Nationwide prospective registry database of patients with newly diagnosed untreated pleural mesothelioma in Japan.

Due to the scarcity of large-sized prospective databases, the Japanese Joint Committee for Lung Cancer Registry conducted a nationwide prospective registry for newly diagnosed and untreated pleural mesothelioma. All new cases diagnosed pathologically as any subtype of pleural mesothelioma in Japan during the period between April 1, 2017, to March 31, 2019, were included before treatment. Data on survival were collected in April 2021. The eligible 346 patients (285 men [82.3%]; 61 women [17.7%]; median age, 71.0 years [range, 44-88]) were included for analysis. Among these patients, 138 (39.9%) underwent surgery, 164 (47.4%) underwent non-surgical therapy, and the remaining 44 (12.7%) underwent best supportive care. The median overall survival for all 346 patients was 19.0 months. Survival rates at 1, 2, and 3 years for all patients were, 62.8%, 42.3%, and 26.5%, respectively. Median overall survival was significantly different among patients undergoing surgery, non-surgical treatment, and best supportive care (32.2 months vs. 14.0 months vs. 3.8 months, p < 0.001). The median overall survival of patients undergoing pleurectomy/decortication and extrapleural pneumonectomy was 41.8 months and 25.0 months, respectively. Macroscopic complete resection resulted in longer overall survival than R2 resection and partial pleurectomy/exploratory thoracotomy (41.8 months vs. 32.2 months vs. 16.8 months, p < 0.001). Tumor shape, maximum tumor thickness, and sum of three level thickness were significant prognostic factors. The data in the prospective database would serve as a valuable reference for clinical practice and further studies for pleural mesothelioma.

Clinical outcomes of left upper segmentectomy vs. lobectomy for early non-small-cell lung cancer: a nationwide database study in Japan.

PURPOSE: Given that left upper lobe and right upper and middle lobes share a similar anatomy, segmentectomy, such as upper division and lingulectomy, should yield identical oncological clearance to left upper lobectomy. We compared the prognosis of segmentectomy with that of lobectomy for early stage non-small-cell lung cancer (NSCLC) in the left upper lobe. METHODS: We retrospectively examined 2115 patients who underwent segmentectomy or lobectomy for c-stage I (TNM 8th edition) NSCLC in the left upper lobe in 2010. We compared the oncological outcomes of segmentectomy (n = 483) and lobectomy (n = 483) using a propensity score matching analysis. RESULTS: The 5-year recurrence-free and overall survival rates in the segmentectomy and lobectomy groups were comparable, irrespective of c-stage IA or IB. Subset analyses according to radiological tumor findings showed that segmentectomy yielded oncological outcomes comparable to those of lobectomy for non-pure solid tumors. In cases where the solid tumor exceeded 20 mm, segmentectomy showed a recurrence-free survival inferior to that of lobectomy (p = 0.028), despite an equivalent overall survival (p = 0.38). CONCLUSION: Segmentectomy may be an acceptable alternative to lobectomy with regard to the overall survival of patients with c-stage I NSCLC in the left upper lobe.

Features of anaplastic lymphoma kinase rearrangement in early-stage lung cancer: Analysis of a nationwide Japanese database.

BACKGROUND AND OBJECTIVES: Anaplastic lymphoma kinase (ALK) rearrangement is a representative driver mutation in lung cancer. However, the biology of early-stage ALK-rearranged lung cancer remains unclear. We aimed to assess the clinicopathological features, prognostic implications, and influence of ALK rearrangement on the postoperative course in surgically resected lung cancer. METHODS: We retrospectively analyzed data from the Japanese Joint Committee of Lung Cancer Registry database. Of the 12 730 patients with lung adenocarcinoma, 794 (6.2%) were tested for ALK rearrangement and were included. RESULTS: ALK rearrangements were detected in 76 patients (10%). The 5-year overall survival (OS) rate was significantly higher in the ALK rearrangement-positive group than in the ALK rearrangement-negative group (p = 0.030). Multivariable analysis revealed that ALK rearrangement was an independent prognostic factor for improved OS (hazard ratio, 0.521; 95% confidence interval, 0.298-0.911; p = 0.022). Regarding the postrecurrence state, there was no difference in the initial recurrence sites between both groups. Administration of ALK-tyrosine kinase inhibitors (TKIs) improved postrecurrence survival in any treatment lines. CONCLUSION: In one of the largest national surveys, ALK rearrangement was associated with improved long-term outcomes in surgically resected patients. ALK-TKIs may be an important treatment strategy for ALK rearrangement-positive lung adenocarcinoma in the postrecurrence state.

