Dataset Information

Retrospective Comparative Analysis of KRAS G12C vs. Other KRAS Mutations in mCRC Patients Treated With First-Line Chemotherapy Doublet + Bevacizumab

ABSTRACT:

Background

KRAS mutations in metastatic colorectal cancer (mCRC) define a subset of tumors that have primary resistance to anti-EGFR-based therapy. Data concerning whether different KRAS mutations may also have a prognostic value are lacking. Furthermore, novel KRAS G12C inhibitors are currently in development. The aim of our analysis was to compare response rates in patients treated with first-line chemotherapy doublet + Bevacizumab among different KRAS variants. Secondary end-points were progression free survival (PFS) and overall survival (OS).

Methods

Patients with KRAS mutated mCRC treated with either FOLFIRI/FOLFOX/XELOX + Bevacizumab were eligible for enrollment. Patients whose tumor harbored NRAS mutations or that coexpressed also BRAF mutations were excluded from this retrospective analysis. Patients’ individual data were collected from patients’ records. Propensity score matching (nearest method, 1:2 ratio) was used to define the two different groups of patients for comparison (KRAS G12C mutated vs other KRAS variants). Eastern Cooperative Oncology Group Performance Status (ECOG PS), sex, metastatic site of involvement, synchronous vs metachronous metastatic disease, tumor sidedness, mucinous histology, primary tumor surgery, more than two lines of treatment for metastatic disease, and radical surgery of metastases were used as matching factors. Response rate (RR) was calculated by RECIST 1.1 criteria. Both progression free-survival and overall survival were calculated by Kaplan–Meier method. Categorical variables were compared by Fisher exact test for binomial variables and by chi-square test for all other instances. The level of statistical significance p was set at 0.05 for all tests.

Results

A total of 120 patients were assessed in the final analysis. Out of the 120 patients, 15 (12%) were KRAS G12C mutated. In the whole cohort of patients, 59/120 (49%) had partial response (PR), 42/120 (35%) had stable disease (SD), and 19/120 (16%) had progressive disease (PD) as the best response. In KRAS G12C patients, 4/15 (27%) had PR, 6/15 (40%) had SD, and the remaining 5/15 (33%) had PD as the best response. In patients with other KRAS mutations, 55/105 (52%) had PR, 37/105 (35%) had SD, and the remaining 13/105 (12%) had PD as the best response. The difference in RR between the two groups of patients was statistically significant (p=0.017). On the other hand, no difference in PFS (p=0.76) and OS (p=0.56) was observed. After matching procedures, the difference in response rates between KRAS G12C mutated patients vs the matched cohort of patients with other KRAS mutations remained statistically significant (p=0.016). KRAS G12C mutations were not associated with differences in sites of metastatic involvement, sex, and ECOG PS. On the other hand, synchronous vs metachronous metastatic disease (p=0.039), age > 75 years (p=0.043), and mucinous histology (p=0.008) were more frequent in G12C mutated tumors.

Conclusions

In our cohort of patients, it was observed that KRAS G12C mutations are associated with worse response rates compared to other KRAS variants when treated with standard chemotherapy doublet + Bevacizumab. On the other hand, both PFS and OS were not significantly different. Based on these findings, we believe that new treatment options focused on KRAS G12C inhibition should be tested mainly in first-line setting and in addition to standard chemotherapy doublet + Bevacizumab for mCRC patients, as they might “fill the gap” in response rates that was seen in our study.

