Ion AmpliSeq Cancer Panel detected 9 potentially actionable variants in 29 adenocarcinomas that were wild type by the 8-gene panel testing (9 of 29, 31.0%) in the following genes: ERBB2 (3 of 29, 10.3%), STK11 (2 of 29, 6.8%), PTEN (2 of 29, 6.8%), FBXW7 (1 of 29, 3.4%), and BRAF G469A (1 of 29, 3.4%).
The median age was 60.1 ± 14.5 (standard deviation) years; 89% (n = 106/119) had performance status 0/1 at diagnosis; 79% (n = 103/130) were non- or former smokers; 93% (n = 120/129) had adenocarcinomas and 74%(n = 97)/19%(n = 25)/7%(n = 10) had disease stages IV/III/I-II at diagnosis, respectively; co-mutations included EGFR (n = 2), BRAF (n = 2), KRAS (n = 1), and HER2 (n = 1).
HER2S310Y single site substitution was discovered in recent years and afatinib efficacy for adenocarcinoma patients harboring S310Y mutation has not been reported.
Mutations in erb-b2 receptor tyrosine kinase 2 (HER2) oncogene are observed in approximately 3% of lung adenocarcinomas or mixed tumors with adenocarcinoma component.
Target therapies against echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion protein or a mutated ERBB2 (v-ERB-B avian erythroblastic leukemia viral oncogene homologue 2) present in approximately 5% and approximately 3% of the Japanese patients with adenocarcinomas, respectively, are currently under development.
Amplification and/or overexpression of the erbB-2 gene have been demonstrated in 20-30% of adenocarcinomas of the breast, ovary, lung, and stomach and are associated with aggressive clinical course and poor prognosis.
Trastuzumab has been confirmed as an additional useful therapeutic standard option for patients with HER2-positive advanced gastric cancers, and also in aggressive variants of adenocarcinomas such as HAS.
In particular, 3 of 4 adenocarcinomas with EGFR mutations (all L858R point mutations in women, never or former smokers) had a concomitant and identical mutation in AAH, and 2 of 4 adenocarcinomas with K-ras mutations (both at codon 12 in women, a never and a current smoker) showed the same mutation in concomitant AAH.All cases were wild-type for HER2.
In this study, to explore the possibility that ERBB2 mutation is involved in the metastasis mechanism, we analyzed the kinase domain of ERBB2 for the detection of somatic mutations in 58 gastric adenocarcinomas with lymph node metastasis.
Increased copy number of the ERBB2 (1 of 22), GATA4 (1 of 22), KRAS (2 of 22), C-MYC (1 of 22), CCNE1 (2 of 22), and CCND1 (2 of 22) genes was also observed in one or more Barrett's adenocarcinomas with HGD.
HER2 mutations were detected in 29 of 572(5.1%) specimens from a selected population of EGFR/KRAS/BRAF/ALK/ROS1 negative patients.All of them are adenocarcinomas.
The ERBB2 mutation rate was significantly higher in adenocarcinoma (4.52%, 7/155), adenosquamous carcinoma (7.59%, 6/79) and neuroendocrine carcinoma (10.34%, 3/29) than that in squamous carcinoma (2.14%, 16/749) (P=0.004, Fisher exact test).
Mutational analysis of the HER2 gene in lung tumors from Caucasian patients: mutations are mainly present in adenocarcinomas with bronchioloalveolar features.
In particular, 3 of 4 adenocarcinomas with EGFR mutations (all L858R point mutations in women, never or former smokers) had a concomitant and identical mutation in AAH, and 2 of 4 adenocarcinomas with K-ras mutations (both at codon 12 in women, a never and a current smoker) showed the same mutation in concomitant AAH.All cases were wild-type for HER2.