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Lazertinib, a novel third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), demonstrates marked efficacy in EGFR-mutant lung cancer. However, resistance commonly develops, prompting consideration of therapeutic strategies to overcome initial drug resistance mechanisms. This study aimed to elucidate the adaptive resistance to lazertinib and advocate novel combination treatments that demonstrate efficacy in preventing resistance as a first-line treatment for EGFR mutation-positive NSCLC. We found that AXL knockdown significantly inhibited lung cancer cell viability in the presence of lazertinib, indicating that AXL activation contributes to lazertinib resistance. However, long-term culture with a combination of lazertinib and AXL inhibitors led to residual cell proliferation and increased the MCL-1 expression level, which was mediated by the nuclear translocation of the transcription factor YAP. Triple therapy with an MCL-1 or YAP inhibitor in combination with lazertinib and an AXL inhibitor significantly reduced cell viability and increased the apoptosis rate. These results demonstrate that AXL and YAP/MCL-1 signals contribute to adaptive lazertinib resistance in EGFR-mutant lung cancer cells, suggesting that the initial dual inhibition of AXL and YAP/MCL-1 might be a highly effective strategy in eliminating lazertinib-resistant cells., (© 2024 The Author(s). Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

We previously reported that combined therapy with epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) osimertinib and AXL inhibitor ONO-7475 is effective in preventing the survival of drug-tolerant cells in high-AXL-expressing EGFR-mutated non-small cell lung cancer (NSCLC) cells. Nevertheless, certain residual cells are anticipated to eventually develop acquired resistance to this combination therapy. In this study, we attempted to establish a multidrug combination therapy from the first-line setting to overcome resistance to this combination therapy in high-AXL-expressing EGFR-mutated NSCLC. siRNA screening assay showed that fibroblast growth factor receptor 1 (FGFR1) knockdown induced pronounced inhibition of cell viability in the presence of the osimertinib-ONO-7475 combination, which activates FGFR1 by upregulating FGF2 via the c-Myc pathway. Cell-based assays showed that triple therapy with osimertinib, ONO-7475, and the FGFR inhibitor BGJ398 significantly increased apoptosis by increasing expression of proapoptotic factor Bim and reduced cell viability compared with that observed for the osimertinib-ONO-7475 therapy. Xenograft models showed that triple therapy considerably suppressed tumor regrowth. A novel therapeutic strategy of additional initial FGFR1 inhibition may be highly effective in suppressing the emergence of osimertinib- and ONO-7475-resistant cells., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: T. Yamada received commercial research grants from Ono Pharmaceutical, Janssen Pharmaceutical K.K., AstraZeneca, and Takeda Pharmaceutical Company Limited and speaking honoraria from Eli Lilly and Chugai-Roche. H. Kawachi received personal fees from Ono Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, AstraZeneca, Taiho Pharmaceutical, Eli Lilly Japan, and MSD outside the purview of the submitted work. A. Osoegawa received consultant honoraria from AstraZeneca and speaking honoraria from AstraZeneca, MSD Japan, Chugai Pharmaceutical, Bristol Myers Squibb, and Ono Pharmaceutical. T. Sakai received research grants from Otsuka Pharmaceutical, Taiho Pharmaceutical, and Oncolys BioPharma and a patent fee from JT Pharmaceutical. T. Yasuhiro and R. Kozaki are paid employees of Ono Pharmaceutical. S. Yano received research grants from Chugai-Roche and Boehringer-Ingelheim and speaking honoraria from Amgen, Chugai-Roche, Boehringer-Ingelheim, Novartis, and Pfizer. K. Takayama received research grants from Chugai-Roche and Ono Pharmaceutical and personal fees from AstraZeneca, Chugai-Roche, MSD-Merck, Eli Lilly, Boehringer-Ingelheim, and Daiichi-Sankyo. The other authors have no conflicts of interest to declare., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Recent therapeutic strategies for KRAS-mutated cancers that inhibit the MAPK pathway have attracted considerable attention. The RAF/MEK clamp avutometinib (VS-6766/CH5126766/RO5126766/CKI27) is promising for patients with KRAS-mutated cancers. Although avutometinib monotherapy has shown clinical activity in patients with KRAS-mutated cancers, effective combination strategies will be important to develop., Methods: Using a phosphorylation kinase array kit, we explored the feedback mechanism of avutometinib in KRAS-mutated NSCLC cells, and investigated the efficacy of combining avutometinib with inhibitors of the feedback signal using in vitro and in vivo experiments. Moreover, we searched for a biomarker for the efficacy of combination therapy through an in vitro study and analysis using the The Cancer Genome Atlas Programme dataset., Results: Focal adhesion kinase (FAK) phosphorylation/activation was increased after avutometinib treatment and synergy between avutometinib and FAK inhibitor, defactinib, was observed in KRAS-mutated NSCLC cells with an epithelial rather than mesenchymal phenotype. Combination therapy with