Tumor genotyping using cell-free plasma DNA (cfDNA) has the potential to allow noninvasive assessment of tumor biology, yet many existing assays are cumbersome and vulnerable to false-positive ...results. We sought to determine whether droplet digital PCR (ddPCR) of cfDNA would allow highly specific and quantitative assessment of tumor genotype.
ddPCR assays for EGFR, KRAS, and BRAF mutations were developed using plasma collected from patients with advanced lung cancer or melanoma of a known tumor genotype. Sensitivity and specificity were determined using cancers with nonoverlapping genotypes as positive and negative controls. Serial assessment of response and resistance was studied in patients with EGFR-mutant lung cancer on a prospective trial of erlotinib.
We identified a reference range for EGFR L858R and exon 19 deletions in specimens from KRAS-mutant lung cancer, allowing identification of candidate thresholds with high sensitivity and 100% specificity. Received operative characteristic curve analysis of four assays demonstrated an area under the curve in the range of 0.80 to 0.94. Sensitivity improved in specimens with optimal cfDNA concentrations. Serial plasma genotyping of EGFR-mutant lung cancer on erlotinib demonstrated pretreatment detection of EGFR mutations, complete plasma response in most cases, and increasing levels of EGFR T790M emerging before objective progression.
Noninvasive genotyping of cfDNA using ddPCR demonstrates assay qualities that could allow effective translation into a clinical diagnostic. Serial quantification of plasma genotype allows noninvasive assessment of response and resistance, including detection of resistance mutations up to 16 weeks before radiographic progression.
Programmed death 1 is an immune checkpoint that suppresses antitumor immunity. Nivolumab, a fully human immunoglobulin G4 programmed death 1 immune checkpoint inhibitor antibody, was active and ...generally well tolerated in patients with advanced solid tumors treated in a phase I trial with expansion cohorts. We report overall survival (OS), response durability, and long-term safety in patients with non-small-cell lung cancer (NSCLC) receiving nivolumab in this trial.
Patients (N = 129) with heavily pretreated advanced NSCLC received nivolumab 1, 3, or 10 mg/kg intravenously once every 2 weeks in 8-week cycles for up to 96 weeks. Tumor burden was assessed by RECIST (version 1.0) after each cycle.
Median OS across doses was 9.9 months; 1-, 2-, and 3-year OS rates were 42%, 24%, and 18%, respectively, across doses and 56%, 42%, and 27%, respectively, at the 3-mg/kg dose (n = 37) chosen for further clinical development. Among 22 patients (17%) with objective responses, estimated median response duration was 17.0 months. An additional six patients (5%) had unconventional immune-pattern responses. Response rates were similar in squamous and nonsquamous NSCLC. Eighteen responding patients discontinued nivolumab for reasons other than progressive disease; nine (50%) of those had responses lasting > 9 months after their last dose. Grade 3 to 4 treatment-related adverse events occurred in 14% of patients. Three treatment-related deaths (2% of patients) occurred, each associated with pneumonitis.
Nivolumab monotherapy produced durable responses and encouraging survival rates in patients with heavily pretreated NSCLC. Randomized clinical trials with nivolumab in advanced NSCLC are ongoing.
Non-small-cell lung cancers (NSCLCs) harboring mutations in MET exon 14 and its flanking introns may respond to c-Met inhibitors. We sought to describe the clinical, pathologic, and genomic ...characteristics of patients with cancer with MET exon 14 mutations.
We interrogated next-generation sequencing results from 6,376 cancers to identify those harboring MET exon 14 mutations. Clinical characteristics of MET exon 14 mutated NSCLCs were compared with those of NSCLCs with activating mutations in KRAS and EGFR. Co-occurring genomic mutations and copy number alterations were identified. c-Met immunohistochemistry and real-time polymerase chain reaction to detect exon 14 skipping were performed where sufficient tissue was available.
MET exon 14 mutations were identified in 28 of 933 nonsquamous NSCLCs (3.0%) and were not seen in other cancer types in this study. Patients with MET exon 14-mutated NSCLC were significantly older (median age, 72.5 years) than patients with EGFR-mutant (median age, 61 years; P < .001) or KRAS-mutant NSCLC (median age, 65 years; P < .001). Among patients with MET exon 14 mutations, 68% were women, and 36% were never-smokers. Stage IV MET exon 14-mutated NSCLCs were significantly more likely to have concurrent MET genomic amplification (mean ratio of MET to chromosome 7, 4.3) and strong c-Met immunohistochemical expression (mean H score, 253) than stage IA to IIIB MET exon 14-mutated NSCLCs (mean ratio of MET to chromosome 7, 1.4; P = .007; mean H score, 155; P = .002) and stage IV MET exon 14-wild-type NSCLCs (mean ratio of MET to chromosome 7, 1.2; P < .001; mean H score, 142; P < .001). A patient whose lung cancer harbored a MET exon 14 mutation with concurrent genomic amplification of the mutated MET allele experienced a major partial response to the c-Met inhibitor crizotinib.
