RBM17 Expression Is Associated With the Efficacy of ICI Monotherapy in NSCLC With Low PD-L1 Expression.

BACKGROUND/AIM: Immune checkpoint inhibitors (ICIs) are currently a standard treatment tool for non-small cell lung cancer (NSCLC). RNA-binding motif protein 17 (RBM17), a splicing factor, is frequently over-expressed in NSCLC, but little is known about the role of RBM17 in the efficacy of ICIs for NSCLC. Thus, we investigated the correlation between RBM17 expression and ICI efficacy in NSCLC. PATIENTS AND METHODS: Biopsy or surgical specimens were collected from patients with advanced or recurrent NSCLC who received ICI monotherapy or chemo-immunotherapy in a first-line setting. RBM17 expression was examined using immunohistochemistry. The correlation between the efficacy of ICI monotherapy or chemo-immunotherapy and RBM17 expression was evaluated. RESULTS: Among the 218 cases, 115 (52.8%) cases were positive for RBM17 expression. RBM17 expression was not associated with the objective response rate (ORR) or progression-free survival (PFS) in either of the ICI monotherapy or chemo-immunotherapy groups. However, among those with a low PD-L1 expression level (PD-L1 <50%; n=86), RBM17 expression was significantly associated with a better ORR (p=0.045) and a better PFS (p<0.001) in the ICI monotherapy group, and was significantly associated with a poor ORR in the chemo-immunotherapy group (p=0.041). CONCLUSION: RBM17 might be a useful predictive marker for a higher efficacy of ICI monotherapy in NSCLC patients with a low PD-L1 expression level.

Clinical significance of KL-6 in immune-checkpoint inhibitor treatment for non-small cell lung cancer.

PURPOSE: Krebs von den Lungen-6 (KL-6) functions as a tumor marker, as well as a diagnostic tool for interstitial pneumonia (IP). However, the significance of KL-6 in the immune-checkpoint inhibitor (ICI) treatment of non-small cell lung cancer (NSCLC), especially in patients without IP, is unknown. METHODS: This multicenter, retrospective study, which included patients with advanced NSCLC who received ICI therapy, analyzed the association between serum KL-6 values and ICI efficacy and the association between serum KL-6 values and ICI-induced interstitial lung disease (ILD) occurrence, focusing primarily on patients without IP. RESULTS: In total, 322 patients had available KL-6 values before ICI therapy. Among 202 patients without IP who received ICI monotherapy, the high-KL-6 group (≥ 500 U/mL) showed significantly shorter progression-free survival (PFS) and overall survival (OS) than the low-KL-6 group (< 500 U/mL) (median: 2.1 vs. 3.6 months, p = 0.048; median: 9.2 vs. 14.5 months, p = 0.035). There was no significant difference in response rate between the KL-6 high and low groups (19% vs. 29%, p = 0.14). In the multivariate analysis, high KL-6 was a significant predictor of poor PFS (hazard ratio [HR], 1.52; 95% confidence interval [CI] 1.10-2.11, p = 0.012) and OS (HR, 1.51; 95% CI 1.07 - 2.13, p = 0.019) for patients treated with ICI monotherapy. There was no significant difference in the occurrence rate of ILD between the high KL-6 and low KL-6 groups in patients with (20% vs. 15%, p = 1.00) or without IP (12% vs. 12%, p = 1.00). CONCLUSION: In ICI monotherapy for NSCLC without IP, elevated serum KL-6 levels were associated with poorer outcomes.

Vimentin expression correlates with immune checkpoint inhibitor efficacy in non-small cell lung cancer.

BACKGROUND: Although vimentin is often expressed in non-small cell lung cancer (NSCLC), the association between vimentin expression and immune-checkpoint inhibitor (ICI) efficacy remains unclear. METHODS: This retrospective multicenter study enrolled patients with NSCLC who received ICI treatment between December 2015 and July 2020. The authors constructed tissue microarrays and performed immunohistochemical staining with vimentin. They analyzed the relationship between vimentin expression rate and objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: Immunohistochemically evaluable specimens on microarray blocks were available for 397 patients, of whom 343 (86%) were negative (<10%), 30 (8%) were positive (10%-49%), and 24 (6%) were highly positive (≥50%) for vimentin expression. Both rates of programmed death-ligand 1 (PD-L1) tumor proportion score ≥1% and ≥50% were significantly higher in the vimentin-positive group (≥10%) than the vimentin-negative group (<10%) (96% vs. 78%, p = .004; 64% vs. 42%, p = .006, respectively). In patients treated with ICI monotherapy, ORR, PFS, and OS were significantly better in the vimentin-positive group (10%-49%) than in the vimentin-negative group (<10%) (54% vs. 25%, p = .003, median = 7.9 vs. 3.2 months, p = .011; median = 27.0 vs. 13.6 months, p = .015, respectively), whereas there was no significant difference in PFS and OS between the vimentin highly positive group (≥50%) and the vimentin-negative group (<10%) (median = 3.4 vs. 3.2 months, p = .57; median = 7.2 vs. 13.6 months, p = .086, respectively). CONCLUSIONS: Vimentin expression correlated with PD-L1 expression and ICI efficacy. PLAIN LANGUAGE SUMMARY: We constructed tissue microarrays and performed immunohistochemical staining with vimentin on 397 patients with advanced non-small cell lung cancer who were treated with immune-checkpoint inhibitor (ICI). The vimentin-positive group who were treated with ICI monotherapy showed significantly better objective response rate, progression-free survival, and overall survival than the vimentin negative group. The measurement of vimentin expression will aid in determining appropriate immunotherapy strategies.