avutometinib and defactinib induced apoptosis with upregulation of Bim in cancer cells with an epithelial phenotype in an in vitro and in vivo study., Conclusions: These results demonstrate that the epithelial-mesenchymal transition status may be a promising biomarker for the efficacy of combination therapy with avutometinib and defactinib in KRAS-mutated NSCLC., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Recently, novel Kirsten rat sarcoma viral oncogene homolog (KRAS) inhibitors have been clinically developed to treat KRAS G12C-mutated non-small cell lung cancer (NSCLC) patients. However, achieving complete tumor remission is challenging. Therefore, the optimal combined therapeutic intervention with KRAS G12C inhibitors has a potentially crucial role in the clinical outcomes of patients. We investigated the underlying molecular mechanisms of adaptive resistance to KRAS G12C inhibitors in KRAS G12C-mutated NSCLC cells to devise a strategy preventing drug-tolerant cell emergence. We demonstrate that AXL signaling led to the adaptive resistance to KRAS G12C inhibitors in KRAS G12C-mutated NSCLC, activation of which is induced by GAS6 production via YAP. AXL inhibition reduced the viability of AXL-overexpressing KRAS G12C-mutated lung cancer cells by enhancing KRAS G12C inhibition-induced apoptosis. In xenograft models of AXL-overexpressing KRAS G12C-mutated lung cancer treated with KRAS G12C inhibitors, initial combination therapy with AXL inhibitor markedly delayed tumor regrowth compared with KRAS G12C inhibitor alone or with the combination after acquired resistance to KRAS G12C inhibitor. These results indicated pivotal roles for the YAP-GAS6-AXL axis and its inhibition in the intrinsic resistance to KRAS G12C inhibitor., Competing Interests: Declaration of competing interest T. Yamada received commercial research grants from Pfizer, Ono Pharmaceutical, Janssen Pharmaceutical K.K., AstraZeneca, and Takeda Pharmaceutical Company Limited and has received speaking honoraria from Eli Lilly. H. Kawachi received personal fees from Ono Pharmaceutical Co. Ltd., Chugai Pharmaceutical Co. Ltd., AstraZeneca KK, Taiho Pharmaceutical Co. Ltd., Eli Lilly Japan KK, and MSD KK, outside the purview of the submitted work. N. Furuya received personal fees from AstraZeneca, Chugai, Boehringer Ingelheim, Bristol-Myers Squibb, Eli Lilly, MSD, Pfizer, Taiho, and Novartis. S. Watanabe received grants and personal fees from Boehringer Ingelheim and Nippon Kayaku. Personal fees from Lilly, Pfizer, Novartis Pharma, AstraZeneca, Chugai Pharma, Bristol-Myers, Ono Pharmaceutical, Daiichi Sankyo, and Taiho Pharmaceutical. S. Yano received research grants from Chugai Pharmaceutical and Boehringer-Ingelheim and has received speaking honoraria from Amgen, Chugai Pharmaceutical, Boehringer-Ingelheim, Novartis, and Pfizer. T. Sakai received research grants from Otsuka Pharmaceutical, Taiho Pharmaceutical and Oncolys BioPharma, and a patent fee from JT Pharmaceutical. K. Takayama reports receiving research grants from Chugai-Roche Co., and Ono Pharmaceutical Co., and personal fees from AstraZeneca Co., Chugai-Roche Co., MSD-Merck Co., Eli Lilly Co., Boehringer-Ingelheim Co., and Daiichi-Sankyo Co.No potential conflicts of interest were disclosed by the other authors., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Context.—: The accurate identification of different lung adenocarcinoma histologic subtypes is important for determining prognosis but can be challenging because of overlaps in the diagnostic features, leading to considerable interobserver variability., Objective.—: To provide an overview of the diagnostic agreement for lung adenocarcinoma subtypes among pathologists and to create a ground truth using the clustering approach for downstream computational applications., Design.—: Three sets of lung adenocarcinoma histologic images with different evaluation levels (small patches, areas with relatively uniform histology, and whole slide images) were reviewed by 17 international expert lung pathologists and 1 pathologist in training. Each image was classified into one or several lung adenocarcinoma subtypes., Results.—: Among the 4702 patches of the first set, 1742 (37%) had an overall consensus among all pathologists. The overall Fleiss κ score for the agreement of all subtypes was 0.58. Using cluster analysis, pathologists were hierarchically grouped into 2 clusters, with κ scores of 0.588 and 0.563 in clusters 1 and 2, respectively. Similar results were obtained for the second and third sets, with fair-to-moderate agreements. Patches from the first 2 sets that obtained the consensus of the 18 pathologists were retrieved to form consensus patches and were regarded as the ground truth of lung adenocarcinoma subtypes., Conclusions.—: Our observations highlight discrepancies among experts when assessing lung adenocarcinoma subtypes. However, a subsequent number of consensus patches could be retrieved from each cluster, which can be used as ground truth for the downstream computational pathology applications, with minimal influence from interobserver variability., Competing Interests: This paper is based on results obtained from a project, 19100971-0, commissioned by the New Energy and Industrial Technology Development Organization (NEDO)., (© 2023 College of American Pathologists.)

