Rita Chiari

Phosphoinositide-3-Kinase Catalytic Alpha and KRAS Mutations are Important Predictors of Resistance to Therapy with Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Patients with Advanced Non-small Cell Lung Cancer

Background: Specific mutations of the epidermal growth factor receptor (EGFR) gene are predictive for favorable response to tyrosine kinase inhibitors (TKIs) and are associated with a good prognosis. In contrast, Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation has been shown to predict poor response to such therapy. Nevertheless, tumor that initially responds to EGFR-TKIs almost inevitably becomes resistant later. Other mechanisms of resistance to EGFR inhibitors could involve activating mutations of the other main EGFR effector pathway, i.e., the phosphoinositide-3-kinase/phosphate and tensin homologue deleted from chromosome 10 (PTEN)/alpha serine/threonine protein kinase (AKT) pathway. The aim of this study was to investigate the role of phosphoinositide-3-kinase catalytic alpha (PIK3CA), EGFR, and KRAS gene mutations in predicting response and survival in patients with non-small cell lung cancer (NSCLC) treated with EGFR-TKIs. Patients and Methods: A total of 166 patients with advanced NSCLC treated with EGFR-TKI with available archival tissue specimens were included. PIK3CA, EGFR, and KRAS mutations were analyzed using polymerase chain reaction-based sequencing. Results: EGFR mutation was detected in 25.3% of patients, PIK3CA mutation in 4.1%, and KRAS mutation in 6.7%. PIK3CA mutation correlated with shorter median time to progression (TTP) (p = 0.01) and worse overall survival (OS) (p < 0.001). EGFR mutation (p < 0.0001) correlated with favorable response to TKIs treatment and longer TTP (p < 0.0001). KRAS mutation correlated with progressive disease (p = 0.05) and shorter median TTP (p = 0.003) but not with OS. Cox multivariate analysis including histology and performance status showed that PIK3CA mutation was an independent factor to predict worse OS (p = 0.0001) and shorter TTP (p = 0.03), while KRAS mutation to predict shorter TTP (p = 0.01). Conclusion: PIK3CA and KRAS mutations seem to be indicators of resistance and poor survival in patients with NSCLC treated with EGFR-TKIs.

Early Prediction of Response to Tyrosine Kinase Inhibitors by Quantification of EGFR Mutations in Plasma of NSCLC Patients.

Introduction: The potential to accurately quantify epidermal growth factor receptor (EGFR) mutations in plasma from non–small-cell lung cancer patients would enable more rapid and more frequent analyses to assess disease status; however, the utility of such analyses for clinical purposes has only recently started to explore. Methods: Plasma samples were obtained from 69 patients with EGFR-mutated tumors and 21 negative control cases. EGFR mutations in plasma were analyzed by a standardized allele-specific polymerase chain reaction (PCR) test and ultra-deep next-generation sequencing (NGS). A semiquantitative index (SQI) was derived from dilutions of known EGFR mutation copy numbers. Clinical responses were evaluated by Response Evaluation Criteria in Solid Tumors 1.1 criteria and expressed as percent tumor shrinkage. Results: The sensitivity and specificity of the PCR test and NGS assay in plasma versus tissue were 72% versus 100% and 74% versus 100%, respectively. Quantitative indices by the PCR test and NGS were significantly correlated (p < 0.001). EGFR testing at baseline and serially at 4 to 60 days during tyrosine kinase inhibitor therapy revealed a progressive decrease in SQI, starting from day 4, in 95% of cases. The rate of SQI decrease correlated with percent tumor shrinkage at 2 months (p < 0.0001); at 14 days, it was more than 50% in 70% of patients (rapid responders). In two patients with slow response, an early increase in the circulating levels of the T790M mutation was observed. No early T790M mutations were seen in plasma samples of rapid responders. Conclusions: Quantification of EGFR mutations from plasma with a standardized PCR test is feasible. To our knowledge, this is the first study showing a strong correlation between the EGFR SQI in the first days of treatment and clinical response with relevant implications for patient management.

Impact of specific mutant KRAS on clinical outcome of EGFR-TKI-treated advanced non-small cell lung cancer patients with an EGFR wild type genotype

