En Bloc Resection of a Primary Tumor and Lymph Nodes in Non-Small-Cell Lung Cancer.

PURPOSE: We established a novel surgical procedure for resectable non-small-cell lung cancer (NSCLC), which involves resection of the affected lobe and regional lymph nodes without separation, namely en bloc surgery. We introduced the technical details and early and late outcomes by comparing them with those of conventional surgery. METHODS: We retrospectively analyzed patients who underwent lobectomy with hilar and mediastinal lymph node dissection for stages I-III NSCLC. A propensity score-matched analysis was performed based on demographic variables. RESULTS: Propensity score-matching yielded 317 pairs. En bloc surgery was not associated with a longer operation time, a higher amount of intraoperative bleeding, or a higher frequency of postoperative complications. The number of resected lymph nodes (P = 0.277) and frequency of N upstaging (P = 0.587) did not differ between the groups. However, en bloc surgery was associated with higher overall survival in comparison to conventional surgery (P = 0.012). According to a stratification analysis, the survival advantage of en bloc surgery over conventional surgery was remarkable in pathological N-positive disease (P = 0.005), whereas it disappeared in pathological N-negative disease (P = 0.147). CONCLUSION: En bloc surgery is feasible and can be performed in patients with possible N-positive NSCLC.

Adjuvant Chemotherapy in Addition to Neoadjuvant Chemotherapy for Locally Advanced Non-small Cell Lung Cancer.

BACKGROUND/AIM: The prognostic impact of adjuvant cytotoxic chemotherapy for patients with resectable locally advanced non-small cell lung cancer (NSCLC) who underwent surgery after neoadjuvant chemotherapy remains unclear. PATIENTS AND METHODS: A retrospective chart review was performed to identify patients who underwent surgery following neoadjuvant therapy for clinical T3N0 or N1-N2 resectable NSCLC between 2011 and 2016 at our hospital. Survival outcomes were analyzed with the Kaplan-Meier method and a Cox proportional hazard model. RESULTS: Thirty-eight patients were identified. The median recurrence-free survival (RFS) was 50.6 months and overall survival (OS) was 75.2 months. Patients who had undergone adjuvant chemotherapy were not associated with a favorable RFS (hazard ratio=1.01, p=0.98) or OS (hazard ratio=0.72, p=0.55), as compared with those who had not. However, subgroup analysis revealed that hazard ratio based on RFS and OS varied greatly between subgroups, suggesting that selected patients might benefit from adjuvant therapy, while others might be harmed by it. For example, in surgical-pathological stage III disease, adjuvant therapy showed a favorable RFS (HR=0.22, 95%CI=0.02-2.57, p=0.23) and OS (HR=0.36, 95%CI=0.03-4.01, p=0.40). Conversely, in surgical-pathological stage 0-II disease, adjuvant therapy showed an unfavorable RFS (HR=1.40, 95%CI=0.49-3.96, p=0.53) and OS (HR=0.95, 95%CI=0.29-3.12, p=0.93). CONCLUSION: Regardless of the negative findings in our overall patient cohort, our results may be beneficial in identifying patients who may likely benefit from adjuvant therapy. This contribution could assist the planning of large-scale prospective studies.

Prognostic Outcome of Pulmonary Resection for Pulmonary Metastases from Gastric Cancer.

PURPOSE: Regardless of the devastating outcomes of pulmonary resection for metastases from gastric cancer, a handful of patients survive long after pulmonary metastasectomy. This study aimed to identify a good candidate for pulmonary resection for metastases from gastric cancer. METHODS: Between 2005 and 2023, 564 patients underwent pulmonary metastasectomy in our department, of which 12 patients underwent pulmonary resection for metastases from gastric cancer. Variables evaluated were the number and size of metastatic lesions, surgical procedure, disease-free interval (DFI), and the serum carcinoembryonic antigen at pulmonary metastasectomy. RESULTS: The DFI following gastrectomy ≤12.5 months group had a significantly worse overall survival (OS) than the other group (p = 0.005). A comparison between DFI following gastrectomy ≤12.5 months group and DFI following gastrectomy >12.5 months group showed a significant difference in serum carcinoembryonic antigen (CEA) value at pulmonary metastasectomy (p = 0.048). The serum CEA value at pulmonary metastasectomy >5.8 ng/ml group had a significantly worse OS than the other group (p = 0.001). CONCLUSION: Pulmonary metastasectomy can be indicated in some patients with metastasis from gastric cancer who have longer DFI from gastrectomy and lower serum CEA at pulmonary metastasectomy.