Cell-free DNA in human blood plasma (cfDNA) is now widely used and studied as a biomarker for several physiological and pathological situations. In addition to genetic and epigenetic alterations that provide information about the presence and the nature of non-constitutive DNA in the body, cfDNA concentration and size distribution may potentially be independent biomarkers suitable for monitoring at-risk patients and therapy efficacy. Here, we describe a simple, in-line, method, which measures cfDNA concentration and size distribution from only a few microliters of plasma without the need to extract and/or concentrate the DNA prior to the analysis. This method is based on a dual hydrodynamic and electrokinetic actuation, adapted for samples containing salts and proteins such as biological fluids. The method provides analytical performances equivalent to those obtained after purification and concentration of cfDNA, with a precision of ∼1% for size features and of 10-20% for the concentrations of the different size fractions. We show that concentration and size distribution of cfDNA analyzed from plasma can differentiate advanced lung cancer patients from healthy controls. This simple and cost-effective method should facilitate further investigations into the potential clinical usefulness of cfDNA size profiling.

EGFR-T790M mutation is a major mechanism underlying acquired resistance to first- and second-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs) in lung cancer with mutated EGFR. However, differences in the biological characteristics of T790M tumors based on treatment regimens with each generation of EGFR-TKI are not fully understood. We established cell lines with acquired resistance harboring EGFR-T790M mutation derived from xenograft tumors treated with each generation of EGFR-TKI and examined their biological characteristics with respect to third-generation EGFR-TKI osimertinib sensitivity. Second-generation EGFR-TKI dacomitinib-resistant cells with T790M-exhibited higher sensitivity to osimertinib than first-generation EGFR-TKI gefitinib-resistant cells with T790M via inhibition of AKT and ERK signaling and promotion of apoptosis. Furthermore, gefitinib-resistant cells showed enhanced intratumor heterogeneity accompanied by genomic instability and activation of alternative resistance mechanisms compared with dacomitinib-resistant cells; this suggests that the maintenance of EGFR dependency after acquiring resistance might depend on the type of EGFR-TKI. Our results demonstrate that the progression of tumor heterogeneity via both genetic and non-genetic mechanisms might affect osimertinib sensitivity in tumors with acquired resistance harboring EGFR-T790M mutation., (© 2022 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Introduction: The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the "neoplastic, benign neoplasm, and low-grade carcinoma" category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system., Methods: We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system., Results: The interobserver agreement was moderate in the JLCS-JSCC (k = 0.499) and PSC (k = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into "negative" or "atypical" by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as "suspicious" or "malignant" by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system., Conclusions: The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice., (© 2021 The Author(s). Published by S. Karger AG, Basel.)