Influence of Smoking History on the Effectiveness of Immune-checkpoint Inhibitor Therapy for Non-small Cell Lung Cancer: Analysis of Real-world Data.

BACKGROUND/AIM: There is no real-world data in an Asian population to investigate the difference between the outcome of immune-checkpoint inhibitor (ICI) monotherapy and combination therapy for non-small cell lung cancer (NSCLC) based on smoking status. In this study, we investigated the correlation between smoking status and the efficacy of ICI therapy for NSCLC patients. PATIENTS AND METHODS: This multicentre retrospective study enrolled patients with recurrent or metastatic NSCLC who were treated using ICI therapy between December 2015 and July 2020. We analysed the objective response rate (ORR) of patients who received ICI monotherapy or combination therapy, based on smoking status using Fisher's exact test, and progression-free survival (PFS) and overall survival (OS) based on smoking status using the Kaplan-Meier method, the log-rank test, and Cox proportional hazards model. RESULTS: A total of 487 patients were included in the study. In the ICI monotherapy group, non-smokers showed significantly lower ORR and shorter PFS and OS than smokers (10% vs. 26%, p=0.002; median: 1.8 vs. 3.8 months, p<0.001; median: 8.0 vs. 15.4 months, p=0.026). In the ICI combination therapy group, non-smokers showed significantly longer OS than smokers (median: not reached vs. 26.3 months, p=0.045), and there was no significant difference in ORR and PFS between non-smokers and smokers (63% vs. 51%, p=0.43; median: 10.2 vs. 9.2 months, p=0.81). In the multivariate analysis of patients who received ICI combination therapy, the "non-smoker" status was not significantly associated with PFS [hazard ratio (HR)=1.31; 95% confidence interval (CI)=0.70-2.45, p=0.40] and OS (HR=0.40; 95% CI=0.14-1.13, p=0.083). CONCLUSION: Non-smokers showed worse outcomes than smokers with ICI monotherapy, but not with ICI combination therapy.

The Impact of Estrogen Receptor Expression on Mutational Status in the Evolution of Non-Small Cell Lung Cancer.

BACKGROUND: The role of estrogen receptor (ER) status in the carcinogenesis of lung cancer and its impact on prognosis remain unclear. MATERIALS AND METHODS: We previously reported a prospective, multicenter, molecular epidemiology study (Japan Molecular Epidemiology for Lung Cancer Study [JME]). We examined the relationship of ER status with reproductive and hormonal factors, mutational profile, and survival using JME study data. Patients were enrolled between July 2012 and December 2013, with follow-up until November, 2017. RESULTS: Among 441 ever- and 435 never-smokers, ER expression was observed in 46.4% and 53.5%, respectively (P = .022). Hormone use and reproductive history of female patients were not associated with ER status. Mutations in EGFR (P = .003), TP53 (P = .007), and CTNNB1 (P = .027) were significantly associated with ER expression. Multivariate analysis showed that mutations in EGFR (P = .032) and CTNNB1 (P = .026) were significantly associated with ER expression, whereas TP53 mutations exhibited a trend toward significance (P = .059). Relapse-free survival (RFS) was longer in all the patients with ER-positive tumors than those with ER-negative tumors (P = .021). RFS and overall survival were longer (P = .024, P = .011, respectively) in the stage I patients with ER-positive tumors than those with ER-negative tumors. CONCLUSION: ERß expression is positively associated with EGFR mutations and negatively with TP53 and CTNNB1 mutations. ER-positive tumors can be associated with better prognosis of the patients, suggesting that ER expression with coexisting EGFR mutations and wild-type TP53 contribute to the biology of non-small cell lung cancer.

Association of thyroid transcription factor-1 with the efficacy of immune-checkpoint inhibitors in patients with advanced lung adenocarcinoma.

