Detailed clinical course of a patient with rapidly progressing sarcomatoid pleural mesothelioma without p16 deletion with systemic haematogenous metastasis to soft tissues.

Sarcomatoid mesothelioma is difficult to differentiate from other mesotheliomas. Here, we describe the case of a man in his early 80s with sarcomatoid mesothelioma and a history of asbestos exposure. He initially presented with right-sided chest pain and was examined. Right-sided pleural effusion was detected; therefore, he was hospitalised. Based on the observed pleural effusion and biopsy result, the presence of a malignant tumour was excluded; hence, he was diagnosed with benign asbestos pleurisy. He subsequently developed left-sided pleural effusion, masses and lung nodules, and died 9.5 months after the initial examination. A definitive diagnosis of sarcomatoid mesothelioma with rapid systemic progression was established after detailed investigations using autopsy specimens. This rare case of mesothelioma-without p16 deletion (detected using fluorescence in situ hybridisation)-presented differently from the usual sarcomatoid mesothelioma.

Respiratory disease in workers handling cross-linked water-soluble acrylic acid polymer.

Eight workers involved in packing cross-linked water-soluble acrylic acid polymer, an organic substance, developed pulmonary fibrosis, and the upper lobe was the most affected. The dust concentration in the polymer packing workstation was measured. Chest computed tomography (CT) was obtained for 82 individuals, including the 8 workers mentioned above. Three workers were histopathologically examined. In six of these eight workers, central pulmonary fibrosis and secondary bulla formation caused pneumothorax. Histopathologically, multiple centrilobular fibrotic foci were observed. Chest CT revealed centrilobular nodular opacity and interlobular septal thickening, suggesting early lesions in the workers because the dust concentration was remarkably high. Although the pathogenesis of the disease is unclear, we reported the occurrence of pulmonary fibrosis caused by the exposure to cross-linked water-soluble acrylic acid polymers in humans as it has not been reported earlier.

Programmed Death-Ligand 1-Positive Squamous Cell Carcinoma Spontaneously Regressed after Percutaneous Needle Biopsy.

Spontaneous lung cancer regression is a very rare course of disease. A 60-year-old male patient was admitted to our hospital with pneumonia and a 19 mm-sized nodule shadow in the S4 of the left lung on chest computed tomography (CT). A percutaneous needle biopsy was performed, and a diagnosis of programmed death-ligand 1-positive squamous cell lung carcinoma was made based on pathological findings. The patient was followed up with imaging because the lesion has reduced in size on chest CT. We report the possibility that cellular immune mechanisms triggered by needle biopsy contributed to spontaneous regression.

Mechanisms of pulmonary disease in F344 rats after workplace-relevant inhalation exposure to cross-linked water-soluble acrylic acid polymers.

BACKGROUND: Recently in Japan, six workers at a chemical plant that manufactures resins developed interstitial lung diseases after being involved in loading and packing cross-linked water-soluble acrylic acid polymers (CWAAPs). The present study focused on assessing lung damage in rats caused by workplace-relevant inhalation exposure to CWAAP and investigated the molecular and cellular mechanisms involved in lung lesion development. METHODS: Using a whole-body inhalation exposure system, male F344 rats were exposed once to 40 or 100 mg/m3 of CWAAP-A for 4 h or to 15 or 40 mg/m3 of CWAAP-A for 4 h per day once per week for 2 months (9 exposures). In a separate set of experiments, male F344 rats were administered 1 mg/kg CWAAP-A or CWAAP-B by intratracheal instillation once every 2 weeks for 2 months (5 doses). Lung tissues, mediastinal lymph nodes, and bronchoalveolar lavage fluid were collected and subjected to biological and histopathological analyses. RESULTS: A single 4-h exposure to CWAAP-A caused alveolar injury, and repeated exposures resulted in regenerative changes in the alveolar epithelium with activation of TGFß signaling. During the recovery period after the last exposure, some alveolar lesions were partially healed, but other lesions developed into alveolitis with fibrous thickening of the alveolar septum. Rats administered CWAAP-A by intratracheal instillation developed qualitatively similar pulmonary pathology as rats exposed to CWAAP-A by inhalation. At 2 weeks after intratracheal instillation, rats administered CWAAP-B appeared to have a slightly higher degree of lung lesions compared to rats administered CWAAP-A, however, there was no difference in pulmonary lesions in the CWAAP-A and CWAAP-B exposed rats examined 18 weeks after administration of these materials. CONCLUSIONS: The present study reports our findings on the cellular and molecular mechanisms of pulmonary disease in rats after workplace-relevant inhalation exposure to CWAAP-A. This study also demonstrates that the lung pathogenesis of rats exposed to CWAAP-A by systemic inhalation was qualitatively similar to that of rats administered CWAAP-A by intratracheal instillation.

