Ikuo Sekine

Epidermal Growth Factor Receptor Gene Mutations and Increased Copy Numbers Predict Gefitinib Sensitivity in Patients With Recurrent Non–Small-Cell Lung Cancer

PURPOSE To evaluate epidermal growth factor receptor (EGFR) mutations and copy number as predictors of clinical outcome in patients with non-small-cell lung cancer (NSCLC) receiving gefitinib. PATIENTS AND METHODS Sixty-six patients with NSCLC who experienced relapse after surgery and received gefitinib were included. Direct sequencing of exons 18 to 24 of EGFR and exons 18 to 24 of ERBB2 was performed using DNA extracted from surgical specimens. Pyrosequencing and quantitative real-time polymerase chain reaction were performed to analyze the allelic pattern and copy number of EGFR. RESULTS Thirty-nine patients (59%) had EGFR mutations; 20 patients had deletional mutations in exon 19, 17 patients had missense mutations (L858R) in exon 21, and two patients had missense mutations (G719S or G719C) in exon 18. No mutations were identified in ERBB2. Response rate (82% [32 of 39 patients] v 11% [three of 27 patients]; P < .0001), time to progression (TTP; median, 12.6 v 1.7 months; P < .0001), and overall survival (median, 20.4 v 6.9 months; P = .0001) were significantly better in patients with EGFR mutations than in patients with wild-type EGFR. Increased EGFR copy numbers (> or = 3/cell) were observed in 29 patients (44%) and were significantly associated with a higher response rate (72% [21 of 29 patients] v 38% [14 of 37 patients]; P = .005) and a longer TTP (median, 9.4 v 2.6 months; P = .038). High EGFR copy numbers (> or = 6/cell) were caused by selective amplification of mutant alleles. CONCLUSION EGFR mutations and increased copy numbers were significantly associated with better clinical outcome in gefitinib-treated NSCLC patients.

KIF5B-RET fusions in lung adenocarcinoma

We identified in-frame fusion transcripts of KIF5B (the kinesin family 5B gene) and the RET oncogene, which are present in 1–2% of lung adenocarcinomas (LADCs) from people from Japan and the United States, using whole-transcriptome sequencing. The KIF5B-RET fusion leads to aberrant activation of RET kinase and is considered to be a new driver mutation of LADC because it segregates from mutations or fusions in EGFR, KRAS, HER2 and ALK, and a RET tyrosine kinase inhibitor, vandetanib, suppresses the fusion-induced anchorage-independent growth activity of NIH3T3 cells.

Palonosetron plus dexamethasone versus granisetron plus dexamethasone for prevention of nausea and vomiting during chemotherapy: a double-blind, double-dummy, randomised, comparative phase III trial

