Akihiro Nishiyama

Rebiopsy of non-small cell lung cancer patients with acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitor: Comparison between T790M mutation-positive and mutation-negative populations.

The secondary epidermal growth factor receptor (EGFR) mutation Thr790Met (T790M) accounts for approximately half of acquired resistances to EGFR‐tyrosine kinase inhibitor (TKI). Recent reports have demonstrated that the emergence of T790M predicts a favorable prognosis and indolent progression. However, rebiopsy to confirm T790M status can be challenging due to limited tissue availability and procedural feasibility, and little is known regarding the differences among patients with or without T790M mutation.

Erlotinib after gefitinib failure in relapsed non-small cell lung cancer: Clinical benefit with optimal patient selection

BACKGROUND Recent reports have suggested that erlotinib therapy after gefitinib failure requires optimal patient selection to obtain clinical benefits in relapsed non-small cell lung cancer (NSCLC). However, insufficient evidence exists to determine which clinical factors best identify patients who benefit from erlotinib therapy. METHODS One hundred twenty-five patients with relapsed NSCLC who had received erlotinib therapy after gefitinib failure were retrospectively evaluated between January 2008 and May 2009. RESULTS The response rate (RR), disease control rate (DCR), and median progression-free survival (PFS) for all patients were 9% (95% confidence interval [CI], 5-15%), 44% (95% CI, 35-53%), and 2.0 months (95% CI, 1.4-2.5 months), respectively. The median survival time was estimated to be 11.8 months (95% CI, 6.4-16.0 months). Using multivariate analysis, good performance status (PS), EGFR mutation-positive status, and benefit from prior gefitinib therapy were identified as significant predictive factors for disease control. Using a proportional hazards model, benefit from prior gefitinib therapy, good PS, and insertion of cytotoxic chemotherapies between gefitinib and erlotinib therapies emerged as significant predictive factors for longer PFS. Thirty-two patients with concomitant PS 0/1, benefit from prior gefitinib therapy, and insertion of cytotoxic chemotherapies between gefitinib and erlotinib therapies benefitted more from erlotinib therapy: RR, 25% (95% CI, 12-43%); DCR, 72% (95% CI, 53-86%); and median PFS, 3.4 months (95% CI, 2.4-4.9 months). CONCLUSIONS Higher efficacy of erlotinib after gefitinib failure can be achieved with proper patient selection criteria, including good PS, benefit from prior gefitinib therapy, and insertion of cytotoxic chemotherapies between gefitinib and erlotinib therapies.

Spatiotemporal T790M Heterogeneity in Individual Patients with EGFR-Mutant Non–Small-Cell Lung Cancer after Acquired Resistance to EGFR-TKI

Introduction: Epidermal growth factor receptor (EGFR) mutation T790M accounts for approximately half of acquired resistances to EGFR-tyrosine kinase inhibitor (TKI). Because T790M is mediated by TKI exposure, its penetration and “on–off” may affect T790M status. Methods: We retrospectively reviewed T790M status and clinical course of patients who had undergone multiple rebiopsies after acquired resistance to EGFR-TKI. Results: Of 145 patients with EGFR-mutant NSCLC receiving rebiopsy after acquired resistance, 30 underwent multiple site rebiopsies, and 24 received repeated rebiopsies at the same lesion. In 22 patients who underwent rebiopsies from both central nervous system (CNS; 20 cerebrospinal fluids [CSF] and 2 brain tumoral tissues) and thoracic lesions (7 lung tissues, 14 pleural effusions, and 1 lymph node), 12 were thoracic-T790M-positive. Of these 12 patients, 10 were CNS-T790M-negative, despite exhibiting thoracic-T790M-positive. All 10 thoracic-T790M-negatives were CNS-T790M-negative. Three patients revealed a spatial heterogeneous T790M status among their thoracic lesions. In 24 patients receiving repeated rebiopsies at the same lesion (12 lung tissues, 6 CSFs, and 6 pleural effusions), T790M status of lung lesions varied in five patients after TKI-free interval. In all five patients whose T790M status changed from positive to negative, EGFR-TKI rechallenge was effective. In three of these five patients, after further TKI exposure, T790M status changed from negative to positive again. There was also a patient whose CSF T790M status changed from negative to positive after high-dose erlotinib therapy. Conclusions: T790M status in an individual patient can be spatiotemporally heterogeneous because of selective pressure from EGFR-TKI.

