Pulmonary actinomycosis mimicking lung cancer on 18F-fluorodeoxyglucose positron emission tomography: a case report.

BACKGROUND: Pulmonary actinomycosis is a chronic disease characterized by abscess formation, draining sinuses, fistulae, and tissue fibrosis. It can mimic other conditions, particularly malignant and granulomatous diseases, and is perhaps extremely challenging to diagnose. CASE PRESENTATION: A 64-year-old Japanese man presented with 6-week history of a painful solid lump in the chest wall. Chest computed tomography scan revealed a mass-like consolidation in the left upper lobe, with rib erosion and direct extension into the anterior chest wall. 18F-fluorodeoxyglucose positron emission tomography scan showed increased metabolic activity in the mass, which is indicative of primary lung cancer. The bronchoscopy and computed tomography scan-guided transthoracic biopsy results were considered nondiagnostic. Finally, the patient was diagnosed with pulmonary actinomycosis via surgical resection. He completed an 8-week course of antibiotic therapy and experienced no recurrence. CONCLUSIONS: There is no difference in positron emission tomography/computed tomography scan findings between actinomycosis and malignancy. Therefore, pulmonary actinomycosis should be considered in the differential diagnosis of cases involving intensive activity on 18F-fluorodeoxyglucose positron emission tomography scan.

Intravascular lymphoma masquerading as septic shock.

Intravascular lymphoma (IVL) is a rare type of extranodal lymphoma that selectively affects small blood vessels. We report a patient who presented with dyspnea and weight loss as well as refractory shock and multiple-organ dysfunction. The postmortem revealed disseminated involvement of an IVL but no evidence of infection.

An EGFR T790M-mutated lung adenocarcinoma undergoing large-cell neuroendocrine carcinoma transformation after osimertinib therapy: a case report.

BACKGROUND: Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, is selective for both epidermal growth factor receptor tyrosine kinase inhibitor-sensitizing and T790M resistance mutations. Almost all patients who initially respond to an epidermal growth factor receptor tyrosine kinase inhibitor subsequently report disease progression. Epidermal growth factor receptor-dependent resistance mechanisms, bypass pathway activation, and histological transformation have been reported with osimertinib therapy. CASE PRESENTATION: We report a case of a 64-year-old Asian man with epidermal growth factor receptor T790M-positive adenocarcinoma that transformed to epidermal growth factor receptor T790M-negative large-cell neuroendocrine carcinoma after osimertinib therapy. A prompt rebiopsy revealed a rare mechanism of resistance to epidermal growth factor receptor tyrosine kinase inhibitor, and subsequently treatment with carboplatin and etoposide was effective. CONCLUSIONS: Despite the promising emergence of circulating tumoral DNA testing, this case report emphasizes the importance of rebiopsy of a progressive epidermal growth factor receptor-mutant tumor.

Pulmonary mucosa-associated lymphoid tissue lymphoma mimicking lung cancer.

Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is the most frequent subset of primary pulmonary lymphoma. MALT lymphoma may manifest as a solid mass, mimicking lung cancer.

Repressive role of stabilized hypoxia inducible factor 1α expression on transforming growth factor ß-induced extracellular matrix production in lung cancer cells.

