Childhood lymphoma incidence patterns by ICCC-3 subtype in Mexico City metropolitan area population insured by Instituto Mexicano del Seguro Social, 1996–2010

Purpose: We reviewed the childhood lymphomas epidemiological data for the Mexico City metropolitan area (MCMA). Methods: Data analysis from children (0-14 years old) diagnosed with lymphoma during the period 1996-2010 was performed at the Mexican Childhood Cancer Registry. Histological subtype was determined according to the International Classification of Childhood Cancer 3 (ICCC–3). Age-adjusted incidence rates were calculated per 1,000,000 children/year by age, gender, and ICCC-3 subtype; trends, by average annual percent change (AAPC). Results: A total of 328 lymphoma cases included in the study had an incidence rate of 11.8, showing a decreasing trend [AAPC: -3.5; CI95% (−5.9, −1.0)], primarily due to non-Hodgkin lymphomas (NHL) and Hodgkin lymphoma (HL) mixed cellularity subtype. NHL had the major incidence (5.8), with the precursor cell subtype being the most frequent (38.3 %). Nodular sclerosis was the most frequent HL subtype. The incidence of Burkitt lymphoma was low (1.3). During the study period, there was an important reduction in the not-otherwise-specified subtype of NHL, which translated into a relative increase in the IIb3 subtype [AAPC: 7.3 (1.2, 13.8)]. Low incidences of NHL and of HL and NHL were found for