Radiological unilateral pleuroparenchymal fibroelastosis as a notable late complication after lung cancer surgery: incidence and perioperative associated factors.

OBJECTIVES: Pleuroparenchymal fibroelastosis (PPFE) is a rare idiopathic interstitial pneumonia characterized by pleural-parenchymal involvement, predominantly in the upper lobes. Unilateral upper lung field pulmonary fibrosis (upper-PF) that is radiologically consistent with PPFE reportedly develops after lung cancer surgery in the operated side and presents many clinical characteristics in common with PPFE. However, the incidence and perioperative associated factors remain unclear. METHODS: All consecutive patients with lung cancer resected completely from 2008 to 2016 were investigated retrospectively. Pre-/postoperative characteristics were compared between patients with and without unilateral upper-PF. Cumulative incidence curves were estimated using competing risk analysis. RESULTS: Among the 587 included patients, 25 patients (4.3%) were diagnosed as unilateral upper-PF. The 3-, 5- and 10-year cumulative incidence of unilateral upper-PF was 2.3%, 3.3% and 5.3%, respectively. In multivariable analysis, male sex, presence of a pulmonary apical cap, lobar resection and low % vital capacity (%VC < 80%) were independent perioperative associated factors. The 10-year cumulative incidence was 6.3% in patients treated with lobar resection, 8.0% in male patients, 10.3% in patients with pulmonary apical cap and 14.5% in patients with low %VC. Postoperative pleural effusion at 6 months after surgery was much more common in the patients who later developed unilateral upper-PF (96.0% vs 24.2%). This pleural effusion persisted and was accompanied thereafter by pleural thickening and subpleural pulmonary fibrosis. During the clinical courses of 25 patients with unilateral upper-PF, 18 patients presented symptoms related to upper-PF and 6 patients died. CONCLUSIONS: Unilateral upper-PF is an occasional but under-recognized late complication after lung cancer surgery.

Impact of the first surge of the coronavirus disease pandemic on general thoracic surgery practices in Kanagawa: a questionnaire survey by the Kanagawa General Thoracic Surgical Study Group.

OBJECTIVES: The first surge in severe acute respiratory syndrome coronavirus 2 infection had a significant impact on health care institutions. Understanding how the pandemic affected general thoracic surgery would provide valuable data for establishing a health care protocol for upcoming surges. METHODS: A questionnaire survey on coronavirus disease-related patient statistics and health care was conducted between February 2020 and June 2020 across 14 facilities affiliated with the Kanagawa General Thoracic Surgery Study Group. RESULTS: The average number of newly referred patients from February to June 2020 was 65% of that during the same period in 2019. Six facilities placed restrictions on medical care services, among which four restricted surgeries. At all institutions and those placed on surgical restriction, the total number of surgeries under general anesthesia was 92% and 78%, the total number of primary lung cancers was 94% and 86%, and the total number of surgeries for pneumothorax was 71% and 77% of that in the preceding year, respectively. Infection control and insufficient resources of the medical material were the most influential factors impacting the medical institutions' decision to restrict the services provided. CONCLUSIONS: Restrictions on surgery had a significant impact on the care provided by general thoracic surgery departments. To avoid patient inconvenience, establishing a collaborative system that refers patients to operational medical institutions in case of medical treatment restrictions may be useful.

Fungus ball removal with video-cavernoscopy for complex aspergilloma.

