Total Synthesis of Keramaphidin B and Ingenamine by Base-Catalyzed Diels-Alder Reaction Using Dynamic Regioselective Crystallization.

The control of the selectivity is a central issue in the total synthesis of complex natural products. In this paper, we report the total synthesis of (±)-keramaphidin B and (±)-ingenamine. The key reaction is a DMAP-catalyzed Diels-Alder reaction in which the regioselectivity is completely controlled by dynamic crystallization. Our synthesis successfully demonstrates that dynamic crystallization can be an alternative when the selectivity is not controlled by either kinetic or thermodynamic approaches in solution.

Impact of obesity in asthma: Possible future therapies.

Obesity is one of the factors associated with the severity of asthma. Obesity is associated with aggravation of the pathophysiology of asthma, including exacerbations, airway inflammation, decreased pulmonary function, and airway hyperresponsiveness. The present review addresses the characteristics of asthma with obesity, focusing especially on the heterogeneity caused by the degree of type 2 inflammation, sex differences, the onset of asthma, and race differences. To understand the severity mechanisms in asthma and obesity, such as corticosteroid resistance, fatty acids, gut microbiome, and cytokines, several basic research studies are evaluated. Finally, possible future therapies, including weight reduction, microbiome-targeted therapies, and other molecular targeted therapies are addressed. We believe that the present review will contribute to better understanding of the severity mechanisms and the establishment of novel treatments for severe asthma patients with obesity.

Thymic stromal lymphopoietin contributes to ozone-induced exacerbations of eosinophilic airway inflammation via granulocyte colony-stimulating factor in mice.

BACKGROUND: Ozone is one of the triggers of asthma, but its impact on the pathophysiology of asthma, such as via airway inflammation and airway hyperresponsiveness (AHR), is not fully understood. Thymic stromal lymphopoietin (TSLP) is increasingly seen as a crucial molecule associated with asthma severity, such as corticosteroid resistance. METHODS: Female BALB/c mice sensitized and challenged with house dust mite (HDM) were exposed to ozone at 2 ppm for 3 h. Airway inflammation was assessed by the presence of inflammatory cells in bronchoalveolar lavage fluid and concentrations of cytokines including TSLP in lung. Anti-TSLP antibody was administered to mice to block the signal. Survival and adhesion of bone marrow-derived eosinophils in response to granulocyte colony-stimulating factor (G-CSF) were evaluated. RESULTS: Ozone exposure increased eosinophilic airway inflammation and AHR in mice sensitized and challenged with HDM. In addition, TSLP, but not IL-33 and IL-25, was increased in lung by ozone exposure. To confirm whether TSLP signaling is associated with airway responses to ozone, an anti-TSLP antibody was administered, and it significantly attenuated eosinophilic airway inflammation, but not AHR. Interestingly, G-CSF, but not type 2 cytokines such as IL-4, IL-5, and IL-13, was regulated by TSLP signaling associated with eosinophilic airway inflammation, and G-CSF prolonged survival and activated eosinophil adhesion. CONCLUSIONS: The present data show that TSLP contributes to ozone-induced exacerbations of eosinophilic airway inflammation and provide greater understanding of ozone-induced severity mechanisms in the pathophysiology of asthma related to TSLP and G-CSF.

Effect of Azithromycin on Exacerbations in Asthma Patients with Obesity: Protocol for a Multi-Center, Prospective, Single-Arm Intervention Study.

INTRODUCTION: Obesity is associated with severe asthma, but no specific treatment has been established. The gut microbiome is increasingly recognized as a crucial factor, but specific treatments focused on the gut microbiome have not been established. Recently, azithromycin has been found to have the capacity to attenuate exacerbations, a characteristic of severe asthma. The effect of azithromycin on obesity-induced severe asthma is not understood. METHODS: The purpose of the present study is to clarify the effect of azithromycin on exacerbations in asthmatic patients with obesity. To explore the mechanism, the gut microbiome, metabolites of microbes such as short-chain fatty acids, and blood inflammatory cytokines will be analyzed to evaluate the correlation with the effect of azithromycin on exacerbations in obesity-induced severe asthma. A multi-center, prospective, single-arm intervention study is planned. DISCUSSION: The present study will allow us to evaluate the effect of azithromycin on exacerbations, particularly in asthma patients with obesity, and explore biomarkers, targeting molecules including the gut microbiome, which are correlated with decreased exacerbations. The present results could contribute to identifying new therapeutic prospects and targeted microbes or molecules associated with severe clinical characteristics in asthmatic patients with obesity. TRIAL REGISTRATION: This study has been registered as a prospective study with the University Hospital Medical Information Network (UMIN0000484389) and the Japan Registry of Clinical Trials (jRCTs071220023).

