Predictors of outcome for patients with lung adenocarcinoma carrying the epidermal growth factor receptor mutation receiving 1st-line tyrosine kinase inhibitors: Sensitivity and meta-regression analysis of randomized trials

Clinical outcomes of chemotherapy in cancer patients with different ethnicities

BACKGROUND

Choosing the most effective chemotherapeutic agent with safest side effect profile is a common challenge in cancer treatment. Although there are standardized chemotherapy protocols in place, protocol changes made after extensive clinical trials demonstrate significant improvement in the efficacy and tolerability of certain drugs. The pharmacokinetics, pharmacodynamics, and tolerance of anti-cancer medications are all highly individualized. A driving force behind these differences lies within a person's genetic makeup.

RECENT FINDINGS

Pharmacogenomics, the study of how an individual's genes impact the processing and action of a drug, can optimize drug responsiveness and reduce toxicities by creating a customized medication regimen. However, these differences are rarely considered in the initial determination of standardized chemotherapeutic protocols and treatment algorithms. Because pharmacoethnicity is influenced by both genetic and nongenetic variables, clinical data highlighting disparities in the frequency of polymorphisms between different ethnicities is steadily growing.  Recent data suggests that ethnic variations in the expression of allelic variants may result in different pharmacokinetic properties of the anti-cancer medication. In this article, the clinical outcomes of various chemotherapy classes in patients of different ethnicities were reviewed.

CONCLUSION

Genetic and nongenetic variables contribute to the interindividual variability in response to chemotherapeutic drugs. Considering pharmacoethnicity in the initial determination of standard chemotherapeutic protocols and treatment algorithms can lead to better clinical outcomes of patients of different ethnicities.

Predictors of Outcomes in Patients with EGFR-Mutated Non-Small Cell Lung Cancer Receiving EGFR Tyrosine Kinase Inhibitors: A Systematic Review and Meta-Analysis

Some commonly available patient or disease characteristics may be associated with progression-free survival (PFS) and overall survival (OS) in EGFR-mutant non-small cell lung cancer (NSCLC) patients receiving EGFR-TKIs (epidermal growth factor receptor - tyrosine kinase inhibitors). We performed a systematic review and meta-analysis of randomized control trials (RCTs) to explore differences in outcomes associated with EGFR-TKIs among subgroups of EGFR-mutant NSCLC patients. Pooled HRs for progression or death (PFS-HRs) and pooled HRs for death (OS-HRs) were compared among sub-groups defined according to baseline clinical and demographic variables as well as type of EGFR mutation. In the entire assessable population of 4465 EGFR-mutant NSCLC patients, significant interactions with PFS were found for gender (males vs. females; pooled ratio of the PFS-HRs = 1.2; 95% CI 1.12-1.56), smoking history (smokers vs. non-smokers; pooled ratio of the PFS-HRs = 1.26; 95% CI 1.05-1.51), and type of EGFR mutation (patients with exon 21 L858R mutation vs. exon 19 deletion; pooled ratio of the PFS-HRs = 1.39; 95% CI 1.18-1.63). Male patients, smokers and patients with EGFR exon 21 L858R mutation may derive less benefit from EGFR-TKIs compared to female patients, non-smokers and patients with EGFR exon 19 deletion.

PD-L1 for selecting non-small-cell lung cancer patients for first-line immuno-chemotherapy combination: a systematic review and meta-analysis

Aim: With the final aim to explore the first-line treatment options for non-small-cell lung cancer (NSCLC) patients, we performed a systematic review and literature-based meta-analysis of available clinical trials exploring immunotherapy in combination versus standard histology-based chemotherapy. Materials & methods: We evaluated interactions according to type of treatment-add-on strategy: immunotherapy in combination versus standard chemotherapy-based regimens. Hazard ratio (HR) for overall survival (OS) and progression-free survival (PFS) were extracted and cumulated. Results: Seven trials (4278 patients) were included. The addition of immunotherapy to standard chemotherapy-based regimens significantly increased OS (HR 0.74; p = 0.001) and PFS (HR 0.61; p < 0.0001) compared with standard-of-care in NSCLC patients in first-line setting. Conclusion: Immunotherapy-based regimens constantly improved OS and PFS compared with chemotherapy in first-line treatment of nononcogene-addicted NSCLC.