OBJECTIVE: Complete resection with a clear margin is the only curative treatment for pulmonary aspergilloma. This requires a high-level technique, especially for complex aspergilloma (CA), because of patient conditions and wide dense adhesions. Fungus ball removal is used palliatively to control hemoptysis, rather than as a radical procedure, and may be performed using video-cavernoscopy as a simple and repeatable method. In this study, we examined this approach as an alternative treatment for CA. METHODS: Eight cases of fungus ball removal with video-cavernoscopy (video-cavernoscopic removal) treated at our center were retrospectively reviewed. The patient characteristics and surgical outcomes were compared with those of patients treated with one-stage radical surgery. RESULTS: There were 8 subjects (7 males, 1 female; median age 65 years) in the video-cavernoscopic removal group and 25 subjects (19 males, 6 females; median age 56 years) in the one-stage radical surgery group. The video-cavernoscopic removal group had a higher rate of emphysematous lung (p = 0.001), a lower body mass index (p = 0.039), and a lower percent vital capacity (p = 0.027). All cases in this group had preoperative hemoptysis that ceased after the procedure. Video-cavernoscopic removal was less invasive based on a shorter operative time (p = 0.000), less blood loss (p = 0.002), and a lower Common Terminology Criteria for Adverse Events grade (p = 0.023). However, four cases in this group (50%) relapsed with a median disease-free survival period of 471.5 days. CONCLUSIONS: Fungus ball removal with video-cavernoscopy is a simple technique for the prevention and control of massive hemoptysis that may be an alternative treatment for CA.

Intermediate bronchial kinking after right upper lobectomy for lung cancer.

BACKGROUND: Bronchial kinking after lung lobectomy is likely, whereas that of the intermediate bronchus after right upper lobectomy is often not recognized. The aim of this study was to examine the clinical implications of this condition. METHODS: One-hundred cases of right upper lobectomy for primary lung cancer were reviewed. The cases were divided into groups with intermediate (group A) and non-intermediate (group B) bronchial kinking, and the patient characteristics and postoperative outcomes were compared. The remaining lower lobe deformation was also evaluated using the angle formed by the intrathoracic tracheal line and posterior fissure on reconstructed sagittal computed tomography. RESULTS: There were 23 cases in group A which had a higher rate of bronchial calcification, older age, and female sex, whereas and smoking and pulmonary emphysema were less frequent. Three cases in group A had respiratory symptoms such as wheezing and respiratory noise, while only one case of middle lobe atelectasis was found in group B. In multivariate analysis, upper mediastinal lymph node dissection was an independent factor for non-intermediate bronchial kinking. The lower lobe was significantly more expanded in group A than in group B. CONCLUSIONS: Intermediate bronchial kinking correlates with postoperative respiratory symptoms and was less likely after upper mediastinal lymph node dissection.

A spectrum of Thymic mucosa-associated lymphoid tissue lymphoma and Thymic amyloidosis in the patient with Auto immune disease: a case series.

BACKGROUND: The thymus is associated with an immunodeficient status, autoimmune disease (AD), and the common thymic tumor, thymoma. We encountered two rare thymic tumors, thymic mucosa-associated lymphoid tissue (MALT) lymphoma and localized thymic amyloidosis, both in the presence of Sjögren's syndrome (SjS). This suggests a possible link between rare thymic tumors and SjS. Therefore, we reviewed cases of thymic tumors to examine the spectrum of these tumors in patients with AD. METHODS: The clinical information of thymic amyloidosis and MALT lymphoma surgically treated at Kanagawa Cardiovascular and Respiratory Center, and Yokohama City University Hospital from January 2010 to December 2019 were reviewed. The correlation between resected thymic tumors at same period and ADs were also investigated. RESULTS: There were 5 cases of thymic amyloidosis and MALT lymphoma. ALL cases had coexistent ADs (4 SjS, 1 SSc). The median age was 66 (38-76) year-old, and 4 of the patients were female. Three cases had already diagnosed as ADs before detection of tumors. Only SSc case was received preceding steroid medication. Two cases diagnosed as SjS at the same time of the operation. The median maximum tumor diameter was 70 mm. On chest computed tomography (CT), tumors contained solid part and some cystic part at various rated. Calcification was recognized with appearance of amyloid deposition. All patients were surgically treated with total thymectomy and they are alive without recurrence. At the same period, there were 163 resected thymic tumors, including amyloidosis, MALT lymphoma, thymoma, thymic cancer, neuroendocrine tumor and so on. Among them, nine patients (5.5%) had ADs. There was a correlation between ADs and thymic MALT lymphoma/amyloidosis (P<0.001). CONCLUSIONS: We propose a process for tumorigenesis of thymic MALT lymphoma and amyloidosis. Underlying AD causes persistent and chronic inflammatory reactions. In this theory, ADs, especially SjS, might be important underlying conditions in formation of rare tumors. When the clinician encounters a patient with AD, routine chest CT is recommended and may provide thymic tumors. Conversely, in case of mediastinum tumor, screening test for AD is also recommended.

