Whereas laboratory scientists typically analyze blood or other fluids from patients, anatomic pathologists evaluate tissue specimens, which include cervical scrapings (i.e., PAP smears), biopsies, surgical resections, and whole-body evaluations at autopsy.
Anatomic Pathology has three major divisions:
Surgical Pathology. This is the examination of tissue removed as a biopsy or as part of a surgical procedure. When a biopsy is done (typically a small sampling of a lesion by incision or by an invasive technique like a core needle biopsy or endoscopy), the pathologist determines what disease process is present, and/or the extent of disease. In all cases, pathologists make their diagnoses by examining thin slices of the lesion under a microscope. Pathologists often also use a variety of specialized molecular techniques to further refine the diagnosis and to predict how the disease may respond to various types of treatment. In this way, the pathologist helps guide any subsequent therapy the patient may need.
Cytopathology: This is the examination of very small amounts of tissue removed by scraping a surface, or by aspiration through a fine needle. Obtaining a cytopathology specimen is typically less invasive than obtaining a surgical pathology specimen, so these procedures can be performed in a clinic or a physician’s office. Cytopathologists examine individual cells and small collections of cells to assess for the presence or absence of malignancy.
Autopsy Pathology: This is the anatomic examination of a deceased patient to determine what diseases were present and how extensive they were, and to assemble these findings into an explanation for why the patient died. Autopsy examination can answer questions family members may have about the patient’s death, but can also increase understanding of disease for the physicians caring for the patient.