SUBMITTER: Giampieri R

PROVIDER: S-EPMC8514824 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Bevacizumab, combined with platinum-based chemotherapy, has been widely used in the treatment of advanced-stage lung adenocarcinoma (LADC). Although KRAS (V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) mutation is the most common genetic alteration in human LADC and its role in promoting angiogenesis has been well established, its prognostic and predictive role in the above setting remains unclear. The association between KRAS exon 2 mutational status and clinicopathological variables including progression-free survival and overall survival (PFS and OS, respectively) was retrospectively analyzed in 501 Caucasian stage IIIB-IV LADC patients receiving first-line platinum-based chemotherapy (CHT) with or without bevacizumab (BEV). EGFR (epidermal growth factor receptor)-mutant cases were excluded. Of 247 BEV/CHT and 254 CHT patients, 95 (38.5%) and 75 (29.5%) had mutations in KRAS, respectively. KRAS mutation was associated with smoking (p = 0.008) and female gender (p = 0.002) in the BEV/CHT group. We found no difference in OS between patients with KRAS-mutant versus KRAS wild-type tumors in the CHT-alone group (p = 0.6771). Notably, patients with KRAS-mutant tumors demonstrated significantly shorter PFS (p = 0.0255) and OS (p = 0.0186) in response to BEV/CHT compared to KRAS wild-type patients. KRAS mutation was an independent predictor of shorter PFS (hazard ratio, 0.597; p = 0.011) and OS (hazard ratio, 0.645; p = 0.012) in the BEV/CHT group. G12D KRAS-mutant patients receiving BEV/CHT showed significantly shorter PFS (3.7 months versus 8.27 months in the G12/13x group; p = 0.0032) and OS (7.2 months versus 16.1 months in the G12/13x group; p = 0.0144). In this single-center, retrospective study, KRAS-mutant LADC patients receiving BEV/CHT treatment exhibited inferior PFS and OS compared to those with KRAS wild-type advanced LADC. G12D mutations may define a subset of KRAS-mutant LADC patients unsuitable for antiangiogenic therapy with BEV.

Project description:BackgroundDoublet platin-chemotherapy was the old standard treatment for different histology types of advanced and metastatic lung cancer (LC) and is still an option for patients who are not eligible for immune checkpoint inhibitors. However, in low- and middle-income countries, chemotherapy, either in monotherapy or in combination with platinum, is still the only accessible option in public institutions. The efficacy of different platin-based chemotherapy in patients with LC who are treatment-naïve is unknown.MethodsIn this retrospective study, we selected patients with advanced and metastatic (IIIB-IVB) non-squamous non-small cell LC (NSCLC), squamous NSCLC, and lung neuroendocrine tumours (small cell LC (SCLC), large cell neuroendocrine, and atypical carcinoid) aged beyond 18 years who received first-line chemotherapy (docetaxel, gemcitabine, etoposide, paclitaxel, pemetrexed, and vinorelbine) combined with platinum between January 1, 2013, and December 31, 2022. Within the population with non-squamous NSCLC, squamous NSCLC, and neuroendocrine tumours, progression-free survival (PFS) and overall survival (OS) were the primary assessed endpoints. Hematologic safety was the secondary endpoint.ResultsOverall, 611 patients were included. In the group of patients with non-squamous NSCLC (n = 390), there was no statistical difference between subgroups of patients who received first-line platin-chemotherapy. The median PFS was 182 (95 % confidence interval [CI], 167-208) days (hazard ratio for progression: NR [Not Reached]; p = 0.37), and the median OS was 446 (95 % CI, 405-559) days (hazard ratio for death: 1.31; 95 % CI, 0.94 - 1.82; p = 0.1). In the group of patients with squamous NSCLC (n = 149), we note the absence of statistical significance between subgroups of patients who received platin-based chemotherapy. The median PFS was 195 (95 % CI, 142-238; hazard ratio for progression: 1.21, 95 % CI, 0.29-5.02; p = 0.27), while the median OS was 428 (95 % CI, 324-940) days (hazard ratio for death: 1.76; 95 % CI, 0.93 to 3.3; p = 0.32). The absence of significance has been noticed in the neuroendocrine subgroup of patients who received first etoposide-platinum, vinorelbine-platinum, or paclitaxel-platinum (n = 72). The median PFS was 216 (95 % CI, 193-277) days; hazard ratio for progression: 1.74, 95 % CI, 0.41-7.27; p = 0.69, while the median OS was 273 (95 % CI, 241-459) days (hazard ratio for death: 2.95; 95 % CI, 0.4-21.7; p = 0.51). Grade 3-4 neutropenia grade was the predominant adverse event associated with chemotherapy in almost 11 % of patients.ConclusionMoving forward, treatment strategies must be refined for patients, with an emphasis on increasing the number of patients who can benefit from emergent approaches in order to guarantee a wider, deeper, and longer-lasting outcome.