Upward trend in follicular lymphoma among the Korean population: 10-year experience at a large tertiary institution

Abstract

Background: Follicular lymphoma (FL) is the second most common non-Hodgkin lymphoma (NHL) in Western countries. However, it is relatively rare in Asia. This study examined epidemiologic characteristics of FL in South Korea, with an emphasis on recent trends of increase in cases. Methods: We retrospectively examined 239 cases of newly diagnosed FL at a large tertiary institution in Korea (Asan Medical Center, Seoul, Republic of Korea) between 2008 and 2017. Age-adjusted incidence rates and clinicopathological variables were analyzed, and joinpoint regression analysis was used to identify the changes. Results: The age-adjusted incidence of FL significantly increased during the study period (p = .034), and the ratio of (relative incidence) patients with FL to patients with NHL increased from 4.28% to 9.35% in the same period. Over the 10-year study assessment duration, the proportion of patients with stage III/IV FL (p = .035) and expression of BCL2 (p = .022) or BCL6 (p = .039) significantly increased. From 2013-2017, the proportion of patients with highrisk Follicular Lymphoma International Prognostic Index (FLIPI) score increased (21.5% to 28.7%), whereas that of low-risk FLIPI decreased (55.4% to 38.6%), although those results were not statistically significant (p = .066). Conclusions: We found an increasing incidence of FL, with a disproportionate increase in the incidence of high-stage disease and recent changes in the clinicopathologic features of the Korean patient population.

Incidence, clinicopathological features and genetics of in‐situ follicular neoplasia: a comprehensive screening study in a Japanese cohort

“…For example, the age‐matched population‐based incidence of FL in Japan is high but remains significantly lower than that of western countries, 11 possibly due to the lower incidence of erroneous IGH translocation resulting in t(14;18). A similar trend has been reported in the Korean population 12 . Supporting this difference in FL incidences between Japan and western countries, an earlier study reported that the prevalence of t(14;18)‐positive FL cells in Japanese individuals is lower than that in Germans 13 .…”

“…A similar trend has been reported in the Korean population. 12 Supporting this difference in FL incidences between Japan and western countries, an earlier study reported that the prevalence of t(14;18)-positive FL cells in Japanese individuals is lower than that in Germans. 13 However, the incidence of isolated pure ISFN has not been investigated in the Japanese population.…”

Incidence Trend of Follicular Lymphoma in Taiwan Compared to Japan and Korea, 2001–2019

“…The literature has listed possible risk factors for follicular lymphoma (FL): a family history of NHL (1.99-fold increased risk of FL), hepatitis C virus (a 2.73-fold increased risk of FL), select autoimmune diseases, allergy/atopy, and alcohol consumption [ 8 , 9 ]. The incidence of FL has shown a rising trend in some areas, such as Canada, Poland, Japan, South Korea, and Taiwan; however, the reasons for this remain unknown [ 2 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ].…”

“…Only a few studies have investigated the incidence of FL in Asia owing to its relative rarity in Asia compared with western countries [ 7 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. In Singapore, the time trend in the incidence of NHL among men and women increased in 1998–2012, but the incidence of FL did not significantly increase [ 19 ].…”

“…Su et al demonstrated that the incidence of FL in Taiwan had an increasing trend and varied among the other ethnic groups in the United States between 2008 and 2017 [ 16 ]. The incidence in Japan from 1993 to 2014 and in the Republic of Korea from 1999 to 2015 also showed an upward trend [ 2 , 12 , 13 , 14 ]. In Sweden, the prevalence of FL increased in 2004–2016, but the incidence remained unchanged [ 1 ].…”