Incidence trends for common subtypes of T-cell lymphoma in Taiwan and the United States from 2008-2020

The incidence of T-cell lymphoma (TCL) has been continually increasing in Taiwan and the United States (US) in recent years. This epidemiological study using population-based registry data aimed to determine the incidence patterns of common subtypes of TCL in Taiwan from 2008-2020 and compare them with those in the US and the Asian/Pacific Islander (API) population. Subtypes included angioimmunoblastic T-cell lymphoma (AITL); extranodal NK/T-cell lymphoma, nasal or other type (ENKTL); peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS); and anaplastic large cell lymphoma (ALCL). The total number of patients newly diagnosed with TCL during 2008-2020 was 4477, 3171, and 48,889 in Taiwan, API, and the US, respectively. Except the incidence rate of AITL in Taiwan, the incidence rates of these common TCL subtypes showed downward trends in all studied populations. There was also a significant increase in the relative frequency of AITL among TCL in Taiwan, with an annual percent change of 4.44 (p < 0.001), from 8.44% in 2002 to 20.63% in 2020. The rapid development of diagnostics may be the main factor contributing to this rise in incidence.