BACKGROUND: We aimed to identify the relationship between thyroid transcription factor-1 (TTF-1) expression of lung adenocarcinoma and the efficacy of immune-checkpoint inhibitor (ICI) therapy. METHODS: This retrospective multicenter study comprised patients with advanced lung adenocarcinoma treated with ICI monotherapy. We collected clinical medical records including data on TTF-1 expression and analyzed the relationship between TTF-1 expression and programmed death-ligand 1 tumor proportion score (PD-L1 TPS), objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). RESULTS: In total, 108 patients with lung adenocarcinoma were analyzed. The rate of TPS ≥1% and ≥50% in patients with positive TTF-1 expression was significantly higher than that in patients with negative TTF-1 expression (88% vs. 60%, p < 0.001; 65% vs. 24%, p < 0.001). The ORR was significantly higher in TTF-1 positive patients than in TTF-1-negative patients (38% vs. 8%, p = 0.003). Among patients with TPS ≥50% and 1%-49%, the ORR in TTF-1 positive and negative patients was 48% (26/54) versus 17% (1/6) (p = 0.21), and 32% (6/19) versus 11% (1/9) (p = 0.37), respectively. The ORR for patients with TPS <1% was 0% in both the TTF-1 negative and positive cases. The median PFS and OS was significantly longer in TTF-1-positive patients than in TTF-1-negative patients (5.4 vs. 1.6 months, p < 0.001; 18.2 vs. 8.0 months, p = 0.041). Multivariate analysis revealed that TTF-1-negative status was an independent unfavorable prognostic factor for PFS. CONCLUSION: Patients with TTF-1-positive status receiving ICI monotherapy showed better outcomes than those with TTF-1-negative lung adenocarcinoma.

Prognostic impact of pretreatment T790M mutation on outcomes for patients with resected, EGFR-mutated, non-small cell lung cancer.

BACKGROUND: Many previous studies have demonstrated that minor-frequency pretreatment T790M mutation (preT790M) could be detected by ultrasensitive methods in a considerable number of treatment-naïve, epidermal growth factor receptor (EGFR)-mutated, non-small cell lung cancer (NSCLC) cases. However, the impact of preT790M in resected cases on prognosis remains unclear. METHODS: We previously reported that preT790M could be detected in 298 (79.9%) of 373 surgically resected, EGFR-mutated NSCLC patients. Therefore, we investigated the impact of preT790M on recurrence-free survival (RFS) and overall survival (OS) in this cohort by multivariate analysis. All patients were enrolled from July 2012 to December 2013, with follow-up until November 30, 2017. RESULTS: The median follow-up time was 48.6 months. Using a cutoff value of the median preT790M allele frequency, the high-preT790M group (n = 151) had significantly shorter RFS (hazard ratio [HR] = 1.51, 95% confidence interval [CI]: 1.01-2.25, P = 0.045) and a tendency for a shorter OS (HR = 1.87, 95% CI: 0.99-3.55, P = 0.055) than the low-preT790M group (n = 222). On multivariate analysis, higher preT790M was independently associated with shorter RFS (high vs low, HR = 1.56, 95% CI: 1.03-2.36, P = 0.035), irrespective of advanced stage, older age, and male sex, and was also associated with shorter OS (high vs low, HR = 2.16, 95% CI: 1.11-4.20, P = 0.024) irrespective of advanced stage, older age, EGFR mutation subtype, and history of adjuvant chemotherapy. CONCLUSIONS: Minor-frequency, especially high-abundance of, preT790M was an independent factor associated with a poor prognosis in patients with surgically resected, EGFR-mutated NSCLC.

Vascular endothelial growth factor receptor 2 expression and immunotherapy efficacy in non-small cell lung cancer.

It is unclear whether tumor vascular endothelial growth factor receptor 2 expression affects the therapeutic efficacy of immune-checkpoint inhibitors and antiangiogenic agents. This retrospective, multicenter study included patients with advanced non-small cell lung cancer who were treated with immune-checkpoint inhibitors. We constructed tissue microarrays and performed immunohistochemistry with an anti-vascular endothelial growth factor receptor 2 antibody. We analyzed immune and tumor cell staining separately in order to determine their correlation with the objective response rate, progression-free survival, and overall survival in patients receiving immune-checkpoint inhibitors. Of 364 patients, 37 (10%) expressed vascular endothelial growth factor receptor 2 in immune cells and 165 (45%) in tumor cells. The objective response rate, progression-free survival, and overall survival were significantly worse in patients treated with immune checkpoint inhibitor monotherapy who expressed vascular endothelial growth factor receptor 2 in immune cells than those who did not (10% vs 30%, p = 0.028; median = 2.2 vs 3.6 months, p = 0.012; median = 7.9 vs 17.0 months, p = 0.049, respectively), while there was no significant difference based on tumor cell expression (24% vs 30%, p = 0.33; median = 3.1 vs 3.5 months, p = 0.55; median = 13.6 vs 16.8 months, p = 0.31). There was no significant difference in overall survival between patients treated with and without antiangiogenic agents in any treatment period based on vascular endothelial growth factor receptor 2 expression. Immune checkpoint inhibitor efficacy was limited in patients expressing vascular endothelial growth factor receptor 2 in immune cells.

