The resected kidney in all patients contained a well-demarcated, yellow-tan, smooth, and bulging intraparenchymal tumor (mean size, 9.7 cm; range, 4 to 16 cm). Microscopically, three cases were classified as cellular schwannomas, and one was a usual-type schwannoma, with degenerative nuclear atypia. By immunohistochemistry, all tumors were strongly S-100 protein positive and negative for pan-cytokeratin, CD57, smooth muscle actin, desmin, and CD34. Epithelial elements were not noted in the tumors, and there was no history of any clinical syndromes in these patients. Analysis of the four cases showed the mean age at presentation to be 47 years (range, 18 to 84 years), with no sex predisposition (two men, two women). Most patients were asymptomatic, and all received a diagnosis of renal cell carcinoma and treated as having such. Recognition and awareness of these rare, benign tumors will assist in the differential diagnosis of spindle cell tumors of the kidney and prevent their misdiagnosis as sarcomatoid carcinomas of the kidney or renal sarcomas. Our study, the largest series to date of renal schwannomas, demonstrates a predilection for the cellular variant in the kidney, documents that these tumors may present in the nonhilar region of the kidney, and provides clinical evidence of their benign biologic behavior.
    Modern Pathology 09/2000; 13(8):851-6. DOI:10.1038/modpathol.3880150 · 6.19 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Myxomas are uncommon soft-tissue neoplasms, which are extremely rare in the kidney, with only five cases documented in the intraparenchymal location. However, renal capsular myxoma has not yet been reported. We describe a unique case of a clinically detected renal myxoma arising in the capsule. A 37-year-old man receiving treatment for epididymitis sought medical assistance for infertility. A radiological examination incidentally discovered a right renal tumor. The mass intruded into the perirenal tissue and measured 6 cm in major diameter. The resected kidney contained a well-circumscribed gelatinous capsular tumor. It was composed of sparse, bland, slender, spindle-shaped cells scattered in large amounts of basophilic interstitial mucoid material. The tumor cells showed diffuse immunoreactivity for vimentin. Occasional cells stained for alpha-smooth muscle actin and calponin. Reactivity was negative for S100 protein, epithelial membrane antigen, pancytokeratin, neurofilament protein, and h-caldesmon antibodies. Ultrastructural examination revealed fibroblast-like cells with long thin cytoplasmic processes, prominent rough endoplasmic reticulum, a well-developed Golgi complex, and secretory vesicles. No basal lamina was identified around the tumor cells. The differential diagnosis includes many other benign and malignant soft-tissue lesions exhibiting prominent secondary myxoid features. It is important to consider a renal capsular myxoma when examining lesions at this anatomic site to avoid misdiagnoses and to ensure that the patient receives appropriate treatment and prognostic information.
    Pathology - Research and Practice 02/2005; 200(11-12):835-40. DOI:10.1016/j.prp.2004.10.002 · 1.40 Impact Factor
Show more