Analysis of genomic alternations in epidermal growth factor receptor (EGFR)-T790M-mutated non-small cell lung cancer (NSCLC) patients with acquired resistance to osimertinib therapy.

BACKGROUND AND OBJECTIVES: Genomic alterations after resistance to osimertinib therapy in advanced T790M-mutated non-small cell lung cancer (NSCLC) are complex and poorly understood. In this study, we aimed to detect these genomic alternations via comprehensive next-generation sequencing (NGS) of tissue and liquid biopsies. PATIENTS AND METHODS: From September 2020 to June 2021, 31 stage IIIB/IV T790M-mutated NSCLC patients who exhibited progressive disease after osimertinib therapy and provided written informed consent were recruited. Liquid and tissue biopsy samples for NGS testing were collected from 31 and 18 patients, respectively. Eighteen study patients had paired NGS data from tissue and liquid biopsies. RESULTS: With respect to the T790M mutation status, the preservation and loss rates were 33% and 67%, respectively, in both liquid and tissue biopsy samples. Five patients (16.1%) had the C797S mutation (4 liquid samples and 1 tissue sample). Two (6.5%) had MET mutations, 3 (9.7%) had BRAF-V600E mutations, and 1 (3.2%) had a KRAS-G12C mutation. Among the 18 patients who underwent tissue rebiopsies, those with preserved T790M mutation had significantly longer progression-free survival (PFS) with osimertinib therapy than those with T790M mutation loss (10.8 vs. 5.0 months, P = 0.045). Among all patients, those with T790M mutation loss in liquid biopsy samples had longer PFS after osimertinib therapy (10.8 vs. 7.5 months, P = 0.209) and postprogression survival (17.7 vs. 9.6 months, P = 0.132) than those with preserved T790M mutation based on liquid biopsies. CONCLUSIONS: NGS using either tissue or liquid biopsy samples from advanced T790M-mutated NSCLC patients with acquired resistance to osimertinib therapy can detect various genomic alternations. Future studies focusing on subsequent tailored therapies on the basis of NGS results are warranted.

EGFR-mutated lung cancer as a secondary neoplasm in a patient with Li-Fraumeni syndrome: case report.

Background: Li-Fraumeni syndrome (LFS) is a rare hereditary disorder caused by mutations in the tumor protein p53 (TP53). It causes a predisposition for the development of multiple malignancies, primarily including breast cancers, sarcomas, and central nervous system tumors. There are a few cases reported in the literature of patients with LFS presenting with an epidermal growth factor receptor (EGFR) mutated lung cancer. Still, it has been suggested that there may be an association between the TP53 pathogenic variant and lung cancer with EGFR mutation in somatic cells. Case Description: A 47-year-old non-smoker woman with LFS with a history of multiple tumors, including bilateral breast cancer, pecoma, and sarcoma. In one of her computed tomography, a lesion in the lingula of the lung was detected. It was biopsied, which diagnosed lung adenocarcinoma, and genetic studies detected an EGFR exon 19 deletion. She was treated with a left inferior lobectomy, followed by pemetrexed and cisplatin. Conclusions: The association between TP53 and lung cancer with EGFR mutation has been suggested in case reports. Studies in lung cancer cell lines have shown a link between TP53 mutation and EGFR overexpression. Nonetheless, as more cases are reported, further research is needed to comprehend the interrelation between these two pathologies and the risk posed by LFS to the emergence of EGFR-mutated lung cancer.

Which Tyrosine Kinase Inhibitor Must We Apply Before? A Case Report of Crizotinib-resistant Patient with Concomitant EGFR and EML4-ALK Gene Mutations

ABSTRACT The concomitant epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) translocations in lung adenocancers are very rare scenarios. Until now, 42 cases described in the literature have all been treated by different drugs. There is no overall consensus regarding the treatment for this adenocarcinoma subgroup. We report here a case of lung adenocarcinoma with concomitant EGFR mutation in exon 21 (L858R) and ALK rearrangement in primary tumour, EGFR mutation in exon 21 (L858R) and no ALK rearrangement in its synchronous metastasis. We treated this patient with crizotinib as the second-line therapy (after the first line docetaxel-cisplatin chemotherapy), but no response was obtained. The therapeutic choice for the lung adenocancer patients with concomitant EGFR mutation and ALK rearrangement is unclear. Examination of c-ros oncogene 1 mutation can be used as an indicator in the prediction of the crizotinib treatment success. The ALK mutation may not responsible for the resistance to EGFR-tyrosine kinase inhibitors (TKI), and EGFR-TKI can be initiated to EGFR and ALK dual mutant patients as the first treatment.

Síndrome de Loeys-Dietz, una mutación en el gen TGFBR2, primer reporte en el suroccidente colombiano / Loeys-Dietz syndrome, a mutation in TGFBR2 gene, first report in the colombian suroccident

Resumen: el síndrome de Loeys-Dietz es una rara enfermedad genética, autosómica dominante, con hábito marfanoide, que pertenece a un subconjunto de enfermedades del tejido conectivo con afectación esquelética, ocular y cardiovascular, principalmente. El desarrollo de aneurismas es característico en esta patología. El síndrome de Loeys-Dietz es causado por mutaciones en los genes TGFBR1, TGFBR2, TGFB2, TGFB3 Y SMAD3. En este manuscrito se describe el caso clínico de un paciente masculino, de 22 meses de vida, con una dilatación importante de la raíz aórtica y arco aórtico elongado cuya prueba molecular confirma el diagnóstico de síndrome de Loeys-Dietz, asociado a una mutación en el gen TGFBR2. Este corresponde al primer caso reportado en el suroccidente colombiano. (AU)

Abstract: Loeys-Dietz syndrome is a rare, autosomal dominant genetic disease, with marfanoid habit, which belongs to a subset of diseases of the connective tissue with mainly skeletal, ocular, and cardiovascular involvement. Aneurysms development is characteristic in this pathology. Loeys-Dietz syndrome is caused by mutations in TGFBR1, TGFBR2, TGFB2, TGFB3 and SMAD3 genes. In this manuscript is presented the clinical case of a 22-month-old male patient with significant dilatation of the aortic root and elongated aortic arch is described. The molecular test confirms the diagnosis of Loeys-Dietz syndrome associated with a mutation in the TGFBR2 gene. This corresponds to the first case reported in the southwestern Colombian. (AU)