Biopsy
In the 12th century, an Arab physician named Abulcasis used a needle to puncture a patient's thyroid gland. This early procedure helped him characterize many types of goiter and marked one of the first diagnostic biopsies in history. The method involved extracting fluid or tissue from within the body for examination. Later, the French dermatologist Ernest Besnier introduced the word biopsy to the medical community in 1879. He derived the term from Greek words meaning life and sight. This linguistic shift reflected a growing ability to examine living tissue without killing the subject.
A surgeon may remove an entire lump during what is called an excisional biopsy. When the specimen is evaluated, the amount of uninvolved tissue around the lesion is examined to see if disease has spread beyond the area. Clear margins mean no disease was found at the edges of the biopsy specimen. Positive margins indicate that disease was found, requiring a wider excision depending on the diagnosis. In contrast, an incisional biopsy takes only a wedge of tissue when intact removal is not indicated. A core biopsy uses devices that bite into the lumen to collect samples of varying sizes. Smaller diameter needles perform fine needle aspiration biopsies to collect cells without preserving histological architecture.
Pathologists analyze surgical margins to determine how far cancer has spread through tissue. Examination of the full mastectomy specimen confirms the exact nature of breast cancer after a previous nonexcisional biopsy established the initial diagnosis. The pathologist looks for sub-classification of tumor and histologic grading to reveal the extent of its spread. This process helps stage the disease accurately before further treatment decisions are made. Surgeons rely on these reports to decide whether additional surgery or chemotherapy is necessary for the patient.
Liquid biopsy methods provide a non-invasive alternative to repeat invasive biopsies for monitoring cancer treatment. These blood tests detect circulating tumor cells and cell-free circulating tumor DNA in real time. Companies like Guardant Health offer next generation sequencing testing for advanced cancer patients. A 2014 study analyzed the blood of 846 patients across 24 institutions to detect cancer DNA presence. Researchers found tumor DNA in more than 80 percent of patients with metastatic cancers. They also detected it in about 47 percent of those with localized tumors. Such tests may assess whether malignant cells remain after tumors have been surgically removed.
Biopsy specimens are often taken from part of a lesion when the cause of a disease remains uncertain. Flexible endoscopy enables access to the upper and lower gastrointestinal tract through the mouth and rectum. Biopsies of the liver determine response to therapy by assessing reduction of inflammation and progression of fibrosis. In hepatitis, most biopsies are not used for diagnosis but rather to track therapeutic outcomes. Testicular biopsies evaluate male fertility when sperm quality is low despite normal hormone levels. Kidney biopsies use fluorescence microscopy to diagnose alterations of renal function such as Crescentic glomerulonephritis.
After removal, the tissue sample travels to the pathology laboratory for processing. The lab receives the biopsy and creates an extremely thin slice attached to a glass slide. Any remaining tissue is saved for later studies if required. Dyes stain the tissue so individual cells become visible under magnification. A pathologist examines the slide looking for any abnormal findings before preparing a report. This document lists all important or abnormal results found during the microscopic examination. The final report goes directly to the surgeon who originally performed the procedure on the patient.
Common questions
Who introduced the word biopsy to the medical community in 1879?
The French dermatologist Ernest Besnier introduced the word biopsy to the medical community in 1879. He derived the term from Greek words meaning life and sight.
What is the difference between an excisional biopsy and an incisional biopsy?
A surgeon may remove an entire lump during what is called an excisional biopsy, whereas an incisional biopsy takes only a wedge of tissue when intact removal is not indicated. Clear margins mean no disease was found at the edges of the biopsy specimen while positive margins indicate that disease was found requiring a wider excision depending on the diagnosis.
How accurate are liquid biopsy blood tests for detecting cancer DNA in patients with metastatic cancers?
Researchers found tumor DNA in more than 80 percent of patients with metastatic cancers in a 2014 study analyzing the blood of 846 patients across 24 institutions. These blood tests detect circulating tumor cells and cell-free circulating tumor DNA in real time to assess whether malignant cells remain after tumors have been surgically removed.
When do pathologists examine surgical margins to determine how far cancer has spread through tissue?
Pathologists analyze surgical margins to determine how far cancer has spread through tissue after a biopsy specimen travels to the pathology laboratory for processing. The lab creates an extremely thin slice attached to a glass slide and uses dyes so individual cells become visible under magnification before preparing a report.
What specific organs receive biopsies to evaluate fertility or renal function?
Testicular biopsies evaluate male fertility when sperm quality is low despite normal hormone levels, and kidney biopsies use fluorescence microscopy to diagnose alterations of renal function such as Crescentic glomerulonephritis. Biopsies of the liver determine response to therapy by assessing reduction of inflammation and progression of fibrosis.