Purpose: Currently, an optimal therapeutic strategy comprising molecularly targeted agents for treating EGFR -mutated non-small cell lung cancer (NSCLC) patients with acquired resistance to osimertinib is not available. Therefore, the initial therapeutic intervention is crucial for the prolonged survival of these patients. The activation of anexelekto (AXL) signaling is known to be associated with intrinsic and acquired resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs). In this study, we investigated the best therapeutic strategy to combat AXL-induced tolerance to EGFR-TKIs using the novel AXL inhibitor ONO-7475., Experimental Design: We examined the efficacy of ONO-7475 in combination with EGFR-TKIs in EGFR -mutated NSCLC cells using in vitro and in vivo experiments. We investigated the correlation between AXL expression in tumors and clinical outcomes with osimertinib for EGFR -mutated NSCLC patients with acquired resistance to initial EGFR-TKIs., Results: ONO-7475 sensitized AXL-overexpressing EGFR -mutant NSCLC cells to the EGFR-TKIs osimertinib and dacomitinib. In addition, ONO-7475 suppressed the emergence and maintenance of EGFR-TKI-tolerant cells. In the cell line-derived xenograft models of AXL-overexpressing EGFR -mutated lung cancer treated with osimertinib, initial combination therapy of ONO-7475 and osimertinib markedly regressed tumors and delayed tumor regrowth compared with osimertinib alone or the combination after acquired resistance to osimertinib. AXL expression in EGFR-TKI refractory tumors did not correlate with the sensitivity of osimertinib., Conclusions: These results demonstrate that ONO-7475 suppresses the emergence and maintenance of tolerant cells to the initial EGFR-TKIs, osimertinib or dacomitinib, in AXL-overexpressing EGFR -mutated NSCLC cells, suggesting that ONO-7475 and osimertinib is a highly potent combination for initial treatment., (©2020 American Association for Cancer Research.)

Squamous cell lung carcinoma (SQCLC) is an aggressive type of lung cancer. In contrast with the marked advances that have been achieved in the treatment of lung adenocarcinoma, there are currently no effective targeted therapies for SQCLC, for with cytotoxic drugs are still the main treatment strategy. Therefore, the present study aimed to develop novel combination therapies for SQCLC. The results demonstrated that a combined treatment with the potent histone deacetylase (HDAC) inhibitor OBP‑801 and the third‑generation anthracycline amrubicin synergistically inhibited the viability of SQCLC cell lines by inducing apoptosis signal‑regulating kinase 1 (ASK1)‑dependent, as well as JNK‑ and p38 mitogen‑activated protein kinase (MAPK)‑independent apoptosis. OBP‑801 treatment strongly induced the protein expression levels of thioredoxin‑interacting protein (TXNIP), and amrubicin treatment increased the levels of intracellular reactive oxygen species (ROS), which suggested that this combination oxidized and dissociated thioredoxin 2 (Trx2) from mitochondrial ASK1 and activated ASK1. Moreover, mouse xenograft experiments using human H520 SQCLC cells revealed that the co‑treatment potently suppressed tumor growth in vivo. These results suggested that a combined treatment with OBP‑801 and amrubicin may have potential as a therapeutic strategy for SQCLC.