BACKGROUND Palonosetron is a second-generation 5-hydroxytryptamine 3 (5-HT(3))-receptor antagonist that has shown better efficacy than ondansetron and dolasetron in preventing chemotherapy-induced nausea and vomiting (CINV) in patients receiving moderately emetogenic chemotherapy, and similar efficacy to ondansetron in preventing CINV in patients receiving highly emetogenic chemotherapy. In this phase III, multicentre, randomised, double-blind, double-dummy, stratified, parallel-group, active-comparator trial, we assessed the efficacy and safety of palonosetron versus granisetron for chemotherapy-induced nausea and vomiting, both of which were administered with dexamethasone in patients receiving highly emetogenic chemotherapy. METHODS Between July 5, 2006, and May 31, 2007, 1143 patients with cancer who were receiving highly emetogenic chemotherapy (ie, cisplatin, or an anthracycline and cyclophosphamide combination [AC/EC]) were recruited from 75 institutions in Japan, and randomly assigned to either single-dose palonosetron (0.75 mg), or granisetron (40 microg/kg) 30 min before chemotherapy on day 1, both with dexamethasone (16 mg intravenously) on day 1 followed by additional doses (8 mg intravenously for patients receiving cisplatin or 4 mg orally for patients receiving AC/EC) on days 2 and 3. A non-deterministic minimisation method with a stochastic-biased coin was applied to the randomisation of patients. Covariates known to effect emetic risk, such as sex, age, and type of highly emetogenic chemotherapy, were used as stratification factors of minimisation to ensure balance between the treatment groups. Primary endpoints were the proportion of patients with a complete response (defined as no emetic episodes and no rescue medication) during the acute phase (0-24 h postchemotherapy; non-inferiority comparison with granisetron) and the proportion of patients with a complete response during the delayed phase (24-120 h postchemotherapy; superiority comparison with granisetron). The non-inferiority margin was predefined in the study protocol as a 10% difference between groups in the proportion of patients with complete response. The palonosetron dose of 0.75 mg was chosen on the basis of two dose-determining trials in Japanese patients. All patients who received study treatment and highly emetogenic chemotherapy were included in the efficacy analyses (modified intention to treat). This trial is registered with ClinicalTrials.gov, number NCT00359567. FINDINGS 1114 patients were included in the efficacy analyses: 555 patients in the palonosetron group and 559 patients in the granisetron group. 418 of 555 patients (75.3%) in the palonosetron group had complete response during the acute phase compared with 410 of 559 patients (73.3%) in the granisetron group (mean difference 2.9% [95% CI -2.70 to 7.27]). During the delayed phase, 315 of 555 patients (56.8%) had complete response in the palonosetron group compared with 249 of 559 patients (44.5%) in the granisetron group (p<0.0001). The main treatment-related adverse events were constipation (97 of 557 patients [17.4%] in the palonosetron group vs 88 of 562 [15.7%] in the granisetron group) and raised concentrations of serum aminotransferases (aspartate aminotransferase: 24 of 557 [4.3%] vs 34 of 562 [6.0%]; alanine aminotransferase: 16 of 557 [2.9%] vs 33 of 562 [5.9%]); no grade 4 main treatment-related adverse events were reported. INTERPRETATION When administered with dexamethasone before highly emetogenic chemotherapy, palonosetron exerts efficacy against chemotherapy-induced nausea and vomiting which is non-inferior to that of granisetron in the acute phase and better than that of granisetron in the delayed phase, with a comparable safety profile for the two treatments. FUNDING Taiho Pharmaceutical (Tokyo, Japan).

Comprehensive histologic analysis of ALK-rearranged lung carcinomas.

A subset (1% to 5%) of non-small-cell lung carcinomas harbors the EML4-ALK fusion gene. Data from previous studies on the histomorphology of ALK-rearranged lung cancer are inconsistent, and the specific histologic parameters that characterize this subset and how accurately such parameters predict underlying ALK abnormality remain uncertain. To answer these questions, we performed a comprehensive histologic analysis of 54 surgically resected, extensively sampled ALK-rearranged lung carcinomas and compared them with 100 consecutive resections of ALK-wild-type lung cancers. All 54 cases showed at least a focal adenocarcinoma component, and 3 and 2 cases had additional squamous and sarcomatoid differentiation, respectively. Solid or acinar growth pattern, cribriform structure, presence of mucous cells (signet-ring cells or goblet cells), abundant extracellular mucus, lack of lepidic growth, and lack of significant nuclear pleomorphism were more common in ALK-positive cancers. Two recognizable constellations of findings, a solid signet-ring cell pattern and a mucinous cribriform pattern, were present at least focally in the majority (78%) of ALK-positive tumors, but were rare (1%) in ALK-negative tumors. Multivariate analysis showed that a combination of these 2 patterns was the most powerful histologic indicator of ALK rearrangement. Characteristic histologies were present both in primary sites and in metastases. Thus, histologic findings may help to identify cases for ALK testing. However, none of the histologic parameters were completely sensitive or specific to ALK rearrangement, and histomorphology should not replace confirmatory molecular or immunohistochemical studies. ALK-positive cancers commonly showed coexpression of thyroid transcription factor-1 and p63, and its significance is currently unclear.

EGFR Mutations Predict Survival Benefit From Gefitinib in Patients With Advanced Lung Adenocarcinoma: A Historical Comparison of Patients Treated Before and After Gefitinib Approval in Japan

PURPOSE This study evaluated whether the presence of epidermal growth factor receptor (EGFR) mutations is a predictive marker for survival benefit from gefitinib and/or a prognostic marker in patients with advanced lung adenocarcinoma. PATIENTS AND METHODS Overall survival (OS) was compared between patients with advanced lung adenocarcinoma who began first-line systemic therapy before and after gefitinib approval in Japan (January 1999 to July 2001 and July 2002 to December 2004, respectively). Deletional mutations in exon 19 or the L858R mutation in exon 21 of EGFR were evaluated using high-resolution melting analysis. RESULTS EGFR mutations were detected in 136 (41%) of the 330 patients included in this study. OS was significantly longer among the EGFR-mutant patients treated after gefitinib approval compared with the OS of patients treated before gefitinib approval (median survival time [MST], 27.2 v 13.6 months, respectively; P < .001), whereas no significant survival improvement was observed in patients without EGFR mutations (MST, 13.2 v 10.4 months, respectively; P = .13). A significant interaction between the presence of EGFR mutations and a survival improvement was seen (P = .045). Among patients treated before gefitinib approval, those with EGFR mutations lived longer than those without EGFR mutations (MST, 13.6 v 10.4 months, respectively; P = .034). The response rates to first-line cytotoxic chemotherapy were not significantly different between patients with and without EGFR mutations (31% v 28%, respectively; P = .50). CONCLUSION EGFR mutations significantly predict both a survival benefit from gefitinib and a favorable prognosis in patients with advanced lung adenocarcinoma.

