Which microscopic technique is primarily used for identifying cancer cells?

The technique primarily used for identifying cancer cells is cytology. Cytology involves the examination of individual cells and their characteristics. This approach is particularly effective in detecting cancer because it allows for the analysis of cell morphology and arrangement, which are often altered in malignant cells. By studying cell samples obtained through various methods, such as fine needle aspiration or Pap smears, pathologists can identify abnormal cells indicative of cancer.

While histopathology, which examines tissue sections, is often used in cancer diagnosis as well, it focuses on the architecture of tissue and can require a more extensive sample than cytological evaluation. Immunohistochemistry is a specialized technique used in histopathology that helps to identify specific protein markers on cancer cells, enhancing the diagnosis but not being the primary technique for initial cancer cell identification. Fluorescence microscopy is a technique used for various applications, including the visualization of specific cellular components, but it is not primarily used for routine cancer cell identification.