A case of intrathoracic desmoid tumor with pulmonary Mycobacterium abscessus disease.

A 68-year-old man who was on treatment for pulmonary Mycobacterium avium complex complained a worsening of sputum. Although he archived negative sputum culture two months ago, sputum culture tests revealed the newly isolation of Mycobacterium abscessus repeatedly. Chest computed tomography showed newly-appeared extra-pulmonary mass lesion in contact with a cyst at the bottom of his right lung. From the results of contrast-enhanced magnetic resonance imaging, we first suspected loculated pleural effusion due to Mycobacterium abscessus infection. A thoracoscopic examination was performed as the right pneumothorax developed, and the pleural lesion was successfully resected and diagnosed as an intrathoracic desmoid tumor. Intrathoracic desmoid tumor is very rare, and this is the first report of a case with pulmonary Mycobacterium abscessus disease.

A prophylaxis study of acute exacerbation of interstitial pneumonia after lung cancer surgery.

INTRODUCTION: Acute exacerbation of interstitial pneumonia (AE-IP) is a lethal complication after lung surgery. We conducted a prospective, multi-institutional phase II trial to assess the efficacy and safety of prophylactic measures. METHOD: Patients with lung cancer with dorsal subpleural fibrotic changes occupying three or more segments of both lower lobes and planned anatomical lung resection were enrolled. Prior to surgery, patients received a 125-mg bolus injection of methylprednisolone and continuous intravenous infusion of sivelestat sodium hydrate (sivelestat) for 2 days. RESULTS: Sixty-nine patients were analysed. Preoperative high-resolution computed tomography (HRCT) showed 37 (53.6%) cases presented with usual interstitial pneumonia (UIP) and possible UIP pattern. There were 60 lobectomies and 9 segmentectomies. Thirty-eight cases were in clinical stage I. No adverse events associated with prophylaxis were observed. There were four cases of AE-IP (5.8%), higher than the expected 2.0%. Three of the four cases showed inconsistencies with the UIP pattern in preoperative HRCT and were pathologically diagnosed as UIP. All patients died of respiratory failure. Overall, 89.9% were diagnosed as idiopathic interstitial pneumonias; UIP was found in 48 patients (69.6%). Severe post-operative complications occurred in 11.6% of the cases. There were 35 deaths, 17 cases of lung cancer and 11 cases related to interstitial pneumonias. The overall survival rate at 3 years was 41.8% of the total and 47.2% of cases with clinical stage I. CONCLUSIONS: Perioperative use of sivelestat and low-dose methylprednisolone in patients with anatomical lung resection was safe but did not prove to be a prophylactic effect for AE-IP.

Computer-aided Quantification of Pulmonary Fibrosis in Patients with Lung Cancer: Relationship to Disease-free Survival.