Introduction: The classification of lung carcinoma is based on small biopsies and/or cytology in 80% of patients with non-small cell carcinoma. However, there is no widely accepted classification system for respiratory cytology. The Japan Lung Cancer Society (JLCS) and Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma with the following categories: (1) "negative for malignancy," (2) "atypical cells," (3) "suspicious for malignancy," and (4) "malignancy.", Objective: The aim of this work was to perform an interobserver reproducibility study to confirm the utility of the four-tiered reporting system on respiratory cytological samples., Methods: We analyzed 90 cytological samples obtained with bronchoscopy. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the three-, four-, and five-tiered reporting systems., Results: The interobserver agreement was fair in the three- (κ = 0.50), four- (κ = 0.45), and five-tiered (κ = 0.45) reporting systems. However, the four-tiered reporting system provided more precise information than the three-tiered reporting system in patient management. The risk of malignancy in the four-tiered reporting system was also stratified well: 19.3% for "negative for malignancy," 45.6% for "atypical cells," 74.7% for "suspicious for malignancy," and 88.1% for "malignancy.", Conclusions: The reporting system proposed by the JLCS and JSCC was designed to enhance the communication between clinicians and pathologists and among different institutions. It is simple and applicable to cytological diagnosis of any respiratory diseases. We propose establishing an international classification for respiratory cytology, harmonizing the reporting systems proposed by different countries., (© 2020 S. Karger AG, Basel.)

We present a 76-year-old man who underwent two lung resections for metastases originating from cancer of the Ampulla duodeni, 9 years-after pancreaticoduodenectomy with lymphadenectomy. Pancreaticoduodenectomy was performed in 2002; histological examination of the original tumor revealed a stage III tubular adenocarcinoma (pT3, N0, M0). Repetitive lung resection was performed in 2007 (left S8) and 2011 (right S1 and extirpation of a pericardial cyst). Although rarely performed, resection of bilateral pulmonary metastases from carcinoma of the papilla of Vater was done to improve the patient's chances for longterm survival.

In August 1997, a 68-year-old man presented with right pelvic pain. Pelvic computed tomography (CT) and bone scintigraphy showed a huge tumor of the right iliac bone. No other lesion was detected, in spite of a high serum carcinoembryonic antigen level (CEA, 963 ng/ml). In October 1997, the iliac bone tumor was widely resected, and thereafter was diagnosed to be a metastatic adenocarcinoma of unknown origin. After a resection, the serum CEA level dropped as low as 6.4 ng/ml, but gradually went up to 80 ng/ml in October 1999. Next, a lung tumor in the left upper lobe was detected by routine chest CT. In January 2000, a left upper lobectomy was performed, and based on not only the pathological findings but also on an immunohistochemical analysis for napsin A expression, the tumor was diagnosed to be lung adenocarcinoma. The histological and immunohistochemical findings in the previously resected bone lesion were completely compatible with those in the pulmonary tumor, which was finally regarded as M1 lung cancer. In October 2002, the patient was alive without any symptoms, although the serum CEA level was elevated again. We consider this case worthy of presentation because of its unique clinical course as well as the successful long-term survival after surgical treatment alone, for both the primary and metastatic lesions.

The drs gene was originally isolated from a rat primary embryo fibroblast cDNA library as a suppressor gene against v-src transformation. We have previously shown that expression of drs mRNA was markedly reduced in a variety of human cancer cell lines, including those of the colon, bladder, and ovary. Furthermore, introduction of drs cDNA by retrovirus vector into these cancer cell lines caused suppression of anchorage-independent growth without affecting cell proliferation. These findings suggest that down-regulation of drs mRNA is closely correlated with expression of malignant phenotypes in development of human cancers. To clarify the correlation between down-regulation of drs mRNA and malignant tumor formation in human tumor tissues, we examined the expression of drs mRNA in well-differentiated, moderately differentiated, and poorly differentiated lung adenocarcinoma tissues by in situ mRNA hybridization. The results clearly indicated that expression of drs mRNA was markedly reduced in 5 of 5 poorly differentiated lung adenocarcinomas examined but significantly expressed in normal lung tissues and 5 of 7 moderately-differentiated and 3 of 5 well-differentiated lung adenocarcinoma tissues. Neither gross deletion nor rearrangement of the drs genome was detected in these tissues. Down-regulation of drs mRNA was also observed in human lung adenocarcinoma cell lines derived from poorly differentiated adenocarcinomas. Our results suggest that down-regulation of drs mRNA is correlated with a poor degree of differentiation and progression of lung adenocarcinoma., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