MET exon 14 mutations represent a clinically unique molecular subtype of NSCLC. Prospective clinical trials with c-Met inhibitors will be necessary to validate MET exon 14 mutations as an important therapeutic target in NSCLC.
Small-cell lung cancer Jackman, David M; Johnson, Bruce E
Lancet,
10/2005, Letnik:
366, Številka:
9494
Journal Article, Book Review
Recenzirano
Small-cell lung carcinoma is an aggressive form of lung cancer that is strongly associated with cigarette smoking and has a tendency for early dissemination. Increasing evidence has implicated ...autocrine growth loops, proto-oncogenes, and tumour-suppressor genes in its development. At presentation, the vast majority of patients are symptomatic, and imaging typically reveals a hilar mass. Pathology, in most cases of samples obtained by bronchoscopic biopsy, should be undertaken by pathologists with pulmonary expertise, with the provision of additional tissue for immunohistochemical stains as needed. Staging should aim to identify any evidence of distant disease, by imaging of the chest, upper abdomen, head, and bones as appropriate. Limited-stage disease should be treated with etoposide and cisplatin and concurrent early chest irradiation. All patients who achieve complete remission should be considered for treatment with prophylactic cranial irradiation, owing to the high frequency of brain metastases in this disease. Extensive-stage disease should be managed by combination chemotherapy, with a regimen such as etoposide and cisplatin administered for four to six cycles. Thereafter, patients with progressive or recurrent disease should be treated with additional chemotherapy. For patients who survive long term, careful monitoring for development of a second primary tumour is necessary, with further investigation and treatment as appropriate.
Activating mutations in the epidermal growth factor receptor gene (EGFR) predict for prolonged progression-free survival in patients with advanced non–small cell lung cancer (NSCLC) treated with EGFR ...tyrosine kinase inhibitors (EGFR-TKIs) versus chemotherapy. Long-term survival outcomes, however, remain undefined. The objective of this study was to determine the 5-year survival in these patients and identify clinical factors associated with overall survival (OS).
Patients with EGFR-mutant metastatic lung adenocarcinoma who had been treated with erlotinib or gefitinib at Dana-Farber Cancer Institute between 2002 and 2009 were included. OS was analyzed.
Among 137 patients, median progression-free survival and OS were 12.1 months (95% CI: 10.2–13.5) and 30.9 months (95% CI: 28.2–35.7), respectively. Twenty patients (14.6%) were 5-year survivors. In multivariate analysis, exon 19 deletions (hazard ratio HR = 0.63, 95% CI: 0.44–0.91, p = 0.01), absence of extrathoracic (HR = 0.62, 95% CI: 0.41–0.93, p = 0.02) or brain metastasis (HR = 0.48, 95% CI: 0.30–0.77, p = 0.002), and not a current smoker (HR = 0.23, 95% CI: 0.09–0.59, p = 0.002) were associated with prolonged OS. Age; sex; stage at diagnosis; liver, bone, or adrenal metastasis; specific TKI; and line of TKI therapy were not associated with OS.
Our data suggest that the rate of 5-year survival among patients with EGFR-mutant metastatic lung adenocarcinoma treated with erlotinib or gefitinib is 14.6%. Exon 19 deletions and absence of extrathoracic or brain metastasis are associated with prolonged survival. On the basis of our findings, clinicians can gain an enhanced estimation of long-term outcomes in this population.
Exon 20 insertions are the third most common family of epidermal growth factor receptor (EGFR) mutations found in non–small-cell lung cancer (NSCLC). Little is known about cancers harboring these ...mutations aside from their lack of response to EGFR tyrosine kinase inhibitors, impairing the development of effective targeted therapies.
NSCLC patients with EGFR genotyping were studied using a mechanism approved by the Institutional Review Board. Cancers with exon 20 insertions were indentified, sequences were characterized, and effectiveness of different treatment regimens was reviewed retrospectively. Clinical characteristics and survival were compared with cancers harboring common EGFR mutations and cancers with wild-type EGFR.
One thousand eighty-six patients underwent EGFR genotyping from 2004 to 2012. Twenty seven (2.5%) harbored exon 20 insertions, making up 9.2% of all cancers with documented EGFR mutations. Compared with wild-type cancers, those with exon 20 insertions were more commonly found in never-smokers and Asian patients. Insertion sequences were highly variable, with the most common variant (V769_D770insASV) making up only 22% of cases. Median survival of patients with exon 20 insertions was 16 months, similar to the survival of wild-type cancers and shorter than the survival of cancers with common EGFR mutations.
Patients with EGFR exon 20 insertions have similar clinical characteristics to those with common EGFR mutations but a poorer prognosis. The prevalence of this subset of NSCLC is similar to that of other genotype-defined subsets of lung adenocarcinoma (e.g. those with BRAF mutations, HER2 insertions, ROS1 rearrangements) and is a population of interest for trials of new targeted therapies.
