Microscopy

 nests of polygonal, clear to eosinophilic cells associated with a subpopulation of smaller cells that surround hyaline material.
 epithelioid morphology
 the hyaline material is positive with periodic acid-Schiff and methenamine-silver histochemical stains

Immunochemistry

 HMB45+
 melan-A+
 EMA-
 the hyaline material labels immunohistochemically for type 4 collagen

Ultrastructure

 hyaline material represents basement membrane material.

Cytogenetics

t(6;11)(p21.1;q12) (#11395386#)

Molecular biology

 fusion gene TFEB-alpha between TFEB at 11q12 (MIM.600744) and alpha at 6p21 (MIM.607924)

References

 Argani P, Lae M, Hutchinson B, Reuter VE, Collins MH, Perentesis J, Tomaszewski JE, Brooks JS, Acs G, Bridge JA, Vargas SO, Davis IJ, Fisher DE, Ladanyi M. Renal carcinomas with the t(6;11)(p21;q12): clinicopathologic features and demonstration of the specific alpha-TFEB gene fusion by immunohistochemistry, RT-PCR, and DNA PCR. Am J Surg Pathol. 2005 Feb;29(2):230-40. PMID: #15644781#

 Bruder E, Passera O, Harms D, Leuschner I, Ladanyi M, Argani P, Eble JN, Struckmann K, Schraml P, Moch H. Morphologic and Molecular Characterization of Renal Cell Carcinoma in Children and Young Adults. Am J Surg Pathol. 2004 Sep;28(9):1117-1132. PMID: #15316311#

 Davis IJ, Hsi BL, Arroyo JD, Vargas SO, Yeh YA, Motyckova G, Valencia P, Perez-Atayde AR, Argani P, Ladanyi M, Fletcher JA, Fisher DE. Cloning of an Alpha-TFEB fusion in renal tumors harboring the t(6;11)(p21;q13) chromosome translocation. Proc Natl Acad Sci U S A. 2003 May 13;100(10):6051-6. Epub 2003 Apr 28. PMID: #12719541#

 Argani P, Hawkins A, Griffin CA, Goldstein JD, Haas M, Beckwith JB, Mankinen CB, Perlman EJ. A distinctive pediatric renal neoplasm characterized by epithelioid morphology, basement membrane production, focal HMB45 immunoreactivity, and t(6;11)(p21.1;q12) chromosome translocation. Am J Pathol. 2001 Jun;158(6):2089-96. PMID: #11395386#