Prediction of Pleural Lavage Cytology According to Thin-Section Computed Tomography in Non-Small-Cell Lung Cancer.

BACKGROUND: Although the positive rate of preresection pleural lavage cytology (PLC) is low, it is an important indicator of poor prognosis for non-small-cell lung cancer patients with frequent pleural dissemination (PD) recurrence. Thin-section computed tomography (TSCT) can reveal relationships between a primary tumor and the pleura at 1 to 2 mm intervals, and this is associated with visceral pleural invasion (VPI). However, its association with PLC remains unclear. Therefore, we aimed to improve PLC efficiency and predict PD recurrence by understanding the relationship between PLC and preoperative TSCT findings. PATIENTS AND METHODS: Between January 2014 and December 2018, we reviewed 978 patients with non-small-cell lung cancer who underwent PLC tests during complete resection surgery. Preoperative TSCT findings were evaluated, and factors with the highest specificity (proportion of patients with radiologically to pathologically diagnosed positive PLC) were investigated. We also evaluated their relationships with VPI and PD recurrence. RESULTS: PLC positive was identified in 55 (5.6%) of the 978 patients. The two TSCT findings predicting PLC results, "the absence of pleural findings," ie, tumor not attached to pleura or without pleural tag, and "consolidation-to-tumor ratio ≤0.5", had a specificity of 100% (95% confidence interval: 90.4%-100%); additionally, all cases with these findings were VPI negative and had no PD recurrence. And 24% of the cohort had either of these findings. CONCLUSION: The absence of pleural findings and/or consolidation-to-tumor ratio ≤0.5 of primary tumor on preoperative TSCT can predict PLC negativity with very high probability; therefore, PLC can be omitted for such patients.

Prognostic significance of preoperative to postoperative serum carcinoembryonic antigen ratio after lobectomy for lung adenocarcinoma.

INTRODUCTION: Lung adenocarcinoma with a preoperatively elevated serum carcinoembryonic antigen (CEA) value has a relatively poor postoperative prognosis. Although surgical resection generally results in a reduction in the CEA value, the significance of the change in the CEA value on the prognostic outcome remains unclear. METHODS: Our study included 133 patients who underwent lobectomy with curative intent for lung adenocarcinoma representing a preoperative CEA value > 5.0. Statistical analysis was performed using a receiver operating characteristic analysis and a stepwise Cox proportional hazards analysis. RESULTS: Both the postoperative CEA value and postoperative-to-preoperative CEA ratio (CEA ratio) significantly affected the survival. Although the CEA ratio was not predictive of the survival in patients with postoperative CEA ≤ 6.2 ng/ml (n = 105), it was predictive in the remaining patients with postoperative CEA > 6.2 ng/ml (n = 28). Patients with postoperative CEA > 6.2 ng/ml and a CEA ratio ≥ 0.39 (n = 7) showed the worst survival outcome. According to the multivariate analysis, the CEA ratio and postoperative nodal status were significant predictors of the survival in overall patients. CONCLUSION: The CEA ratio may be a useful prognostic marker in patients who undergo lobectomy for lung adenocarcinoma and show postoperative CEA > 6.2 ng/ml. A high CEA ratio may indicate the presence of a subclinical residual tumor, which may lead to the development of subsequent recurrence.

