PCR ANALYSIS OF IGH AND BCL2 GENE REARRANGEMENT IN THE DIAGNOSIS OF FOLLICULAR LYMPHOMA IN LYMPH-NODE FINE-NEEDLE ASPIRATION - A CRITICAL-APPRAISAL

In order to improve the cytomorphologic diagnosis of malignant lymphom a on lymph node fine-needle aspiration (FNA), and to make a confident discrimination between low-grade follicular non-Hodgkin's lymphoma (NH L) and lymphoid hyperplasia, polymerase chain reaction (PCR) analysis was performed of the Ig CDR3 region and BCL2 breakpoint region in 25 n onselected cases of malignant lymphoma (17 NHL and 8 Hodgkin's disease [HD]) with histologic control, and 22 cases of lymph nodal hyperplasi a with histologic and/or clinical control. Among lymphomas, IgH monocl onality was detected in 7 (77%) of 9 NHLs and BCL2 rearrangement in 3 (17.6%) of 17 NHLs, all of which were follicular centroblastic-centroc ytic (FCBCC). Three BCL2/JH negative FCBCC cases were monoclonal for C DR3. Neither IgH monoclonality nor BCL2 rearrangement were found in HD . Among cytologically diagnosed lymphoid hyperplasias, one IgH polyclo nal case was considered false-negative, being histologically diagnosed as lymphoplasmacytic NHL on the subsequent excisional biopsy. Another 4 cases (2 BCL2 rearranged and 2 monoclonal for IgH) were considered false-positive on the basis of histologic features or clinical control . These data indicate that the combined PCR analysis of IgH and BCL2 r earrangements can confirm a cytologic diagnosis of lymphoma in FNAs wh ile, due to the occurrence of both false-positive and false-negative r esults, it is of limited value in the distinction between follicular l ymphoma and lymphoid hyperplasia without morphologic or clinical suppo rt.