Microsatellite Instability Is Rare in the Admixed Brazilian Population of Non-Small Cell Lung Cancer: A Cohort of 526 Cases

• Published in: Pathobiology (Basel) Vol. 89; no. 2; pp. 101 - 106
• Main Authors: De Marchi, Pedro, Berardinelli, Gustavo Noriz, Cavagna, Rodrigo de Oliveira, Pinto, Icaro Alves, da Silva, Flavio Augusto Ferreira, Duval da Silva, Vinicius, Santana, Iara Viana Vidigal, da Silva, Eduardo Caetano Albino, Ferro Leal, Leticia, Reis, Rui Manuel
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland 2022
• Subjects: Adenocarcinoma of Lung; Animals; Brazil; Carcinoma, Non-Small-Cell Lung - genetics; Carcinoma, Non-Small-Cell Lung - pathology; Colorectal Neoplasms - pathology; Female; Humans; Lung Neoplasms - genetics; Lung Neoplasms - pathology; Mice; Microsatellite Instability; Mutation; Proto-Oncogene Proteins p21(ras) - genetics; Research Article; Brazil; Brazil; Microsatellite instability; Immunotherapy; Non-small cell lung cancer
• ISSN: 1015-2008; 1423-0291
• DOI: 10.1159/000520023

Background: Microsatellite instability (MSI) in non-small cell lung cancer (NSCLC) is uncommon; however, most studies refer to European and Asian populations. There are currently no data on MSI frequency in highly admixed populations, such as the one represented by Brazilian NSCLC patients. Aim: This study aimed to evaluate the frequency of MSI in Brazilian NSCLC patients. Methods: We evaluated 526 patients diagnosed with NSCLC at the Barretos Cancer Hospital (Brazil). The molecular MSI evaluation was performed using a hexa-plex marker panel by polymerase chain reaction followed by fragment analysis. The mutation profile of MSI-positive cases was performed using next-generation sequencing. Results: Only 1 patient was MSI positive (0.19%). This patient was a female, white, and active smoker, and she was diagnosed with clinical stage IV lung adenocarcinoma at 75 years old. The molecular profile exhibited 4 Tumor Protein p53 (TP53) mutations and the absence of actionable mutations in the Epidermal Growth Factor Receptor (EGFR), Kirsten Rat Sarcoma Viral Oncogene Homolog (KRAS), or V-Raf Murine Sarcoma Viral Oncogene Homolog B1 (BRAF) genes. Conclusions: The frequency of MSI in Brazilian NSCLC patients is equally rare, a finding that is consistent with the current literature based on other populations such as Europeans, North Americans, and Asians.