c-MET/phospho-MET protein expression and MET gene copy number in non-small cell lung carcinomas.

Introduction: The hepatocyte growth factor/MET pathway has been shown to cause tumor progression in several types of carcinomas. The aim of this study was to examine the correlations between c-MET/phospho-MET expression as well as MET gene copy number alterations and overall survival (OS) in non-small cell lung carcinomas (NSCLCs). Methods: We analyzed 906 NSCLCs including 704 adenocarcinomas (ADCs), 150 squamous cell carcinomas (SCCs), 43 sarcomatoid carcinomas, and 9 large cell carcinomas. The mutational status of epidermal growth factor receptor and K-ras and anaplastic lymphoma kinase rearrangements were retrospectively examined. We performed immunohistochemistry to detect c-MET/phospho-MET expression and MET gene copy number using bright-field in situ hybridization (BISH). Results: c-MET/phospho-MET expression and MET BISH positivity were observed in 22.2%, 5.6%, and 10.9% of NSCLCs, respectively; they were more prevalent in ADCs (27.3%, 6.9%, and 11.5%, respectively) and sarcomatoid carcinomas (20.9%, 9.3%, and 36.6%, respectively) than in SCCs and large cell carcinomas. Among ADCs, poorly differentiated cases exhibited c-MET expression and MET BISH positivity more commonly than well-differentiated ones. An analysis of all patients revealed that c-MET/phospho-MET expression and MET BISH positivity were not correlated with OS. However, when SCC cases were excluded, both univariate (p=0.019) and multivariate (p=0.020) analyses revealed a significant correlation between MET BISH positivity and OS. Conclusions: c-MET/phospho-MET expression and MET BISH positivity differed according to histological type. Among ADCs, c-MET expression and MET BISH positivity were more common in poorly differentiated cases. MET BISH positivity was an independent prognostic factor in nonsquamous NSCLCs.

Frequent ALK rearrangement and TTF-1/p63 co-expression in lung adenocarcinoma with signet-ring cell component

Primary adenocarcinoma with signet-ring cell component (Ad-SRCC) of the lung has been well characterized clinicopathologically and histologically, but their genetics has rarely been investigated. A recent report suggesting an association between Ad-SRCC and EML4-ALK fusion prompted us to undertake a histological, immunohistochemical, and molecular analysis of 10 cases of primary Ad-SRCC identified out of 699 lung adenocarcinomas (1.4%). Most of the Ad-SRCCs showed characteristic architectural as well as cytological features including cohesive clustering of signet-ring cells, a solid/acinar growth pattern, and alveolar filling at the tumor periphery. Diffuse co-expression of TTF-1 and p63 was observed in half of the Ad-SRCCs, and this immunoprofile has not been recognized previously. Four Ad-SRCCs (40%) harbored ALK translocations detected by reverse-transcriptase polymerase chain reaction, fluorescence in situ hybridization, and immunohistochemistry. One new EML4-ALK fusion variant was identified. One ALK-rearranged tumor showed focal squamous differentiation. None of the present Ad-SRCCs had EGFR or KRAS mutations, regardless of ALK status. This study successfully utilized tumor histology alone to identify a subset of adenocarcinomas showing a high rate of ALK translocation. The characteristic histology, immunoprofile, frequent ALK translocation, and total lack of EGFR or KRAS mutations, may suggest that Ad-SRCC forms a histologically/molecularly coherent subgroup of adenocarcinoma.