Complex Mutations in the Epidermal Growth Factor Receptor Gene in Non-small Cell Lung Cancer

Introduction: Mutation of the epidermal growth factor receptor (EGFR) gene can predict the efficacy of EGFR-tyrosine kinase inhibitors. Different mutations have been shown to co-occur in a single tumor. However, the frequency of these so-called “complex mutations” and the efficacy of gefitinib in treating patients with these mutations are unclear. Methods: We investigated the frequency of complex mutations in 783 patients with non-small cell lung cancer seen at our institutes between April 2006 and May 2009. Mutational analysis was performed using the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method. Gefitinib efficacy was evaluated in patients found to have complex mutations. Results: EGFR mutations were detected in 318 (41%) patients, with 21 (6.6%) of these individuals having complex mutations. Sixteen of these 21 patients received gefitinib. The response rate (RR) was 67% (95% confidence interval [CI], 35–90%) and median progression-free survival was 12.2 months (95% CI, 1.3 months to undeterminable). Analysis of RR according to mutation type revealed that patients with deletional mutation in exon 19 (Del-19) and a point mutation in exon 21 (L858R) had a better RR (86%, 6 of 7) than those with other complex mutation patterns such as a point mutation in exon 18 (G719S) + L858R (40%, 2 of 5) (p = 0.2222). The median progression-free survival was also longer in these patients (16.5 months; 95% CI, 1.1 months to undeterminable versus 3.8 months; 95% CI, 0.7–10.0 months) (p = 0.0459). Conclusions: Complex EGFR mutations are not rare. Gefitinib has different efficacy according to the type of complex EGFR mutations. Patients with Del-19 and L858R mutations may benefit more from gefitinib than other types of complex mutations.

How Sensitive Are Epidermal Growth Factor Receptor–Tyrosine Kinase Inhibitors for Squamous Cell Carcinoma of the Lung Harboring EGFR Gene–Sensitive Mutations?

Introduction: Epidermal growth factor receptor (EGFR) mutations are found mostly in adenocarcinoma, and rarely in squamous cell carcinoma (SQC). Little is known about SQC harboring EGFR mutations. Methods: Between April 2006 and October 2010, we investigated the incidence of EGFR activating mutations in SQC of the lung using the peptide nucleic acid-locked nucleic acid polymerase chain reaction clamp method. The efficacy of EGFR-tyrosine kinase inhibitors (TKIs) was retrospectively evaluated in patients with EGFR-mutated SQC. Further pathologic analyses were performed using immunohistochemistry. Results: Thirty-three of 249 patients with SQC (13.3%) had EGFR mutations, including exon 19 deletion (19 of 33 patients, 58%), L858R point mutation in exon 21 (12 of 33, 36%), and G719S point mutation in exon 18 (2 of 33, 6%). Twenty of these 33 patients received EGFR-TKI therapy, and five of these 20 responded to EGFR-TKIs with a response rate of 25.0% (95% confidence interval [CI], 8.7%–49.1%). The patients’ median progression-free survival and median overall survival were 1.4 months (95% CI, 0.7–5.8 months) and 14.6 months (95% CI, 2.9–undeterminable months), respectively. Approximately one third of the EGFR-mutated SQC patients achieved progression-free survival for longer than 6 months. Some of these patients had high carcinoembryonic antigen levels or a history of never smoking, or were positive for thyroid transcription factor-1. Conclusions: Although EGFR-TKIs seem to be generally less effective in EGFR-mutated SQC than in EGFR-mutated adenocarcinoma, some EGFR-mutated SQC patients can obtain clinical benefit from EGFR-TKIs. To better identify these patients, not only EGFR mutation status, but also clinical factors and pathologic findings should be taken into consideration.

Desire for Information and Involvement in Treatment Decisions: Lung Cancer Patients' Preferences and Their Physicians' Perceptions: Results from Okayama Lung Cancer Study Group Trial 0705

Introduction: This study explores patient preferences for involvement in lung cancer treatment decisions and the extent of concordance between the views of patients and physicians on decisional roles. The impact of demographic and psychosocial characteristics on the decisional role of patients is also examined. Methods: Patients with relapsed non-small cell lung cancer who were candidates for a phase II trial of erlotinib monotherapy were recruited. Patients were interviewed after they had learned of their relapse and the treatment decision had been made but before pharmacologic intervention. Results: Most of the 28 participants were married, had a smoking history, and were well educated. They reported moderate levels of depression and anxiety. Initially, 14% of the patients reported a preference for active decision making; later, 29% believed that the primary responsibility for the treatment decision had been theirs. Only 54% of the patients agreed with the physicians assessment of how the treatment decision was made (&kgr; = 0.31; test of symmetry, p = 0.23). The depression score was significantly associated with a patients preferred level of control (p < 0.01). Conclusions: The limited concordance between patient preference and perception and between patient and physician perceptions regarding how the treatment decision was made suggests that physicians should more accurately identify patient preferences by directly asking patients at the beginning of each clinical encounter.

