Macroscopic examination of endocrine specimens: a critical appraisal

Meticulous macroscopic examination is the cornerstone of histopathology reporting because macroscopically missed abnormalities are unlikely to be identified by microscopic examination. In this review, we critically discuss some general issues around macroscopy that have been insufficiently addressed in the literature and then focus on specific issues related to the macroscopic examination of the thyroid, parathyroid and adrenal glands. The importance of the clinical context, optimal specimen fixation, clinically focused macroscopic descriptions and judicious tissue sampling is emphasized. Specimens resulting from therapeutic procedures generally require only limited sampling. Targeted sampling is key as even complete submission would result in microscopic evaluation of only about 0.2% of a specimen. Some issues with current guidance such as recommendations based on the number of blocks to be submitted per centimetre maximum tumour dimension are also discussed. The amount of tissue submitted in a cassette is very variable and it is unclear whether “block” refers to a tissue block or a paraffin block. Two pieces of tissue in a cassette would result in two blocks of tissue in a single paraffin block.