Anti-cancer effect of afatinib, dual inhibitor of HER2 and EGFR, on novel mutation HER2 E401G in models of patient-derived cancer.

BACKGROUND: Precision medicine with gene panel testing based on next-generation sequencing for patients with cancer is being used increasingly in clinical practice. HER2, which encodes the human epidermal growth factor receptor 2 (HER2), is a potentially important driver gene. However, therapeutic strategies aimed at mutations in the HER2 extracellular domain have not been clarified. We therefore investigated the effect of EGFR co-targeted therapy with HER2 on patient-derived cancer models with the HER2 extracellular domain mutation E401G, based on our previous findings that this mutation has an epidermal growth factor receptor (EGFR)-mediated activation mechanism. METHODS: We generated a xenograft (PDX) and a cancer tissue-originated spheroid (CTOS) from a patient's cancer containing an amplified HER2 E401G mutation. With these platforms, we compared the efficacy of afatinib, a tyrosine kinase inhibitor having anti-HER2 and anti-EGFR activity, with two other therapeutic options: lapatinib, which has similar properties but weaker EGFR inhibition, and trastuzumab plus pertuzumab, for which evidence exists of treatment efficacy against cancers with wild-type HER2 amplification. Similar experiments were also performed with H2170, a cell line with wild-type HER2 amplification, to contrast the characteristics of these drug's efficacies against HER2 E401G. RESULTS: We confirmed that PDX and CTOS retained morphological and immunohistochemical characteristics and HER2 gene profiles of the original tumor. In both PDX and CTOS, afatinib reduced tumor size more than lapatinib or trastuzumab plus pertuzumab. In addition, afatinib treatment resulted in a statistically significant reduction in HER2 copy number at the end of treatment. On the other hand, in H2170 xenografts with wild-type HER2 amplification, trastuzumab plus pertuzumab was most effective. CONCLUSIONS: Afatinib, a dual inhibitor of HER2 and EGFR, showed a promising effect on cancers with amplified HER2 E401G, which have an EGFR-mediated activation mechanism. Analysis of the activation mechanisms of mutations and development of therapeutic strategies based on those mechanisms are critical in precision medicine for cancer patients.

Factors related to the diagnosis of lung cancer by transbronchial biopsy with endobronchial ultrasonography and a guide sheath.

BACKGROUND: Transbronchial biopsy (TBB) with endobronchial ultrasonography and a guide sheath (EBUS-GS) is an effective examination tool for the diagnosis of lung cancer. Factors related to making the diagnosis are still not fully understood. METHODS: A total of 367 patients who underwent EBUS-GS and were diagnosed with lung cancer in Saga University Hospital were investigated retrospectively. Clinical characteristics were compared between 244 patients who were diagnosed with lung cancer and 123 patients who were not diagnosed by TBB with EBUS-GS but were diagnosed by other examinations. RESULTS: Size of target lesion, rate of patients with target lesion size ≥20 mm, presence of the bronchus sign, and detection by EBUS imaging were significantly associated with making the diagnosis (all p < 0.01). In patients whose lesion was detected by EBUS imaging, patients with positive findings within the lesion were significantly more often diagnosed by TBB with EBUS-GS than those with positive findings adjacent to the lesion (p < 0.01). The odds ratio (OR) of patients whose lesion was detected by EBUS imaging (OR [95% confidence interval] 14.5 [8.0-26.4]) tended to be higher compared to the ORs of size of lesion ≥20 mm (3.9 [2.2-6.8]) and the bronchus sign (7.5 [4.6-12.2]). CONCLUSION: Targeted lesion diameter ≥20 mm, bronchus sign, and detection by EBUS imaging, especially within the lesion, are important factors for the diagnosis of lung cancer by TBB with EBUS-GS.

Obesity affects pulmonary function in Japanese adult patients with asthma, but not those without asthma.