A case of attempted transbronchial spigot insertion for fistulous pyothorax in the residual pleural airspace after pleurectomy/decortication for malignant pleural mesothelioma.

Pleurectomy/decortication for malignant pleural mesothelioma is a relatively recent surgical approach for which there is a dearth of information on complications, especially in the late postoperative period. A 70-year-old man was diagnosed with right epithelioid malignant pleural mesothelioma and underwent pleurectomy/decortication. Computed tomography at 6 months after surgery revealed nodules on the surface of the right lung. These nodules gradually increased in size and were diagnosed as recurrent disease. Immunotherapy was started, but treatment was discontinued a few days after the first course due to pneumonitis. Subsequent oral prednisolone therapy for about 2 months ameliorated pneumonitis, but fistulous pyothorax developed. During attempted transbronchial occlusion of the responsible bronchus, some spigots penetrated the empyema cavity. Open window thoracotomy was performed on the following day. This case suggests that if there is no change in diameter between the proximal and distal parts of the responsible bronchus, transbronchial occlusion should not be chosen.

Long term outcomes beyond 5 years after pulmonary resection for non-small-cell lung cancer.

OBJECTIVES: We investigated the incidence of late recurrence beyond 5 years after pulmonary resection and aimed to identify candidates for long-term surveillance. METHODS: We retrospectively reviewed the medical records of 978 non-small-cell lung cancer patients who underwent pulmonary resection between 2002 and 2015 and survived without recurrence for 5 years. Clinicopathological factors associated with recurrence-free survival beyond 5 years after surgery were investigated using univariate and multivariate analyses. The development of late metachronous malignancies was also investigated. RESULTS: The median follow-up period from 5 years post-surgery was 27 months in the whole cohort. Late recurrence occurred in 37 (3.8%) patients. Late metachronous malignancies were diagnosed in 116 patients (11.9%), including 57 (5.8%) with lung cancer. One-, three-, and five-year recurrence-free survival rates beyond 5 years after surgery were 97.6%, 94.7%, and 94.7%, respectively. The recurrence-free survival of patients with pN1-2 was significantly poorer than that of patients with pN0 disease. Multivariate analysis revealed that adenocarcinoma and pN1-2 status were significantly associated with poor recurrence-free survival beyond 5 years post-surgery (P = 0.009 and 0.007, respectively). CONCLUSIONS: Non-adenocarcinoma histology and pN0 status were significant favorable factors for recurrence-free survival beyond 5 years post-surgery. The efficacies of long-term surveillance for the detection of late recurrence were considered limited for these populations. Twelve percent of the patients experienced late metachronous malignancies after pulmonary resection.

Successful Treatment with Osimertinib Based on Therapeutic Drug Monitoring in a Hemodialysis Patient with Non-Small Cell Lung Cancer: A Case Report.

Although osimertinib is a key drug in the treatment of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation, the safety in hemodialysis patients has not been established. A 76-year-old man was diagnosed with NSCLC with EGFR deletion mutation in exon 19. After treatment failure with first- and second-generation EGFR tyrosine kinase inhibitors, a T790M mutation was revealed by liquid biopsy. Hemodialysis was started three times a week because chronic renal failure worsened during treatment. Although the subsequent administration of osimertinib (80 mg daily) resulted in a tumor shrinkage and a gradual increase in the plasma concentration of osimertinib, which resulted in grade 3 general fatigue, reducing the dosage of osimertinib decreased its plasma concentration, leading to an improvement in his adverse event. Subsequently, with by adjusting the dosage while periodically measuring the plasma concentration of osimertinib, a stable therapeutic effect was sustained over the long term with no symptoms. Periodic plasma concentration measurements may be indispensable for successful treatment with osimertinib in hemodialysis patients.

Hidden history of the tobacco BY-2 cell line.