Activation of transforming growth factor ß (TGF-ß) combined with persistent hypoxia often affects the tumor microenvironment. Disruption of cadherin/catenin complexes induced by these stimulations yields aberrant extracellular matrix (ECM) production, characteristics of epithelial-mesenchymal transition (EMT). Hypoxia-inducible factors (HIF), the hallmark of the response to hypoxia, play differential roles during development of diseases. Recent studies show that localization of cadherin/catenin complexes at the cell membrane might be tightly regulated by protein phosphatase activity. We aimed to investigate the role of stabilized HIF-1α expression by protein phosphatase activity on dissociation of the E-cadherin/ß-catenin complex and aberrant ECM expression in lung cancer cells under stimulation by TGF-ß. By using lung cancer cells treated with HIF-1α stabilizers or carrying doxycycline-dependent HIF-1α deletion or point mutants, we investigated the role of stabilized HIF-1α expression on TGF-ß-induced EMT in lung cancer cells. Furthermore, the underlying mechanisms were determined by inhibition of protein phosphatase activity. Persistent stimulation by TGF-ß and hypoxia induced EMT phenotypes in H358 cells in which stabilized HIF-1α expression was inhibited. Stabilized HIF-1α protein expression inhibited the TGF-ß-stimulated appearance of EMT phenotypes across cell types and species, independent of de novo vascular endothelial growth factor A (VEGFA) expression. Inhibition of protein phosphatase 2A activity abrogated the HIF-1α-induced repression of the TGF-ß-stimulated appearance of EMT phenotypes. This is the first study to show a direct role of stabilized HIF-1α expression on inhibition of TGF-ß-induced EMT phenotypes in lung cancer cells, in part, through protein phosphatase activity.

Birt-Hogg-Dubé syndrome in the elderly.

We present the case of a 73-year-old woman who developed pneumothorax for the first time that was a clinical clue to the diagnosis of Birt-Hogg-Dubé (BHD) syndrome. Although younger onset of pneumothorax is more common in BHD syndrome, the characteristic chest CT findings may contribute to the diagnosis of this disorder in spontaneous pneumothorax of the elderly.

IgA nephropathy with diffuse alveolar haemorrhage.

Immunoglobulin (Ig)A nephropathy is the most common cause of primary glomerulonephritis worldwide. While IgA nephropathy has been associated with a variety of other diseases, pulmonary complications are extremely rare. A 58-year-old man presented with a 2-week history of fever and exertional dyspnoea. A chest imaging revealed bilateral consolidation predominantly in upper lungs. Laboratory findings showed elevated serum creatinine with proteinuria and haematuria. Flexible bronchoscopy revealed diffuse alveolar haemorrhage, and IgA nephropathy was confirmed on a renal biopsy. He received prednisone with good effect. This case highlights the need to consider IgA nephropathy in the differential diagnosis of pulmonary renal syndrome.

The Evaluation of Fibrin-Related Markers for Diagnosing or Predicting Acute or Subclinical Venous Thromboembolism in Patients Undergoing Major Orthopedic Surgery.

OBJECTIVE: The cutoff values of fibrin-related markers (FRMs) diagnosing or predicting the occurrence of a venous thromboembolism (VTE) were evaluated. MATERIALS AND METHODS: Fibrin-related markers such as fibrin monomer complex (FMC), D-dimer, and fibrinogen and fibrin degradation products (FDPs) before surgery were measured in 326 patients undergoing orthopedic surgery to diagnose subclinical VTE or predict postoperative VTE. RESULTS: Although the FMC, D-dimer, and FDP levels were all useful for the diagnosis of acute VTE, the FDP level was not useful for diagnosing subclinical VTE or predicting postoperative VTE. The results of several D-dimer assays closely correlated with other D-dimer assays. There were various cutoff ranges for diagnosing or predicting VTE. Some D-dimer assays were useful for diagnosing low levels of D-dimer and others were useful for diagnosing moderate to high D-dimer levels. Increased D-dimer levels were useful for diagnosing acute (cutoff values: 2.0-5.9 µg/mL) or about 10% of subclinical VTE (cutoff values: 3.4-5.3 µg/mL), for predicting about 10% of postoperative VTE (cutoff values: 3.4-5.3 µg/mL), and for excluding VTE. CONCLUSION: Although increased D-dimer levels were useful for diagnosing subclinical VTE and predicting the risk of VTE, there were various cutoff values for the diagnosis or prediction of VTE.

Pulmonary tumor thrombotic microangiopathy successfully treated with corticosteroids: a case report.