Objective: This study was undertaken to investigate the value of the ground-glass opacity (GGO) area found on high-resolution computed tomography (HRCT) scanning as a preoperative prognostic indicator., Patients and Methods: We studied 104 patients with small-sized lung adenocarcinoma, 20 mm or less in diameter, between 1995 and 1999. Three independent radiologists semi-quantitatively scored the extent of GGO on HRCT as greater than or less than 50%. Three independent pathologists semi-quantitatively scored the extent of the bronchioloalveolar carcinoma (BAC) component of the tumor on histologic examination as greater than or less than 50%. As no relapse occurred in patients with GGO greater than 50%, multivariate analysis of this prognostic factor was not possible., Results: Fifty patients were scored as having both BAC and GGO greater than 50%, 36 as both BAC and GGO less than 50%, and 16 as BAC greater than 50% and GGO less than 50%. In only two patients (1.9%), BAC less than 50% was overestimated on HRCT as GGO greater than 50%. The sensitivity and specificity of GGO to BAC were 76 and 95%, respectively. The 3 year-relapse-free survival rates in each group of 52 patients with GGO greater than and less than 50% were 100 and 72%, respectively, after a median follow-up of 24 months. Univariate analysis indicated that both GGO and BAC areas were significantly correlated with cancer relapse (P=0.005 and P=0.002). The multivariate analysis revealed an independent prognostic influence of the BAC area on relapse-free survival (P=0.015, relative risk=0.07)., Conclusions: To date there has been no relapse among the 52 patients with GGO greater than 50%. This novel classification based on the semiquantitative analysis of GGO area on HRCT should become an useful independent preoperative indicator when deciding on operative procedure, and to predict the potential of relapse in patients with small adenocarcinoma arising from the peripheral lung.

Study Objectives: We performed a clinical trial of laser-induced fluorescence endoscopy (LIFE) for detection of precancerous lesions and cancer including carcinoma in situ (CIS), which are difficult to detect by white-light bronchoscopy., Design: Results with LIFE were compared with the criterion standard, white-light bronchoscopy. The evaluation of these endoscopic results spectrofluorometrically was examined, and pixels of LIFE images composed of digital signals for the intensities of red and green were analyzed., Setting: Tertiary-level hospital treating referrals and subjects with suspicious results in mass screening., Patients: We examined 65 subjects with suspected lung cancer by both methods, and performed biopsy on 216 lesions., Results: The accuracy of diagnosis by white-light bronchoscopy, with histopathologic results as the standard, was 48.6%. The accuracy by LIFE was 72.7%. The sensitivity of conventional bronchoscopy for detection of severe dysplasia (21 biopsy specimens) or cancer (28 biopsy specimens) was 61.2% and specificity was 85.0%. With results by LIFE added, these values were 89.8% and 78.4%, respectively. Of nine patients with CIS, only LIFE showed one lesion, and only LIFE showed the extent of seven of the lesions. The autofluorescence of eight lesions was measured spectrofluorometrically; normal bronchial tissue, severe dysplasia, and cancerous tissue had spectral differences. The red/green intensity of cancers on histograms of LIFE images generally was greater than the ratios for metaplasia or normal bronchial wall., Conclusions: Use of both methods should facilitate early detection. Evaluation by spectrofluorometry and analysis of digital signal intensity of results by LIFE make results more objective.