Is adjuvant chemotherapy for completely resected p-stage IA (>2 cm) and stage IB non-small-cell lung cancer beneficial for elderly patients? A large, retrospective cohort study based on real-world data from Japan.

OBJECTIVE: The efficacy of tegafur-uracil as adjuvant chemotherapy for patients with completely resected stage I non-small-cell lung cancer is proven; however, its efficacy for elderly patients remains unclear. Herein, we evaluated the effectiveness of adjuvant chemotherapy for elderly patients with completely resected stage I non-small-cell lung cancer based on real-world Japanese data using propensity score matching. METHODS: This retrospective study extracted data from a nationwide registry study, performed in 2016, on patients ≥75 years who underwent lobectomy with mediastinal nodal dissection for non-small-cell lung cancer in 2010 and were diagnosed with p-stage IA (>2 cm) or stage IB non-small-cell lung cancer. We classified the 1294 patients into two groups-Group A, postoperative adjuvant chemotherapy (n = 295, 22.8%) and Group N, no adjuvant chemotherapy (n = 999, 77.2%)-and analyzed differences in postoperative overall survival between groups. RESULTS: Group A showed no advantage in overall survival over Group N as a whole (hazard ratio: 0.824 [95% confidence interval: 0.631-1.076]), in p-stage IA (hazard ratio: 0.617 [95% confidence interval: 0.330-1.156]) and in p-stage IB (hazard ratio: 0.806 [95% confidence interval: 0.597-1.088]) subsets. Even after propensity score matching, Group A showed no significant advantage in overall survival over Group N as a whole (hazard ratio: 0.975 [95% confidence interval: 0.688-1.381]), in p-stage IA (hazard ratio: 1.390 [95% confidence interval: 0.539-3.586]) and in p-stage IB (hazard ratio: 0.922 [95% confidence interval: 0.633-1.343]). CONCLUSIONS: adjuvant chemotherapy for completely resected p-stage IA (>2 cm) and stage IB non-small-cell lung cancer showed no benefit for recommendation for elderly patients; considering the risk of adverse events, we do not recommend adjuvant chemotherapy for elderly patients.

Postoperative cerebral infarction and arrhythmia after pulmonary lobectomy in Japan: a retrospective analysis of 77,060 cases in a national clinical database.

PURPOSE: To investigate the incidence of postoperative cerebral infarction after curative lobectomy, its association with the type of lobectomy, and how postoperative new-onset arrhythmia contributes to postoperative cerebral infarction. METHODS: The subjects of this analysis were 77,060 patients who underwent curative lobectomy for lung cancer between 2016 and 2018 according to the National Clinical Database. Incidences of postoperative cerebral infarction and postoperative new-onset arrhythmia were analyzed. Moreover, mediation analysis was performed to evaluate the causal pathway between postoperative new-onset arrhythmia and postoperative cerebral infarction. RESULTS: Postoperative cerebral infarction occurred in 110 (0.7%) patients after left upper lobectomy and in 85 (0.7%) patients after left lower lobectomy. Left upper lobectomy and left lower lobectomy were associated with a higher likelihood of postoperative cerebral infarction than right lower lobectomy. Left upper lobectomy was the strongest independent predictor of postoperative new-onset arrhythmia. However, in the mediation analysis, the odds ratio for cerebral infarction did not change after the addition of the factor of postoperative new-onset arrhythmia. CONCLUSION: Cerebral infarction occurred significantly more often not only after left upper lobectomy, but also after left lower lobectomy. Postoperative new-onset arrhythmia was less likely to be related to cerebral infarction after left upper lobectomy.

The consecutive impact of COVID-19 on thoracic surgical procedures in Japan: an analysis of data from the National Clinical Database.