INTRODUCTION This retrospective study was undertaken to investigate the impact of specific mutant KRAS on clinical outcome to either gefitinib or erlotinib (EGFR tyrosine kinase inhibitor, EGFR-TKI) in patients with EGFR wild type (WT) advanced non-small cell lung cancer (NSCLC). METHODS Patients with an EGFR WT genotype who were treated with an EGFR-TKI for advanced disease at our Institution were identified. Simultaneous availability of KRAS mutation status was required for study inclusion. RESULTS Sixty-seven patients were eligible. Median age was 60 years (39-84), and 10 patients (14.9%) had received an EGFR-TKI as upfront therapy. Overall, the median progression-free survival (PFS) and overall survival (OS) were 2.9 months and 18.0 months, respectively. KRAS mutant patients (n=18) experienced a significantly shorter PFS compared with those carrying a KRAS WT genotype (n=49) (1.6 months vs 3.0 months, respectively, P=0.04; HR=1.92). However, within the KRAS mutant group a great variability in terms of sensitivity to treatment was noted (PFS ranging from 0.7 months to 38.7 months). KRAS codon 13 mutant patients (n=4) experienced the worse outcome when compared with KRAS codon 12 mutants (n=14) and KRAS WT patients (P<0.0001 and P=0.01 for PFS and OS, respectively). CONCLUSIONS Though we found that EGFR WT/KRAS mutant advanced NSCLC patients are associated with an increased resistance to treatment, specific mutant KRAS may account for differential sensitivity to an EGFR-TKI. KRAS codon 13 mutants are those who seem to experience the worse clinical outcome.

Association of Cytidine Deaminase and Xeroderma Pigmentosum Group D Polymorphisms with Response, Toxicity, and Survival in Cisplatin/Gemcitabine-Treated Advanced Non-small Cell Lung Cancer Patients

Background: Selecting patients according to key genetic characteristics may help to tailor chemotherapy and optimize the treatment in non-small cell lung cancer (NSCLC). Genetic variations in drug metabolism may affect the clinical response, toxicity, and prognosis of NSCLC patients treated with cisplatin/gemcitabine-based therapy. Patients and Methods: We evaluated seven single-nucleotide polymorphisms of six genes CDA Lys27Gln (A/C); CDA C435T; ERCC1 C118T; XRCC3 Thr241Met (C/T); XPD Lys751Gln (A/C); P53 Arg72Pro (G/C), and RRM1 C524T in 192 chemotherapy-naive patients with advanced NSCLC treated with cisplatin/gemcitabine-based regimen by TaqMan probe-based assays with 7300 Real-Time PCR System, using genomic DNA extracted from blood samples. Results: The CDA 435 T/T genotype was significantly associated with better response (p = 0.03). The CDA 435 C/T genotype was associated with a significantly increased risk of nonhematological toxicity of grade ≥3 (p = 0.02) after adjusting for performance status, age, and type of treatment regimen. In the multivariate Cox model, the XPD 751 C/C genotype was a significant prognostic factor of longer progression-free survival (p = 0.006). Conclusion: Our data suggest polymorphic variations of drug metabolic gene were associated with response and toxicity of cisplatin/gemcitabine-based therapy and progression-free survival of patients with advanced NSCLC.

Clinical outcome with platinum-based chemotherapy in patients with advanced nonsquamous EGFR wild-type non-small-cell lung cancer segregated according to KRAS mutation status.

BACKGROUND We hypothesized that KRAS mutations function as a marker of poor sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR wild-type (WT) non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Consecutive advanced nonsquamous EGFR WT NSCLCs treated at the Medical Oncology of Perugia with simultaneous assessment of KRAS mutation status were eligible. Anaplastic lymphoma kinase (ALK) gene status was known in roughly half of the patients who had KRAS WT. RESULTS Two hundred four patients were included. Among them, the 77 individuals carrying a KRAS-mutant phenotype experienced a significantly inferior outcome in terms of response rate (P = .04), disease control rate (P = .05), and progression-free survival (PFS) (P = .05) compared with the EGFR WT/KRAS WT population. The association between KRAS mutation and shorter PFS remained statistically significant at multivariate analysis (hazard ratio [HR], 1.45). In addition, patients with KRAS mutations reported a significantly shorter overall survival (OS) compared with patients with EGFR WT/KRAS WT/ALK negativity (n = 64) (P = .02). Among patients with KRAS mutations, those harboring a mutation at codon 13 (n = 12) performed worse than those with a mutation at codon 12 (n = 62) in terms of both PFS and OS (P = .09 for both). CONCLUSION KRAS mutation appears to negatively affect sensitivity to first-line platinum-based chemotherapy in patients with advanced nonsquamous EGFR WT NSCLC. Studies on larger case series are needed to address differences in clinical outcome according to the type of mutation.

