Analysis of follicular lymphoma by dual-color fluorescence in situ hybridization

Abstract

Follicular lymphoma (FL) is divided into two groups: one with the t(14;18)(q32;q21) and the other without this translocation but with other chromosomal abnormalities including t(3q27) break. The majority of FLs in Western countries have the former chromosomal changes with characteristic clinical features and low histological grades. The goal of this study was to investigate the characteristics of Korean FLs with regard to the underlying molecular defects. Sixty-one cases of FL were evaluated from two centers in Korea by immunostaining for CD10, bcl-2, and bcl-6 proteins. Fluorescence in situ hybridization was performed to detect the t(14;18) and t(3q27) break. Cases with FL grade 3 accounted for 57% of all 61 cases. The t(14;18) was detected in 43.9% of the cases studied, and the frequency was 80, 50, 34.8, and 9.1% from grade 1 through grade 3b. The t(3q27) was detected in 16.1% of cases. Cases without a t(14;18) were mainly histological grade 3 (P < 0.001) and had a tendency to have the t(3q27) and bcl-2 amplification. The incidence of t(14;18)-positive low-grade FL was found to be lower in Korea than in Western countries. The increased frequency of t(14;18)-negative grade 3 FL attributes to the lower incidence of t(14;18) in Korean FL.

Follicular lymphoma in Taiwan: a low frequency of t(14;18), with grade 3A tumours more closely related to grade 3B than to low‐grade tumours

“…The frequency in the majority of studies in Western countries (North America and Europe) is in the range of 80–100% . Data from the Asian countries are more scarce, and the range is approximately 50–80% . Our figure of 47% (42 of 90 cases) and that of 44% (25/57) from Korea are the lowest rates ever reported for FL .…”

“…However, as there were only 13 cases in that report, this high rate may not be representative of the true incidence in Thailand. The Korean study showed the lowest rate (44%) of t(14;18) in FL, but this was biased because of a very high proportion (57%) of HG tumours . In that study, the t(14;18) rate among LG FLs was 70% (16/23 cases), which is similar to our finding of 63% (36/57), but both rates were significantly lower than that in the West.…”

“…Data from the Asian countries are more scarce, and the range is approximately 50–80% . Our figure of 47% (42 of 90 cases) and that of 44% (25/57) from Korea are the lowest rates ever reported for FL . To the best of our knowledge, there are no available data from other geographical regions.…”

“…[27][28][29][30][31][32] Our figure of 47% (42 of 90 cases) and that of 44% (25/57) from Korea are the lowest rates ever reported for FL. 28 To the best of our knowledge, there are no available data from other geographical regions.…”

New developments in the pathology of malignant lymphoma: a review of the literature published from January to April 2008

“…Since the cases of grade 3 had the least translocations, it might be that they correspond to the 3B cases in Western countries [13]. …”