For almost 50 years, tobacco (Nicotiana tabacum) BY-2 cells have been widely recognized as an important cell line for plant biology. The cell line grows rapidly, can be synchronized to a high degree, and is excellent for imaging; over the years, these features have led to many high-impact discoveries. However, certain other uses of this cell line are virtually unknown. In the early days, I was involved in distributing the cells to laboratories around the world. Many of these scientists wanted to study the cell cycle; however, I also distributed the cells to scientists who were elucidating the mechanism of plant transformation by Agrobacterium tumefaciens. In fact, BY-2 cells played an essential role in the identification and analysis of Vir genes on the Ti plasmid; likewise, the cells were important for discovering the factor that induces the expression of Vir genes. Thus, BY-2 cells were crucial for the development of modern plant biotechnology. Here, I recount the story of how this came to pass and explain why the use of BY-2 cells in this work was never recognized.

Approach to Functions of BHLHE41/DEC2 in Non-Small Lung Cancer Development.

The circadian rhythm-related genes BHLHE40/DEC1 and BHLHE41/DEC2 have various functions under different cell and tissue conditions. BHLHE41/DEC2 has been reported to be both a cancer-suppressive and an oncogenic gene during cancer development. The effects of BHLHE41/DEC2 on differentiation have been examined using Bhlhe41/Dec2 knockout mice and/or in vitro differentiation models, and research has been conducted using genetic analysis of tumor cells, in vitro analysis of cancer cell lines, and immunohistochemical studies of the clinical samples. We summarize some of these studies, detail several problems, and consider possible reasons for contradictory results and the needs for further research.

Diagnostic sensitivity of solid volume measurement for pathological invasion in non-solid lung adenocarcinoma.

Background: In the current tumor-node-metastasis (TNM) classification, the clinical T descriptor is defined by solid size (SS) on a computed tomography (CT) slice and the pathological one is done by invasive size (IS) in microscopic evaluations. We sometimes experience discrepancies in diagnosis of both descriptors. A volume analyzing application enables semi-automatic measurement of three-dimensional (3D) parameters in cases where there are discrepancies in diagnosing tumors' solid size and IS. In this study, we aimed to evaluate the association between 3D parameters and pathological invasion in non-solid small-sized lung adenocarcinomas. Methods: We enrolled 246 consecutive patients who underwent pulmonary resection at Shizuoka Cancer Center. Patients with lung adenocarcinomas that were radiologically non-solid, node-negative and sized ≤3 cm were eligible. We used a volume analyzing application to retrospectively measure 3D parameters of max and mean Hounsfield units (HUs) and solid volume (SV). The cut-off value of these parameters for diagnosing invasive adenocarcinoma (IAD) was set by describing receiver operating characteristic (ROC) curves. The correlation of IAD with these parameters was compared to its correlation with the SS. This study was not registered. Results: Of 246 patients with adenocarcinoma, 183 (74.4%) had IADs. In multivariate analyses, the total size (TS) and SS were significantly associated with IAD (P=0.006, 0.001, respectively), whereas 3D parameters including SV were not (P=0.80). In radiological adenocarcinoma (2.1-3.0 cm), SV >300 mm3 diagnosed IAD with a higher sensitivity than that of the SS (0.93 and 0.83, respectively). Conclusions: TS >20 mm and SS >5 mm were well-correlated with IAD. SV measurement may complement the current computed tomographic diagnosis of IAD based on the SS (2.1-3.0 cm).

Clinical Significance of Nodal DCsign Expression in Non-small-cell Lung Cancer Patients.

