A simple size-tailored algorithm for the removal of chest drain following minimally invasive lobectomy: a prospective randomized study.

BACKGROUND: The pleural space can resorb 0.11-0.36 ml/kg of body weight/hour (h) per hemithorax. There are only a limited number of studies on thresholds for chest drain removal (CDR) and all are based on arbitrary amounts, for example, 300 ml/day. We studied an individualized size-based threshold for CDR-specifically 5 ml/kg, a simple, easily applicable measure. METHODS: This is a single-center prospective randomized trial enrolling 80 patients undergoing VATS lobectomy. There were two groups: an experimental (E) group, in which once the daily output went down to 5 ml/kg the chest drain was removed and a control (C) group, with chest drain removal as per our current practice of less than 250 ml/day. RESULTS: The groups did not differ in pre- and peri- and postoperative characteristics, except for chest drain duration (mean, SD 2.02 ± 0.97 vs. 3.25 ± 1.39 days, p < 0.001) and length of hospital stay (median, IQR 4.5; 3 vs. 6; 2.75 days, p = 0.008) in favor of E group. The re-intervention rate was the same in both groups (once in each group). CONCLUSION: The new threshold for chest drain removal following thoracoscopic lobectomy of 5 ml/kg/d leads to both shorter chest drainage and hospital stay without apparent increase in morbidity. (Clinical registration number: DRKS00014252).

Presence of pleomorphic features but not growth patterns improves prognostic stratification of epithelioid malignant pleural mesothelioma by 2-tier nuclear grade.

AIMS: Nuclear grade has been recently validated as a powerful prognostic tool in epithelioid malignant pleural mesothelioma (E-MPM). In other studies histological parameters including pleomorphic features and growth patterns were also shown to exert prognostic impact. The primary aims of our study are (i) externally validate the prognostic role of pleomorphic features in E-MPM and (ii) investigate if evaluating growth pattern in addition to 2-tier nuclear grade improves prognostication. METHODS AND RESULTS: 614 consecutive cases of E-MPM from our institution over a period of 15 years were retrospectively reviewed, of which 51 showed pleomorphic features. E-MPM with pleomorphic features showed significantly worse overall survival compared to those without (5.4 versus 14.7 months). Tumours with predominantly micropapillary pattern showed the worst survival (6.2 months) followed by solid (10.5 months), microcystic (15.3 months), discohesive (16.1 months), trabecular (17.6 months) and tubulo-papillary (18.6 months). Sub-classification of growth patterns into high grade (solid, micropapillary) and low grade (all others) led to good separation of overall survival (10.5 versus 18.0 months) but did not predict survival independent of 2-tier nuclear grade. A composite score comprised of growth pattern and 2-tier nuclear grade did not improve prognostication compared with nuclear grade alone. Intra-tumoural heterogeneity in growth patterns is ubiquitous. CONCLUSIONS: Our findings support the incorporation of E-MPM with pleomorphic features in the epithelioid subtype as a highly aggressive variant distinct from 2-tier nuclear grade. E-MPM demonstrates extensive heterogeneity in growth pattern but its evaluation does not offer additional prognostic utility to 2-tier nuclear grade.

Follicular dendritic cell tumour/sarcoma: a commonly misdiagnosed tumour in the thorax.

AIMS: Follicular dendritic cell sarcoma is a rare tumour reported to occur occasionally in association with the hyaline-vascular type of Castleman's disease (HVCD). Most cases arise in lymph nodes, although extranodal presentation is described. METHODS AND RESULTS: Clinical, radiological and histological characteristics, including diagnosis on pre-resection material, were assessed in seven intrathoracic cases from five males and two females with a median age of 38 years. Clinical symptoms were related to mass location, six cases presenting within central and/or posterior mediastinal compartments and one within the lungs. Positron emission tomography-computed tomography demonstrated marked fluoro-deoxy-glucose avidity and the prominent vessels traversing the lesions. Four of six cases (67%) were misdiagnosed initially. HVCD was present in three cases. Two cases with high mitotic rates recurred after resection. All were positive for at least one of the follicular dendritic cell markers (CD21, CD35 and CD23). Six of seven cases (86%) show cyclin D1 expression ranging from 5% to 90%. CONCLUSIONS: Follicular dendritic cell sarcoma is often misdiagnosed on biopsy and pathologists need to be aware of the tumour to request the relevant immunohistochemistry, especially in masses presenting in the central/posterior mediastinum with high vascularity and standardized uptake values. Background HVCD appears more common than previously thought.