Background Interstitial lung abnormalities (ILAs) are present at CT in about 10% of individuals undergoing lung cancer screening. The relationship between histologic findings of ILAs and their influence on patient prognosis remains unknown. Purpose To evaluate the percentage of ILAs at preoperative CT, as measured by radiologists and a computer-aided detection (CAD) software, as a predictor of disease-free survival in patients with lung cancer. Materials and Methods This retrospective study evaluated 217 consecutive patients who underwent complete resection of lung cancer from April 2010 to December 2015. Two radiologists, blinded to the patients' clinical information, scored percentage fibrosis extent and determined whether ILAs and the usual interstitial pneumonia (UIP) pattern were present. They assessed ILA progression at follow-up CT. Two pathologists determined the presence of an UIP pattern. Percentage fibrosis extent was also measured by using CAD. Binary logistic regression analysis was performed to determine whether the CAD percentage fibrosis extent was associated with ILA at CT. Multivariable Cox regression analysis was used to evaluate the significance of CAD percentage fibrosis extent as a predictor of prognosis. Results The radiologists classified 47 patients with ILAs and 24 patients with a UIP pattern at chest CT. The pathologists detected a UIP pattern in 25 patients. CT abnormalities showed progression over a 2-year period in all patients with histologic evidence of UIP. After adjustment for age, sex, and smoking index, the CAD percentage fibrosis extent was independently associated with ILA (odds ratio: 3.1; 95% confidence interval [CI]: 2.1, 4.7; P < .001). After adjustment for age, forced expiratory volume in 1 second (percentage predicted) radiologist-assessed percentage fibrosis extent, and pathologic stage, CAD percentage fibrosis extent was independently associated with worse disease-free survival (hazard ratio: 1.3; 95% CI: 1.1, 1.6; P < .001). Conclusion Greater computer-aided detection percentage fibrosis extent at preoperative CT independently predicted worse disease-free survival in patients with lung cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Goo in this issue.

Unique expression profiles of mucin proteins in interstitial pneumonia-associated lung adenocarcinomas.

In order to clarify idiopathic interstitial pneumonia (IIP)-associated lung adenocarcinoma (LADC), we herein focused on the expression profiles of mucin proteins, the most common cellular differentiation markers. The expression of the mucin (MUC) 1, MUC2, MUC3B, MUC4, MUC5AC, MUC5B, MUC6, MUC7, MUC9, and MUC21 proteins was examined immunohistochemically and their levels were semi-quantified in 80 IIP-associated LADCs and 106 non-IIP LADCs. LADCs were divided into low and high expressers based on thresholds obtained from the receiver operating characteristic (ROC) curves of each mucin protein. Low expressers of MUC1, MUC7, and MUC21 and high expressers of MUC4, MUC5AC, MUC5B, and MUC9 were dominant in the IIP group. Multivariate analyses confirmed that the correlations between mucin expression profiles and IIP-associated LADCs were independent of putative confounding factors, such as smoking, gender, histological types, and cytological types. Thus, the expression profiles of these mucin proteins significantly differed between the IIP and non-IIP groups. IIP-associated LADCs appear to have unique cellular differentiation features and they may develop through a distinct histogenetic pathway. This is the first study to demonstrate that IIP-associated LADCs have unique mucin expression profiles.

A subpopulation of airway epithelial cells that express hepatocyte nuclear factor 4α - its implication in the development of non-terminal respiratory unit-type lung adenocarcinoma.

A normal counterpart and precancerous lesion that non-terminal respiratory unit (TRU) lung adenocarcinomas (LADCs) develop from have not been clarified. Non-TRU LADCs specifically express hepatocyte nuclear factor 4α (HNF4α). Thus, we have been interested in airway epithelial cells that express HNF4α as the potential precursor of non-TRU LADC. The purposes of the present study are to report the frequency and distribution of HNF4α-expressing cells at the different airway levels, and to investigate the potential significance of the expression of HNF4α in the histogenesis of non-TRU LADC with a special reference to the relationship to bronchiolar metaplasia in idiopathic interstitial pneumonia. We herein identified a minor subpopulation of epithelial cells that express HNF4α in a physiological state. This subpopulation was mainly located in the terminal bronchioles and had the appearance of ciliated cells, which were mutually exclusive from Clara cells and others that strongly expressed thyroid transcription factor 1. Furthermore, the expression of HNF4α was similar in bronchiolar metaplastic lesions and the terminal bronchioles, and some of the metaplastic lesions showed an unequivocally higher frequency and expression level of HNF4α, which was comparable to non-TRU LADC. In summary, this is the first study to describe a subpopulation of ciliated cells that express HNF4α as a potential normal counterpart for non-TRU LADCs and suggests that bronchiolar metaplastic lesions that strongly express HNF4α are a precancerous lesion for non-TRU LADCs.

Bronchoscopy as a Useful Examination for Determining Surgical Treatment Indications in Refractory Mycobacterium avium Complex Lung Disease Patients with Bilateral Lesions.