Long-Term Response to Gefitinib and Crizotinib in Lung Adenocarcinoma Harboring Both Epidermal Growth Factor Receptor Mutation and EML4-ALK Fusion Gene

Case Report A67-year-oldwhitewomanwhohadneversmokedandwasasymptomatic (Eastern Cooperative Oncology Group performance group status of 0) was diagnosed in 2004 with thyroid transcription factor 1–positive, ring cell subtype lung adenocarcinoma, stage IV (pleural implants and effusion, cT1N2M1a, TNM version 7.0; Fig 1A, hematoxylin and eosin staining of the 2004 sample). After six courses of first-line chemotherapy with cisplatin plus gemcitabine, disease stability was observed and she began receiving gefitinib treatment. A partial response was obtained after 3 months (Fig 2A, computed tomography [CT] scan before gefitinib therapy; Fig 2B, CT scan after 3 months of gefitinib therapy), and then disease stability was achieved for 2 years (mutational status at that time was unknown). At disease progression, the patient received carboplatin plus pemetrexed chemotherapy for eight cycles, and stable disease was again achieved. After 1 year without therapy, she experienced disease progression (bone, pleural effusion, and mediastinal nodes). Sequence analysis was performed at this time on pleural biopsies that were obtained at the time of the first diagnosis and showed the L858R (2573T G) mutation at exon 21 of the epidermal growth factor receptor gene (EGFR; Fig 3A) with KRAS wild type (wt). For this reason, the patient began receiving treatment with a different reversible EGFR tyrosine kinase inhibitor (TKI), erlotinib, and after 3 months, she began receiving treatment with an irreversible EGFR TKI (afatinib), which was discontinued after 2 months because of disease progression. In June 2009, third-line chemotherapy with taxotere plus gemcitabine was administered for 10 cycles and stable disease was achieved. A new lung biopsy specimen was obtained in December 2009 that confirmed the same histology (Fig 1B) but a different molecular profile at sequence analysis, namely EGFR wt (Fig 3B) and KRAS wt. The EGFR analysis (exons 18, 19, 20, and 21) was performed by direct sequencing and confirmed by a therascreen EGFR RGQ PCR Kit (Qiagen, Germantown, MD) on both the 2004 and the 2009 samples. In May 2010, pemetrexed therapy was resumed and administered for six cycles when disease progressed at known sites. The presence of ALK translocation in the 2009 biopsy specimen was detected by an ALK break-apart fluorescent in situ hybridization assay, whereas the fluorescent in situ hybridization analysis of the first specimen from 2004 (performed in the Department of Pathology of Antwerp University Hospital, Antwerp, Belgium) was uninformative. Both the 2004 and the 2009 specimens scored positive by immunohistochemistry (3 ) performed by the Pathology Department at our hospital (Figs 4A and 4B). In September 2010, the patient entered a phase II study of PF-02341066 (crizotinib) in EML4/ALK-positive lung cancer and obtained a partial response after 6 weeks of treatment (Fig 2C, CT scan before crizotinib therapy; Fig 2D, CT scan after 6 weeks of crizotinib therapy) that lasted 25 months. In November 2012, a brain CT scan showed multiple asymptomatic brain lesions but disease stability at other known sites. It was decided that whole-brain radiotherapy (24 Gy) would be performed and that crizotinib treatment would be continued.

Italian, Multicenter, Phase III, Randomized Study of Cisplatin Plus Etoposide With or Without Bevacizumab as First-Line Treatment in Extensive-Disease Small-Cell Lung Cancer: The GOIRC-AIFA FARM6PMFJM Trial

Purpose Considering promising results in phase II studies, a randomized phase III trial was designed to assess the efficacy of adding bevacizumab to first-line cisplatin plus etoposide for treatment of extensive-disease (ED) small-cell lung cancer (SCLC). Patients and Methods Treatment-naive patients with ED-SCLC were randomly assigned to receive either cisplatin plus etoposide (arm A) or the same regimen with bevacizumab (arm B) for a maximum of six courses. In the absence of progression, patients in arm B continued bevacizumab alone until disease progression or for a maximum of 18 courses. The primary end point was overall survival (OS). Results Two hundred four patients were randomly assigned and considered in intent-to-treat analyses (103 patients in arm A and 101 patients in arm B). At a median follow-up of 34.9 months in arm A and arm B, median OS times were 8.9 and 9.8 months, and 1-year survival rates were 25% and 37% (hazard ratio, 0.78; 95% CI, 0.58 to 1.06; P = .113), respectively. A statistically significant effect of bevacizumab on OS in patients who received maintenance was seen (hazard ratio, 0.60; 95% CI, 0.40 to 0.91; P = .011). Median progression-free survival times were 5.7 and 6.7 months in arm A and arm B, respectively ( P = .030). Regarding hematologic toxicity, no statistically significant differences were observed; for nonhematologic toxicity, only hypertension was more frequent in arm B (grade 3 or 4, 1.0% v 6.3% in arms A v B, respectively; P = .057). Conclusion The addition of bevacizumab to cisplatin and etoposide in the first-line treatment of ED-SCLC had an acceptable toxicity profile and led to a statistically significant improvement in progression-free survival, which, however, did not translate into a statistically significant increase in OS. Further research with novel antiangiogenic agents, particularly in the maintenance setting, is warranted.