Clinical responses to immune checkpoint blockade by anti-programmed cell death protein-1 (PD-1)/PD-L1 monoclonal antibodies in non–small-cell lung cancer (NSCLC) are associated with PD-L1 expression ...and smoking status. We aimed to determine the expression profile of PD-1 and its ligands, PD-L1 and PD-L2, in both smokers and never smokers patients with KRAS-mutant NSCLC.
We retrospectively analyzed the clinical and molecular characteristics of 114 KRAS-mutant NSCLC patients (84 smokers and 30 never smokers) and their clinical tumor samples for the expression of PD-1, PD-L1, and PD-L2 by immunohistochemistry (IHC). We used murine monoclonal antibodies anti-PD-L1 (clone 9A11) and anti-PD-L2 (clone 9E5) to examine for tumor cell expression (0, negative; 1, weak; 2, moderate; 3, intense) and anti-PD-1 (clone EH33) for tumor-infiltrating lymphocytes.
PD-L1 expression was detected in 27 of 114 patients (24%; 95% confidence interval CI, 16–33%) and associated with smoking status (current smokers, 44%; former smokers, 20%; never smokers, 13%; p = 0.03). Higher intensity of PD-L1 expression (IHC-2+/IHC-3+) was more frequently observed in smokers and associated with more pack-years. PD-L2 was positive in 54 of 114 patients (47%; 95% CI, 38–57%) and not related to smoking status. PD-1-positive tumor-infiltrating lymphocytes were present in 77 of 114 tumor specimens tested (68%; 95% CI, 59–77%) including 21 of 27 samples with PD-L1 expression and 39 of 54 samples with PD-L2-positive expression. We found that PD-L1 expression fades with the age of the specimens used for analyses decreasing beyond 3 years (p = 0.016).
The expression of PD-1 and its ligands PD-L1 and PD-L2 is heterogeneous within KRAS-mutant NSCLC and suggests an inducible expression of PD-L1 by smoking.
The impact of epidermal growth factor receptor (EGFR) and KRAS genotypes on outcomes with erlotinib or gefitinib therapy continues to be debated. This study combines patient data from five trials in ...predominantly Western populations to assess the impact of EGFR and KRAS mutations on first-line therapy with an EGFR-tyrosine kinase inhibitor (TKI) and compare clinical versus molecular predictors of sensitivity.
Chemotherapy-naïve patients with advanced non-small cell lung cancer and known EGFR mutation status treated with erlotinib or gefitinib monotherapy as part of a clinical trial were eligible for inclusion. Patients received daily erlotinib (150 mg) or gefitinib (250 mg) until disease progression or unacceptable toxicity. Data were collected in a password-protected web database. Clinical outcomes were analyzed to look for differences based on EGFR and KRAS genotypes, as well as clinical characteristics.
Patients (223) from five clinical trials were included. Sensitizing EGFR mutations were associated with a 67% response rate, time to progression (TTP) of 11.8 months, and overall survival of 23.9 months. Exon 19 deletions were associated with longer median TTP and overall survival compared with L858R mutations. Wild-type EGFR was associated with poorer outcomes (response rate, 3%; TTP, 3.2 months) irrespective of KRAS status. No difference in outcome was seen between patients harboring KRAS transition versus transversion mutations. EGFR genotype was more effective than clinical characteristics at selecting appropriate patients for consideration of first-line therapy with an EGFR-TKI.
EGFR mutation status is associated with sensitivity to treatment with an EGFR-TKI in patients with advanced non-small cell lung cancer. Patients harboring sensitizing EGFR mutations should be considered for first-line erlotinib or gefitinib.
NUT midline carcinomas (NMCs) comprise a group of highly aggressive tumors that have been reported primarily in the head, neck, and mediastinum of younger individuals. These tumors overexpress the ...nuclear protein in the testis (NUT), most commonly due to a chromosomal translocation that fuses the NUT gene on chromosome 15 with the BRD4 gene on chromosome 19. Although the earliest recognized cases were described in the thymus or mediastinum, an extensive survey for NMCs among malignant thymic or other mediastinal neoplasms has not been reported. We examined NUT expression in 114 cases of poorly differentiated carcinomas or unclassified mediastinal malignancies using a clinically validated NUT-specific monoclonal antibody. Four of 114 (3.5%) cases showed nuclear NUT expression. A NUT translocation was confirmed by fluorescence in situ hybridization in 3 of these cases. These tumors arose in 2 men and 2 women with a median age of 50 years (range, 28 to 68 y). Three of the tumors were originally diagnosed as undifferentiated epithelioid or round cell malignant neoplasms; 1 tumor contained focal squamous differentiation and was originally diagnosed as a poorly differentiated squamous carcinoma of probable thymic origin. We find that the incidence of NMC within the mediastinum, particularly among undifferentiated tumors, is similar to that reported at other anatomic sites. NMC should be considered in the differential diagnosis of any poorly differentiated epithelioid mediastinal tumor, regardless of age.