Pathology, translated etymologically means “the study of disease.” The word carries a lot of weight. After all, “the study of disease” is the foundation and inspiration of basically all of medicine and biomedical science. The desire and effort to understand how and why diseases occur has probably existed for as long as civilization.
Although the pure etymological definition of pathology is the study of disease, most pathologists don’t actually spend their time studying diseases. We study tissue, to diagnose diseases and identify prognostic features. The fact that we are still called pathologists dates to when microscopic examination of affected tissue was essentially the only way of studying and characterizing diseases beyond history and physical examination.
Many diseases are still diagnosed by their microscopic features, cancer being perhaps the most prominent example. But since the days of Rudolph Virchow, the mechanisms of many diseases which were previously characterized only microscopically became better understood. With the acceptance of the germ theory of disease and with developments in biochemistry and immunology, pathophysiology could be explained by mechanisms which are often not apparent at the microscopic level.
The historical preeminence of histology in the characterization of diseases lives on today in the way medical students are educated. The fact that pathology is a core discipline of medical school pre-clinical education (years 1 and 2) reflects an acceptance among physician educators that the appearance of diseased tissue at the microscopic level, in the realm of about 40x-400x, after being fixed in formalin, embedded in paraffin, sectioned at approximately 7 micron thickness, and colorized with pink and blue stains, contains a fundamental truth about what a disease essentially is.
Of course, only those medical students who will specialize in pathology will actually interpret histopathology once they are physicians. Perhaps this is why pathology has become less emphasized in many medical schools compared to its prominence in the past. Nonetheless, it remains entrenched in the curriculum, and Robbins Basic Pathology remains an essential text for medical students. Despite this emphasis during medical school on teaching classic histologic appearances of diseases, most students graduate medical school without having much of a clue about what pathologists actually do, what real microscopic interpretation entails, and what information pathologists can provide.
Perhaps pathologists involved in medical school education and USMLE Step 1 test development should focus more on understanding principles of specimen evaluation and terminology of pathology reports, to facilitate professional interaction and communication in the future. While only those who pursue a pathology residency will interpret tissue at the microscopic level, almost all physicians will rely on pathology reports and conversations with pathologists to help manage their patients.
[Photo is courtesy of the Huffington Post: http://www.huffingtonpost.ca/kathy-buckworth/teacher-gifts_b_5521055.html]