PURPOSE: The current study was designed to analyze the impact of the COVID-19 pandemic on general thoracic surgeries in Japan. METHODS: Changes in surgeries for lung cancer and metastatic lung tumors were evaluated based on National Clinical Database data regarding cancer screening. RESULTS: In 2021, surgeries for primary lung cancer increased by 3.4% compared to 2020, which, given the increase from 2014 to 2019, indicates an overall 11.1% decrease. In contrast, surgeries for metastatic lung tumors in 2021 decreased by 5.8% compared to 2020, which, given the increase from 2014 to 2020, indicates an overall 9.2% decrease. Half of the primary diseases for metastatic lung tumor were cases of colorectal cancer. Low anterior resection procedures in 2020 decreased by 5.5% compared to 2019. Lung and colon cancer screening examinees in 2021 were increased compared to 2020; however, they still showed respective decreases of 11% and 9.0% compared to 2019. CONCLUSIONS: Surgeries for primary lung cancer still decreased substantially during the COVID-19 pandemic. The continued stagnation of screening was responsible for this decrease. Surgeries for metastatic lung tumors decreased profoundly, and the decrease in screening for primary tumors was responsible for this reduction. Our findings emphasize the significance of maintaining cancer screening efforts, even during a pandemic.

[Retrograde S(9+)10 Segmentectomy without Interlobar Fissurelectomy].

BACKGROUNDS: With increase of patients with a small-sized lung cancer, there is an increasing need for minimally invasive lung segmentectomy that can preserve respiratory function. We perform S(9+)10 segmentectomy with retrograde dissection of the pulmonary vein, bronchus, pulmonary artery, in order, without interlober fissurelectomy and staple dissection of the peripheral lung parenchyma. METHODS: Seven patients who underwent retrograde S(9+)10 segmentectomy between June, 2021 and May, 2022 in our hospital were retrospectively reviewed. RESULTS: No patient was converted to the open thoracotomy, without any complications including prolonged air leakage. The average operation time was 171 minutes( range 125 to 221), amount of bleeding was 25 ml( range 0 to 75). Median duration of chest tube insertion was 4 days( range 3 to 6), length of stay after surgery was 6 days (range 5 to 9). Pathologic stage showed pT1mi in 3 patients, pT1a in 3 patients, pT2a in 1 patient. No local recurrence was seen at this time. CONCLUSIONS: Retrograde S(9+)10 segmentectomy is feasible and facilitates interlobar procedure at the time of repeated segmentectomy or completion lobectomy.

The prognostic impact of lung adenocarcinoma predominance classification relating to pathological factors in lobectomy, the Japanese Joint Committee of Lung Cancer Registry Database in 2010.

OBJECTIVE: We studied the prognosis and clinicopathological background of lung adenocarcinoma predominance among patients who underwent lobectomy using data from the Japanese Joint Committee of Lung Cancer Registry. METHODS: Two thousand eight hundred sixty-three cases were extracted. Recurrence free survival (RFS) rates, overall survival (OS) rates and clinicopathological factors and epidermal growth factor receptor (EGFR) mutation status were examined. RESULTS: Median follow-up period was 65.5 months. Adenocarcinoma predominance was sub-grouped according to OS and RFS rate. In pathological stage I, 5-year RFS and OS rates were respectively 92.2% and 95.8% in group A (adenocarcinoma-in-situ + minimally invasive adenocarcinoma), 89.3% and 92.1% in group B (lepidic), 79.2% and 89.7% in group C (papillary + acinar + variants) and 69.0% and 79.0% in group D (solid + micropapillary). In pathological stage II + IIIA, they were, 43.6% and 72.4% in B, 39.5% and 66.9% in C and 31.0% and 53.7% in D. Group D showed significant worst outcome both in stage I and II + IIIA. Up stage rate from clinical stage I to pathological stage II + IIIA was 0.0%, 3.7%, 15.9% and 33.3%. The frequency of lymph-vessel, vascular, pleura invasion and positive EGFR mutation were 0.0%, 0.0%, 0.0% and 57.1% in group A, 15.6%, 10.0%, 12.1% and 55.1% in B, 36.6%, 31.8%, 29.7% and 44.9% in C, 50.2%, 57.8%, 38.9% and 21.3% in D. In group D, lymph-vessel, vascular and pleura invasion were most, EGFR mutation was least frequent not only in pathological stage I but also stage II + IIIA. In multivariate analysis, age, pathological stage, vascular invasion, and group D were independent factors affected RFS and OS. CONCLUSION: Limited to lobectomy cases, solid + micropapillary was independent prognostic factor both in early and locally advanced stage. Its malignant degree was related to the frequency of pathological invasive factors and EGFR mutation status.