A case of squamous cell lung cancer treated with anamorelin in combination with a multidisciplinary collaborative approach for treating cancer cachexia.

Anamorelin (ANA) is approved for treating cancer cachexia (CCX) in Japan. We report the case of a 69-year-old man with stage IVB squamous cell lung cancer complicated by CCX, having a 13.6% weight loss in 6 months. After chemotherapy was initiated, his weight was further reduced. Therefore, we started ANA combined with a treatment approach by a multidisciplinary collaboration, including nutritionists and physical therapists. After initiation of ANA, the body weight, appetite, psoas muscle index, and physical functions rapidly improved during chemotherapy. ANA administration combined with a multidisciplinary collaboration approach can be an effective supportive therapy against CCX during chemotherapy.

A case of renal cell carcinoma with late recurrence in the bilateral hilar lymph nodes twenty years after surgery.

Renal cell carcinoma (RCC) is a common malignancy with a high recurrence rate. However, brain and bilateral hilar lymph node (BHL) relapse is rare. A 65-year-old man with a chief complaint of hemosputum visited the primary care clinic. Computed tomography revealed BHL enlargement. Histopathological examination of biopsy specimens from the left lingular bronchus revealed RCC. This finding was similar to that of a left nephrectomy specimen of RCC observed 20 years ago. If patients have a medical history of RCC, physicians should consider the possibility of RCC recurrence, regardless of the number of years relapsed postoperatively.

Acromegaly Initially Presenting with Severe Infectious Diseases: A Case Report.

A 39-year-old man presented with worsening fever, cough, and fatigue. He was immediately admitted to the intensive care unit (ICU) and was found to have sepsis, septic pulmonary embolism, right empyema, liver abscess, pyelonephritis, and a prostate abscess, with background diabetes mellitus. While receiving treatment, an ICU nurse noticed that the patient's toe tips were too large to fit the clamp device of pulse oximeters. Thus, we re-examined the patient and confirmed that he had clinical features indicative of acromegaly including bulging eyebrows, enlarged nose and lips, large feet, and prognathism. He and his family had not noticed these features except for his enlarged feet. We evaluated the patient further for acromegaly, and a pituitary mass was detected via contrast-enhanced head magnetic resonance imaging. Whole-body computed tomography also revealed thickened heel pads, cauliflower deformity, frontal sinus enlargement, sella turcica enlargement, and mandibular malocclusion. A 75 g oral glucose tolerance test was performed to investigate abnormal secretion of growth hormone (GH), and the results revealed a paradoxical increase in GH levels. The patient was then diagnosed with acromegaly according to the clinical guidance of the Japan Endocrine Society. Acromegaly develops slowly; thus, to improve patients' prognoses, physicians including internists, family physicians, and endocrinologists should include acromegaly in their differential when signs are apparent.

SP142 evaluation contributes to the prediction of immune checkpoint inhibitor efficacy in non-small cell lung cancer with high PD-L1 expression assessed by 22C3.

Background: It remains unclear whether assessing programmed death-ligand 1 (PD-L1) expression by SP142 plus 22C3 adds value for predicting the response to immunotherapy in non-small cell lung cancer (NSCLC). Methods: This retrospective multicenter study included patients with advanced NSCLC treated with immune-checkpoint inhibitors. We constructed tissue microarrays (TMAs) and performed immunohistochemical staining with 22C3 and SP142 assays. We denoted the PD-L1 tumor proportion score (TPS) obtained from clinical medical records based on 22C3 staining as "22C3 (C)" and that obtained with 22C3 staining using our TMA as "22C3 (TMA)". SP142 staining was evaluated in both tumor cells and immune cells. We assessed the concordance between each PD-L1 assessment method and analyzed the objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) based on the PD-L1 expression level determined using the 22C3 and SP142 assays. Results: In total, 288 patients were included. Among those with 22C3 (TMA) ≥50%, 60% of patients showed SP142 TC3 or IC3; among patients with 22C3 (C) <1%, 9% and 18% exhibited 22C3 (TMA) ≥1% and SP142 TC1/2/3 or IC1/2/3, respectively. Among patients with 22C3 (C) ≥50% treated with immune-checkpoint inhibitor monotherapy, the SP142 TC1/2/3 or IC1/2/3 group showed significantly better ORR, PFS and OS than the SP142 TC0 and IC0 group (54% vs. 29%, P=0.040, median =11.0 vs. 3.2 months, P=0.002, median =27.9 vs. 12.6 months, P=0.030, respectively). Multivariate analysis revealed that SP142 TC0 and IC0 was an independent unfavorable prognostic factor for PFS and OS in patients with 22C3 (C) ≥50% treated with immune-checkpoint inhibitor monotherapy. For those with 22C3 (C) ≥50% and SP142 TC0 and IC0, immune-checkpoint inhibitor concurrent with chemotherapy tended to result in a longer PFS and OS than immune-checkpoint inhibitor monotherapy (median =13.7 vs. 2.3 months, P=0.054, median = not estimable vs. 12.0 months, P=0.064, respectively). Conclusions: SP142 evaluation contributes to the prediction of immune-checkpoint inhibitor efficacy in NSCLC with high PD-L1 expression assessed by 22C3.