Obesity is associated with the severity of asthma, which is characterized by airway obstruction. Pulmonary function testing is one of the important examinations for evaluating airway obstruction. However, the impact of obesity on pulmonary function in patients with asthma is not fully understood. A total of 193 patients with asthma and 2159 patients without asthma who visited Saga University Hospital were investigated retrospectively. Obesity was defined as a body mass index (BMI) greater than 25 kg/m2. Pulmonary functions including forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were compared between patients with and without asthma, focusing especially on obesity. FVC percent predicted and FEV1 percent predicted were significantly lower in patients with asthma than in those without asthma (p = 0.03, < 0.01 respectively). In patients with asthma, FVC percent predicted and FEV1 percent predicted were significantly lower in patients with obesity than in those without obesity (all p < 0.01). In addition, BMI was negatively correlated with FEV1 (r =- 0.21, p = 0.003) and FVC (r = - 0.15, p = 0.04), along with the percent predicted. On multivariate analysis in patients with asthma, FVC (ß [95% confidence interval] 0.12 [0.02-0.22], p = 0.02) and FEV1 (0.13 [0.05-0.22], p < 0.01) were still significantly different between patients with and without obesity. However, these obesity-associated differences were not observed in patients without asthma. Obesity reduces pulmonary function, including FVC and FEV1, in patients with asthma, but not in those without asthma.

Anti-IL-5 Agents for the Treatment of Idiopathic Chronic Eosinophilic Pneumonia: A Case Series.

PURPOSE: Idiopathic chronic eosinophilic pneumonia (ICEP) is a rare, chronic respiratory disease. Corticosteroid therapy is effective for ICEP, but relapse is frequent after its tapering, which leads to chronic use and corticosteroid-related adverse effects. Currently, biological agents targeting interleukin 5 (IL-5) are considered alternatives for treating ICEP patients with frequent relapse, but the detailed effects are not fully understood. PATIENTS AND METHODS: The clinical characteristics of 30 patients with ICEP, especially 12 patients with ICEP who experienced relapse after corticosteroid dose tapering, were evaluated retrospectively. In addition, 4 ICEP patients with frequent relapse treated by IL-5-targeted biological agents were reviewed. RESULTS: Of the 30 patients diagnosed with ICEP, 12 patients (40.0%) recurred after corticosteroid dose tapering, and 9 (30.0%) were treated with maintenance doses of corticosteroid. Of ICEP patients who experienced recurrence, 6 (50.0%) had frequent relapses (2 or more times). All 4 patients treated with anti-IL-5 agents had their corticosteroid dose reduced without any relapses; in 3 patients, corticosteroids were withdrawn. CONCLUSION: Anti-IL-5 agents might be alternatives for treating ICEP patients with frequent relapses.

Factors Associated with Reduction of Sedentary Time Following Tiotropium/Olodaterol Therapy in Treatment-Naïve Chronic Obstructive Pulmonary Disease.

BACKGROUND: Prolonged sedentary behavior is associated with worse prognosis in patients with chronic obstructive pulmonary disease (COPD). Our previous study found that first-line dual therapy with tiotropium/olodaterol significantly reduces sedentary time compared to tiotropium monotherapy in Japanese patients with treatment-naïve COPD, although the characteristics of responders to dual-therapy versus monotherapy for COPD are still unclear. METHODS: Patients with treatment-naïve COPD were randomized to receive either tiotropium or tiotropium/olodaterol treatment for 12 weeks. Physical activity was assessed using a triaxle accelerometer for 2 weeks before and after treatment. This analysis focused on the change in sedentary time, indicated by physical activity of 1.0-1.5 metabolic equivalents (METs), with stratification for the following factors: age, body mass index (BMI), pulmonary function, COPD assessment test (CAT), the 6-minute walk distance (6MWD), and physical activity level at study entry. RESULTS: Thirty-five patients received tiotropium/olodaterol and 34 patients received tiotropium. In patients with lower inspiratory capacity at study entry, a significant reduction in sedentary time was observed in the tiotropium/olodaterol group compared with the tiotropium group (Tio: -12.8 ± 13.5 min, Tio/Olo: -65.1 ± 21.0 min, mean difference, -52.2 min, 95% CI -103.6 to 0.88, p = 0.046). In patients with a shorter duration of physical activity of ≥2 METs at study entry, a significant reduction of sedentary time was observed in the tiotropium/olodaterol group compared with the tiotropium group (Tio: -3.3 ± 17.5 min, Tio/Olo: -72.9 ± 23.1 min, mean difference, -69.7 min, 95% CI -128.7 to -10.6, p = 0.02). There were no differences in terms of age, BMI, CAT score, 6MWD, FEV1, FVC, VC, and physical activity of 1.0-1.5 METs and ≥3.0 METs. CONCLUSION: This study showed that COPD patients with lower inspiratory capacity or shorter active time of ≥2.0 METs at study entry are likely to exhibit significantly greater reduction in sedentary time with tiotropium/olodaterol treatment.

