Robotics in the diagnosis and staging of lung cancer.

The diagnosis of peripheral small lung lesions by electromagnetic navigational bronchoscopy is still inferior to computed tomography (CT) guided percutaneous transthoracic needle lung biopsy. Robotic bronchoscopy is a new technology that may be a potential breakthrough in the diagnosis of small lung lesions. Real-time tools such as electromagnetic navigation, radial-endobronchial ultrasound, and cone beam CT may further improve the diagnostic yield rate may further improve the diagnostic yield rate. In this article, we reviewed early experience of robotic bronchoscopy for diagnosis and staging of lung cancer.

Postoperative Empyema After Pleurectomy Decortication for Malignant Pleural Mesothelioma.

BACKGROUND: Postoperative empyema after pleurectomy decortication (PDC) for malignant pleural mesothelioma (MPM) is a serious complication that necessitates prolonged hospitalization. This study determined the incidence, risk factors, and prognosis in patients when postoperative empyema develops after PDC. METHODS: The background, type of PDC, neoadjuvant treatment, date of empyema, pleural fluid cultures, treatment after empyema, and prognosis from a series of consecutive 355 patients treated over 9 years at a single high-volume center were investigated. Fisher exact test, Kaplan-Meier estimators, and log-rank test were used to identify significant risk factors for postoperative empyema and compare the overall survival. RESULTS: During the 9-year period, 355 patients (263 men) underwent PDC for MPM at a median age of 69 years. Neoadjuvant therapy was given to 87, and 282 received intraoperative heated chemotherapy. During the study, empyema developed in 24 patients (6.8%). The length of stay of patients with postoperative empyema was significantly longer. Median survival was 11.7 months for patients with postoperative empyema and 21.3 months for patients without empyema (hazard ratio, 1.78; P = .009). Postoperative empyema was associated with male sex, prolonged air leak, and use of prosthetic mesh. CONCLUSIONS: Postoperative empyema after PDC is associated with prolonged length of stay and higher mortality. The rates of this serious postoperative complication might decrease by developing better strategies to avoid prolonged air leak after PDC.

Pleurectomy Decortication in the Treatment of Malignant Pleural Mesothelioma: Encouraging Results and Novel Prognostic Implications Based on Experience in 355 Consecutive Patients.

OBJECTIVE: We report a series of 355 consecutive patients treated over 9 years in a single institution with intended PDC. BACKGROUND: Surgery for MPM has shifted from extra-pleural pneumonectomy to PDC with the goal of MCR. METHODS: Clinical and outcome data were reviewed. Kaplan-Meier estimators and log rank test were used to compare the overall survival, and logistic regression models were used. RESULTS: MCR was achieved in 304. There were 223 males, median age was 69 and histology was epithelioid in 184. The 30 and 90-day mortality were 3.0% and 4.6%.Most complications were low grade. Prolonged air leak in 141, deep venous thrombosis in 64, Atrial fibrillation in 42, chylothorax in 24, Empyema in 23, pneumonia in 21, Hemothorax in 12 and pulmonary embolus in 8. Median/5-year survival were 20.7 months/17.9% in the intent-to-treat cohort and 23.2months/21.2% in the MCR group. The survivals were best for patients with Tlstage and epithelioid histology (69.8months/54.1%). In a multivariable analysis, factors that were found to be associated with longer patient overall survival included epithelioid histology, T stage, quantitative clinical stage/tumor volume staging, adjuvant chemotherapy, intraoperative heated chemo, female sex, and length of stay shorter than 14 days. CONCLUSIONS: PDC is feasible with low mortality and is associated with manageable complication rates. 5-year survival of patients undergoing PDC with MCR in multi-modality setting is approaching 25% depending on quantitative and clinical stage, sex and histological subtype and is better than PDC without- MCR.

Large-scale analysis of BAP1 expression reveals novel associations with clinical and molecular features of malignant pleural mesothelioma.

BRCA1-associated protein-1 (BAP1) expression is commonly lost in several tumors including malignant pleural mesothelioma (MPM). Presence or absence of immunohistochemical BAP1 nuclear staining in tumor cells is currently used for differential diagnosis of MPM. In this study, a large cohort of 596 MPM tumors with available clinical data was analyzed to examine associations of BAP1 staining pattern with clinical and molecular features that may reflect the impact of BAP1 mutation on MPM biology. Cases were classified according to the BAP1 staining pattern of tumor cells. Exome and RNA-sequencing data were available for subsets of cases. Levels of mRNA encoding claudin 15 (CLDN15) and vimentin (VIM) were determined using RT-qPCR on 483 cases to estimate the relative proportions of epithelial-like and mesenchymal-like components in each tumor. Four BAP1 staining patterns were observed: single-pattern nuclear staining (36%), single-pattern cytoplasmic staining (25%), single-pattern absent staining (12%), and combinations of these staining patterns (27%). This study confirmed prior reports that nuclear BAP1 is more frequently associated with wild-type BAP1 and sarcomatoid histology. However, no associations between BAP1 staining pattern(s) and mutations in specific protein domains and/or mutation type were observed. BAP1 staining patterns were significantly associated (p < 0.001) with BAP1 gene expression, MPM histologic subtypes, molecular clusters, and markers of epithelial-to-mesenchymal transition. Frequent observation of combinations of BAP1 staining patterns in MPM tumors indicated intra-tumoral heterogeneity of BAP1 status. Cytoplasmic BAP1 staining was identified as a putative indicator of favorable prognosis in non-epithelioid MPM. In conclusion, novel significant associations among different BAP1 staining patterns and subgroups of MPM tumors were observed, suggesting that the role of BAP1 in tumor progression may be more complex than its presumed tumor suppressor function. Cytoplasmic staining was identified as a putative indicator of favorable prognosis in non-epithelioid MPM, potentially addressing a critical need in clinical decision-making in this disease. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Routine surveillance for diagnosis of venous thromboembolism after pleurectomy for malignant pleural mesothelioma.

