Tests that examine the body and lymph system are used to help detect (find) and diagnose adult non-Hodgkin lymphoma. The following tests and procedures may be used:         -   Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patients health habits and past illnesses and treatments will also be taken.    -   Flow cytometry : A laboratory test that measures the number of cells in a sample, the percentage of live cells in a sample, and certain characteristics of cells, such as size, shape, and the presence of tumor markers on the cell surface. The cells are stained with a light-sensitive dye, placed in a fluid, and passed in a stream before a laser or other type of light. The measurements are based on how the light-sensitive dye reacts to the light. This test is used to diagnose lymphoplasmacytic lymphoma.    -   Bone marrow aspiration and biopsy : The removal of bone marrow and a small piece of bone by inserting a needle into the hipbone or breastbone. A pathologist views the bone marrow and bone under a microscope to look for signs of cancer.    -   Lymph node biopsy: The removal of all or part of a lymph node. A pathologist views the tissue under a microscope to look for cancer cells. One of the following types of biopsies may be done:                -  Excisional biopsy : The removal of an entire lymph node.       -  Incisional biopsy : The removal of part of a lymph node.      -  Core biopsy : The removal of part of a lymph node using a wide needle.       -  Fine-needle aspiration (FNA) biopsy: The removal of tissue or fluid using a thin needle.      -  Laparoscopy : A surgical procedure to look at the organs inside the abdomen to check for signs of disease. Small incisions (cuts) are made in the wall of the abdomen and a laparoscope (a thin, lighted tube) is inserted into one of the incisions. Other instruments may be inserted through the same or other incisions to take tissue samples to be checked under a microscope for signs of disease.      -  Laparotomy : A surgical procedure in which an incision (cut) is made in the wall of the abdomen to check the inside of the abdomen for signs of disease. Tissue samples are taken and checked under a microscope for signs of disease.                 If cancer is found, the following tests may be done to study the cancer cells:          -   Immunohistochemistry : A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between different types of cancer.    -   Cytogenetic analysis : A laboratory test in which cells in a sample of tissue are viewed under a microscope to look for certain changes in the chromosomes.    -   FISH (fluorescence in situ hybridization): A laboratory test used to look at genes or chromosomes in cells and tissues. Pieces of DNA that contain a fluorescent dye are made in the laboratory and added to cells or tissues on a glass slide. When these pieces of DNA attach to certain genes or areas of chromosomes on the slide, they light up when viewed under a microscope with a special light. This type of test is used to look for certain genetic markers.    -   Immunophenotyping : A process used to identify cells, based on the types of antigens or markers on the surface of the cell. This process is used to diagnose specific types of leukemia and lymphoma by comparing the cancer cells to normal cells of the immune system.        Other tests and procedures may be done depending on the signs and symptoms seen and where the cancer forms in the body.