Tissue samples include, for example, skin specimens such as removed moles, biopsy samples taken from lumps, samples collected during endoscopic procedures, or organs removed during surgery. Cell samples include fine-needle aspiration samples, sputum and urine samples, and gynecological exfoliative cytology samples, such as pap smears.
Tissue or cell samples may be collected in primary health care, during outpatient visits at hospitals, and in more complex cases under image guidance in radiology or surgically in operating rooms. Samples are also collected at laboratory service units.
A biopsy from a tumor can be taken using a biopsy needle or a punch biopsy from the skin. Depending on the sampling site, either a tissue or cell sample may be collected. A cell sample is aspirated from the tumor using a thin needle, but its diagnostic value is often limited. A more accurate diagnosis is often achieved with a slightly larger tissue sample, known as a core needle biopsy.
All samples are examined and reported in the pathology laboratory.