Clinical impact of sequential treatment with ALK-TKIs in patients with advanced ALK-positive non-small cell lung cancer: Results of a multicenter analysis

OBJECTIVES Anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) is sensitive to treatment with an ALK-tyrosine kinase inhibitor (-TKI). However, the benefit of sequential treatment with a 2nd ALK-TKI in patients who fail a 1st ALK-TKI has been poorly addressed. MATERIALS AND METHODS We collected the data of 69 advanced ALK-positive NSCLCs who were treated with one or more ALK-TKIs at three Italian institutions. The clinical outcome of treatment with an ALK-TKI and the patterns of treatment upon failing a 1st ALK-TKI were recorded. RESULTS Objective response rate (ORR) and median progression-free survival (PFS) on a 1st ALK-TKI (mostly crizotinib) were 60.9% and 12 months, respectively. Of the 50 patients who progressed on a 1st ALK-TKI, 22 were further treated with a 2nd ALK-TKI (either ceritinib or alectinib), for whom an ORR of 86.4% and median PFS of 7 months, respectively, were reported. Conversely, 13 patients underwent rapid clinical/radiographic disease progression leading to death shortly after discontinuation of the 1st ALK-TKI, 7 patients were managed with a 1st ALK-TKI beyond progression, and 8 patients transitioned to other systemic treatments (mostly chemotherapy). Post-progression survival (PPS) significantly favored the 22 patients who were sequentially treated with a 2nd ALK-TKI over those who transitioned to other systemic treatments (P=0.03), but not versus those who were treated with a 1st ALK-TKI beyond progression (P=0.89). CONCLUSION Sequential treatment with a 2nd ALK-TKI is effective in patients who fail a 1st ALK-TKI. Continuous ALK-inhibition upon failing a 1st ALK-TKI may be associated with improved clinical outcome.

Selumetinib: a promising pharmacologic approach for KRAS-mutant advanced non-small-cell lung cancer.

Selumetinib is a potent and selective inhibitor of MEK1 and 2 that is currently being clinically developed for the treatment of several human malignancies. Initially administered as free-base suspension, a more convenient Hyd-sulfate capsule formulation has recently been developed. Phase I studies revealed that acneiform dermatitis was the dose-limiting toxicity of both the free-base and capsule formulation given two-times a day at the maximum tolerated doses of 100 and 75 mg, respectively, with the capsule formulation resulting into a significantly higher drug bioavailability. Importantly, as a MEK inhibitor, selumetinib could be particularly effective in tumors with a hyperactivated Ras/Raf/MEK/ERK pathway, which might be the case of KRAS-mutant non-small-cell lung cancers (NSCLCs). Accordingly, a recent randomized Phase II study evaluating docetaxel plus selumetinib or placebo in KRAS-mutant pretreated advanced NSCLC patients has demonstrated a significant improvement in terms of response rate, progression-free survival and patient-reported outcomes in favor of the combination arm. These positive results support further clinical evaluation of selumetinib in NSCLC, and confirmatory ongoing and future trials will assess its role according to KRAS-mutation status and in combination regimens with other targeted agents.

Activity of the EGFR-HER2 dual inhibitor afatinib in EGFR-mutant lung cancer patients with acquired resistance to reversible EGFR tyrosine kinase inhibitors.

BACKGROUND The purpose of this study was to evaluate the efficacy of afatinib in EGFR-mutant metastatic NSCLC patients with acquired resistance to erlotinib or gefitinib. MATERIALS AND METHODS We retrospectively analyzed the outcome of patients with EGFR-mutant advanced NSCLC treated with afatinib after failure of chemotherapy and EGFR TKIs. RESULTS A total of 96 individuals were included in the study. According to EGFR status, most patients (n = 63; 65.6%) harbored a deletion in exon 19, and de novo T790M mutation was detected in 2 cases (T790M and exon 19). Twenty-four (25%) patients underwent repeated biopsy immediately before starting afatinib and secondary T790M was detected in 8 (33%) samples. Among the 86 patients evaluable for efficacy, response rate was 11.6%, with a median progression free-survival (PFS) and overall survival (OS) of 3.9 and 7.3 months, respectively. No significant difference in PFS and OS was observed according to type of last therapy received before afatinib, type of EGFR mutation or adherence to Jackman criteria, and patients benefiting from afatinib therapy had longer PFS and OS (P < .001). Outcome results for repeated biopsy patients were similar to the whole population, with no evidence of response in T790M-positive patients. All patients were evaluable for toxicity, and 81% experienced an AE of any grade, with grade 3 to 4 AEs, mainly diarrhea and skin toxicity, occurring in 19 (20%) patients. CONCLUSION Our results showed that afatinib has only modest efficacy in a real life population of EGFR mutant NSCLC patients with acquired resistance to erlotinib or gefitinib.