Diagnostic and prognostic utility of t(14;18) in follicular lymphoma.

BACKGROUND

Follicular lymphoma (FL) is one of the most common non-Hodgkin's lymphomas of B cells, being closely associated with a t(14;18) translocation. Detection of t(14;18), which is present in 70-95% of FL, might aid in FL diagnosis.

OBJECTIVE

To compare the efficacy of routine polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) techniques in detecting t(14;18) in paraffin-embedded tissue samples of FL patients at different stages. Combined with other immunophenotypic biological determinants, detection of t(14;18) might help to determine patients at increased risk according to the FL International Prognostic Index (FLIPI) and therefore facilitate appropriate treatment.

DESIGN AND METHODS

This study was mainly based on a retrospective examination of formalin-fixed, paraffin-embedded lymph nodes. We selected fixed tissue samples of 21 FL patients treated at the National Cancer Institute Center in the period from 2000 to 2001.

RESULTS

FISH techniques could detect 14 of 18 FL cases with a sensitivity of 77.8%, while the PCR technique could detect only 11 of 18 FL cases with a sensitivity of 61.1%, resulting in a statistically significant difference between both techniques (p = 0.004). According to the FLIPI index, 9 of the 18 FL patients were categorized into the high-risk group (50%), 5 in the intermediated-risk group (27.8%) and 4 in the low-risk group (22.2%).

CONCLUSION

The sensitivity of FISH is superior to that of PCR in the detection of the t(14;18) translocation in paraffin-embedded tissue samples. There is a statistically significant correlation between both CD10 and FISH with FLIPI.