Test performance of PET-CT for mediastinal lymph node staging of pulmonary carcinoid tumours.

Positron emission tomography-CT (PET-CT) is one of the initial mediastinal staging modality for non-small cell lung cancer; however, the clinical utility in carcinoid tumours is uncertain. We sought to determine the test performance of PET-CT for mediastinal lymph node staging of pulmonary carcinoid tumours. We collated data from seven institutions, performing a retrospective search on pathological databases for a consecutive series of patients who underwent thoracic surgery (with lymph nodal dissection) for carcinoid tumours with preoperative PET-CT staging. PET-CT results were compared with the reference standard of pathologic results obtained from lymph node dissection and test performance reported using sensitivity and specificity. From November 1999 to January 2013, 247 patients from seven institutions underwent surgery for carcinoid tumours with a corresponding preoperative PET-CT scan. The mean age of the patients was 61 (SD 15, range 73) and 84 were male patients (34%). The pathologic subtype was typical carcinoid in 217 patients (88%) and atypical carcinoid in 30 patients (12%). Results from lymph node dissection were obtained in 207 patients. The calculated sensitivity and specificity of PET-CT to identify mediastinal lymph node disease was 33% (95% CI 4% to 78%) and 94% (95% CI 89% to 97%), respectively. Our results indicate that PET-CT has a poor sensitivity but good specificity to detect the presence of mediastinal lymph node metastases in pulmonary carcinoid tumours. Mediastinal lymph node metastases cannot be ruled out with negative PET-CT uptake, and if the absence of mediastinal lymph node disease is a prerequisite for directing management, tissue sampling should be undertaken.

Type A and AB thymomas: histological features associated with increased stage.

AIMS: The current WHO classification of thymic epithelial neoplasms describes type A and type AB thymomas as behaving 'like benign neoplasms'. However, recent published data suggest that rare cases may show more aggressive behaviour. The aim of this study was to assess the frequency of atypical cases, and to determine whether atypia is associated with more advanced disease. METHODS AND RESULTS: One hundred and twenty-one thymomas (type A, n = 68; type AB, n = 53) were retrospectively reviewed for 'atypical' features (nuclear pleomorphism, mitotic activity, and necrosis). Logistic regression was used to ascertain the association with increasing Masaoka-Koga stage. Where available, follow-up data were also reviewed. There were 72 stage I, 42 stage II, five stage III and two stage IV tumours. Only the presence of necrosis showed a significant association with increased stage in univariate and multivariate analysis. Nuclear atypia and increased mitotic activity were not associated with increasing stage of disease. CONCLUSIONS: Our data support the concept of there being more aggressive atypical variants of both type A and type AB thymoma, and suggest that the presence of necrosis could be used to predict aggressive behaviour.

Surgical approaches for lung volume reduction in emphysema.

Lung volume reduction surgery (LVRS) for chronic obstructive pulmonary disease (COPD) is recommended in both British and international guidelines because trials have shown improvement in survival in selected patients with poor baseline exercise capacity and upper lobe-predominant emphysema. Despite this, few procedures are carried out, possibly because of historical concerns about high levels of morbidity and mortality associated with the operation. The authors reviewed data on lung volume reduction procedures at their institution between January 2000 and September 2012. There were no deaths within 90 days of unilateral LVRS (n = 81), bullectomy (n = 20) or intracavity drainage procedures (n = 14). These data suggest that concerns about surgical mortality should not discourage LVRS in selected patients with COPD, provided that it is undertaken within a multidisciplinary team environment involving appropriate patient selection.

Secondary vascular changes in pulmonary sequestrations.