Can smoking duration alone replace pack-years to predict the risk of smoking-related oncogenic mutations in non-small cell lung cancer? A cross-sectional study in Japan.

OBJECTIVE: To investigate whether smoking duration alone can replace pack-years to predict the risk of oncogenic mutations in non-small cell lung cancer (NSCLC). DESIGN: A cross-sectional study using the baseline dataset from the Japan Molecular Epidemiology for Lung Cancer Study. SETTING: Forty-three medical institutions nationwide in Japan. PARTICIPANTS: From July 2012 to December 2013, 957 patients with newly diagnosed stage I-IIIB NSCLC who underwent surgery were enrolled, and molecular analyses were performed on 876 samples (from 441 ever-smokers and 435 never-smokers). MAIN OUTCOMES MEASURED: We calculated the area under the receiver operating characteristic curve (AUC) values using logistic regression to compare between the predictive values of smoking duration and pack-years for mutational frequencies in the v-Ki-ras2 Kirsten rat sarcoma (KRAS), tumour suppressor p53 (TP53), and epidermal growth factor receptor (EGFR) genes and for cytosine-to-adenine base substitution (C>A). RESULTS: For predicting KRAS mutations, the AUC values for smoking duration and pack-years were 0.746 (95% CI 0.682 to 0.800) and 0.759 (95% CI 0.700 to 0.810), respectively (p=0.058). For predicting KRAS mutations in smokers, the AUC values for smoking duration and pack-years were 0.772 (95% CI 0.697 to 0.833) and 0.787 (95% CI 0.714 to 0.845), respectively (p=0.036). There were no significant differences between the AUC values for smoking duration and pack-years in terms of predicting TP53 and EGFR mutations and C>A. Pack-years was a significantly better predictor of KRAS mutations than smoking duration. CONCLUSION: Smoking duration was not significantly different from pack-years in predicting the likelihood of smoking-related gene mutations. Given the recall bias in obtaining smoking information, smoking duration alone should be considered for further investigation as a simpler alternative to pack-years.

Differences in molecular epidemiology of lung cancer among ethnicities (Asian vs. Caucasian).

BACKGROUND: Differences in carcinogenesis and therapeutic efficacy according to ethnicity have been reported for lung cancer, and understanding differences in genetic mutation profiles among ethnicities is important for interpreting the results of clinical trials, preventing carcinogenesis, and individualizing treatment. However, no studies have focused on differences in mutation profiles among different ethnicities using large-scale genomic analysis data with detailed information on smoking history, the main cause of lung cancer. METHODS: To clarify the differences in genetic mutation profiles between Caucasian and Japanese subjects, we compared data from The Cancer Genome Atlas, which mainly included Caucasians, with results from the Japan Molecular Epidemiology for lung cancer study, which is an epidemiological study only involving Japanese subjects. We divided the participants into four groups according to smoking status and performed comparative analysis by tissue type (lung adenocarcinoma and squamous cell lung cancer). RESULTS: In patients with lung adenocarcinoma, the frequency of EGFR mutations was lower in Caucasian subjects than in Japanese subjects (14.6% vs. 51.1%), whereas the frequencies of mutations in other genes, namely KRAS (32.9% vs. 9.3%), TP53 (45.2% vs. 20.7%), BRAF (9.6% vs. 1.3%), PIK3CA (5.9% vs. 2.6%), KEAP1 (17.8% vs. 0.5%), NF1 (10.9% vs. 0.5%), STK11 (17.8% vs. 0.7%), RBM10 (8.7% vs. 0.1%), and MET (7.8% vs. 0.1%), were higher in Caucasian subjects. Among patients with squamous cell carcinoma, TP53 (81.2% vs. 49.1%), PIK3CA (14.5% vs. 6.8%), KEAP1 (12.7% vs. 0.9%), and NFE2L2 mutations (15.8% vs. 13.6%) were more common in Caucasian subjects. CONCLUSIONS: Ethnicity is an important and complex characteristic that must be recognized and considered, even in the era of precision medicine. We should collaborate to share data for different ethnicities and incorporate them into clinical practice and the design of global clinical studies. Carefully designed molecular epidemiological studies focusing on ethnic differences are warranted.