A risk model for prolonged air leak after lobectomy using the National Clinical Database in Japan.

PURPOSE: The objective of our study was to develop a clinical prediction model for prolonged air leak (PAL) after lobectomy for lung cancer using preoperative variables in a large patient dataset from the National Clinical Database (NCD) in Japan. METHODS: The preoperative characteristics of 57,532 and 30,967 patients who had undergone standard lobectomy for lung cancer were derived from the 2014 to 2015 and 2016 NCD datasets, respectively. PAL was defined as air leak persisting ≥ 7 days postoperatively or requiring postoperative interventional treatment, such as pleurodesis or reoperation. Risk models were developed from the 2014 to 2015 dataset and validated using the 2016 dataset. When performing model derivation, the least absolute shrinkage and selection operator (LASSO) method were applied for parameter selection. RESULTS: The rate of PAL was 4.5% in 2014-2015 and 5.3% in 2016. The age, sex, body mass index, comorbid interstitial pneumonia, smoking habits, forced expiratory volume in 1 s, tumor histology, multiple lung cancer, and tumor location were selected as important variables for PAL. Our risk model for predicting PAL was fair with a concordance index of 0.6895. CONCLUSION: The LASSO-based risk model for PAL after lobectomy provided important preoperative variables for PAL and risk weighting for each variable.

No association between hospital volume and short-term outcomes of some common surgeries: a retrospective cohort study based on a Japanese nationwide database.

PURPOSE: Centralization of high-risk surgeries has become a widespread strategy. However, whether or not the hospital volume affects the outcomes of common surgeries remains unclear. This study explored the association between hospital volume and short-term outcomes of common surgeries, as represented by appendectomy, cholecystectomy, and pneumothorax surgery, by analyzing data from a Japanese nationwide database. METHODS: All hospitals were categorized into four groups (very low-, low-, high-, and very high-volume) according to the annual hospital volume of all gastrointestinal surgeries or all respiratory surgeries in 2017. Patient demographic data and surgical outcomes were evaluated across hospital volume categories. RESULTS: We analyzed 2392 facilities which performed 771,182 gastrointestinal surgeries, and 992 facilities which performed 98,656 respiratory surgeries. Short-term outcomes of patients who underwent appendectomy (n = 50,568), cholecystectomy (n = 104,262), and pneumothorax surgery (n = 11,723) were evaluated. The incidences of postoperative complications, reoperation, and readmission were similar among the groups. Multivariable logistic regression analyses revealed hospital volume to have no association with these short-term outcomes. CONCLUSION: Analyses of a Japanese nationwide database revealed that the hospital volume was not associated with short-term outcomes of appendectomy, cholecystectomy, and pneumothorax surgery. These common surgical procedures may not require centralization into high-volume hospitals.

Clinical features and outcomes of patients with stage I multiple primary lung cancers.

The number of patients with multiple primary lung cancers (MPLC) is rising. We studied the clinical features and factors related to outcomes of MPLC patients using the database of surgically resected lung cancer (LC) cases compiled by the Japanese Joint Committee of Lung Cancer Registry. From the 18 978 registered cases, 9689 patients with clinical stage I non-small-cell lung cancer who achieved complete resection were extracted. Tumors were defined as synchronous MPLC when multiple LC was simultaneously resected or treatment was carried out within 2 years after the initial surgery; metachronous MPLC was defined as second LC treated more than 2 years after the initial surgery. Of these cases, 579 (6.0%) were synchronous MPLC and 477 (5.0%) metachronous MPLC, with 51 overlapping cases. Female sex, nonsmoker, low consolidation-tumor ratio (CTR), and adenocarcinoma were significantly more frequent in the synchronous MPLC group, whereas patients with metachronous MPLC had higher frequencies of male sex, smoker, chronic obstructive pulmonary disease (COPD), and nonadenocarcinoma. There was no significant difference in survival rate between patients with and without synchronous or metachronous MPLC. Age, gender, CTR for second LC, and histological combination of primary and second LC were prognostic indicators for both types of MPLC. Logistic regression analysis showed that female sex, history of malignant disease other than LC, and COPD were risk factors for MPLC incidence. The present findings could have major implications regarding MPLC diagnosis and identification of independent prognostic factors, and provide valuable information for postoperative management of patients with MPLC.