Dose-response relationship of pulmonary disorders by inhalation exposure to cross-linked water-soluble acrylic acid polymers in F344 rats.

BACKGROUND: In Japan, six workers handling cross-linked water-soluble acrylic acid polymer (CWAAP) at a chemical plant suffered from lung diseases, including fibrosis, interstitial pneumonia, emphysema, and pneumothorax. We recently demonstrated that inhalation of CWAAP-A, one type of CWAAP, causes pulmonary disorders in rats. It is important to investigate dose-response relationships and recoverability from exposure to CWAAPs for establishing occupational health guidelines, such as setting threshold limit value for CWAAPs in the workplace. METHODS: Male and female F344 rats were exposed to 0.3, 1, 3, or 10 mg/m3 CWAAP-A for 6 h/day, 5 days/week for 13 weeks using a whole-body inhalation exposure system. At 1 h, 4 weeks, and 13 weeks after the last exposure the rats were euthanized and blood, bronchoalveolar lavage fluid, and all tissues including lungs and mediastinal lymph nodes were collected and subjected to biological and histopathological analyses. In a second experiment, male rats were pre-treated with clodronate liposome or polymorphonuclear leukocyte-neutralizing antibody to deplete macrophages or neutrophils, respectively, and exposed to CWAAP-A for 6 h/day for 2 days. RESULTS: CWAAP-A exposure damaged only the alveoli. The lowest observed adverse effect concentration (LOAEC) was 1 mg/m3 and the no observed adverse effect concentration (NOAEC) was 0.3 mg/m3. Rats of both sexes were able to recover from the tissue damage caused by 13 weeks exposure to 1 mg/m3 CWAAP-A. In contrast, tissue damage caused by exposure to 3 and 10 mg/m3 was irreversible due to the development of interstitial lung lesions. There was a gender difference in the recovery from CWAAP-A induced pulmonary disorders, with females recovering less than males. Finally, acute lung effects caused by CWAAP-A were significantly reduced by depletion of alveolar macrophages. CONCLUSIONS: Pulmonary damage caused by inhalation exposure to CWAAP-A was dose-dependent, specific to the lung and lymph nodes, and acute lung damage was ameliorated by depleting macrophages in the lungs. CWAAP-A had both a LOAEC and a NOAEC, and tissue damage caused by exposure to 1 mg/m3 CWAAP-A was reversible: recovery in female rats was less than for males. These findings indicate that concentration limits for CWAAPs in the workplace can be determined.

A patient with epithelioid pleural mesothelioma (Myxoid variant) who survived for a long period without treatment.

Pleural mesothelioma is a disease with a very poor prognosis. Here, we report a mesothelioma patient who survived for 5 years and a half. As a result of the autopsy, the tumor was diagnosed as a myxoid variant, which is internationally proposed as a histological subtype of epithelioid mesothelioma with a relatively favorable prognosis. Since patients with this disease are expected to survive for a long period even without treatment, careful determination of the therapeutic approach is considered necessary. This report is considered to be the first of a myxoid variant epithelioid pleural mesothelioma in Japan.

Recurrent gastric volvulus associated with a gastrointestinal stromal tumor: A case report.

INTRODUCTION: Gastric volvulus (GV) is defined as a rotation of the stomach along its short or long axis leading to variable degrees of gastric outlet obstruction. Rotation of the stomach >180° may cause closed loop obstruction and possible strangulation, which often causes acute abdominal pain. Strangulation and gangrene of the twisted stomach sometimes occurs, which demands immediate surgical intervention. We report a case of acute gastric volvulus due to a gastrointestinal stromal tumor (GIST), with multiple recurrences, that eventually required emergency gastrectomy. PRESENTATION OF THE CASE: A 71-year-old woman with a history of recurrent epigastric pain, nausea, and anorexia was diagnosed to have a 70-mm sized submucosal tumor (SMT) in the lesser curvature of the stomach. An elective gastrectomy was planned; however, before the procedure, she visited the emergency room with acute recurrent epigastric pain associated with postural variations. Computed tomography (CT) revealed a GV and the tumor had shifted to the greater curvature. An emergency gastrectomy was performed. The postoperative course was uneventful and pathological examination revealed features consistent with that of GIST. DISCUSSION: GV with GIST has rarely been reported and risk factors such as size or localization are unknown. In this case, GV was probably caused by GIST of the stomach, which was large and heavy enough to rotate the gastric body around the mesenteroaxis. CONCLUSION: Surgical intervention without delay should be planned in similar scenarios accounting for the risk of GV in GIST.

Asbestosis and other pulmonary fibrosis in asbestos-exposed workers: high-resolution CT features with pathological correlations.