Epidermal Growth Factor Receptor Mutation Detection Using High-Resolution Melting Analysis Predicts Outcomes in Patients with Advanced Non–Small Cell Lung Cancer Treated with Gefitinib

Purpose: Epidermal growth factor receptor (EGFR) mutations, especially deletional mutations in exon 19 (DEL) and L858R, predict gefitinib sensitivity in patients with non–small cell lung cancer (NSCLC). In this study, we validated EGFR mutation detection using high-resolution melting analysis (HRMA) and evaluated the associations between EGFR mutations and clinical outcomes in advanced NSCLC patients treated with gefitinib on a larger scale. Experimental Design: The presence of DEL or L858R was evaluated using HRMA and paraffin-embedded tissues and/or cytologic slides from 212 patients. In 66 patients, the results were compared with direct sequencing data. Results: HRMA using formalin-fixed tissues had a 92% sensitivity and a 100% specificity. The analysis was successfully completed in 207 patients, and DEL or L858R mutations were detected in 85 (41%) patients. The response rate (78% versus 8%), time-to-progression (median, 9.2 versus 1.6 months), and overall survival (median, 21.7 versus 8.7 months) were significantly better in patients with EGFR mutations (P < 0.001). Even among the 34 patients with stable diseases, the time-to-progression was significantly longer in patients with EGFR mutations. Patients with DEL (n = 49) tended to have better outcomes than those with L858R (n = 36); the response rates were 86% and 67%, respectively (P = 0.037), and the median time-to-progression was 10.5 and 7.4 months, respectively (P = 0.11). Conclusions: HRMA is a precise method for detecting DEL and L858R mutations and is useful for predicting clinical outcomes in patients with advanced NSCLC treated with gefitinib.

Correlation Between Docetaxel Clearance and Estimated Cytochrome P450 Activity by Urinary Metabolite of Exogenous Cortisol

PURPOSE There is no simple and practical method for the estimation of the interpatient variability of cytochrome P450 (CYP3A4) enzyme activity. Cortisol is metabolized by this enzyme and excreted as 6-beta-hydroxycortisol (6beta-OHF) and free-cortisol (FC) in urine, and docetaxel is also metabolized by hepatic CYP3A4 enzyme. We developed a new method for the estimation of CYP3A4 activity by measuring urinary cortisol metabolite after administration of exogenous cortisol. This study was aimed at assessing the predictability of the individual activity of CYP3A4 estimated by this method. PATIENTS AND METHODS Thirty patients with advanced non-small-cell lung cancer were entered onto this study. Hydrocortisone 300 mg was administered intravenously, and urinary 6beta-OHF and FC were measured. More than 2 days later, 60 mg/m(2) of docetaxel was administered intravenously with pharmacokinetic sampling. The correlation between docetaxel pharmacokinetics and estimated interpatient variability of CYP3A4 activity with the application of our method was assessed. RESULTS After cortisol administration, the total amount of 24-hour urinary 6beta-OHF (T6beta-OHF) increased about 60-fold compared with pretreatment levels, averaging 12,273 +/- 4,076 microg/d (mean +/- SD). Docetaxel clearance (CL) and area under the concentration-time curve averaged 24.5 +/- 6.4 L/h/m(2) and 2.66 +/- 0.91 mg/L 8729. h, respectively. An excellent correlation between docetaxel CL and T6beta-OHF was observed (r =.867). In multivariate analysis, T6beta-OHF (P <.001), alpha-1-acid glycoprotein (P <.004), AST (P =.007), and age (P =. 022) significantly correlated with docetaxel CL. CONCLUSION The interpatient variability of CYP3A4 activity and docetaxel CL could be predicted by measuring T6beta-OHF after cortisol administration.

Emerging ethnic differences in lung cancer therapy

Although global clinical trials for lung cancer can enable the development of new agents efficiently, whether the results of clinical trials performed in one population can be fully extrapolated to another population remains questionable. A comparison of phase III trials for the same drug combinations against lung cancer in different countries shows a great diversity in haematological toxicity. One possible reason for this diversity may be that different ethnic populations may have different physiological capacities for white blood cell production and maturation. In addition, polymorphisms in the promoter and coding regions of drug-metabolising enzymes (e.g., CYP3A4 and UGT1A1) or in transporters (e.g., ABCB1) may vary among different ethnic populations. For example, epidermal growth factor receptor (EGFR) inhibitors are more effective in Asian patients than in patients of other ethnicities, a characteristic that parallels the incidence of EGFR-activating mutations. Interstitial lung disease associated with the administration of gefitinib is also more common among Japanese patients than among patients of other ethnicities. Although research into these differences has just begun, these studies suggest that possible pharmacogenomic and tumour genetic differences associated with individual responses to anticancer agents should be carefully considered when conducting global clinical trials.