Impact of KRASG12D subtype and concurrent pathogenic mutations on advanced non-small cell lung cancer outcomes.

PURPOSE: Mutations in the Kirsten rat sarcoma viral (KRAS) oncogene constitute a significant driver of lung adenocarcinoma, present in 10-40% of patients, which exhibit heterogeneous clinical outcomes, mainly driven by concurrent genetic alterations. However, characterization of KRAS mutational subtypes and their impact on clinical outcomes in Latin America is limited. METHODS: A cohort study was conducted at the National Cancer Institute (INCan) of Mexico. Individuals with advance-staged of adenocarcinoma and KRAS mutations, detected by next-generation sequencing, having undergone at least one line of therapy were included for analysis. Clinical and pathological characteristics were retrieved from institutional database from June 2014 to March 2023. RESULTS: KRAS was identified in fifty-four (15.6%) of 346 patients, among which 50 cases were included for analysis. KRASG12D (n = 16, 32%) and KRASG12C (n = 16, 32%) represented the most prevalent subtypes. KRASG12D mutations were associated with female (p = 0.018), never smokers (p = 0.108), and concurrences with EGFR (25.0% vs. 17.6%, p = 0.124) and CDKN2A (18.8% vs. 14.7%, p = 0.157). KRASG12D patients showed a better ORR (66.6% vs. 30.0%; OR 4.66, 95% CI 1.23-17.60, p = 0.023) and on multivariate analysis was significantly associated with better PFS (HR 0.36, 95% CI 0.16-0.80; p = 0.012) and OS (HR 0.24, 95% CI 0.08-0.70; p = 0.009). CONCLUSIONS: To our knowledge, this study represents the first effort to comprehensively characterize the molecular heterogeneity of KRAS-mutant NSCLC in Latin American patients. Our data reinforce the current view that KRAS-mutated NSCLC is not a single oncogene-driven disease and emphasizes the prognostic impact of diverse molecular profiles in this genomically defined subset of NSCLC. Further validation is warranted in larger multicenter Latin American cohorts to confirm our findings.

Prevalence of pathogenic or likely pathogenic germline variants in cancer predisposition genes among selected patients with lung adenocarcinoma: The GERMLUNG study.

INTRODUCTION: Pathogenic or likely pathogenic germline variants (PGVs) in cancer predisposition genes may play a role in lung cancer (LC) susceptibility. However, determining an eligible population for genetic testing remains uncertain. This study aimed to assess the prevalence of PGVs in a selected cohort of individuals with lung adenocarcinoma. METHODS: A cross-sectional cohort study was conducted to assess the PGVs rate in lung adenocarcinoma patients with a family history of LC, young-onset presentation, history of never/light smoking, or actionable genomic alterations (AGAs). Sequencing was performed using Sophia Hereditary Cancer Solution panel F, including 144 cancer predisposition genes. Variants classified as pathogenic or likely pathogenic were included for further analysis. RESULTS: Of 201 patients, 43 (21.4 %) exhibited PGVs, among which 64.5 % were DNA damage repair genes, and 86.1 % were clinically actionable. The main PGVs were in ATM (9.3 %), TP53 (6.9 %), BRCA2 (6.9 %), and CHEK2 (6.9 %) genes. PGVs were associated with male sex (adjusted odds ratio [aOR] 2.46, 95 % CI 1.15-5.32, p = 0.021), along with a trend toward association with AGAs (aOR 6.04, 95 % CI 0.77-49.74, p = 0.094). CONCLUSIONS: In this study, a high PGVs prevalence was identified based on our selection criteria, which represents an effective strategy to identify candidates for germline genomic testing, potential screening strategies in close relatives, and personalized therapeutic modalities. Our results warrant further exploration in other populations to confirm them.

Perilesional edema diameter associated with brain metastases as a predictive factor of response to radiotherapy in non-small cell lung cancer.