We herein report three cases of refractory Mycobacterium avium complex (MAC) disease successfully treated surgically despite the MAC lesions being present bilaterally. Of note, although two patients did not present with any respiratory symptom, bronchoscopy clearly revealed a major excretory lesion with a large amount of purulent sputum in all patients. Because an excretory lesion was localized, surgical resection was performed, and the mycobacterial sputum smear became negative in all patients. Bronchoscopy may be a useful examination for detecting major excretory lesions with purulent sputum, which can disseminate to other lobes, and for determining the surgical indications of refractory MAC patients, regardless of the presence of respiratory symptoms.

A molecular pathological study of four cases of ciliated muconodular papillary tumors of the lung.

Ciliated muconodular papillary tumors (CMPTs) are a recently categorized benign or low-grade malignant neoplasm that develops in the peripheral lung. Only about 40 cases have been reported to date, and the clinicopathological characteristics have yet to be defined in detail. Here, we present four cases of CMPTs with a focus on their immunohistochemical profiles and driver gene mutations. These tumors were a papillary proliferation of a mixture of ciliated, mucous, and basal cells located in the peripheral lung. Ciliated, mucous and basal cells were positive for TTF-1 when using the clone SPT24, but negative for HNF-4α. Basal cells were positive for p40. Mucous cells in some tumors were positive for MUC5AC and MUC6. The Ki-67 index was less than 5%, and strong expression of p53 was not detected. Three of the four tumors had a BRAF (V600E) driver mutation, an EGFR (del E746-T751/S752V) driver mutation, or driver mutations in both EGFR (E709G) and KRAS (G12V). These mutation types are rare for any histological type of lung cancer. The present results confirmed that CMPT is a neoplasm with immunohistochemical features and driver gene mutations that are distinct from those of common lung tumors.

Contralateral tension pneumothorax during video-assisted thorascoscopic surgery for lung cancer: a case report.

Contralateral tension pneumothorax during one-lung ventilation is a rare but catastrophic surgical complication. A 72-year-old Japanese male with lung cancer underwent right upper lobectomy with video-assisted thoracoscopic surgery. Despite use of various methods for maintaining oxygenation during one-lung ventilation, percutaneous oxygen saturation was unstable from the start of surgery and suddenly decreased with a drop in blood pressure. An intraoperative chest X-ray revealed a tension pneumothorax of the dependent lung. Insertion of a chest drain saved the patient's life. This case suggests that a contralateral tension pneumothorax should be considered as a possible cause when adequate oxygenation cannot be maintained during one-lung ventilation.

Update on the potential significance of psammoma bodies in lung adenocarcinoma from a modern perspective.

AIMS: Psammoma bodies are concentrically lamellated microscopic structures made of calcium. They are commonly observed in papillary carcinomas of the thyroid gland and serous papillary adenocarcinomas of the ovary, but are also occasionally detected in lung adenocarcinomas. Only one study, published in 1972, has systematically described the significance of psammoma bodies in lung adenocarcinomas. The aim of this study was to update the significance of psammoma bodies in lung adenocarcinomas from a modern perspective. METHODS AND RESULTS: Psammoma bodies were detected in 7.2% (59/822) of the adenocarcinomas examined, among which the papillary (20.3%, 12/59) and acinar (44.1%, 26/59) histological subtypes, with the feature of a terminal respiratory unit (91.5%, 54/59), were dominant. Malignant potential (cell growth activity measured by Ki67 labelling, lymph node metastasis, and postoperative survival) did not significantly differ between adenocarcinomas with and without psammoma bodies. On the basis of cytogenetic features, adenocarcinomas with psammoma bodies were preferentially affected by tyrosine kinase inhibitor (TKI)-targetable driver mutations [EGFR (69.8%, 37/53), ALK (13.2%, 7/53), and ROS1 (1.9%, 1/53)]. Multivariate analyses confirmed that psammoma bodies may constitute an independent predictor for these mutations, particularly EGFR and ALK mutations. CONCLUSIONS: Psammoma bodies may predict a favourable response of lung adenocarcinomas to TKIs.