BACKGROUND: Pulmonary tumor thrombotic microangiopathy is a special type of tumor thromboembolism. We report the case of a patient who developed pulmonary tumor thrombotic microangiopathy with alveolar hemorrhage. Almost all patients with pulmonary tumor thrombotic microangiopathy die within 1 week of the onset of dyspnea; however, the prognosis in this case was better, with 10 weeks of survival from presentation. CASE PRESENTATION: A 62-year-old Japanese man was referred to our hospital with a 4-week history of dyspnea on exertion and severe pulmonary hypertension. Five years previously, he had undergone distal gastrectomy for gastric cancer. He was afebrile, normotensive, and hypoxemic. A physical examination was unremarkable except for purpura on his upper extremities and trunk. Blood tests showed anemia and disseminated intravascular coagulation. Chest computed tomography revealed diffuse ground-glass opacities with emphysema in his upper lungs, moderate pleural effusions, mediastinal lymphadenopathy, and enlargement of the right ventricle and main pulmonary artery. A computed tomography pulmonary angiogram showed no evidence of pulmonary embolism. Lung perfusion scintigraphy showed multiple segmental defects. Although recurrence of gastric cancer was confirmed from the results of bone marrow biopsy, bronchoscopy was not performed due to bleeding diathesis. He was treated with corticosteroids, antibiotics, and platelet transfusion, following which resolution of the abnormal lung shadows and right ventricular pressure overload along with partial alleviation of respiratory failure was observed. Because of his poor performance status, he was eventually transited to palliative care and died 6 weeks after admission. Necropsy of the lung confirmed the diagnosis of pulmonary tumor thrombotic microangiopathy with alveolar hemorrhage. CONCLUSIONS: Pulmonary tumor thrombotic microangiopathy should be considered in the differential diagnosis of patients with cancer who present with severe pulmonary hypertension. In pulmonary tumor thrombotic microangiopathy, local inflammation in pulmonary microvasculature may contribute to pulmonary hypertension, and regulation of inflammation using corticosteroids may help improve the prognosis.

Impact of mild to moderate COPD on feasibility and prognosis in non-small cell lung cancer patients who received chemotherapy.

Background: Non-small cell lung cancer (NSCLC) is the predominant cause of death in patients with COPD, and the severity of COPD in NSCLC patients is classified mainly as mild to moderate. Most advanced NSCLC patients with mild to moderate COPD are treated with chemotherapy; however, the feasibility for and prognosis after chemotherapy of these patients are not well understood. The aim of this study was to elucidate the impact of mild to moderate COPD on the feasibility for and prognosis after chemotherapy in NSCLC patients. Patients and methods: A retrospective review was performed on 268 NSCLC patients who received first-line chemotherapy from 2009 to 2014 in our institution. Finally, 85 evaluable patients were included in this study. The clinical characteristics, toxicity profile, objective response rate, and prognosis were analyzed and compared between patients with mild to moderate COPD and those without COPD (non-COPD). Results: Forty-three patients were classified as COPD (27 cases mild and 16 cases moderate) and 42 patients as non-COPD. The COPD group were older and had fewer never-smokers than the non-COPD group. The objective response rate did not differ between groups (p=0.14). There was no significant difference in overall survival between COPD and non-COPD groups (15.0 and 17.0 months, log-rank test p=0.57). In the multivariate Cox's proportional hazard model, the adjusted hazard ratio (HRadj) was statistically significant for male sex (HRadj =5.382, 95% CI: 1.496-19.359; p=0.010), pathological diagnosis of adenocarcinoma (HRadj =0.460, 95% CI: 0.223-0.948; p=0.035), and epithelial growth factor receptor negative mutation (HRadj =6.040, 95% CI: 1.158-31.497; p=0.033), but not for the presence of COPD (HRadj =0.661, 95% CI: 0.330-1.325; p=0.24). Toxicity profile in COPD group was favorable, as in the non-COPD group. Conclusion: Mild to moderate COPD did not have a significant deleterious impact on toxicity and prognosis in NSCLC patients.

Comparison of Midterm Outcomes of Minimally Invasive Computer-Assisted vs Minimally Invasive Jig-Based Total Knee Arthroplasty.