Background: Different prognostic scales exist in patients with brain metastasis, particularly in lung cancer. The Graded Prognostic Assessment for lung cancer using molecular markers (Lung-molGPA index) for brain metastases is a powerful prognostic tool that effectively identifies patients at different risks. However, these scales do not include perilesional edema diameter (PED) associated with brain metastasis. Current evidence suggests that PED might compromise the delivery and efficacy of radiotherapy to treat BM. This study explored the association between radiotherapy efficacy, PED extent, and gross tumor diameter (GTD). Aim: The aim of this study was to evaluate the intracranial response (iORR), intracranial progression-free survival (iPFS), and overall survival (OS) according to the extent of PED and GT. Methods: Out of 114 patients with BM at baseline or throughout the disease, 65 were eligible for the response assessment. The GTD and PED sum were measured at BM diagnosis and after radiotherapy treatment. According to a receiver operating characteristic (ROC) curve analysis, cutoff values were set at 27 mm and 17 mm for PED and GT, respectively. Results: Minor PED was independently associated with a better iORR [78.8% vs. 50%, OR 3.71 (95% CI 1.26-10.99); p = 0.018] to brain radiotherapy. Median iPFS was significantly shorter in patients with major PED [6.9 vs. 11.8 months, HR 2.9 (95% CI 1.7-4.4); p < 0.001] independently of other prognostic variables like the Lung-molGPA and GTD. A major PED also negatively impacted the median OS [18.4 vs. 7.9 months, HR 2.1 (95% CI 1.4-3.3); p = 0.001]. Conclusion: Higher PED was associated with an increased risk of intracranial progression and a lesser probability of responding to brain radiotherapy in patients with metastatic lung cancer. We encourage prospective studies to confirm our findings.

Response rate of patients with baseline brain metastases from recently diagnosed non-small cell lung cancer receiving radiotherapy according to EGFR, ALK and KRAS mutation status.

BACKGROUND: Previous studies have identified that patients with EGFR mutations tend to have better responses to targeted therapy, as well as chemotherapy; however, the effect of genetic alterations in terms of radiotherapy (RT)-related outcomes has not been fully assessed. We studied the impact of common non-small cell lung cancer (NSCLC) genetic alterations (EGFR, ALK and KRAS) in relation to objective response rate (ORR) to RT in patients with brain metastases. METHODS: From 2009-2015, 153 patients with an available genotyping status were treated with whole-brain irradiation (WBI) before receiving systemic therapy. Primary outcome was ORR; secondary outcomes included intracranial progression-free survival (IPFS) and overall survival (OS). RESULTS: Overall, ORR was 47.1%. ORR to RT varied significantly according to molecular status: EGFR (64.5%) ALK (54.5%) KRAS (20%) and WT (35.4%) (P = 0.001). EGFR mutation was the only independently associated factor for response to WBI (RR 3.52 [95% CI 1.6-7.7]; P = 0.002). Median IPFS was 10.8 months [95% CI 8.2-13.5] overall; however, IPFS also varied significantly according to molecular status: EGFR (18.2 months), ALK (18.4 months), KRAS (6.0 months) and WT (8.7 months) (P < 0.0001). OS for EGFR, ALK, KRAS and WT patients was 36.6, 32.2, 15.5 and 22.4 months, respectively (P = 0.014). Intracranial-ORR (HR 0.4 [95% CI 0.2-0.6], P < 0.001) and mutation status (HR 0.7 [95% CI 0.6-0.9], P < 0.042) were independently associated with a higher OS. CONCLUSIONS: RT response varies as per tumor molecular status. The presence of EGFR mutations favors the organ-specific response to RT, and is associated with longer OS in patients with NSCLC and BM. KEY POINTS: This study addressed for the first time the difference in radiotherapy-related outcomes in patients with different genotypes of non-small cell lung cancer (NSCLC) before they received systemic therapy. Results show that response to radiotherapy varies as per tumor molecular status, particularly EGFR-mutated tumors, have a favorable response to radiotherapy, contrary to KRAS-mutated tumors.

Impact of KRASG12D subtype and concurrent pathogenic mutations on advanced non-small cell lung cancer outcomes / Impacto del subtipo KRASG12D y mutaciones patogénicas concurrentes en los resultados del cáncer de pulmón de células no pequeñas avanzado

Purpose: Mutations in the Kirsten rat sarcoma viral (KRAS) oncogene constitute a significant driver of lung adenocarcinoma, present in 10–40% of patients, which exhibit heterogeneous clinical outcomes, mainly driven by concurrent genetic alterations. However, characterization of KRAS mutational subtypes and their impact on clinical outcomes in Latin America is limited. Methods: A cohort study was conducted at the National Cancer Institute (INCan) of Mexico. Individuals with advance-staged of adenocarcinoma and KRAS mutations, detected by next-generation sequencing, having undergone at least one line of therapy were included for analysis. Clinical and pathological characteristics were retrieved from institutional database from June 2014 to March 2023. Results: KRAS was identified in fifty-four (15.6%) of 346 patients, among which 50 cases were included for analysis. KRASG12D (n = 16, 32%) and KRASG12C (n = 16, 32%) represented the most prevalent subtypes. KRASG12D mutations were associated with female (p = 0.018), never smokers (p = 0.108), and concurrences with EGFR (25.0% vs. 17.6%, p = 0.124) and CDKN2A (18.8% vs. 14.7%, p = 0.157). KRASG12D patients showed a better ORR (66.6% vs. 30.0%; OR 4.66, 95% CI 1.23–17.60, p = 0.023) and on multivariate analysis was significantly associated with better PFS (HR 0.36, 95% CI 0.16–0.80; p = 0.012) and OS (HR 0.24, 95% CI 0.08–0.70; p = 0.009). Conclusions: To our knowledge, this study represents the first effort to comprehensively characterize the molecular heterogeneity of KRAS-mutant NSCLC in Latin American patients. Our data reinforce the current view that KRAS-mutated NSCLC is not a single oncogene-driven disease and emphasizes the prognostic impact of diverse molecular profiles in this genomically defined subset of NSCLC. Further validation is warranted in larger multicenter Latin American cohorts to confirm our findings.(AU)