Evaluation of a digital drainage system (Thopaz) in over 250 cases at a single site: A retrospective case-control study.

PURPOSE: The aim of this study was to evaluate the efficacy of the Thopaz system, a new drainage system in management of general thoracic surgery, based on a review of our clinical practice and a comparison of the utility of the Thopaz device compared with a standard drainage system. METHODS: A review of 540 thoracic surgeries at our hospital was performed. These cases were divided into 275 treated with the Thopaz system from April 2014 to March 2015 and 265 treated with a standard system from April 2013 to March 2014. The characteristics of patients and outcomes after surgery were compared in these 2 groups. RESULTS: The characteristics of the patients were similar in the 2 groups. Outcomes after surgery, including types of operation, period of chest tube placement, chest tube reinsertion rate and clamping test rate also did not differ significantly between the groups. CONCLUSIONS: The non-inferiority of the Thopaz system compared to a standard system was verified statistically. With advantages of providing objective data as a small portable system, in addition to the quietness of the unit and the ease of setup and operation, Thopaz system is likely to become mainstream in postoperative management in general thoracic surgery.

Isolated Brain Metastases as the First Relapse After the Curative Surgical Resection in Non-Small-Cell Lung Cancer Patients With an EGFR Mutation.

INTRODUCTION: The aim of this study was to clarify the incidence and disease behavior of brain metastases (BM) without extracranial disease (ie, isolated BM) as the first relapse after curative surgery in non-small-cell lung cancer (NSCLC) patients, analyzed according to epidermal growth factor receptor (EGFR) mutation status. PATIENTS AND METHODS: A review of the medical charts of consecutive NSCLC patients diagnosed between 2005 and 2016 with BM as the first relapse after curative surgery was performed. RESULTS: Among 1191 patients evaluated for EGFR mutation status, 28 patients who met the inclusion criteria were divided into 2 groups: EGFR mutation group (16 patients) and wild type group (12 patients). At BM diagnosis, the EGFR-mutation group tended to have more commonly isolated BM compared with that in the wild type group (11 of 16 vs. 3 of 12; P = .054). In the EGFR mutation group, the patients with isolated BM showed longer overall survival than those with non-isolated BM (39.6 vs. 18.7 months; P = .038). Notably, isolated BM in the EGFR mutation group was neurologically asymptomatic in 10 of the 11 patients. With regard to upfront treatment for isolated BM in the EGFR mutation group, 10 of 11 patients were treated with only cranial radiotherapy without EGFR tyrosine kinase inhibitors, but two-thirds of the patients (7 of 11; 64%) developed extracranial disease during the study period. CONCLUSION: In curatively resected NSCLC patients with EGFR mutation, isolated BM would be correlated with better prognosis, but regarded as a precursor to systemic disease. Because isolated BM can be neurologically asymptomatic, it would be important to periodically perform cranial evaluation to detect isolated BM.

Relationship between non-TRU lung adenocarcinomas and bronchiolar metaplasia - potential implication in their histogenesis.

Lung adenocarcinomas (ADCs) have been roughly divided into two groups: the terminal respiratory unit (TRU) type and non-TRU type. These ADCs appear to develop through exclusive carcinogenetic pathways because of differences in their cellular morphologies and the profiles of protein expression and genetic alterations. The TRU type develops from atypical adenomatous hyperplasia as a precursor. On the other hand, the histogenesis of the non-TRU type has not yet been defined in detail. We herein investigated histopathological changes in the non-tumor lung tissues of patients with non-TRU-type ADCs in order to define their potential histogenesis. The non-TRU type preferentially occurs in patients with interstitial pneumonia, in whom tumors are located in honeycomb lesions and are associated with bronchiolar metaplasia (BM). Among patients without interstitial pneumonia, non-tumor lung tissues from non-TRU-type ADCs were often affected by multiple BM. In these cases, tumors often were associated with BM. Metaplastic cells adjacent to non-TRU-type ADCs ectopically expressed HNF-4α, a marker for non-TRU-type ADCs. These results suggest that the non-TRU type develops through distinct histogenesis, in which BM is implicated.