Nondestructive Quantitative Analysis of Difficult-to-Measure Radionuclides 107Pd and 99Tc.

Considering the expanding demand for nuclear waste management of the spent nuclear fuel materials in near future, a nondestructive analytical scheme applicable to one of the most difficult-to-measure nuclides 107Pd, which emits no decay γ-rays and whose half-life is too long to be decayed out during a human lifetime, was designed. The scheme consists of a sophisticated instrument capable of the detection of γ-rays by Ge detectors coupled with time-of-flight measurement of neutrons and a high-intensity pulsed neutron beam and can simultaneously perform time-of-flight-coupled prompt γ-ray analysis (TOF-PGA) as well as PGA and neutron resonance capture analysis (NRCA). The analytical capability for simulated samples of the Tc-platinum group metals (Tc-PGMs) obtained by the group-partitioning process of spent nuclear fuels, which contain not only 107Pd but also 99Tc and other difficult-to-measure fission products, was evaluated. It was confirmed that although PGA and NRCA can accurately analyze both nuclides in individual, single substances, only TOF-PGA can analyze 107Pd as well as 99Tc in the Tc-PGM-simulated sample. The TOF-PGA measurement technique can be widely used for the nondestructive analysis of 107Pd and 99Tc in nuclear wastes.

Certified thoracic surgeons in Japan: a national database survey on risk-adjusted mortality associated with lung resection.

PURPOSE: We investigated the association between the number of certified general thoracic surgeons (GTSs) and the mortality after lung cancer surgery, based on the data from the National Clinical Database (NCD). METHODS: We analyzed the characteristics and operative and postoperative data of 120,946 patients who underwent lung cancer surgery in one of the 905 hospitals in Japan. The number of GTSs in each hospital was categorized as 0, 1-2, or 3 or more. Multivariable analysis was applied to adjust the patients' preoperative risk factors, as identified in a previous study. We calculated 95% confidence intervals (CI) for the mortality rate based on the odds ratios (ORs). RESULTS: The patients' characteristics were distributed almost uniformly regardless of the number of GTSs. Crude mortality according to the number of GTSs of 0, 1-2, or 3 or more was 0.9%, 0.8%, and 0.7%, respectively (p = 0.03). However, after adjustment, the ORs for 1-2 and 3 or more GTSs (reference: 0) were 0.86 (p = 0.23, 95% CI: 0.67-1.10) and 0.84 (p = 0.18, 95% CI: 0.64-1.09), respectively. The number of GTSs did not have a significant association with mortality. Similar results were observed for patients in the lobectomy cohort. CONCLUSION: Low surgical mortality was consistent, regardless of the number of GTSs in each hospital.

[Metaplastic Thymoma Underwent Surgery:Report of a Case].

Metaplastic thymoma is a rare histologic variant of thymic epithelial tumors and is characterized by a biphasic growth pattern. We herein report the case of 44-year-old woman who underwent surgery for metaplastic thymoma. Computed tomography scan revealed a well-circumscribed mediastinal tumor: 56 mm in diameter with homogenous enhancement. The tumor was suspected to be a non-invasive thymoma, and thymomectomy with resection of the surrounding thymus was performed using thoracoscopy. The resected tumor measured 60 mm and was grossly well-encapsulated. The cut surface was gray to white and homogenous. Microscopically, the epithelial components took the form of an anastomosing nest to broad trabeculae intertwining with the bundle of spindle cells. Mitosis was not found and the Ki-67 index was < 1%. Cytokeratin 5/6 was strongly positive in the epithelial components composed of polygonal cells. Terminal deoxynucleotidyl transferase positive immature T cells were not observed. Based on these pathologic findings, the tumor was identified as metaplastic thymoma.

