Screen-detected multiple primary lung cancers in the ITALUNG trial

Mario Mascalchi, Camilla E. Comin, Elena Bertelli, Lapo Sali, Cristina Maddau, Stefania Zuccherelli, Giulia Picozzi, Laura Carrozzi, Michela Grazzini, Gabriella Fontanini, Luca Voltolini, Alessandra Vella, Francesca Castiglione, Francesca Carozzi, Eugenio Paci, Maurizio Zompatori, Andrea Lopes Pegna, Fabio Falaschi, for the ITALUNG Study Research Group

Abstract

Occurrence of multiple primary lung cancers (MPLC) in individuals undergoing low-dose computed tomography (LDCT) screening has not been thoroughly addressed. We investigated MPLC in subjects recruited in the ITALUNG randomized clinical trial. Cases of cytologically/histologically proven MPLC detected at screening LDCT or follow-up CT were selected and pathologically re-evaluated according to the WHO 2015 classification. Overall 16 MPLC were diagnosed at screening LDCT (n=14, all present at baseline) or follow-up CT (n=2) in six subjects (4 in one subject, 3 in two and 2 in three subjects), representing 0.43% of the 1,406 screenees and 15.8% of the 38 subjects with at least one screen-detected primary lung cancer. MPLC included 9 adenocarcinomas in three subjects and a combination of 7 different tumour histotypes in three subjects. MPLC, mostly adenocarcinomas, are not uncommon in smokers and ex-smokers with at least one LDCT screen detected primary lung cancer.