Generally, laboratorial processes are subdivided into three sequential stages: pre-analysis (encompassing the collection, transport, and specimen storage), analytic (laboratory processing itself), and post-analysis (encompassing the interpretation of the results and the expert’s opinion). Regarding the pathological anatomy, material’s fixation in formalin is the main pre-analysis step, as the specimen disposed in formalin and paraffin included is the universal standard of tissue processing to undergo histopathological analysis. The proper fixation enables the architectural preservation of the cytological characteristics of tissues, crucial to the adequate morphological diagnosis, and consists in the standard preparation of the tissues for immunohistochemical (IHQ) analysis and other techniques such as hybridization in situ (HIS).
KeywordsSurgical specimen Clinical examination Pathological analysis Immunohistochemical Formalin fixation
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