A Phase II Study of Pemetrexed in Chemotherapy-naïve Elderly Patients Aged ≥75 years with Advanced Non-squamous Non-small-cell Lung Cancer (HANSHIN Oncology Group 003)

OBJECTIVE Pemetrexed has relatively mild toxicity and possibly can be administered long term to patients with non-small-cell lung cancer. We conducted a Phase II trial to evaluate the efficacy and safety of pemetrexed in chemotherapy-naïve elderly patients with advanced non-squamous non-small-cell lung cancer. METHODS In this multicenter Phase II trial, we recruited elderly patients with non-squamous non-small-cell lung cancer. Patients with previously untreated Stage IIIB or IV non-squamous non-small-cell lung cancer, ≥75 years, Eastern Cooperative Oncology Group performance status 0-1 and adequate organ functions were eligible. Patients received pemetrexed (500 mg/m(2)) intravenously on Day 1 every 3 weeks until disease progression. The primary endpoint was objective response rate. RESULTS Forty-seven patients were enrolled from August 2009 to July 2011, and 46 patients were eligible. The median age was 79 years (range 75-91 years), 57% were males, 37% had never smoked, 87% had adenocarcinoma, 74% had Stage IV and 33% had epidermal growth factor receptor tyrosine kinase-activating mutation. The median number of cycles was 4 (1-20). The objective response rate was 13.3% (95% confidence interval; 5.1-26.8%), the disease control rate was 66.7% (95% confidence interval 51.0-80.0%), the median progression-free survival was 4.9 months (95% confidence interval 3.0-6.1 months) and the median overall survival was 18.2 months (95% confidence interval 13.2-23.5 months). One Grade 5 infection (pneumonia) was observed. CONCLUSIONS This study did not meet the primary endpoint. Pemetrexed monotherapy is not recommended in chemotherapy-naïve elderly patients aged ≥75 years with advanced non-squamous non-small-cell lung cancer.

Interstitial lung disease induced by alectinib (CH5424802/RO5424802).

A 75-year-old woman with anaplastic lymphoma kinase (ALK)-rearranged Stage IV lung adenocarcinoma was administered the selective anaplastic lymphoma kinase inhibitor, alectinib, as a third-line treatment in a Phase 1-2 study. On the 102nd day, chest computed tomography showed diffuse ground glass opacities. Laboratory data revealed high serum levels of KL-6, SP-D and lactate dehydrogenase without any clinical symptoms. There was no evidence of infection. Marked lymphocytosis was seen in bronchoalveolar lavage fluid analysis, and transbronchial lung biopsy showed mild thickening of alveolar septa and lymphocyte infiltration. Interstitial lung disease was judged to be related to alectinib based on improvements in imaging findings and serum biomarkers after discontinuation of alectinib. To our knowledge, this is the first reported case of alectinib-induced interstitial lung disease. Alectinib is a promising drug for ALK-rearranged non-small cell lung cancer. Clinical trials of this selective anaplastic lymphoma kinase inhibitor will facilitate the meticulous elucidation of its long-term safety profile.

Identifying the Cause of the "Saturation Gap": Two Cases of Dapsone-induced Methemoglobinemia

Diaphenylsulfone (DDS: Dapsone) is used for Pneumocystis pneumonia (PCP) prophylaxis, and methemoglobinemia has rarely been reported as a side effect of DDS. We herein report two cases of DDS-related methemoglobinemia in an 81-year-old man with organizing pneumonia and an 84-year-old woman with eosinophilic pneumonia under treatment with prednisolone. Both patients initially received trimethoprim/sulfamethoxazole for PCP prophylaxis and were switched to DDS due to side effects and subsequently exhibited a clinically unexplainable decrease in SpO2. Methemoglobinemia was diagnosed based on the findings of arterial blood gas analyses. In both cases, the methemoglobinemia improved after discontinuing DDS.

Clinical characteristics of severe community-acquired pneumonia among younger patients: An analysis of 18 years at a community hospital

Unlike elderly patients with community-acquired pneumonia whose outcomes are markedly affected by their background characteristics, it appears that the severity of the infection itself contributes to outcomes in younger patients with community-acquired pneumonia. In order to identify clinical characteristics of severe community-acquired pneumonia in younger patients under 60 years old, among such cases prospectively collected at our hospital over a period of 18 years, those meeting the criteria for severe community-acquired pneumonia, as defined in the Infectious Diseases Society of America/American Thoracic Society Guidelines for community-acquired pneumonia, were retrospectively examined and compared to elderly patients with severe community-acquired pneumonia. Younger patients with severe pneumonia accounted for 12.9% of younger hospitalized patients. Although the incidence of severe pneumonia in younger patients was lower than that in elderly patients, its severity may be underestimated by severity assessment based on the conventional guidelines. Thus, attention is required. While Streptococcus pneumoniae and Legionella species were important causative pathogens, atypical pathogens and viruses were also frequently detected. There were only 11 deaths over a period of 18 years. Based on multivariate analysis, the risk factors for aggravation of community-acquired pneumonia among younger patients were age 50 years or older, diabetes mellitus, chronic liver disease, and Legionella pneumonia. Although the mortality rate from community-acquired pneumonia is extremely low in previously healthy younger patients, outcomes might be poor for patients with underlying diseases and those with rapid progression. Multimodal treatments including respiratory management may be appropriate.