Impact of somatic mutations on prognosis in resected non-small-cell lung cancer: The Japan Molecular Epidemiology for lung cancer study.

BACKGROUND: To report the follow up data and clinical outcomes of the JME study (UMIN 000008177), a prospective, multicenter, molecular epidemiology examination of 876 surgically resected non-small-cell lung cancer (NSCLC) cases, and the impact of somatic mutations (72 cancer-associated genes) on recurrence-free survival (RFS) and overall survival (OS). METHODS: Patients were enrolled between July 2012 and December 2013, with follow up to 30th November 2017. A Cox proportional hazards model was used to assess the impact of gene mutations on RFS and OS, considering sex, smoking history, age, stage, histology, EGFR, KRAS, TP53, and number of coexisting mutations. RESULTS: Of 876 patients, 172 had ≥2 somatic mutations. Median follow-up was 48.4 months. On multivariate analysis, number of coexisting mutations (≥2 vs 0 or 1, HR = 2.012, 95% CI: 1.488-2.695), age (≥70 vs <70 years, HR = 1.583, 95% CI: 1.229-2.049), gender (male vs female, HR = 1.503, 95% CI: 1.045-2.170) and pathological stage (II vs I, HR = 3.386, 95% CI: 2.447-4.646; ≥III vs I, HR = 6.307, 95% CI: 4.680-8.476) were significantly associated with RFS, while EGFR mutation (yes vs no, HR = 0.482, 95% CI: 0.309-0.736), number of coexisting mutations (≥2 vs 0 or 1, HR = 1.695, 95% CI: 1.143-2.467), age (≥70 vs <70 years, HR = 1.932, 95% CI: 1.385-2.726), and pathological stage (II vs I, HR = 2.209, 95% CI: 1.431-3.347; ≥III vs I, HR = 5.286, 95% CI: 3.682-7.566) were also significant for OS. CONCLUSION: A smaller number of coexisting mutations, earlier stage, and younger age were associated with longer RFS and OS, while EGFR mutations were significantly associated with improved OS.

A Case of Dapsone-induced Mild Methemoglobinemia with Dyspnea and Cyanosis.

Dear Editor, Dapsone is a dual-function drug with antimicrobial and antiprotozoal effects and anti-inflammatory features (1). In dermatology, it is a first choice for conditions such as leprosy, IgA pemphigus, dermatitis herpetiformis, and linear IgA bullous dermatosis, or an adjunctive treatment for, e.g. bullous pemphigoid (BP) and pemphigus vulgaris (1). However, dapsone is associated with some adverse effects, including methemoglobinemia (1). Methemoglobin (MetHb) concentrations of less than 15% usually cause no symptoms in patients with normal hemoglobin concentrations (2). Herein, we report the case of a patient with BP who developed dyspnea because of dapsone-induced methemoglobinemia that was as mild as 4.7%. A 93-year-old man was diagnosed with BP based on skin manifestations (Figure 1, a and b), histopathological findings (Figure 1, c and d), and anti-BP180 NC16A antibody titer determined by chemiluminescence enzyme immunoassay (279 U/mL) 3 years earlier. His comorbidities included diabetes mellitus, chronic heart failure, right pleural effusion, and brain infarction. The patient had been successfully treated with oral prednisolone, so the steroid was tapered to 4 mg/day. The blisters recurred, however, and new ones kept developing even though the prednisolone was increased to 25 mg/day. Dapsone (75 mg/day) was begun as adjunctive treatment, and new blister formation ceased. At one week from dapsone initiation, the patient developed dyspnea, and his oxygen saturation as measured by pulse oximetry decreased to 88% on room air. At presentation, his blood pressure was 118/78 mmHg, the heart rate was 95 beats/minute, and axillary temperature was 36.3 °C. Neurological examination and consciousness findings remained unchanged compared with findings before dyspnea onset. Chest examination showed normal breath and heart sounds, but lip and peripheral cyanosis was present. Blood tests revealed a white blood cell count of 12,920/µl; red blood cells, 370×104/µl; hemoglobin, 11.7 g/dl; and CMV antigenemia (or C7-HRP), negative. Chest CT and echocardiography indicated no remarkable change compared with imaging from one year earlier. Arterial blood gas analysis showed a pH of 7.454, PaO2 63.1 mmHg, PaCO2 35.4 mmHg, HCO3- 24.3 mmol/L, SaO2 92.4%, and MetHb of 4.7%. These findings indicated a saturation gap (difference between SpO2 and SaO2) induced by MetHb. Upon cessation of dapsone, MetHb levels and SpO2 returned to normal and the dyspnea resolved, implicating dapsone in the methemoglobinemia (Figure 1, e). Differential diagnoses were pulmonary disease, heart disease, neuromuscular disease, sepsis, and drug intoxication. These possibilities were ruled out by the physical examination, drug history, vital signs, blood tests, and chest CT and echocardiography. In normal individuals, MetHb levels are less than 1% (2). Healthy patients with normal hemoglobin concentrations develop cyanosis at MetHb level of 15-20%, dyspnea at 20-50%, and coma at 50-70%, and die at more than 70% (2). However, patients with hematologic disease, acidosis, or cardiopulmonary diseases, for example, present with symptoms even with MetHb levels less than 15% (2,3). We inferred that our patient presented with dyspnea even under mild methemoglobinemia because he had anemia, chronic heart failure, and right pleural effusion. The occurrence of dapsone-induced methemoglobinemia with obvious symptoms is rare (1,4). Clinicians should be aware that methemoglobinemia symptoms are influenced not only by MetHb concentrations but also by comorbidities.