Skeletal muscle is associated with exercise tolerance evaluated by cardiopulmonary exercise testing in Japanese patients with chronic obstructive pulmonary disease.

Decreasing exercise tolerance is one of the key features related to a poor prognosis in patients with chronic obstructive pulmonary disease (COPD). Cardiopulmonary exercise testing (CPET) is useful for evaluating exercise tolerance. The present study was performed to clarify the correlation between exercise tolerance and clinical parameters, focusing especially on the cross-sectional area (CSA) of skeletal muscle. The present study investigated 69 patients with COPD who underwent CPET. The correlations between oxygen uptake ([Formula: see text]) at peak exercise and clinical parameters of COPD, including skeletal muscle area measured using single-section axial computed tomography (CT), were evaluated. The COPD assessment test score (ρ = - 0.35, p = 0.02) was weakly correlated with [Formula: see text] at peak exercise. In addition, forced expiratory volume in one second (FEV1) (ρ = 0.39, p = 0.0009), FEV1/forced vital capacity (ρ = 0.33, p = 0.006), and the CSA of the pectoralis muscles (PMs) (ρ = 0.36, p = 0.007) and erector spinae muscles (ECMs) (ρ = 0.39, p = 0.003) were correlated with [Formula: see text] at peak exercise. Multivariate analysis adjusted by age and FEV1 indicated that PMCSA was weakly correlated after adjustment (ß value [95% confidence interval] 0.175 [0.03-0.319], p = 0.02). In addition, ECMCSA tended to be correlated, but not significantly after adjustment (0.192 [- 0.001-0.385] p = 0.052). The COPD assessment test, FEV1, FEV1/FVC, PMCSA, and ECMCSA were significantly correlated with [Formula: see text] at peak exercise.

Idiopathic eosinophilic pleurisy: A practical diagnostic approach.

A 37-year-old man with fever, cough, and dyspnea with no medical history developed an eosinophilic pleural effusion and blood eosinophilia. No evidence of malignancy or pathogens was detected in the pleural effusion, and the pleural specimen obtained by thoracoscopy showed eosinophilic infiltration with inflammatory granulation tissue without fibrinoid necrosis or malignant cells. Since a myeloproliferative disorder was also excluded, the diagnosis was idiopathic eosinophilic pleurisy. Corticosteroid treatment was started and then slowly tapered, and the eosinophilic pleural effusion resolved. Considering the various etiologies of eosinophilic pleurisy, a practical clinical approach to the investigation and diagnosis of eosinophilic pleurisy is presented.

A Low Body Mass Index Is Associated with Unsuccessful Treatment in Patients with Mycobacterium avium Complex Pulmonary Disease.

BACKGROUND: A low body mass index (BMI) has been reported to be a poor prognostic factor for Mycobacterium avium complex pulmonary disease (MAC-PD). The purpose of this study was to clarify the clinical features of MAC-PD in cases with a low BMI. METHODS: This retrospective study analyzed the data of patients diagnosed with MAC-PD at Saga University Hospital between 2008 and 2019. The analyzed patient characteristics included age, gender, BMI, symptoms, laboratory data, chest computed tomography findings, and the treatment courses. We also investigated the factors associated with successful treatment. RESULTS: In total, 144 patients were included in this study. The low-BMI group (BMI < 18.5 kg/m2) had a higher incidence of sputum, Mycobacterium intracellurare infection, and cavitary lesions, in addition to lower blood lymphocyte counts, higher neutrophil-lymphocyte ratios, and a lower prognostic nutritional index (PNI) when compared to the preserved-BMI group (BMI ≥ 18.5 kg/m2). Sixty-six of the 144 patients (45.8%) received treatment. Hemosputum, acid-fast bacillus sputum smear positivity, low lymphocyte counts, a low PNI, and unsuccessful treatment (48.5% vs. 24.2%, p < 0.05) were found to be associated with a low BMI. CONCLUSIONS: A low BMI is associated with cavitary lesions, malnutrition, and unsuccessful treatment in MAC-PD.