OBJECTIVE: The purpose was to identify distinguishing CT features of pathologically diagnosed asbestosis, and correlate diagnostic confidence with asbestos body burden. METHODS: Thirty-three workers (mean age at CT: 73 years) with clinical diagnoses of asbestosis, who were autopsied (n = 30) or underwent lobectomy (n = 3), were collected. Two radiologists independently scored high-resolution CT images for various CT findings and the likelihood of asbestosis was scored. Two pathologists reviewed the pathology specimens and scored the confidence of their diagnoses. Asbestos body count was correlated with CT and pathology scores. RESULTS: Pathologically, 15 cases were diagnosed as asbestosis and 18 cases with various lung fibroses other than asbestosis. On CT, only the score of the subpleural curvilinear lines was significantly higher in asbestosis (p = 0.03). Accuracy of CT diagnosis of asbestosis with a high confidence ranged from 0.73 to 0.79. Asbestos body count positively correlated with CT likelihood of asbestosis (r = 0.503, p = 0.003), and with the confidence level of pathological diagnosis (r = 0.637, p < 0.001). CONCLUSIONS: Subpleural curvilinear lines were the only clue for the diagnosis of asbestosis. However, this was complicated by other lung fibrosis, especially at low asbestos body burden. KEY POINTS: • Various patterns of pulmonary fibrosis occurred in asbestos-exposed workers. • The fibre burden in lungs paralleled confident CT diagnosis of asbestosis. • The fibre burden in lungs paralleled confident pathological diagnosis of asbestosis. • Subpleural curvilinear lines were an important CT finding favouring asbestosis.

Significant relationship between the extent of pleural plaques and pulmonary asbestos body concentration in lung cancer patients with occupational asbestos exposure.

BACKGROUND: The aim of this study was to elucidate whether there is a relationship between the extent of pleural plaques and pulmonary asbestos body concentration (PABC). METHODS: The subjects were 207 lung cancer patients with occupational asbestos exposure. We determined the plaque extent by findings on chest images using our own criteria. PABCs were measured in resected or autopsy lung specimens. RESULTS: There was a significant relationship between plaque extent and PABC. Seventy-five percent of the patients determined to have extensive plaques based on our criteria had a PABC of ≥5,000 asbestos bodies per gram of dry lung tissue, which is one of the certification criteria of lung cancer caused by asbestos for workers' compensation in Japan. CONCLUSIONS: In lung cancer patients, the plaque extent had a significant positive relationship with the PABC. The plaque extent would be useful as a proxy for PABC for lung cancer compensation purposes.

[Occupational lung diseases other than asbestos- and indium-related disease].

In our country, pneumoconiosis used to hold an overwhelmingly majority in respiratory occupational lung diseases. Although the number of pneumoconiosis cases has been decreasing certainly, new cases have been arising even today. In addition, in place of pneumoconiosis or asbestos-related diseases, occupational asthma has become the most common forms of occupational lung disease in many industrialized countries. Occupational asthma has been implicated in 9 to 15% of adult asthma in the United States. Although the environmental causes of occupational lung disease are clear, the mechanisms of the diseases are not fully understood and need to be further elucidated.

Optimal predictive value of preoperative serum carcinoembryonic antigen for surgical outcomes in stage I non-small cell lung cancer: differences according to histology and smoking status.

BACKGROUND: The cutoff value of preoperative serum carcinoembryonic antigen (CEA) levels has not been investigated using appropriate subgroup analyses for non-small cell lung carcinoma (NSCLC). This study was undertaken to determine whether the most predictive preoperative CEA level for risk of recurrence differs according to histological type, and how smoking status influences predictive values in Stage I NSCLC. METHODS: Subjects comprised Stage I NSCLC patients [141 patients with adenocarcinoma (ADC) and 36 with squamous cell carcinoma (SCC)]. RESULTS: In patients with Stage I ADC, recurrence-free survival (RFS) differed most significantly at a preoperative CEA level of 2.5 ng/ml, regardless of smoking status. Cases with preoperative CEA >2.5 ng/ml correlated with male sex, high maximum standard uptake value on (18) F-fluorodeoxyglucose positron emission tomography, poorer histopathological grade, lymphatic invasion, and smoking status. Importantly, preoperative CEA >2.5 ng/ml was identified as an independent risk factor for recurrence (P = 0.0015). Conversely, in patients with SCC, a preoperative CEA level of 3.0 ng/ml was the most predictive threshold. CONCLUSIONS: Thresholds of preoperative CEA should be considered when predicting risk of relapse, even if these levels are within normal limits, as optimal cutoff levels may vary according to histological type.

Angiolymphatic invasion exerts a strong impact on surgical outcomes for stage I lung adenocarcinoma, but not non-adenocarcinoma.

