Review of Biopsy Techniques
Review of Biopsy Techniques
The term “biopsy” refers to the removal of living tissue from a patient for the purpose of microscopic “examination.” The word “biopsy” is associated in minds as “a test for cancer.” While it is often used to rule out the presence of malignancies, it is more commonly used for the diagnosis of conditions where cancer is not at issue.
Excisional Biopsy –In ideal circumstances, an entire lesion is removed and submitted for microscopic examination — an excisional biopsy. If complete removal is confirmed by microscopic examination, the patient may need no further treatment. With excisional biopsies, microscopic diagnosis is based on examination of the entire lesion. As ideal as excisional biopsies are, they are limited to small lesions located in areas that do not require specialized surgery.
Incisional Biopsy — When excision of a lesion cannot be accomplished easily, the next best thing is to remove and submit a portion of it for microscopic examination; a procedure known as “incisional biopsy.” Candidates for incisional biopsy are lesions too large to be entirely removed, lesions that are in inaccessible locations, lesions that are close to important anatomic structures, or in the instance that the surgeon requires a definitive diagosis in order to plan further care. Because only a portion of a lesion is removed, the microscopic diagnosis will be based upon the submitted sample. While it is sometimes difficult to determine where the most representative sample should be taken, those experienced in the clinical appearance of oral lesions can make a fairly accurate educated guess. With large lesions, they may make several incisions to increase the likelihood of submitting a representative sample(s).
Fixation — Removed lesions must be placed immediately in a solution that immediately “fixes” cells in their living appearance. The standard solution is 10% formalin that is provided in our biopsy kit. It is also important that enough formalin is used: at least 20 times formalin volume to the tissue volume.