BACKGROUND/AIM: Dendritic cells (DCs) are difficult to evaluate in lung regional lymph nodes because of region-specific structures, such as abundant trabeculae connecting the medullary and subcapsular sinuses, the latter of which contains few anthracotic macrophages. Therefore, DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DCsign)-positive DCs and CD68-positive macrophages are unlikely to show a typical distribution. The present study therefore explored quantitative factors connecting the nodal DC morphology to the patient outcome. MATERIALS AND METHODS: Lymph nodes from 34 non-small-cell lung cancer patients who underwent complete resection were used for immunohistochemical assessments of DCsign and CD68 and terminal deoxynucleotidyl transferase dUTP nick-end labeling. Preoperative patient blood samples were used for the quantitative evaluation of monocytes. RESULTS: The nodal DCs showed a complementary distribution with macrophages, thus few DCs were seen in clusters of macrophages. DCs often presented as a mesh-like rosette that was solitary or connected to a DC cluster. DCs disappeared, and some macrophages were apoptotic when surrounded by cancer cells that have metastasized to lymph nodes. The proportional area of a DC cluster was significantly associated with the histological differentiation of cancer (p=0.013), with a higher ratio tending to lead to a better overall survival (p=0.059), and significantly so in adenocarcinoma (p=0.007). The rosette number was significantly correlated with the smoking index and blood monocyte number (p=0.013 and p=0.005, respectively). CONCLUSION: The nodal DC morphology appears useful as a prognostic factor and may lead to a new phase of clinicopathological studies of solid cancers.

The efficacy of a machine learning algorithm for assessing tumour components as a prognostic marker of surgically resected stage IA lung adenocarcinoma.

BACKGROUND: The importance of the stromal components in tumour progression has been discussed widely, but their prognostic role in small size tumours with lepidic components is not fully understood. Applying digital tissue image analysis to whole-slide imaging may enhance the accuracy and reproducibility of pathological assessment. This study aimed to evaluate the prognostic value of tumour components of lung adenocarcinoma by measuring the dimensions of the tumour consisting elements separately, using a machine learning algorithm. METHODS: Between September 2002 and December 2016, 317 patients with surgically resected, pathological stage IA adenocarcinoma with lepidic components were analysed. We assessed the whole tumour area, including the lepidic components, and measured the epithelium, collagen, elastin areas and alveolar air space. We analysed the prognostic impact of each tumour component. RESULTS: The dimensions of the epithelium and collagen areas were independent significant risk factors for recurrence-free survival (hazard ratio, 8.38; 95% confidence interval, 1.14-61.88; P = 0.037, and hazard ratio, 2.58; 95% confidence interval, 1.14-5.83; P = 0.022, respectively). According to the subgroup analysis when combining the epithelium and collagen areas as risk factors, patients with tumours consisting of both large epithelium and collagen areas showed significantly poor prognoses (P = 0.002). CONCLUSIONS: We assessed tumour components using a machine learning algorithm to stratify the post-operative prognosis of surgically resected stage IA adenocarcinomas. This method might guide the selection of patients with a high risk of recurrence.

A case of ectopic cervical thymoma with myasthenia gravis mimicking a parathyroid tumour.

Reports of cervical thymoma with myasthenia gravis are rare. In addition, 99mTc-MIBI (methoxyisobutylisonitrile:sestamibi) scintigraphy is a useful diagnostic examination for enlarged parathyroid tumours; however, there are a few reports of its accumulation in thymoma. Among them, there are no reports of cervical thymomas with 99mTc-MIBI accumulation complicated by myasthenia gravis. In this study, we performed surgery on a patient with preoperative myasthenic crisis accompanied by a cervical thymoma and a parathyroid tumour. Preoperatively, the cervical mass was determined to be a parathyroid tumour and was complicated by myasthenia gravis without thymic tumour. However, a pathological examination revealed that the cervical tumour with 99mTc-MIBI accumulation was a Type B2 thymoma, and a parathyroid tumour was identified in the vicinity. We report a very rare case in which symptoms improved with surgery.

Clinical significance of ALKBH4 expression in non-small cell lung cancer.