AIMS: Whilst parenchymal changes in pulmonary sequestrations are well described, there are comparatively little data on associated vascular changes and their extent. The aim of this study was to retrospectively review morphological changes within sequestrations, concentrating on vascular changes and associations with clinical parameters. METHODS AND RESULTS: Twenty-seven resected cases of sequestrations (intralobar n = 20, extralobar n = 7) showed a male predominance (n = 16) and an age range of 2 months-60 years (average 13 years). Plexogenic vascular changes (medial hypertrophy and intimal fibrosis) were seen in 15 of 27 cases, as well as plexiform lesions in seven cases. Patients with plexogenic changes had a higher mean age compared with those lacking vascular changes (19 versus 6 years) and were more commonly female. Respiratory tract infections were associated solely with intralobar sequestrations. No other associations between presenting symptoms and histopathological parameters were identified. Adjacent lung showed lesser plexogenic changes in six of 22 intralobar cases. There were features of type 2 congenital cystic adenomatoid lesions in 63% of cases. Dissection of the supplying systemic artery (n = 1), intralesional aspergilloma (n = 1) and coexistent lymphangiomatosis (n = 1) were also identified. CONCLUSIONS: Hypertensive vascular changes are not uncommon in both intrapulmonary and extrapulmonary sequestrations, although their relative severity seems unrelated to presenting symptoms.

Utility of Nuclear Grading System in Epithelioid Malignant Pleural Mesothelioma in Biopsy-heavy Setting: An External Validation Study of 563 Cases.

Nuclear grading systems for epithelioid malignant pleural mesothelioma (MPM) have been proposed but it remains uncertain if they could be applied in a biopsy-heavy setting. Using the proposed system, we conducted an independent, external validation study using 563 consecutive cases of epithelioid MPM diagnosed at our institution between 2003 and 2017, of which 87% of patients underwent biopsies only. The median number of sites sampled was 1, with a median maximum tissue dimension of 17 mm (biopsy) and 150 mm (resection). The median overall survival (OS) was 14.7 months. The frequencies of grade I, II, and III tumors were 31% (132/563), 52% (292/563), and 17% (94/563). Grade I tumors were associated with the most favorable median OS (24.7 mo) followed by grades II (12.7 mo) and III (7.2 mo). The 2-tier nuclear grade separated tumors into low grade (19.3 mo) and high grade (8.9 mo). In multivariate analysis, 3-tier nuclear grade, 2-tier nuclear grade, and mitosis-necrosis score predicted OS independent of age, procedural type, solid-predominant growth pattern, necrosis, and atypical mitosis (all P<0.001 except 2-tier nuclear grade, P=0.001). In the scenario of a single- site biopsy with tissue dimension ≤10 mm, none but age (P=0.002) were independently predictive. Our data also suggested sampling 3 sites or a maximum tissue dimension of at least 20 mm from a single site is optimal for nuclear grade assessment. In conclusion our study confirmed the utility of nuclear grade in epithelioid MPM using a biopsy-heavy cohort provided the tissue sample met minimum dimensional criteria.

Physiological properties of human diaphragm muscle fibres and the effect of chronic obstructive pulmonary disease.

The contractile and actomyosin ATPase properties of single fibres were examined in human diaphragm muscle obtained from patients with and without chronic obstructive pulmonary disease (COPD). Costal diaphragm biopsies were taken from five patients without evidence of COPD and from 11 age-matched individuals with varying degrees of the disease. Our aim was to establish whether changes in contractile properties of COPD diaphragm could be fully explained by the previously documented shift towards a greater proportion of type I myosin heavy chain isoform in COPD. The relative proportion of type I diaphragm fibres from non-COPD and COPD patients was measured by gel electrophoresis, and was negatively correlated with FEV(1) over the full range of values investigated. There was also significant atrophy of the type I fibre population in COPD diaphragms. Isometric tension was similar among the fibre types and between the COPD and non-COPD patients. The intrinsic energetic properties of diaphragm fibres were examined by monitoring the time-resolved actomyosin ATPase activity in COPD and non-COPD fibres that produced similar isometric forces. The isometric ATPase rate in COPD fibres was reduced to 50% of the rate in non-COPD fibres; hence, the cost of isometric contraction in type I and type IIA COPD fibres was reduced to between one-third and one-half of the tension cost calculated for non-COPD fibres. The rate of force development in type I COPD fibres was reduced to 50% of the rate seen in non-COPD type-I fibres. No difference in the rate of ATP consumption between COPD and non-COPD fibres was evident during isovelocity shortening. These data extend previous findings showing that aspects of breathing mechanics during progressive COPD are associated with remodelling of the diaphragm fibre-type distribution; on top of the increase in type I fibres there are fibre-specific reductions in force development rate (type I fibres) and ATPase rate that are consistent with the impairment of cross-bridge cycling kinetics.

