Short answers, pulled from the story.
A biopsy is a medical test in which sample cells or tissues are extracted from the body and examined, typically under a microscope by a pathologist. Biopsies are most commonly performed to determine the presence or extent of a disease, particularly cancer or inflammatory conditions.
The French dermatologist Ernest Besnier introduced the word biopsie to the medical community in 1879. The term derives from the Greek words bios, meaning life, and opsis, meaning a sight.
An excisional biopsy removes the entire lesion or suspicious area, and the surgeon examines the surrounding margin to determine whether the disease has spread beyond the removed tissue. A core biopsy uses a needle to sample a portion of the abnormal tissue without attempting to remove the whole lesion.
A liquid biopsy is a blood test that detects cancer by analyzing either circulating tumor cells or cell-free circulating tumor DNA, rather than removing tissue. It is not a biopsy in the traditional sense because no tissue sample is taken.
A 2014 study of 846 patients with 15 types of cancer across 24 institutions found tumor DNA in more than 80 percent of patients with metastatic cancers and in about 47 percent of those with localized tumors, with no false positives produced.
The Arab physician Abulcasis, who lived from 1013 to 1107, performed one of the earliest diagnostic biopsies. He used a needle to puncture the thyroid and characterized many types of goiter based on his findings.