Characteristics of progression to tyrosine kinase inhibitors predict overall survival in patients with advanced non-small cell lung cancer harboring an EGFR mutation.

BACKGROUND: Non-small cell lung cancer (NSCLC) harboring EGFR-sensitizing mutations has a distinct biology and heterogeneous clinical behavior. We evaluated the characteristics to progression such as clinical patterns of progression (dramatic, gradual, and local) with the prognosis of NSCLC patients treated with tyrosine kinase inhibitors (TKIs). METHODS: We reviewed 123 advanced-NSCLC patients with an EGFR-sensitizing mutation treated with TKIs (gefitinib, erlotinib and afatinib). We assessed patients according to clinical factors and progression pattern to TKIs at three centers. RESULTS: For all patients, 58.5%, 31.7% and 9.8% harbored exon19 deletion, exon21 L858R mutation and other-sensitivity mutations, respectively. Median progression-free survival (PFS) was 8.8 months (95% CI: 7.9-9.7). Sixty percent of patients were asymptomatic. Dramatic-progression was the most frequent pattern (50.4%), followed by gradual-progression (32.5%), and local-progression (17.1%). Median overall survival (OS) was 23.1 months (95% CI: 17.4-28.9). In the univariate analysis, factors associated to a longer OS included pattern [gradual-progression (32.1), dramatic (19.5) and local (18.8 months), P=0.008], and the time to progression to TKI [>12 months (38.5), 6-12 months (19.1), <6 months (9.6), P<0.001]. Multivariate analysis showed that only time to progression to TKI was independently associated to OS and PFS. CONCLUSIONS: Factors at TKI progression associated to a longer OS can define a subset of patients who may benefit from continued TKI therapy, as well as from local-ablative therapy in progression sites, especially in patients without T790M or who lack access to third-generation TKI.

Reduction in Hepatocyte Growth Factor Serum Levels is Associated with Improved Prognosis in Advanced Lung Adenocarcinoma Patients Treated with Afatinib: a Phase II Trial.

BACKGROUND: C-met and its ligand, hepatocyte growth factor (HGF) have been associated with the resistance mechanism of EGFR-TKIs. HGF was evaluated as a clinical-marker of response in NSCLC patients treated with afatinib. METHODS: Sixty-six patients with stage IIIB/IV lung adenocarcinoma and progression to any-line chemotherapy received afatinib 40 mg/day. Mutational EGFR and HER2 status were assessed by RT-PCR. HER2 amplification was evaluated by FISH. Serum HGF content was measured by ELISA before and 2 months after the start of treatment. HGF levels were assessed with the objective response rate (ORR), progression-free-survival (PFS), and overall survival (OS). This trial was registered on ClinicalTrials.gov: NCT01542437. RESULTS: Fifty patients (75 %) were EGFR mutation positive. Response was achieved in 59 % of all patients and 78 % of EGFR mutated patients. Median PFS was 10 [95 % CI 6.8-13.1] and 14.5 months [10.9-18.9] for all and EGFR mutated patients, respectively. Median OS was 22.8 [17.5-28.1] and 32.4 months [18.3-46.6] for all and EGFR mutated patients, respectively. Patients with reduced serum HGF levels had improved ORR (75 % vs 44 %; p = 0.011), PFS (15.1 [2.9-27.3] vs 6.5 months [3.9-9.1]; p = 0.005) and OS (NR vs 14.5 months [7.8 - 21.3] p = 0.007). A reduction in serum HGF levels was an independent factor associated with longer PFS (HR 0.40; p = 0.021) and OS (HR 0.31; p = 0.006) in all and EGFR mutated patients. CONCLUSIONS: A reduction in serum HGF levels was associated with improved outcomes in patients treated with afatinib. These results suggest HGF might have a role as a mechanism of resistance to EGFR-TKIs. HGF could represent a potential therapeutic target to prevent or reverse resistance particularly in EGFR mutated patients.