OBJECTIVE: The purpose of this study was to determine the incidence of venous thromboembolism and utility of a routine surveillance program in patients undergoing surgery for mesothelioma. METHODS: Patients undergoing pleurectomy from May 2016 to August 2018 were included. A standardized surveillance program to look for venous thromboembolism in this group included noninvasive studies every 7 days postoperatively or earlier if symptomatic. All patients received external pneumatic compression sleeves in addition to prophylactic heparin. If deep vein thrombosis or pulmonary embolus was discovered, heparin drip was initiated until conversion to therapeutic anticoagulation. RESULTS: A total of 100 patients underwent pleurectomy for mesothelioma. Seven patients were found to have preoperative deep vein thrombosis, and as such only 93 patients were included for analysis. The median age of patients at surgery was 71 years (30-85 years). During the study, 30 patients (32%) developed evidence of thrombosis; 20 patients (22%) developed only deep vein thrombosis without embolism, 3 patients (3%) developed only pulmonary embolism, and 7 patients (7%) developed both deep vein thrombosis and pulmonary embolus. Of the 27 patients who developed deep vein thrombosis, 9 (33%) were asymptomatic at the time of diagnosis, and none of these developed a pulmonary embolus or other bleeding complications. There were 2 (2%) events of major postoperative bleeding related to therapeutic anticoagulation. CONCLUSIONS: The incidence of venous thromboembolism is high (32%) among patients undergoing surveillance after pleurectomy for mesothelioma. Up to 33% of patients with deep vein thrombosis are asymptomatic at the time of diagnosis, and the incidence of complications related to anticoagulation is low. Routine surveillance may be useful to diagnose and treat deep vein thrombosis before it progresses to symptomatic or fatal pulmonary embolus.

The role of ERp44 in maturation of serotonin transporter protein.

In heterologous and endogenous expression systems, we studied the role of ERp44 and its complex partner endoplasmic reticulum (ER) oxidase 1-α (Ero1-Lα) in mechanisms regulating disulfide bond formation for serotonin transporter (SERT), an oligomeric glycoprotein. ERp44 is an ER lumenal chaperone protein that favors the maturation of disulfide-linked oligomeric proteins. ERp44 plays a critical role in the release of proteins from the ER via binding to Ero1-Lα. Mutation in the thioredoxin-like domain hampers the association of ERp44C29S with SERT, which has three Cys residues (Cys-200, Cys-209, and Cys-109) on the second external loop. We further explored the role of the protein chaperones through shRNA knockdown experiments for ERp44 and Ero1-Lα. Those efforts resulted in increased SERT localization to the plasma membrane but decreased serotonin (5-HT) uptake rates, indicating the importance of the ERp44 retention mechanism in the proper maturation of SERT proteins. These data were strongly supported with the data received from the N-biotinylaminoethyl methanethiosulfonate (MTSEA-biotin) labeling of SERT on ERp44 shRNA cells. MTSEA-biotin only interacts with the free Cys residues from the external phase of the plasma membrane. Interestingly, it appears that Cys-200 and Cys-209 of SERT in ERp44-silenced cells are accessible to labeling by MTSEA-biotin. However, in the control cells, these Cys residues are occupied and produced less labeling with MTSEA-biotin. Furthermore, ERp44 preferentially associated with SERT mutants (C200S, C209S, and C109A) when compared with wild type. These interactions with the chaperone may reflect the inability of Cys-200 and Cys-209 SERT mutants to form a disulfide bond and self-association as evidenced by immunoprecipitation assays. Based on these collective findings, we hypothesize that ERp44 together with Ero1-Lα plays an important role in disulfide formation of SERT, which may be a prerequisite step for the assembly of SERT molecules in oligomeric form.

Down-regulation of the serotonin transporter in hyperreactive platelets counteracts the pro-thrombotic effect of serotonin.

An elevated plasma concentration of serotonin ([5-HT]) is a common feature of cardiovascular disease often associated with enhanced platelet activation and thrombosis. Whether elevated in vivo plasma 5-HT per se represents an independent risk factor for platelet hyperreactivity or only is an epiphenomenon of cardiovascular disease is poorly understood. We examined in vitro and in vivo platelet function following a 24h elevation of plasma [5-HT] in mice. In vivo administration of 5-HT using osmotic minipumps increased plasma [5-HT] in treated mice compared to control mice instrumented with saline loaded pumps. 5-HT infusion did not increase systolic blood pressure, but markers of platelet activation including P-selectin and (PE)Jon/A staining were increased and these findings coincided with the enhanced aggregation of isolated platelets in response to type I fibrillar collagen. Tail bleeding times and the time to occlusion following chemical damage to the carotid artery were shortened in 5-HT-infused mice. 5-HT-infused mice were treated with paroxetine (Prx) to block 5-HT uptake via the serotonin transporter (SERT). Prx lowered platelet [5-HT] and attenuated platelet activation and aggregation. These results and our biochemical indices of enhanced 5-HT intracellular signaling in the platelets of 5-HT-infused mice reveal a mechanistic link between elevated plasma [5-HT], abnormal intracellular 5-HT signaling and accentuated platelet aggregation. Although a down-regulation of the serotonin transporter (SERT) on the platelet surface may counteract the pro-thrombotic influence of elevated plasma [5HT], this compensatory mechanism may fail to prevent the increased thrombotic risk caused by elevated plasma [5-HT].