Clinical Manifestations of Allergic Bronchopulmonary Aspergillosis without Major Features of Asthma Diagnosed by the New Criteria in Japan.

Allergic bronchopulmonary aspergillosis (ABPA) is a severe form of asthma in which structural airway destruction occurs due to a hypersensitivity reaction to fungi. A 25-year-old man without any major features of asthma had lung infiltration with dilatation of the central bronchus, high-attenuation mucus with histological eosinophilic invasion, fungi detected on cultures, and positive Aspergillus-specific immunoglobulin E (IgE) and precipitating antibody of Aspergillus, with a significant elevation of blood eosinophils and slightly increased total IgE. He recovered rapidly with systemic corticosteroid therapy without recurrence over 1-year follow-up and an increased forced expiratory volume in one second, which supported the possibility of ABPA without any major features of asthma.

Clinical features of Japanese patients with exacerbations of chronic obstructive pulmonary disease.

BACKGROUND: Exacerbations are critical events in chronic pulmonary obstructive disease (COPD). The frequency of COPD exacerbations is associated with the prognosis, including mortality, but no useful biomarker has been established. METHODS: The present retrospective study investigated 481 COPD patients. Clinical features in the stable period were compared between patients who experienced severe exacerbation (n = 88, 18.3%) and those who never experienced severe exacerbation (n = 393, 81.7%). In the patients who experienced exacerbations, clinical features were also compared between frequent exacerbators (exacerbation rate ≥ 2 times/year, n = 27, 30.7%) and infrequent exacerbators (1 time/year, n = 61, 69.3%). RESULTS: Compared to COPD patients who never experienced exacerbations, body mass index (BMI), serum albumin, and pulmonary functions were significantly lower, and the cardiovascular disease comorbidity rate, COPD assessment test score, modified Medical Research Council dyspnea scale, and use of long-term oxygen therapy, long-acting ß2 adrenergic agonist therapy, inhaled corticosteroid therapy, and macrolide therapy were significantly higher in COPD patients with exacerbations (all p < 0.01). In patients who experienced exacerbations, frequent exacerbators had significantly lower % forced expiratory volume in 1.0 s and a higher risk of critical exacerbations, percentage of blood eosinophils, history of mechanical ventilation use, and use of long-term oxygen therapy and of macrolide therapy than infrequent exacerbators (all p < 0.01). On multivariate analysis, the percentage of blood eosinophils was the parameter most correlated with exacerbation frequency (ß value [95% confidence interval] 1.45 [1.12-1.88], p < 0.01). CONCLUSION: Blood eosinophil in the stable period is the factor most correlated with the frequency of severe exacerbations. TRIAL REGISTRATION: The patients in this study was registered retrospectively.

Biomarkers for Overweight in Adult-Onset Asthma.

PURPOSE: Overweight and obesity are associated with one of the severe phenotypes of asthma, with an increased rate of exacerbations, low level of lung function, and reduced response to corticosteroid therapy. The present study focused on identifying useful biomarkers of severity in overweight patients with adult-onset asthma using real-world data. PATIENTS AND METHODS: A total of 56 patients with adult-onset asthma who visited Saga University Hospital between 2018 and 2019 were retrospectively reviewed. Overweight was defined as a body mass index (BMI) greater than 25 kg/m2. Blood eosinophils, cytokines, and chemokines were compared between non-overweight asthma and overweight asthma patients. RESULTS: Overweight asthma patients had a higher annual exacerbation rate, lower pulmonary function even when treated frequently with high-dose inhaled corticosteroids, and a significantly lower percentage of eosinophils and lower eosinophil count compared to non-overweight asthma patients (p<0.01, p=0.03). Moreover, the percentage of eosinophils was significantly negatively correlated with BMI (ρ=-0.38, p<0.01) (Figure 1). On serum cytokine and chemokine analyses, the overweight asthma group included significantly more patients with a lower level of tissue growth factor α (TGF-α) (1.1 pg/mL) and higher levels of hsIL-6 (2.5 pg/mL), RANTES/CCL5 (298.5 pg/mL), and vascular endothelial growth factor A (VEGF-A) (63.7 pg/mL), than the non-overweight asthma group (p=0.02, p<0.01, p=0.02, p=0.01, respectively). CONCLUSION: The present study showed that overweight patients with adult-onset asthma were characterized by a higher rate of annual exacerbations and worse lung function despite treatment with high-dose inhaled corticosteroids and lower blood eosinophil counts than non-overweight patients with asthma. On blood cytokine and chemokine analyses, a low level of TGF-α and high levels of hsIL-6, RANTES/CCL5, and VEGF-A might be biomarkers reflecting the pathophysiology in overweight patients with asthma.

