Multifocal epithelial hyperplasia: Clinical features, diagnosis and management challenges

Table 3 Summary of the studies¹

Continent	Number of countries	Total patients (approx.)	Year range of reports
North America	3 (Canada, United States, Mexico)	Approximately 1760 (Canada: Survey of 1591 individuals, with 137-202 cases diagnosed with MEH + 169 Mexican and United States cases)	1965-2023
Central and South America	10 (Bolivia, Brazil, Colombia, El Salvador, Guatemala, Paraguay, Peru, Venezuela, Surinam)	Approximately 1757 (includes 1465 in Peru, 110 from Guatemala, 79 from Venezuela	1956-2015
Europe	9 (Germany, Greece, Italy, Lithuania, Netherlands, Poland, Spain, Sweden, United Kingdom)	Approximately 28 (mostly isolated case reports and small series)	1970s-2015
Africa	5 (Ghana, Kenya, Nigeria, South Africa, Sudan)	Approximately 156 (includes 143 in South Africa longitudinal study + small series elsewhere)	1964-2000s
Asia	1 (China)	4 (cases reported in literature review + current case)	2000s-2010s
Middle East	4 (Afghanistan, Iran, Israel, Turkey)	Approximately 22 (Turkey family clusters + Israel family + Iran/Afghan series)	1973-2010s
Arctic (Greenland)	1 (Greenland)	89 (epidemiological study of 460 examined)	1970
Total	31 countries	Approximately 3816 patients	1956-2023

¹The highest case numbers come from Peru (1465), Canada (approximately 137-202 cases, extrapolated from a survey of 1591 individuals), and South Africa (143). Many countries in Europe and the Middle East have only 1-3 cases. The full-time range extends from Estrada's first report in Colombia (1956) to the outbreak studied in Mexico (Aguilar-Jiménez, 2023).

MEH: Multifocal epithelial hyperplasia.