Hales colloidal iron

Author: Nat Pernick, M.D. (see Authors page)

Revised: 24 November 2015, last major update June 2005

Copyright: (c) 2003-2015,, Inc.

PubMed Search: colloidal iron[title]

Definition / General
  • Kidney tumors: stain must have pH between 1.5 and 2.0
  • Clear cell and papillary renal carcinoma have focal, coarse, droplike staining
  • Note: hemosiderin in any tumors will also stain positive
Uses by Pathologists
  • Helpful in distinguishing chromophobe renal cell carcinoma (intensely positive in large percentage of cells with reticular staining) from oncocytoma (usually negative; if positive - fewer cells with less intensity and dustlike staining)