Predictive impact of low-frequency pretreatment T790M mutation in patients with EGFR-mutated non-small cell lung cancer treated with EGFR tyrosine kinase inhibitors.

OBJECTIVES: Low-frequency epidermal growth factor receptor (EGFR) T790M mutation could be detected by ultrasensitive methods in EGFR tyrosine kinase inhibitor (TKI)-naïve non-small cell lung cancer (NSCLC). However, the impact of pretreatment T790M (preT790M) on the efficacy of EGFR-TKIs and on resistance remains unclear. MATERIALS AND METHODS: Two independent cohorts consisting of advanced EGFR-mutated NSCLC patients treated with first-line EGFR-TKIs, a derivation cohort that started treatment between August 2013 and July 2016 (cohort A, n = 44) and a validation cohort between August 2016 and December 2017 (cohort B, n = 22), were examined in this study. Among these, 28 patients underwent re-biopsy at disease progression. DNAs from pretreatment tumor biopsy samples and re-biopsy samples were assessed to detect T790M by the Cobas EGFR Mutation Test v2 (Cobas) and for quantitating T790M by droplet digital polymerase chain reaction (ddPCR). RESULTS: Detection rates of preT790M were 40.9% (18/44) in cohort A and 45.5% (10/22) in cohort B by ddPCR, and none by Cobas. A cutoff value of 0.3% for dividing into high- vs. low-preT790M allele frequency was determined by receiver operating characteristic curve analysis in cohort A. Progression-free survival (PFS) was significantly shorter in the high- preT790M group (n = 12) than in the low-preT790M (n = 6) and negative (n = 26) groups (combined low-preT790M) (median: 6.9 vs. 13.8 months, P =  0.00073). These observations were validated in cohort B [median: 6.2 (n = 5) vs. 15.3 months (n = 17), P =  0.0029]. In 28 paired biopsies, Cobas detected post-progression T790M in 60% (3/5) of the high-preT790M, in 57% (4/7) of the low-preT790M, and in 56% (9/16) of the negative-preT790M groups. CONCLUSION: EGFR-mutated NSCLC with high preT790M had significantly shorter PFS on EGFR-TKIs. However, preT790M abundance may not necessarily confer post-TKI T790M resistance.

Efficacy and safety of ultrasound (US) guided percutaneous needle biopsy for peripheral lung or pleural lesion: comparison with computed tomography (CT) guided needle biopsy.