Increasing frequency of non-smoking lung cancer: Presentation of patients with early disease to a tertiary institution in the UK.

BACKGROUND: Never-smokers with lung cancer often present late as there are no established aetiological risk factors. The aim of the study is to define the frequency over time and characterise clinical features of never-smokers presenting sufficiently early to determine if it is possible to identify patients at risk. METHODS: We retrospectively analysed data from a prospectively collected database of patients who underwent surgery. The frequency was defined as number of never-smokers versus current and ex-smokers by year. Clinical features at presentation were collated as frequency. RESULTS: A total of 2170 patients underwent resection for lung cancer from March 2008 to November 2014. The annual frequency of developing lung cancer in never-smokers increased from 13% to 28%, attributable to an absolute increase in numbers and not simply a change in the ratio of never-smokers to current and ex-smokers. A total of 436 (20%) patients were never-smokers. The mean age was 60 (16 SD) years and 67% were female. Presenting features were non-specific consisting of cough in 34%, chest infections in 18% and haemoptysis in 11%. A total of 14% were detected on incidental chest film, 30% on computed tomography, 7% on positron-emission tomography/computed tomography and 1% on MRI. CONCLUSIONS: We observed more than a double of the annual frequency of never-smokers in the last 7 years. Patients present with non-specific symptoms and majority were detected on incidental imaging, a modality that is likely to play an increasingly important role for early detection in this cohort that does not have any observable clinical risk factors.

Management of Progressive Pulmonary Nodules Found during and outside of CT Lung Cancer Screening Studies.

Although the effectiveness of screening for lung cancer remains controversial, it is a fact that most lung cancers are diagnosed at an advanced stage outside of lung cancer screening programs. In 2013, the U.S. Preventive Services Task Force revised its lung cancer screening recommendation, now supporting lung cancer screening by low-dose computed tomography in patients at high risk. This is also endorsed by many major medical societies and advocacy group stakeholders, albeit with different eligibility criteria. In Europe, population-based lung cancer screening has so far not been recommended or implemented, as some important issues remain unresolved. Among them is the open question of how enlarging pulmonary nodules detected in lung cancer screening should be managed. This article comprises two parts: a review of the current lung cancer screening approaches and the potential therapeutic options for enlarging pulmonary nodules, followed by a meeting report including consensus statements of an interdisciplinary expert panel that discussed the potential of the different therapeutic options.

Passive properties of the diaphragm in COPD.

Structural adaptations that occur in the diaphragm muscle of patients with chronic obstructive pulmonary disease (COPD), namely an increase in type I fibers and a decrease in type II fibers, have been explored in terms of the active contractile properties of the diaphragm. The aim of this study was to test the passive properties of the diaphragm by measuring the force response of relaxed diaphragm muscle fibers to stretching to determine the effect of COPD on these properties. Costal diaphragm biopsies were taken from patients with COPD and from controls with normal pulmonary function. From these biopsies, titin expression was assessed in diaphragm homogenates by gel electrophoresis, and the restoring force was measured by incremental stretching of single fibers in the relaxed state and measuring the force response to stretching. A quadratic model was used to illustrate the relationship between restoring force and muscle fiber length, and it revealed that COPD fibers generate significantly lower restoring forces than control fibers as judged by the area under the force-length curve. Furthermore, this finding applies to both type I and type II fibers. Gel electrophoresis revealed different titin isoforms in COPD and controls, consistent with the conclusion that COPD results not only in a change in muscle fiber-type distribution but in a structural change in the titin molecule in all muscle fiber types within the diaphragm. This may assist the muscle with the energetic changes in the length of the diaphragm required during breathing in COPD.

