• Diagnose B-cell malignancies

• Determine leukemia and lymphoma lineage

• Detect minimal residual disease or recurrent disease

The evaluation of lymph nodes, bone marrow, and other tissues for the presence of lymphoma usually involves a multiparameter approach. The obligatory first step when evaluating a tissue for suspected lymphoma is to examine the tissue microscopically for morphology. In many cases, morphologic examination is sufficient to establish a diagnosis of malignant lymphoma. There is, however, a significant proportion of cases in which additional studies are needed in order to establish a definitive diagnosis. Those additional studies include immunoperoxidase staining of the tissue sections, flow cytometric evaluation of fresh cells from the specimen, and molecular analysis. Molecular analysis includes such modalities as cytogenetics (including FISH) and polymerase chain reaction (PCR). All of these special studies are intended to provide some evidence that can help to distinguish between benign lymphadenopathy and malignant lymphoma. In addition, the special tests can sometimes help to establish both the lineage and the presence of prognostically significant subtypes of malignant lymphoma.

14868X: B-Cell Gene Rearrangement, Qualitative PCR, Cell-Based

116119(X): B-Cell Gene Rearrangement, Qualitative PCR, Plasma-Based, Leumeta^®

Following extraction from cells (14868X) or plasma [16119(X)], DNA is amplified by PCR, utilizing 3 primer sets (FRII, FRIII, and FR3/CDR3) targeting the variable and joining regions of the immunoglobulin heavy chain gene. The amplification products are analyzed by capillary electrophoresis. Results are reported as negative or positive for the presence of a clonal B-cell expansion.

Positive results are highly suggestive of malignancy; however, a positive result should not be used as the sole criterion for diagnosis. Both positive and negative results should be interpreted in the context of all clinical and laboratory findings. Up to 20% of B-cell neoplasms can yield a false-negative result in these assays.