Molecular Epidemiology of ALK Rearrangements in Advanced Lung Adenocarcinoma in Latin America

Objective: Latin American countries are heterogeneous in terms of lung cancer incidence and exposure to potential carcinogens. We evaluated the frequency and clinical characteristics of ALK rearrangements (ALKr) in Latin America. Methods: A total of 5,130 lung cancer patients from 10 Latin American countries were screened for inclusion. ALKr detection was performed by fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) to assess method variability. Demographic and clinicopathologic characteristics were analyzed. Results: Among the 5,130 patients screened, 8.4% (n = 433) had nonevaluable FISH tests. Evaluable FISH analyses revealed positive ALKr in 6.8% (320/4,697) of the study population, which included patients from 9 countries. ALKr distribution for each country was: Mexico 7.6% (79/1,034), Colombia 4.1% (10/242), Argentina 6.0% (153/2,534), Costa Rica 9.5% (13/137), Panama 4.4% (5/114), Uruguay 5.4% (2/37), Chile 8.6% (16/185), Venezuela 8.9% (13/146), and Peru 10.8% (29/268). RT-PCR showed high positive (83.6%) and negative (99.7%) predictive values when compared to the gold standard FISH. In contrast, IHC only showed a high negative predictive value (94.6%). Conclusions: Although there is a clear country and continental variability in terms of ALKr frequency, this difference is not significant and the overall incidence of ALKr in Latin America does not differ from the rest of the world.Fil: Arrieta, Oscar. Instituto Nacional de Cancerologia; MéxicoFil: Cardona, Andrés F.. Institute Of Oncology; ColombiaFil: Bramuglia, Guillermo. Foundation For Clinical And Applied Cancer Research; ColombiaFil: Cruz Rico, Graciela. Instituto Nacional de Cancerologia; MéxicoFil: Corrales, Luis. Hospital San Juan de Dios; Costa RicaFil: Martín, Claudio. Instituto Alexander Fleming.; ArgentinaFil: Imaz Olguín, Victoria. Hospital ABC; Costa RicaFil: Castillo, Omar. National Institute of Cancer; PanamáFil: Cuello, Mauricio. Universidad de la República; UruguayFil: Rojas Bilbao, Érica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Casas, Gabriel. Hospital Aleman; ArgentinaFil: Fernández, Cristina. Hospital Clínico de la Universidad de Chile; ChileFil: Arén Frontera, Osvaldo. Hospital Clínico de la Universidad de Chile; ChileFil: Denninghoff, Valeria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Recondo, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Avilés Salas, Alejandro. Instituto Nacional de Cancerología; MéxicoFil: Mas Lopez, Luis Alberto. Instituto Nacional de Enfermedades Neoplásicas; PerúFil: Oblitas, George. Instituto Oncologico “Dr. Luis Razetti”; VenezuelaFil: Rojas, Leonardo. Hospital Universitario San Ignacio; ColombiaFil: Piottante, Antonio. Clínica las Condes; ChileFil: Jiménez García, Ernesto. No especifíca;Fil: Sánchez-Sosa, Sergio. Hospital Ángeles de Puebla; MéxicoFil: Sáenz Frias, Julia. Instituto Mexicano del Seguro Social; MéxicoFil: Lupera, Hernán. Hospital Metropolitano; EcuadorFil: Ramírez Tirado, Laura Alejandra. Instituto Nacional de Cancerología; MéxicoFil: Vargas, Carlos. Institute of Oncology; ColombiaFil: Carranza, Hernán. Institute of Oncology; ColombiaFil: Astudillo, Horacio. No especifíca;Fil: Wills, Laura Beatriz. No especifíca;Fil: Pichelbaur, Ernestina. Universidad de Buenos Aires; ArgentinaFil: Raez, Luis E.. Memorial Cancer Institute; Estados Unido