BACKGROUND: Ultrasound (US)-guided percutaneous needle biopsy is a useful diagnostic technique with short examination time and real-time monitoring at the bedside. However, there are only a few studies that report on thoracic lesions, whereas the computed tomography (CT)-guided biopsy is well established. There is also limited data comparing US- and CT-guided biopsy. We aimed to clarify the efficacy and safety of US-guided biopsy for thoracic lesions adjacent to the chest wall. METHODS: We retrospectively enrolled consecutive patients who underwent US- or CT-guided percutaneous biopsies for thoracic lesions adjacent to the chest wall between April 2012 and December 2017. Clinical characteristics, lesion size, lesion-pleura contact arc length (LPCAL), diagnostic rate, and complications were compared between the 2 groups. RESULTS: This study enrolled 61 US-guided and 70 CT-guided biopsies. No significant difference was found in age or sex. The lesion size and LPCAL in the US-guided group were significantly larger than those in the CT-guided group (P<0.0001). The diagnostic rate was marginally higher in the US-guided group (93.4%) than in the CT-guided group (84.3%) (P=0.101). When the median cut-off of the LPCAL was defined as 40 mm in all cases, the diagnostic rate for lesion size >40 mm was significantly higher in the US-guided group than in the CT-guided group (P=0.009). Complication rates were significantly lower in the US-guided group (3.3%) than in the CT-guided group (24.3%) (P<0.001). CONCLUSIONS: US-guided percutaneous needle biopsy for thoracic lesions adjacent to the chest wall is a feasible technique compared with CT-guided biopsy because of its higher diagnostic rate with a longer LPCAL and reduced complications.

Dose Escalation Study of Concurrent Chemoradiotherapy With the Use of Involved-field Conformal Radiotherapy and Accelerated Hyperfractionation in Combination With Cisplatin and Vinorelbine Chemotherapy for Stage III Non-small Cell Lung Cancer: The Final Report.

OBJECTIVES: A phase I study to determine a recommended dose of thoracic radiotherapy using accelerated hyperfractionation for unresectable non-small cell lung cancer was conducted. MATERIALS AND METHODS: We used chemotherapy of a cisplatin doublet and 2 dose levels of radiation with accelerated hyperfractionation. The radiation dose levels were: a total dose of 60 Gy in 40 fractions at level 1, and 66 Gy in 44 fractions at level 2. Eligible patients with unresectable stage III non-small cell lung cancer received cisplatin and vinorelbine. Radiation therapy started on day 2 of chemotherapy and was delivered twice daily for 5 days a week. RESULTS: Total 12 patients were enrolled, with 6 patients each at dose levels 1 and 2. Dose-limiting toxicity was noted in 2 patients at level 1; one patient had grade 3 febrile neutropenia and the other patient had grade 3 esophagitis. No dose-limiting toxicity was noted in the 6 patients at level 2. Grade 3 to 4 leukopenia, neutropenia, and anemia were noted in 11 (92%), 9 (75%), and 8 (67%) of the total 12 patients, respectively. Grade 3 anorexia and infection were noted in 2 patients (17%) at each level. Grade 3 nausea, fatigue, esophagitis, and febrile neutropenia were noted in 1 patient (8%) at each level. The response rate in the total 12 patients was 83.3%. The median progression-free survival time and the median overall survival time were 10.7 and 24.2 months, respectively. CONCLUSIONS: Sixty-six gray in 44 fractions is the recommended dose for the following phase II study.

PIK3CA mutation as a distinctive genetic feature of non-small cell lung cancer with chronic obstructive pulmonary disease: A comprehensive mutational analysis from a multi-institutional cohort.

OBJECTIVES: Non-small cell lung cancer (NSCLC) and chronic obstructive pulmonary disease (COPD) have been proposed to have a mutual developmental mechanism, but their association has not been fully understood. We aimed to examine the association of the mutational landscape of NSCLC with co-morbid COPD. MATERIALS AND METHODS: A total of 197 surgical specimens of early stage NSCLC were retrospectively collected from two independent sources, namely, the Japan Molecular Epidemiology for Lung Cancer Study and the Osaka City University Hospital cohort from 2010 to 2013. COPD and its severity were defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines and grading system. For molecular profiling of NSCLC patients with COPD, the extracted DNAs were deep-sequenced using next generation sequence technologies for somatic mutations in a maximum 72 cancer-associated genes. Logistic regression analysis was performed to evaluate the impact of COPD on the somatic mutations. RESULTS: The COPD group (n=77), including 56 GOLD 1 and 21 GOLD 2 or 3 patients, had 58 squamous cell lung carcinoma (SCC) cases and 19 adenocarcinoma cases. The non-COPD group (n=120) had 53 SCC cases, 64 adenocarcinoma cases, and three cases with other histology. The frequency of PIK3CA mutation was significantly higher in the COPD group than in the non-COPD group (10.4% vs. 1.7%, p=0.015). Meanwhile, NFE2L2 mutation was observed only in SCC cases, with no difference in the frequency between the two groups (17.2% vs. 17.0%). In the multivariate logistic regression model with consideration for COPD status, age, smoking dose, pathological stage, and histology, significantly more PIK3CA mutation was observed in the presence of COPD (odds ratio=5.31, 95% CI: 1.03-27.29, p=0.046). CONCLUSIONS: PIK3CA mutation is a distinctive genetic feature of NSCLC with COPD, regardless of age, smoking dose, pathological stage, and histology.