Avoiding chemotherapy for advanced nononcogene addicted NSCLC overexpressing PD-L1: Rule or option?

Patients with nonsmall-cell lung cancers expressing high levels of PD-L1 present a therapeutic dilemma for clinicians who have to choose between pembrolizumab as a single agent or in combination with chemotherapy. In order to help them as they ponder over this decision we performed a meta-analysis using the data available from randomized clinical trials that enrolled patients with untreated advanced nonsmall-cell lung cancers with PD-L1 expression level ≥50%. We evaluated interactions according to type of treatment-add-on strategy: pembrolizumab plus chemotherapy versus chemotherapy or head-to-head strategy: pembrolizumab alone versus chemotherapy. Hazard and Odds Ratios (HR/OR) for primary (overall survival, OS) and secondary endpoints (progression-free survival, PFS and objective response rate, ORR) were extracted and cumulated by adopting a random-effect model with 95% confidence interval. Four clinical trials that enrolled 2,754 patients including 1,252 with PD-L1 expression in ≥50% of cells were examined. We did not find a significant interaction (P = 0.16) between an add-on strategy and head-to-head comparisons with pembrolizumab for OS (HRs in favor of immunotherapy of 0.50 and 0.67, respectively). A significant quantitative interaction favoring the add-on strategy was found for PFS and ORR (P < 0.001), with a HR for PFS of 0.36 with the add-on strategy and 0.65 in head-to head comparisons, and an OR for ORR of 5.35 and 1.58, respectively. In absence of planned prospective noninferiority trials addressing this issue, addition of chemotherapy to pembrolizumab appears to decrease tumor size and delay disease progression significantly more than pembrolizumab alone, but has no impact on OS. We conclude that the data support deciding between both treatment options on an individual basis by considering a patients' clinical status and disease characteristics.

Molecular heterogeneity assessment by next-generation sequencing and response to gefitinib of EGFR mutant advanced lung adenocarcinoma

Cancer molecular heterogeneity might explain the variable response of EGFR mutant lung adenocarcinomas to tyrosine kinase inhibitors (TKIs). We assessed the mutational status of 22 cancer genes by next-generation sequencing (NGS) in poor, intermediate or good responders to first-line gefitinib. Clinical outcome was correlated with Additional Coexisting Mutations (ACMs) and the EGFR Proportion of Mutated Alleles (PMA). Thirteen ACMs were found in 10/17 patients: TP53 (n=6), KRAS (n=2), CTNNB1 (n=2), PIK3CA, SMAD4 and MET (n=1 each). TP53 mutations were exclusive of poor/intermediate responders (66.7% versus 0, p=0.009). Presence of ACMs significantly affected both PFS (median 3.0 versus 12.3 months, p=0.03) and survival (3.6 months versus not reached, p=0.03). TP53 mutation was the strongest negative modifier (median PFS 4.0 versus 14.0 months). Higher EGFR PMA was present in good versus poor/intermediate responders. Median PFS and survival were longer in patients with EGFR PMA ≥0.36 (12.0 versus 4.0 months, p=0.31; not reached versus 18.0 months, p=0.59). Patients with an EGFR PMA ≥0.36 and no ACMs fared significantly better (p=0.03), with a trend towards increased survival (p=0.06). Our exploratory data suggest that a quantitative (PMA) and qualitative (ACMs) molecular heterogeneity assessment using NGS might be useful for a better selection of patients.

Predictive and Prognostic Role of Tumor-Infiltrating Lymphocytes for Early Breast Cancer According to Disease Subtypes: Sensitivity Analysis of Randomized Trials in Adjuvant and Neoadjuvant Setting

BACKGROUND

The role of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is still an issue for clinical research. Toward this end, a sensitivity analysis of neoadjuvant and adjuvant randomized clinical trials was performed according to disease subtypes.