Background: Gene methylation is deeply involved in epigenetics and affects both the development and maintenance of homeostasis and carcinogenesis. ALKBH4 is a member of the AlkB homolog (ALKBH) family that controls demethylation of DNA and RNA. Methods: This study enrolled 160 patients with non-small cell lung cancer (NSCLC) who underwent complete resection. The expression of ALKBH4 in cancer tissue was evaluated by immunohistochemistry. The correlation among the expression of ALKBH4, clinicopathological factors, and prognostic outcome was evaluated. Results: In the NSCLC clinical samples, the expression of ALKBH4 was identified not only in cell membranes but also in the cytoplasm of cancer cells. In 140 of 160 cases, ALKBH4 was more highly expressed in the cancerous tissue than in the surrounding normal tissue. The proportion of cancer cells expressing ALKBH4 was higher in adenocarcinoma than in other histological types. In addition, the expression intensity of ALKBH4 in each cancer cell was also stronger in adenocarcinoma than in squamous cell carcinoma. The expression of ALKBH4 was not associated with clinicopathological factors, except for histological type. In adenocarcinoma, the recurrence-free survival (RFS) and overall survival (OS) rates were significantly lower in the ALKBH4-positive group than in the ALKBH4-negative group (P=0.008, 0.031, respectively). A multivariate logistic regression analysis indicated that the ALKBH4 expression was an independent prognostic factor for RFS (P=0.003) and OS (P=0.013). The expression of ALKBH4 was observed in all four patients with adenocarcinoma in situ. Conclusions: The ALKBH4 expression may be a useful predictor of the postoperative outcomes of lung adenocarcinoma (LUAD) patients.

Lobe-specific nodal dissection with intraoperative frozen section analysis for clinical stage-I non-small cell lung cancer: a validation study by propensity score matching.

OBJECTIVE: Lobe-specific nodal dissection (LND) is increasingly used for non-small cell lung cancer (NSCLC) in Japan; however, its treatment validity remains unclarified. Since 2013, LND has been used as a standard procedure for clinical stage-I (c-stage-I) NSCLC at our institution. We aimed to evaluate its validity using intraoperative frozen section analysis (FSA) for c-stage-I NSCLC. METHODS: The participants comprised patients with NSCLC who underwent LND between 2013 and 2016 (n = 307) or systematic nodal dissection (SND) between 2002 and 2013 (n = 367) for c-stage-I disease. FSA was routinely performed in LND to examine at least three stations. Outcomes were compared between the LND and SND groups. Patients in whom LND was converted to SND due to metastasis on FSA of the sampled lymph node were still categorized into the LND group, i.e., intention-to-treat analysis. The prognostic impact was compared using propensity score matching. RESULTS: The rate of conversion from LND to SND was 10.4%. Of the patients converted to SND, 12.5% had metastases outside the LND area. False-negative N2 results were detected in only 0.7% of the LND group patients after FSA. After matching, each group had 220 patients. There were no significant between-group differences in the lymph-node recurrence rate (7% vs. 6%), 5-year recurrence-free survival (80.1% vs. 79.0%), and overall survival (90.4% vs. 90.3%). CONCLUSIONS: LND with intraoperative FSA is a valid modality that could serve as a standard surgical procedure for c-stage-I NSCLC. Intraoperative FSA may lower the residual lymph-node metastasis risk in LND.

Altered lymphatic structure and function in pleural anthracosis: negative role in skip N2 metastasis.

OBJECTIVES: The present study investigated whether or not pleural anthracosis is associated with changes in the pleural lymphatic structures or function, which would interfere with nodal skip metastasis. METHODS: This study comprised 2 different case series. In the first series, we observed pleural lymphatic drainage using near-infrared fluorescent endoscopy by the subpleural injection of indocyanine green immediately after thoracotomy for lung cancer. We also performed a histological assessment of the pleura. In the second series, we reviewed the nodal metastatic pattern (skip or non-skip metastasis) in pathological N2 lung cancer involving the pleura. These findings were compared with the severity of pleural anthracosis, which was quantified by thoracoscopic vision and a software-based imaging analysis. RESULTS: In the first series (n = 42), pleural lymphatic drainage was not visualized in 19 (45%) patients who had relatively severe anthracosis, while it was visualized in the remaining 23 (55%) patients who had relatively minimal anthracosis. Histologically, severe anthracosis was associated with pleural thickening accompanied by a decreased incidence of straight-running lymphatic vessels and, in turn, an increased incidence of short lymphatic vessels, which was suggested to be the result of pleural remodelling. In the second series (n = 53), a skip metastatic pattern was found in 24 (45%) patients who predominantly had less-severe anthracosis, while a non-skip metastatic pattern was found in 29 (55%) patients who predominantly had severe anthracosis. CONCLUSIONS: Pleural anthracosis was associated with pathological changes in the pleural lymphatics and decreased pleural lymphatic drainage, thereby interfering with nodal skip metastasis.