[The Outcome of Second Anatomical Pulmonary Resection for Ipsilateral Metachronous Lung Cancer].

INTRODUCTIONS: When the first intervention for lung cancer is anatomical resection, the ipsilateral repeat anatomical resection for metachronous second lung cancer becomes technically challenging. Herein, we report the outcomes of second anatomical pulmonary resection for ipsilateral metachronous lung cancer at our institution. SUBJECTS: Sixteen consecutive patients[ 10 men and 6 women, average age 70( range 59~81) years] were reviewed in this retrospective study. These patients underwent ipsilateral repeat anatomical resection for metachronous second lung cancer between 2009 and 2020. RESULTS: All case required right-sided lung resections. The previous interventions of patients included upper lobectomy, lower lobectomy, middle lobectomy, S2 segmentectomy, and S6 and S10a segmentectomy in 9, 4, 1, 1, and 1 case, respectively. The second surgical interventions were middle lobectomy, S6 segmentectomy, upper lobectomy, lower lobectomy, S1 segmentectomy, and S2 segmentectomy, in 6, 4, 2, 2, 1, and 1 case, respectively. Postoperative complications occurred in three patients. The median follow-up period was 53.5 months. Three patients died during the follow-up period. Of the 13 patients still alive, 6 had recurrence. The five-year overall survival rate was 80%. CONCLUSIONS: Although only a few cases were assessed, the prognosis after second anatomical pulmonary resection for ipsilateral metachronous lung cancer at our institution was satisfactory.

[Completion Pneumonectomy for the Recurrence of Lung Cancer].

INTRODUCTIONS: The morbidity and mortality after completion pneumonectomy (CP) are reportedly high. We, herein, report the outcomes of CP at our institution. SUBJECTS: Nine consecutive patients [7 men and 2 women, average age of 72 years(range 44~84 years)] who underwent CP for recurrence of lung cancer during 2012~2018 were retrospectively reviewed. RESULTS: Right-sided sleeve CP was performed in two cases and left-sided CP in seven cases. The indications for surgery were lymph node metastasis of the cancer, pulmonary metastasis, and bronchial stump recurrence in 4, 3, and 2 cases, respectively. Postoperative complications occurred in six patients. One of the patients who underwent right sleeve pneumonectomy developed bronchopleural fistula and died 68 days after the surgery. The mean follow-up period was 33 months, and four patients died during follow-up. Of the 5 patients still alive, 4 had no recurrence and 1 had recurrence in the stump of the main bronchus. The five-year overall survival rate was 78%. CONCLUSIONS: Although only few cases were assessed, the prognosis after CP at our institution was relatively good.

Reciprocal expression of trefoil factor-1 and thyroid transcription factor-1 in lung adenocarcinomas.

Molecular targeted therapies against EGFR and ALK have improved the quality of life of lung adenocarcinoma patients. However, targetable driver mutations are mainly found in thyroid transcription factor-1 (TTF-1)/NK2 homeobox 1 (NKX2-1)-positive terminal respiratory unit (TRU) types and rarely in non-TRU types. To elucidate the molecular characteristics of the major subtypes of non-TRU-type adenocarcinomas, we analyzed 19 lung adenocarcinoma cell lines (11 TRU types and 8 non-TRU types). A characteristic of non-TRU-type cell lines was the strong expression of TFF-1 (trefoil factor-1), a gastric mucosal protective factor. An immunohistochemical analysis of 238 primary lung adenocarcinomas resected at Jichi Medical University Hospital revealed that TFF-1 was positive in 31 cases (13%). Expression of TFF-1 was frequently detected in invasive mucinous (14/15, 93%), enteric (2/2, 100%), and colloid (1/1, 100%) adenocarcinomas, less frequent in acinar (5/24, 21%), papillary (7/120, 6%), and solid (2/43, 5%) adenocarcinomas, and negative in micropapillary (0/1, 0%), lepidic (0/23, 0%), and microinvasive adenocarcinomas or adenocarcinoma in situ (0/9, 0%). Expression of TFF-1 correlated with the expression of HNF4-α and MUC5AC (P < .0001, P < .0001, respectively) and inversely correlated with that of TTF-1/NKX2-1 (P < .0001). These results indicate that TFF-1 is characteristically expressed in non-TRU-type adenocarcinomas with gastrointestinal features. The TFF-1-positive cases harbored KRAS mutations at a high frequency, but no EGFR or ALK mutations. Expression of TFF-1 correlated with tumor spread through air spaces, and a poor prognosis in advanced stages. Moreover, the knockdown of TFF-1 inhibited cell proliferation and soft-agar colony formation and induced apoptosis in a TFF-1-high and KRAS-mutated lung adenocarcinoma cell line. These results indicate that TFF-1 is not only a biomarker, but also a potential molecular target for non-TRU-type lung adenocarcinomas.