BACKGROUND: Minimally invasive surgery (MIS) has perceived advantages in the early postoperative stage for total knee arthroplasty (TKA). It is not clear whether the improved radiographic alignment achieved by computer-assisted navigation surgery (CAS) improves midterm clinical outcomes. The aim of this study was to compare patient outcomes of MIS TKA performed with and without CAS after a minimum follow-up of 7 years. METHODS: Between 2007 and 2009, 50 patients underwent CAS and MIS TKA, and 50 patients underwent jig-based MIS TKA in this prospective study. Ninety-six patients were evaluated after a mean follow-up of 7.7 years, and clinical and radiological evaluations were performed. RESULTS: Midterm results demonstrated that the Knee Society knee score, function score, and range of motion were comparable in the 2 groups. The percentage of patients with the mechanical axis within ±3° of neutral was significantly higher in the CAS group than in the jig-based group (94% vs 79%, respectively; P = .038). No knees had loosening after TKA. However, 1 patient in the CAS group demonstrated late infection 4 years postoperatively. CONCLUSION: CAS did not improve midterm outcomes after MIS TKA compared with jig-based surgery, although CAS reduced outliers in coronal alignment.

Exogenous induction of unphosphorylated PTEN reduces TGFß-induced extracellular matrix expressions in lung fibroblasts.

Transforming growth factor ß (TGFß) plays an important role in regulating aberrant extracellular matrix (ECM) production from alveolar/epithelial cells (AECs) and fibroblasts in pulmonary fibrosis. Although the tumor suppressor gene phosphatase and tensin homologue deleted from chromosome 10 (PTEN) can negatively control many TGFß-activated signaling pathways via the phosphatase activity, hyperactivation of the TGFß-related signaling pathways is often observed in fibrosis. Loss of PTEN expression might cause TGFß-induced ECM production. In addition, TGFß was recently shown to induce loss of PTEN enzymatic activity by phosphorylating the PTEN C-terminus. Therefore, we hypothesized that exogenous transfer of unphosphorylated PTEN (PTEN4A) might lead to reduce TGFß-induced ECM expression in not only epithelial cells but also fibroblasts. Adenovirus-based exogenous PTEN4A induction successfully reduced TGFß-induced fibronectin expression and retained ß-catenin at the cell membrane in human epithelial cells. Exogenous unphosphorylated PTEN also attenuated TGFß-induced ECM production and inhibited TGFß-induced ß-catenin translocation in a human fibroblast cell line and in mouse primary isolated lung fibroblasts. Conversely, TGFß-induced α-smooth muscle actin expression did not seem to be inhibited in these fibroblasts. Our data suggest that exogenous administration of unphosphorylated PTEN might be a promising strategy to restore TGFß-induced loss of PTEN activity and reduce aberrant TGFß-induced ECM production from epithelial cells and fibroblasts in lung fibrosis as compared with wild-type PTEN induction.

Factors associated with symptomatic pseudotumors following metal-on-metal total hip arthroplasty.

BACKGROUND: Pseudotumors associated with metal-on-metal hips can be symptomatic or asymptomatic. The purpose of this study was to identify the characteristics of pseudotumors associated with pain. METHODS: A total of 239 large-diameter, metal-on-metal total hip arthroplasties (THAs) were performed in 222 patients. Screening for pseudotumors was performed using magnetic resonance imaging (MRI) in all patients who underwent metal-on-metal THA, and 57 patients with 62 affected hips showed pseudotumors. There were 45 women with 49 hips and 12 men with 13 hips affected, with a mean age of 64 years and a mean body mass index (BMI) of 23.9 kg/m2. Sixteen hips had symptomatic pseudotumors with pain, and 46 hips were asymptomatic. Pseudotumor size was determined. The anatomical position of pseudotumors was divided into anterior position and posterolateral position. Types of pseudotumors were divided into two types: cystic type; and mixed solid cystic and solid type without a cystic component. The follow-up study of pseudotumors was determined using MRI in 33 patients. The serum cobalt and chromium ion levels were measured in 38 patients after unilateral THA. Univariate and multivariate analyses were performed comparing symptomatic and asymptomatic patients to identify the characteristics of symptomatic pseudotumors. RESULTS: The mean BMI was 25.4 kg/m2 in symptomatic patients and 23.4 kg/m2 in asymptomatic patients; a higher BMI was associated with symptoms (P = 0.036). Symptomatic pseudotumors were significantly larger (three-fold) than asymptomatic pseudotumors (1812 mm2 vs 642 mm2, P = 0.003). Pseudotumors located in the anterior position were associated with symptoms (P = 0.032), and mixed solid cystic and solid type pseudotumors were associated with symptoms (P = 0.007). A multivariate analysis showed significant differences only in size (R 2 = 0.298, P = 0.031). No asymptomatic patients with pseudotumors became symptomatic during the follow-up period of MRI evaluation. CONCLUSION: Larger size was a significant factor for pain on multivariate analysis.

Hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers.

BACKGROUND: Persistent hypoxia stimulation, one of the most critical microenvironmental factors, accelerates the acquisition of epithelial-mesenchymal transition (EMT) phenotypes in lung cancer cells. Loss of phosphatase and tensin homologue deleted from chromosome 10 (PTEN) expression might accelerate the development of lung cancer in vivo. Recent studies suggest that tumor microenvironmental factors might modulate the PTEN activity though a decrease in total PTEN expression and an increase in phosphorylation of the PTEN C-terminus (p-PTEN), resulting in the acquisition of the EMT phenotypes. Nevertheless, it is not known whether persistent hypoxia can modulate PTEN phosphatase activity or whether hypoxia-induced EMT phenotypes are negatively regulated by the PTEN phosphatase activity. We aimed to investigate hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers. METHODS: Western blotting was performed in five lung cancer cell lines to evaluate total PTEN expression levels and the PTEN activation. In a xenograft model of lung cancer cells with endogenous PTEN expression, the PTEN expression was evaluated by immunohistochemistry. To examine the effect of hypoxia on phenotypic alterations in lung cancer cells in vitro, the cells were cultured under hypoxia. The effect of unphosphorylated PTEN (PTEN4A) induction on hypoxia-induced EMT phenotypes was evaluated, by using a Dox-dependent gene expression system. RESULTS: Lung cancer cells involving the EMT phenotypes showed a decrease in total PTEN expression and an increase in p-PTEN. In a xenograft model, loss of PTEN expression was observed in the tumor lesions showing tissue hypoxia. Persistent hypoxia yielded an approximately eight-fold increase in the p-PTEN/PTEN ratio in vitro. PTEN4A did not affect stabilization of hypoxia-inducible factor 1α. PTEN4A blunted hypoxia-induced EMT via inhibition of ß-catenin translocation into the cytoplasm and nucleus. CONCLUSION: Our study strengthens the therapeutic possibility that compensatory induction of unphosphorylated PTEN may inhibit the acquisition of EMT phenotypes in lung cancer cells under persistent hypoxia.

Fibrin-related markers for diagnosing acute-, subclinical-, and pre-venous thromboembolism in patients with major orthopedic surgery.

Venous thromboembolism (VTE) is a common complication in patients who have undergone major orthopedic surgery, but there are few predictors of VTE after major orthopedic surgery treated with an anticoagulant. We measured levels of fibrin-related markers (FRMs), such as D-dimer, soluble fibrin (SF), and fibrinogen and fibrin degradation products (FDPs) in 66 patients with acute-phase VTE, and 367 patients undergoing major orthopedic surgery. Plasma FDP, D-dimer, and SF levels were significantly higher in patients with acute VTE, but only FDP and D-dimer levels were significantly higher in subclinical VTE. Adequate cut-off levels of D-dimer were 2.2 µg/ml for diagnosing acute VTE and 1.5 µg/ml for diagnosing subclinical VTE. D-dimer of less than 1.9 or 0.7 µg/ml ruled out acute VTE or subclinical VTE. D-dimer of more than 1.3 µg/ml preoperatively showed a moderate risk for postoperative VTE. Measurement of FRMs is useful for evaluating the risk of subclinical or postoperative VTE in patients with major orthopedic surgery. In particular, FDP is the most valuable marker for diagnosing acute VTE, whereas D-dimer is the most valuable for diagnosing subclinical VTE or predicting VTE.