METHODS

Pathological complete responses (pCRs) after neoadjuvant treatment according to the presence or absence of lymphocyte-predominant BC (LPBC) were extracted and cumulated as odds ratios (ORs) by adopting a random-effects model by subtype. Overall survival hazard ratios as a function of 10% incremental values of stromal TILs (sTILs) in adjuvant trials were extracted. The interaction test was adopted to determine the differential effect according to the subtype.

RESULTS

Eight trials (5,514 patients) were identified. With regard to neoadjuvant setting (4 studies), a significant interaction (p < .0001) according to LPBC was found. The presence of LPBC was associated with a 29.5% increase in pCR rate compared with non-LPBC (p < .0001). The pCR rate was significantly higher in patients with LPBC in triple-negative BC (TNBC) and HER2-positive BC settings, with an absolute difference of 15.7% (95% confidence interval [CI], 4.9%-26.2%) and 33.3% (95% CI, 23.6%-42.7%), respectively. With respect to the adjuvant setting (4 studies), a significant interaction (p < .0001) according to sTILs was found. A survival benefit was more likely to be determined for HER2-positive BC (p = .025) and TNBC (p < .0001), with no statistically significant difference for estrogen receptor-positive/HER2-negative disease.

CONCLUSION

Despite the retrospective nature of this analysis, the presence of TILs may represent a robust predictive and prognostic marker for BC, particularly for TNBC and HER2-positive disease.

Integrating the molecular background of targeted therapy and immunotherapy in lung cancer: a way to explore the impact of mutational landscape on tumor immunogenicity

The results of randomized clinical trials employing immune checkpoint inhibitors for pre-treated advanced non-small-cell lung cancer (NSCLC) have recently revolutionised the standard available option for this disease setting. Nevertheless, the validation of reliable predictive biomarkers, able to define that proportion of patients most likely to benefit from immunotherapy, represents a crucial and still unsolved issue. This intensive research aimed at selecting potentially predictive biomarkers for immunotherapy is developed together with a wide range of analyses investigating the molecular profiling of lung cancer, leading to the spontaneous question of how these two parallel aspects of the same disease may coexist and influence one another. The potential impact of the mutational landscape of lung cancer on tumor immunogenicity (in both oncogene-addicted and molecularly unselected disease) will be explored and discussed in this review in order to begin to answer the unsolved questions.

Differential Activity of Nivolumab, Pembrolizumab and MPDL3280A according to the Tumor Expression of Programmed Death-Ligand-1 (PD-L1): Sensitivity Analysis of Trials in Melanoma, Lung and Genitourinary Cancers

Background

The potential predictive role of programmed death-ligand-1 (PD-L1) expression on tumor cells in the context of solid tumor treated with checkpoint inhibitors targeting the PD-1 pathway represents an issue for clinical research.

Methods

Overall response rate (ORR) was extracted from phase I-III trials investigating nivolumab, pembrolizumab and MPDL3280A for advanced melanoma, non-small cell lung cancer (NSCLC) and genitourinary cancer, and cumulated by adopting a fixed and random-effect model with 95% confidence interval (CI). Interaction test according to tumor PD-L1 was accomplished. A sensitivity analysis according to adopted drug, tumor type, PD-L1 cut-off and treatment line was performed.

Results

Twenty trials (1,475 patients) were identified. A significant interaction (p<0.0001) according to tumor PD-L1 expression was found in the overall sample with an ORR of 34.1% (95% CI 27.6-41.3%) in the PD-L1 positive and 19.9% (95% CI 15.4-25.3%) in the PD-L1 negative population. ORR was significantly higher in PD-L1 positive in comparison to PD-L1 negative patients for nivolumab and pembrolizumab, with an absolute difference of 16.4% and 19.5%, respectively. A significant difference in activity of 22.8% and 8.7% according to PD-L1 was found for melanoma and NSCLC, respectively, with no significant difference for genitourinary cancer.