Current status of surgery for clinical stage IA lung cancer in Japan: analysis of the national clinical database.

PURPOSE: As the number of cases of early lung cancer in Japan grows, an analysis of the present status of surgical treatments for clinical stage IA lung cancer using a nationwide database with web-based data entry is warranted. METHODS: The operative and perioperative data from 47,921 patients who underwent surgery for clinical stage IA lung cancer in 2014 and 2015 were obtained from the National Clinical Database (NCD) of Japan. Clinicopathological characteristics, surgical procedure, mortality, and morbidity were analyzed, and thoracotomy and video-assisted thoracic surgery (VATS) were compared. RESULTS: The patients comprised 27,208 men (56.8%) and 20,713 women (43.2%); mean age, 69.3 years. Lobectomy was performed in 64.8%, segmentectomy in 15.2%, and wedge resection in 19.8%. The surgical procedures were thoracotomy in 12,194 patients (25.4%) and a minimally invasive approach (MIA) in 35,727 patients (74.6%). MIA was divided into VATS + mini-thoracotomy (n = 13,422, 28.0%) and complete VATS (n = 22,305, 46.5%). The overall postoperative mortality rate was 0.4%, being significantly lower in the MIA group than in the thoracotomy group (0.3% vs 0.8%, P < 0.001). CONCLUSIONS: Our analysis of data from the NCD indicates that MIA has become the new standard treatment for clinical stage IA lung cancer.

[Desmoid Tumor Treated by Wide Resection of the Anterior Chest Wall].

Desmoid tumors are rare mesenchymal proliferative tumors that are highly invasive but lack metastatic potential. We report the case of a 72-year-old man with a desmoid tumor arising from the anterior chest wall which invaded neighboring organs extensively. The patient complained of dyspnea on exertion and appetite loss and was referred to our hospital. Chest computed tomography revealed an anterior chest wall tumor 12 cm in diameter adjacent to the right lung, diaphragm, and sternum. An ultrasound-guided biopsy was conducted, and the tumor was diagnosed as a desmoid tumor. He underwent right-sided anterior chest wall resection with combined resection of the right lung, diaphragm, and sternum body. The chest wall defect was reconstructed using an expanded polytetrafluorethylene mesh (dualmesh). Although initial active surveillance has recently been recommended for asymptomatic patients with non-progressing desmoid tumors, our patient underwent resection because of his symptoms.

Mucin 21 is a key molecule involved in the incohesive growth pattern in lung adenocarcinoma.

Decreased cell adhesion has been reported as a significant negative prognostic factor of lung cancer. However, the molecular mechanisms responsible for the cell incohesiveness in lung cancer have not yet been elucidated in detail. We herein describe a rare histological variant of lung adenocarcinoma consisting almost entirely of individual cancer cells spreading in alveolar spaces in an incohesive pattern. A whole exome analysis of this case showed no genomic abnormalities in CDH1 or other genes encoding cell adhesion molecules. However, whole mRNA sequencing revealed that this case had an extremely high expression level of mucin 21 (MUC21), a mucin molecule that was previously shown to inhibit cell-cell and cell-matrix adhesion. The strong membranous expression of MUC21 was found on cancer cells using mAbs recognizing different O-glycosylated forms of MUC21. An immunohistochemical analysis of an unselected series of lung adenocarcinoma confirmed that the strong membranous expression of MUC21 correlated with incohesiveness. Thus, MUC21 could be a promising biomarker with potential diagnostic and therapeutic applications for lung adenocarcinoma showing cell incohesiveness.