Recently, routine clinical use of CT scan has enabled the detection of many small pulmonary nodules. Concurrently, high-resolution CT(HRCT) has made great advances in the diagnosis of small peripheral lung cancer. In the tumor of adenocarcinoma, non-invasive bronchioloalveolar carcinoma(BAC) component having a replacement growth pattern of alveolar lining cells shows ground-glass opacity(GGO) on HRCT. On the basis of analysis of small peripheral adenocarcinoma (= < 2 cm), patients with tumors showing > = 50% GGO had no metastatic tendency. Therefore, simple wedge resection may be acceptable as a radical operation. On the other hand, since patients with tumors < 50% GGO had slight metastatic tendency depending upon the tumor size, segmentectomy with mediastinal lymph node sampling should be considered only for tumors = < 15 mm.

Two cases of primitive neuroectodermal tumor of the lung are reported. The first case is a 41-year-old man with a tumor in the left upper lung, and the second case is a 30-year-old woman with a tumor in the right lower lung. In both cases, the tumors originated in the lung but not in the chest wall. No distant metastasis was detected. In case 1, transcutaneous fine-needle biopsy (TCNB) revealed small round cell proliferation, although bronchoscopic examination showed no abnormal findings. Both the expression of Mic2 protein and t(11;22)(q24;q12) translocation were proved in the tumor cells. The tumor cells were positive for periodic acid-Schiff (PAS), neuron-specific enolase (NSE), and vimentin, but negative for Leu7, chromogranin A, and pro-gastrin-releasing peptide (ProGRP). In case 2, bronchoscopic examination showed only compressive change in right lower lobe bronchi. TCNB revealed small round tumor cells expressing Mic2 protein. The tumor cells were negative for leukocyte common antigen, S100 protein, pankeratin, chromogranin A, and desmin, but weakly positive for NSE and moderately positive for Ki-67 (MIB1). Both patients were successfully treated by the combination of surgical resection and chemotherapy, and are alive with no sign of recurrence for approximately 22 months in case 1 and 16 months in case 2.

Background: Bronchiolo-alveolar carcinoma (BAC) is often observed in lung adenocarcinoma, but its clinicopathological and prognostic significance, especially in small peripheral lung adenocarcinoma, remains undetermined., Methods: We assessed 206 consecutive cases of surgically resected small peripheral lung adenocarcinoma (less than 2 cm in diameter) recorded between 1973 and 1997. According to the component area of well differentiated BAC within maximally cut surface specimens of tumor tissue, we semiquantitatively classified the tumors into four types: those in which the BAC component comprised 0% (type I), 1% to 49% (type II), 50% to 99% (type III), and 100% (type IV) of the tumor tissue., Results: Forty tumors were classified as type I, 75 as type II, 74 as type III, and 17 as type IV. The tumors with less BAC, especially type I and II, showed a significantly more aggressive nodal involvement and tumor stage, and consequently a worse prognosis, while type IV tumors had no nodal involvement and the most favorable prognosis. The patients with type III showed clinicopathological characteristics somewhere between those of type II and type IV patients. Among stage I patients, however, those with type II had the worst prognosis, while those with type I showed as good a prognosis as the other two groups., Conclusions: This novel classification based on the degree of BAC involvement in small peripheral lung adenocarcinoma may reflect clinicopathological and prognostic characteristics. This classification may prove practical for planning therapeutic strategies, in particular surgical treatment.

Myoepithelial tumors occur mainly in the salivary glands, the sweat glands or the breast, but uncommonly in the lung. Herein, we describe two cases of myoepithelioma of the lung. Both patients were 58-year-old men, in whom the tumors were located in the right-upper bronchus and in the left-upper bronchus, respectively, with endobronchial growth pattern. Surgery was performed, but metastasis occurred into the forearm and hip muscles in the former case, and into the liver in the latter. Histologically, the tumor in the former was a spindle-plasmacytoid type, and that in the latter was a plasmacytoid type in part with squamous differentiation. Based on histochemical, immunohistochemical and ultrastructural analyses, both were compatible with myoepithelioma. The clinicopathological uniqueness of this neoplasm is discussed, together with a review of reports of this disease in the literature.