Angiolymphatic invasion (ALI), representing lymphatic invasion (Ly) and intratumoral vascular invasion (V), is considered to be a useful prognostic factor for pathological stage I non-small cell lung carcinoma (NSCLC). However, the types of tumor for which prognoses are most influenced by ALI positivity have not previously been discussed, nor has the question of whether these findings should influence postoperative therapeutic decision-making after complete resection. The present study investigated 195 cases of stage I NSCLC treated by potentially curative surgical resection of the primary tumor and systematic lymphadenectomy. ALI-positive (ALI(+)) results were found in 31.8% of tumors, and 5.1% exhibited both Ly(+) and V(+). Five-year recurrence-free survival was significantly lower in ALI(+) cases (50.6%) than in ALI(-) cases (85.9%; p<0.0001, log-rank test). In particular, 5-year recurrence-free survival rate was only 10.0% for Ly(+)V(+) cases. ALI(+) correlated with high age, male sex, tumor size (>2.0 cm), elevated preoperative serum carcinoembryonic antigen level (≥5.0 ng/mL), high maximum standard uptake value (SUVmax) on (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) (≥5.0), pleural invasion, and histological classification of non-adenocarcinoma (ADC). According to histopathological subset analyses, ALI(+) was associated with shorter recurrence-free survival than ALI(-) only among ADC patients (p<0.0001, log-rank test), and not among non-ADC patients (p=0.7710). High preoperative serum CEA level, high SUVmax on FDG-PET, pleural invasion, Ly(+), and V(+) were significant risk factors for recurrence in univariate Cox survival analysis among stage I ADC patients. Importantly, Ly(+) and V(+) were identified as independent risk factors for recurrence by multivariate analysis. Histopathological detection of ALI as a risk factor for recurrence should be considered for inclusion in the staging criteria and as additional information for determining postoperative adjuvant treatment of stage I NSCLC, particularly among ADC patients, but not among non-ADC patients.

Spontaneous pneumothorax in a patient with dendriform pulmonary ossification: report of a case.

We report herein the rare case of a patient with dendriform pulmonary ossification (DPO) who developed spontaneous pneumothorax. A 33-year-old male with a history of bronchial asthma presented with pneumothorax of the left lung. An intraoperative inspection revealed no findings of bullae in the entire left lung, but inflammatory pleural changes were identified on the interlobular surface of the left lower lobe. In addition, hard, twig-like configurations were clearly palpable in the subpleural parenchyma and were resected. A histological examination showed acicular bone formations containing myeloid tissue and marrow fat in the lung. DPO was thus diagnosed, and the bony spines were considered to have caused a rupture of the elastic fiber layer of the visceral pleura. DPO may thus have been directly responsible for the pneumothorax in this case.

[An autopsy case of asbestos-related pleomorphic carcinoma of the lung].

A 50-year-old man with a history of asbestos inhalation developed symptoms related to a metastatic brain tumor was admitted. Chest X-ray images showed an opacity in the left lower lung field. We were unable to differentiate between lung cancer and malignant pleural tumor using either transbronchial lung biopsy or computed tomography (CT)-guided needle biopsy. After 3 months the patient died from rapid disease progression despite radiation therapy, drainage of large quantities of the pleural effusion and chemotherapy. A diagnosis of asbestos-related pleomorphic carcinoma of the lung was made after autopsy and immunohistochemical examination of the tumor.

Progression of pneumoconiosis in coal miners after cessation of dust exposure: a longitudinal study based on periodic chest X-ray examinations in Hokkaido, Japan.

BACKGROUND: The progression rate of pneumoconiosis in retired coal miners over ten years has not been studied in Japan. METHODS: A retrospective longitudinal study was undertaken using chest X-rays of 1091 pneumoconiosis subjects in Hokkaido, Japan between 1985 and 2005. RESULTS: The final numbers of subjects were 207 (19% of the entry) after 1 decade and 85 (8%) after 2 decades. Sixty-two percent of 207 subjects after 1 decade and 29% of 85 showed progression in 2 decades. Thirty-one percent of ILO category 1 and 55% of category 2 subjects showed progression to complicated pneumoconiosis after 1 decade, and 6% (4 of 64) of category 1 and 6% (5 of 77) of category 2 subjects progressed to complicated pneumoconiosis during 2 decades. CONCLUSION: The progression of pneumoconiosis was observed after the cessation of dust exposure, especially during the first 10 years.

Primary peripheral adenoid cystic carcinoma of the lung and literature comparison of features.

Adenoid cystic carcinoma arising from the peripheral lung is rare. Here, we describe adenoid cystic carcinoma that developed in the peripherally in S(9) of the right lower lobe of an 84-year-old woman. Cell blocks prepared from the bronchial wash specimens exhibited the cribriform formation. An immunohistochemical examination of the surgically resected tumor revealed positive thyroid transcription factor-1 and c-kit staining. Exons 9 and 11 of c-kit in tumor cells were not mutated. We compared the clinical features of this patient with those of 10 others described in the English-language literature.