Conclusion

Overall, the three antibodies provide a significant differential effect in terms of activity according to PD-L1 expression on tumor cells. The predictive value of PD-L1 on tumor cells seems to be more robust for anti-PD-1 antibody (nivolumab and pembrolizumab), and in the context of advanced melanoma and NSCLC.

Balancing activity and tolerability of neoadjuvant paclitaxel- and docetaxel-based chemotherapy for HER2-positive early stage breast cancer: sensitivity analysis of randomized trials

Paclitaxel and docetaxel represent the most adopted taxanes in the neoadjuvant treatment of HER2-positive breast cancer. Questions still remain with regard to their difference in terms of activity and tolerability. Events for pathological complete response (pCR), severe and febrile neutropenia (FN), and severe neurotoxicity were pooled by adopting a fixed- and random-effect model. A sensitivity analysis to test for the interaction between paclitaxel and docetaxel was accomplished. Absolute differences with 95% confidence intervals (CIs) and the number of patients needed to treat/harm (NNT/NNH) were calculated to derive the Likelihood of being Helped or Harmed (LHH). Data from 15 trials (3601 patients) were included. Paclitaxel significantly increases pCR rate by 6.8% in comparison with docetaxel (43.4%, 95% CI 41.1-45.7% versus 36.6%, 95% CI 34.3-39.0%, p=0.0001), regardless of the chemotherapy backbone, with an absolute difference of 9% and 9.2% for anthracycline-based or free-regimens. Paclitaxel significantly improves pCR versus docetaxel with a single HER2-inhibition by 6.7% (p=0.0012), with no difference if combined with a dual HER2-inhibition. Severe neutropenia and FN are significantly lower with paclitaxel, with an absolute difference of 32.4% (p<0.0001) and 2.5% (p=0.0059), respectively. Conversely, severe neurotoxicity is slightly higher with paclitaxel (3%, p=0.0001). The LHH ratio calculated for pCR and severe neutropenia is 2.0 and 0.7 for paclitaxel and docetaxel. Although the activity of neoadjuvant paclitaxel and docetaxel HER2-positive breast cancer is considered similar, the slight advantage in pCR, the significantly lower neutropenia and FN, do favor paclitaxel (in the weekly fashion) over docetaxel, despite the slightly worst neurotoxicity.

Impact of neoadjuvant single or dual HER2 inhibition and chemotherapy backbone upon pathological complete response in operable and locally advanced breast cancer: Sensitivity analysis of randomized trials

The role of the dual HER2 inhibition, and the best chemotherapy backbone for neoadjuvant chemotherapy still represent an issue for clinical practice. A literature-based meta-analysis exploring single versus dual HER2 inhibition in terms of pathological complete response (pCR, breast plus axilla) rate and testing the interaction according to the chemotherapy (anthracyclines-taxanes or taxanes) was conducted. In addition, an event-based pooled analysis by extracting activity and safety events and deriving 95% confidence intervals (CI) was accomplished. Fourteen trials (4149 patients) were identified, with 6 trials (1820 patients) included in the meta-analysis and 31 arms (14 trials, 3580 patients) in the event-based pooled analysis. The dual HER2 inhibition significantly improves pCR rate, in the range of 16-19%, regardless of the chemotherapy backbone (relative risk 1.37, 95% CI 1.23-1.53, p<0.0001); pCR was significantly higher in the hormonal receptor negative population, regardless of the HER2 inhibition and type of chemotherapy. pCR and the rate of breast conserving surgery was higher when anthracyclines were added to taxanes, regardless of the HER2 inhibition. Severe neutropenia was higher with the addition of anthracyclines to taxanes, with an absolute difference of 19.7%, despite no differences in febrile neutropenia. While no significant differences according to the HER2 inhibition were found in terms of cardiotoxicity, a slightly difference for grade 3-4 (1.2%) against the addition of anthracyclines was calculated. The dual HER2 inhibition for the neoadjuvant treatment of HER2-positive breast cancer significantly increases pCR; the combination of anthracyclines, taxanes and anti-Her2 agents should be currently considered the standard of care.