Validity of surgical decision based on intraoperative frozen section diagnosis for unconfirmed pulmonary nodules with previous malignancy.

OBJECTIVES: The lung is a major target organ of metastasis in several cancers. To distinguish primary lung cancer from pulmonary metastases is a clinical challenge. Small pulmonary nodules (PNs) are frequently diagnosed by frozen section diagnosis (FSD) intraoperatively after resection. Intraoperative FSD is very important to determine the extent of subsequent surgical procedures. This study aimed to know the validity of surgical decision based on FSD for preoperatively unconfirmed PN with previous malignancy. METHODS: We retrospectively evaluated 96 patients with suspected malignant PN who underwent intraoperative FSD between 2018 and 2020. Intraoperative FSD, final diagnosis, and surgical procedure data were examined. RESULTS: Surgical procedure adequacy, based on FSD for preoperatively unconfirmed PN with previous malignancy, was 91% (88/96). The overall diagnostic accuracy of FSD was 83.3% (80/96). Discrepancy was noted in two cases (2.1%), and conclusive diagnosis could not be reached intraoperatively in 14 cases (14.6%). A second surgery was required in three patients and no additional excision for primary lung cancer was performed in three patients. Conversely, there were three cases of over-surgery, namely, lobectomy for pulmonary metastasis. CONCLUSIONS: Surgical decision-making based on FSD for preoperatively unconfirmed PN in patients with previous malignancy was generally adequate. However, there were inadequate or excessive surgical procedures due to limitations in the accuracy of intraoperative FSD. Improving the accuracy of intraoperative FSD is a necessary step for obtaining adequate surgical decision-making and precision medicine.

BHLHE41/DEC2 Expression Induces Autophagic Cell Death in Lung Cancer Cells and Is Associated with Favorable Prognosis for Patients with Lung Adenocarcinoma.

Lung cancer constitutes a threat to human health. BHLHE41 plays important roles in circadian rhythm and cell differentiation as a negative regulatory transcription factor. This study investigates the role of BHLHE41 in lung cancer progression. We analyzed BHLHE41 function via in silico and immunohistochemical studies of 177 surgically resected non-small cell lung cancer (NSCLC) samples and 18 early lung squamous cell carcinoma (LUSC) cases. We also examined doxycycline (DOX)-inducible BHLHE41-expressing A549 and H2030 adenocarcinoma cells. BHLHE41 expression was higher in normal lung than in lung adenocarcinoma (LUAD) tissues and was associated with better prognosis for the overall survival (OS) of patients. In total, 15 of 132 LUAD tissues expressed BHLHE41 in normal lung epithelial cells. Staining was mainly observed in adenocarcinoma in situ and the lepidic growth part of invasive cancer tissue. BHLHE41 expression constituted a favorable prognostic factor for OS (p = 0.049) and cause-specific survival (p = 0.042) in patients with LUAD. During early LUSC, 7 of 18 cases expressed BHLHE41, and this expression was inversely correlated with the depth of invasion. DOX suppressed cell proliferation and increased the autophagy protein LC3, while chloroquine enhanced LC3 accumulation and suppressed cell death. In a xenograft model, DOX suppressed tumor growth. Our results indicate that BHLHE41 expression prevents early lung tumor malignant progression by inducing autophagic cell death in NSCLC.