Lymphomas are a type of cancer that occurs in the lymphatic system. The lymphatic system includes small clusters of immune cells called lymph nodes, which often become involved in lymphoma. When a patient is suspected of having a lymphoma, physicians commonly recommend a biopsy to aid in the diagnosis.
Diagnosis
A biopsy, according to the American Cancer Society, becomes necessary to accurately diagnose a lymphoma. Biopsies allow physicians to get a sample of cells from a swollen lymph node in order to examine them under a microscope. This allows doctors to look for changes in the lymph nodes, such as abnormal cells, which can indicate lymphoma. A lymph node biopsy proves important because many of the symptoms of a lymphoma, including swollen lymph nodes, can also result from infections.
Hodgkin's Vs. Non-Hodgkin's
A biopsy can also let doctors distinguish between Hodgkin's and non-Hodgkin's lymphoma. Hodgkin's lymphoma is distinguished from other kinds of lymphoma by the presence of special cells called Reed-Sternberg cells, the National Cancer Institute explains. Biopsies can also determine the type of Non-Hodgkin lymphoma. According to the Leukemia and Lymphoma Society, fourteen different kinds of non-Hodgkin's lymphoma exist, and the exact subtype can be determined via analysis of a biopsy. Diagnosis of the exact type of lymphoma proves critical to receive the proper treatment.
Biopsy Types
There are two main ways in which tissue samples for a lymphoma biopsy can be obtained, the American Cancer Society explains. With an excisional biopsy, a surgeon will cut into the skin to remove all or part of a lymph node for further analysis. Fine needle aspiration, on the other hand, uses a needle, which can then take a sample of the lymph node tissue. This type of biopsy does not require surgery but obtains less tissue.
Biopsy Testing
There are a variety of tests performed on tissue samples from a lymph node biopsy, the American Cancer Society explains. Immunohistocytochemistry uses special proteins, which bind to molecules on the surface of the biopsy sample. Flow cytometry uses similar proteins and a laser beam to analyze the types of cells in the biopsy. Other tests, including cytogenetics, fluorescent in-situ hybridization and PCR analysis can allow specialists to look for genetic changes present in the biopsied tissue.
Other Tissue Sampling
Physicians can take samples from tther parts of the body to see if lymphoma has spread. They can biopsy the bone marrow in order to look for the presence of lymphoma cells. A lumbar puncture and sampling of the peritoneal fluid can look for lymphoma spread into the central nervous system and the abdomen, respectively.
