Clinicopathologic and immunophenotypic study of non-Hodgkin's lymphoma in Korea

Abstract

This study sponsored by the Lymphoreticular Study Group of the Korean Society of Pathologists was carried out to provide nationwide data about the histopathologic-immunophenotypic features of malignant lymphomas in Korea. Two hundred and ninety Non-Hodgkin's lymphoma (NHL) among 312 malignant lymphomas collected from three representative areas in Korea were histologically reclassified. Two hundred and fifty three cases were immunohistochemically studied. T-cell lymphoma comprised 35.2% of NHL in this study and showed a quite comparable incidence to that of Japan and China, but it was much higher than in Western countries. A very low prevalence rate of the follicular variety (4.0%) and a higher propensity of primary extranodal involvement (60%) are additional characteristics of NHL in Korea. The most common histologic subtype of B cell lymphoma was diffuse large cell type, whereas the most common subtype of T cell lymphoma was diffuse mixed small and large cell type.

Distribution of lymphoid neoplasms in the Republic of Korea: Analysis of 5318 cases according to the World Health Organization classification

“…Our findings are in agreement with previous results, showing the relatively higher proportions of patients with overall NHL and T/NK-cell neoplasms, and the relatively lower proportions of patients with FL, CLL/SLL, and HL among Korean individuals compared with those of Western populations (Supplementary Table III) [4][5][6][7][8][9][10][11][12][13][14][15][16][17]19,21,23,37].…”

“…As for MALT lymphoma, the frequency observed in this study was similar to that of previous Korean data, and higher than the Japanese or USA data (Supplementary Table III) [4][5][6][7][8][9][10][11][12][13][14][15][16][17]19,21,23,37]. In agreement with previous findings, we found that the proportions of Korean patients with CLL/SLL and FL were low; this is in contrast to the increased rate of FL in Japan, where this subtype now accounts for 20% of all NHLs [12,22,27,45].…”

“…Among the mature T/NK-cell neoplasms, peripheral T-cell lymphoma and extranodal NK/T-cell lymphoma of nasal type exhibited similar proportions, as has been shown in other studies from East Asian countries, and these subtypes were much more common than those of Western countries (Supplementary Table III) [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]37,40]. We found that the proportion of patients with ALL/ABL (16.4% of total lymphoid neoplasms) was in agreement with the nationwide incidence ratio based on Korea National Cancer Incidence Database of the period 1999-2005 (Supplementary Table IV) [11], but was much higher than that in previous reports from Korea (3.4-5.5%) [19,21,23]. Similarly, the relative proportion of patients with plasma cell neoplasms (14.8%) in our study was significantly higher than that previously noted for Korean (1.5%) and Japanese (0.6%) individuals, but was in good agreement with the actual nationwide incidence ratio (15.2%; Supplementary Table IV) [11]; this difference is most likely due to differences in inclusion criteria of the studies.…”

“…Similarly, the relative proportion of patients with plasma cell neoplasms (14.8%) in our study was significantly higher than that previously noted for Korean (1.5%) and Japanese (0.6%) individuals, but was in good agreement with the actual nationwide incidence ratio (15.2%; Supplementary Table IV) [11]; this difference is most likely due to differences in inclusion criteria of the studies. This study included comprehensive spectrum of lymphoid neoplasms of solid and circulating phase, but previous reports from Korea analyzed mainly solid phase tumor [19,21,23]. Therefore, the present data could more appropriately reflect the subtype distribution of lymphoid neoplasms, especially as for circulating phase tumors in the Republic of Korea.…”

“…Although these data effectively characterize the subtype spectrum of lymphomas [18][19][20][21][22][23][24][26][27][28][29][30][31][32][33][34][35], most studies have excluded the majority of plasma cell neoplasms and leukemias (circulating phase). Therefore, these results may not be comparable with population-based incidence data for the entire spectrum of WHO classifications [10,42,43].…”