Background: Breast implant–associated anaplastic large cell lymphoma (BIA ALCL) is a rare indolent yet lethal disease. Recently the WHO accepted it as an individual new entity. Since then national and international registries have attempted to collect epidemiological data, but incidence rates vary strongly. The aim of this article is to provide an update on the status of the national BIA-ALCL registries and identify pitfalls alongside the current collection and diagnostic algorhythm.

Methods: A systematic review of the literature was performed and epidemiological data from national registries were compared. Furthermore a case report of a false positive diagnosis was added and the pitfalls alongside the diagnostic algorhythm was worked out.

Results: The comparison of national registries revealed significant differences in the collected data. Mean start of the registries was 2014, median 2015. Reporting of BIA-ALCL cases is mandatory except in two countries. Capture rates vary between 0-100%. Incidence rates range from 0.0 up to 8.9 per million implant years. The number of deaths does not correlate with the number of implants or the total population. The very same strains of CD30 can be interpreted differently.

Conclusion: Comparing epidemiologic data revealed significant differences among national registries. In particular, non-published sales data of breast implants and non-mandatory recording of the disease lead to an overall underreporting of cases. Therefore, the incidence rates still cannot be compared uniformly. Furthermore the definition of CD30 straining intensity should be standardized and adjusted in the guidelines.