Nuss procedure improves the quality of life in young male adults with pectus excavatum deformity.

OBJECTIVE: The Nuss procedure is a minimally invasive pectus repair. This study represents an attempt towards exploring the changes in quality of life and overall satisfaction in young male adults who underwent a Nuss procedure. METHODS: We have included 20 male patients with a median age of 18 years (range: 14-37 years). We have used two specific questionnaires: the two-step Nuss evaluation Questionnaire modified for Adults (NQ-mA) and a new Single Step Questionnaire (SSQ). The data was analysed using Wilcoxon signed rank test to determine statistical significance of differences, with a <0.05 level of significance. Spearman's correlation coefficient was used to assess the correlation between the answers. RESULTS: The primary indication for surgery was cosmetic. Both questionnaires were adequate to measure disease-specific quality-of-life changes after surgery and were able to confirm the positive impact of surgery on both the physical and the physiological well-being of young adults. Statistical analysis of the scoring of the individual questions and the total score of individual patients revealed a statistically significant improvement (p<0.05) following surgery. The SSQ had a highly significant correlation to the NQ-mA questionnaire (correlation coefficient=0.682, p=0.001). Overall, the SSQ revealed a statistically significant improvement (p=0.001) in self-esteem and a high level of satisfaction following the Nuss procedure. Only two patients fell into a low satisfaction group. CONCLUSION: The Nuss procedure has already been shown to have a positive impact on both the physical and psychosocial well-being of children who are suffering from pectus excavatum deformity. We have shown a similar positive impact in young male adults, in the short term.

Selection for adjuvant chemotherapy in completely resected stage I non-small cell lung cancer: external validation of a Chinese prognostic risk model.

BACKGROUND: The ability to sub-stratify survival within stage I is an important consideration as it is assumed that survival is heterogeneous within this sub-group. Liang et al. recently published a nomogram to predict post-operative survival in patients undergoing lung cancer surgery. The aim of our study is external validation of their published nomogram in a British cohort focusing on stages IA and IB to determine applicability in selection of adjuvant chemotherapy within stage I. METHODS: Patient variables were extracted and the score individually calculated. Receiver operative characteristics curve (ROC) was calculated and compared with the original derivation cohort and the discriminatory ability was further quantified using survival plots by splitting our (external) validation cohort into three tertiles and Kaplan Meier plots were constructed and individual curves tested using Cox regression analysis on Stata 13 and R 3.1.2 respectively. RESULTS: A total of 1,238 patients were included for analysis. For all patients from stage IA to IIB the mean (SD) score was 9.95 (4.2). The ROC score comparing patients who died versus those that remained alive was 0.62 (95% CI: 0.58 to 0.67). When divided into prognostic score tertiles, survival discrimination remained evident for the entire cohort, as well as those for stage IA and IB alone. The P value comparing survival between the middle and highest score with baseline (low score) was P=0.031 and P=0.034 respectively. CONCLUSIONS: Our results of external validation suggested lower survival discrimination than reported by the original group; however discrimination between survival remained evident for stage I.

Factor XII auto-antibodies present in a patient with a B-cell lymphoma.

A 64-year-old woman was transferred for investigation of a mediastinal mass, biopsy of which showed a diffuse large B-cell lymphoma. She was also found to have an antiphospholipid antibody. The pre-operative coagulation screen showed a prolonged activated partial thromboplastin time, 71.3 s (normal range, 26-36 s), which was not corrected by the addition of normal plasma. The dilute Russell's viper venom time was positive. Anti-cardiolipin assay was strongly positive, immunoglobulin M was 153 AU; immunoglobulin G was normal, 3.1 AU. Assays of factors VIII, IX and XI showed higher concentrations with increasing dilutions in one-stage factor assays from 1: 10 to 1: 80 suggestive of an inhibitor. Factor XII was 9 U/dl and results were unaffected by increasing dilution, suggesting specific antibodies to factor XII. The factor XII antigen was 40 U/dl. The patient had immunoglobulin M auto-antibodies to factor XII.