The Nonantibiotic Macrolide EM900 Attenuates House Dust Mite-Induced Airway Inflammation in a Mouse Model of Obesity-Associated Asthma.

INTRODUCTION: Obesity-associated asthma is characterized by type 2-low airway inflammation. We previously showed that EM900, which is a 12-membered nonantibiotic macrolide, suppressed airway inflammation in a mouse model of asthma exacerbation. The aim of this study was to clarify the effects of EM900 in obesity-associated asthma. METHODS: BALB/c mice were fed a low-fat diet (LFD) or high-fat diet (HFD). Mice were intranasally sensitized and challenged with house dust mites (HDMs) and were orally administered EM900. Airway inflammation was assessed using inflammatory cells in bronchoalveolar lavage (BALF). Cytokines were examined by ELISA in lung tissues. Lung interstitial macrophages (CD45+, CD11clow, CD11b+, and Ly6c-) were counted by flow cytometry in single cells from lung tissues. RESULTS: Body weight increased significantly in the HFD compared with the LFD group. The total cell count and numbers of neutrophils and eosinophils in BALF were significantly suppressed by EM900 administration in the HFD-HDM group. The levels of interleukin (IL)-17A were increased in the HFD-HDM group compared with the LFD-HDM group, although the difference did not reach statistical significance. The levels of IL-17A, macrophage inflammatory protein 2, IL-1ß, IL-5, and regulated on activation, normal T cell expressed and secreted in lung tissue were significantly suppressed by EM900 administration in the HFD-HDM group. The percentage of interstitial macrophages in lungs was significantly decreased by EM900 administration in the HFD-HDM group. CONCLUSION: Both type 2 and type 2-low airway inflammation were attenuated by EM900 in this obesity-associated asthma model. These results show that EM900 might be a candidate agent for the treatment of obesity-associated asthma.

Paraneoplastic Limbic Encephalitis Complicated with Small Cell Lung Cancer at the Time of Recurrence.

Paraneoplastic limbic encephalitis (PLE) is a rare neurologic disorder that can complicate various malignancies, including lung cancer. PLE is most frequently found the initial presentation of lung cancer. In this study, we reported the case of a 74-year-old Japanese woman who developed PLE after partial remission of small cell lung cancer (SCLC) by first-line systemic chemotherapy. Brain magnetic resonance imaging showed no metastatic tumor or cerebrovascular disease. Anti-glutamic acid decarboxylase (GAD) and anti-amphiphysin antibodies were detected in her serum. She was diagnosed as having PLE related to the recurrence of SCLC and received high-dose glucocorticoid, and sequentially systemic chemotherapy with amrubicin. Unfortunately, these treatments did not improve her disease progression and she died 4 months later. Although PLE rarely occurs at the time of SCLC recurrence, physicians should pay attention to PLE onset even after chemotherapy.

Signet Ring Cell Carcinoma of Unknown Primary Complicated with Pulmonary Tumor Thrombotic Microangiopathy and Krukenberg Tumor.

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare disease that shows hypoxia with severe pulmonary hypertension related to malignant tumor. Diagnosis is difficult due to rapid clinical progression and the need to demonstrate pathological findings from lung biopsy. A 64-year-old woman visited our hospital with hypoxia and pulmonary hypertension. Diffuse granular shadows in the centrilobular area and ground-glass shadows in both lungs and left ovarian tumor were found on radiological imaging. PTTM was suspected, but pulmonary artery blood aspiration by right cardiac catheter failed to detect cancer cells. We could not obtain lung or ovary biopsies because of hypoxia or pulmonary hypertension. The patient died due to respiratory failure. Signet ring cell carcinoma of unknown primary, PTTM, and Krukenberg tumor were diagnosed on autopsy. Since early diagnosis facilitates adequate treatment, physicians should not miss the opportunity for biopsy in cases of suspected PTTM.