Summary: Surgical histopathology investigations plays a key role in diagnostics of neoplastic diseases. Traditional histopathological and cytological approach using histological techniques and staining methods, complemented by immunohistochemical detection of proteins in tissues represent the basic principles in diagnostics. The spectrum of investigations is broadened by methods identifying changes in tumor cells at the level of mRNA and DNA (a vertical aspect), and in near future will be expanded by detection of groups of genes or their products at one time – microchip technologies (a horizontal aspect). Examples based on a practical use of modern diagnostic approaches serve to illustrate a trend to introduce a spectrum of investigations performed by departments of pathology, which should maintain a role of a basic laboratory discipline. It is to be stressed that beside a diagnostic importance of molecular investigations there is an increasing importance of investigations aimed at molecular therapy (eg. detection of ERBB-2 protein and ERBB2 gene in patients with invasive duct carcinomas of the breast). A continuous training in the field of pathology and molecular biology is a prerequisite for longevity of any pathologist.
How to survive in the vastness of molecules: a view from a pathologist