The potential significance of alpha-enolase (ENO1) in lung adenocarcinomas - A utility of the immunohistochemical expression in pathologic diagnosis.

We herein analyzed the relationships among the immunohistochemical expression of alpha-enolase (ENO1) and clinicopathological factors in order to define the significance of ENO1 in lung adenocarcinomas (ADCs). ENO1 expression was detected in most of the ADCs examined (95.8%), but not in bronchial and alveolar epithelia. ENO1 expression was typically observed in the cytoplasm among most ADCs (95.8%), but was also detected in the nucleus (56.3%). The levels were significantly higher in terminal respiratory unit (TRU) cytological subtype ADCs. Neither cytoplasmic nor nuclear expression was associated with any other clinicopathological factors including post-operative survival and growth activity. These results suggest that ENO1 is a crucial factor promoting neoplastic transformation exclusively in TRU subtype ADCs. We also investigated the potential utility of the immunohistochemical expression of ENO1 to differentiate TRU-type ADC cells from the reactive hyperplasia of pneumocytes and bronchiolar epithelial cells because difficulties are associated with discriminating these lesions in small biopsy specimens. The sensitivity and specificity of ENO1 (cytoplasmic/nuclear) were 87.5%/37.5% and 88.9%/100%, respectively, which are superior to those of p53 (18.8% and 100%). ENO1 has potential as a biomarker to assist in the histopathological detection of TRU subtype ADC cells.

The pathological features of idiopathic interstitial pneumonia-associated pulmonary adenocarcinomas.

AIMS: To investigate the pathological features of idiopathic interstitial pneumonia (IIP)-associated pulmonary adenocarcinoma. METHODS AND RESULTS: Surgically resected adenocarcinomas associated with IIP (the IIP group) and adenocarcinomas without IIP (the non-IIP group) were subjected to analysis. Adenocarcinomas in the IIP group were subdivided into two groups: one group included tumours connected to bronchiolar metaplasia in honeycomb lesions (the H-IIP group), and the other included tumours unrelated to honeycomb lesions (the NH-IIP group). Histomorphological appearance and immunohistochemical expression were compared among the H-IIP group, the NH-IIP group, and the non-IIP group. Most of the tumour cells in the H-IIP group had a tall, columnar shape that showed similar features to proximal bronchial epithelium, whereas tumour cells in the NH-IIP group and the non-IIP group had a club-like shape that showed similar features to respiratory bronchiolar/alveolar epithelium. Adenocarcinomas in the H-IIP group tended to be negative for thyroid transcription factor-1 (TTF-1) and positive for hepatocyte nuclear factor-4α (HNF-4α). The frequency of EGFR mutations was significantly lower in adenocarcinomas in the H-IIP group, although the frequencies of KRAS and ALK mutations did not differ among the three groups. CONCLUSIONS: Idiopathic interstitial pneumonia-associated pulmonary adenocarcinomas, especially those arising from honeycomb lesions, have distinct pathological features.

Two surgical cases of thymic MALT lymphoma associated with multiple lung cysts: possible association with Sjögren's syndrome.

Thymic mucosa-associated lymphoid tissue (MALT) lymphoma is rare. Sjögren's syndrome (SjS) has strong association with thymic MALT lymphoma but the exact etiology is unknown. On the other hand, SjS is characterized by the complication of various lung manifestations, including lung cysts. The mechanism for these lesions is also unknown. But the underlying SjS could result in MALT lymphoma with lung cysts. Herein, we demonstrate two surgical cases of thymic MALT lymphoma associated with multiple lung cysts and the characterization of this rare tumor. During surgery, the tumors were found to be well capsuled and had no adhesion or invasion to the surrounding tissues consistent with its characteristics of low grade malignancy. When thymic MALT lymphoma is suspected clinically, video-assisted thoracoscopic surgery might be the best approach for diagnosis. We propose that radiological findings of a thymic tumor along with lung cysts are an indication of thymic MALT lymphoma.