Comparison of three different anti-Xa assays in major orthopedic surgery patients treated with fondaparinux.

Anti-Xa assays are useful for monitoring the effects of selective anti-Xa drugs, such as fondaparinux, in the prophylaxis of deep vein thrombosis. In the present study, anti-Xa activity was measured using three different assays, Testzym(®) Heparin S, STA(®)-Liquid Anti-Xa and HemosIL(®) Liquid Heparin. Anti-Xa activity in each assay gradually increased from day one after administration to day eight, and still remained on day 15. Although there were significant differences in anti-Xa activity among the three assays, the activity showed significant correlation across assays. There were no significant differences in the anti-Xa activity between patients with and without DVT or between patients with and without massive bleeding on day one before and after administration, day four, day eight and day 15. Anti-Xa activity in each assay was weakly correlated with antithrombin (AT) activity. The AT activity in patients were significantly higher on days four, eight and 15 compared with day one before and after administration, suggesting that AT activity increases following the administration of fondaparinux. The three anti-Xa assay kits tested are useful for monitoring fondaparinux treatment in orthopedic surgery patients.

Direct regulation of transforming growth factor ß-induced epithelial-mesenchymal transition by the protein phosphatase activity of unphosphorylated PTEN in lung cancer cells.

Transforming growth factor ß (TGFß) causes the acquisition of epithelial-mesenchymal transition (EMT). Although the tumor suppressor gene PTEN (phosphatase and tensin homologue deleted from chromosome 10) can negatively regulate many signaling pathways activated by TGFß, hyperactivation of these signaling pathways is observed in lung cancer cells. We recently showed that PTEN might be subject to TGFß-induced phosphorylation of its C-terminus, resulting in a loss of its enzyme activities; PTEN with an unphosphorylated C-terminus (PTEN4A), but not PTEN wild, inhibits TGFß-induced EMT. Nevertheless, whether or not the blockade of TGFß-induced EMT by the PTEN phosphatase activity might be attributed to the unphosphorylated PTEN C-terminus itself has not been fully determined. Furthermore, the lipid phosphatase activity of PTEN is well characterized, whereas the protein phosphatase activity has not been determined. By using lung cancer cells carrying PTEN domain deletions or point mutants, we investigated the role of PTEN protein phosphatase activities on TGFß-induced EMT in lung cancer cells. The unphosphorylated PTEN C-terminus might not directly retain the phosphatase activities and repress TGFß-induced EMT; the modification that keeps the PTEN C-terminus not phosphorylated might enable PTEN to retain the phosphatase activity. PTEN4A with G129E mutation, which lacks lipid phosphatase activity but retains protein phosphatase activity, repressed TGFß-induced EMT. Furthermore, the protein phosphatase activity of PTEN4A depended on an essential association between the C2 and phosphatase domains. These data suggest that the protein phosphatase activity of PTEN with an unphosphorylated C-terminus might be a therapeutic target to negatively regulate TGFß-induced EMT in lung cancer cells.

Longitudinal magnetic resonance imaging of pseudotumors following metal-on-metal total hip arthroplasty.

The purpose of the study was to determine the natural history of pseudotumors following metal-on-metal total hip arthroplasty (THA) using magnetic resonance imaging (MRI). Initial MRI was conducted at a mean of 36months postoperatively. Follow-up MRI was performed at a mean of 20months after the detection of 24 asymptomatic pseudotumors. Pseudotumor size was determined on MRI. The mean pseudotumor size changed from 729mm(2) to 877mm(2). Pseudotumors increased in size in eight and decreased in six. Ten hips showed no changes. The bigger the pseudotumor size, the more likely the size would increase. In conclusion, pseudotumors frequently change in size. A single MRI study in the clinical decision-making process should be avoided and a longitudinal study should be performed.