Kostas Papagiannopoulos

Using next-generation sequencing for high resolution multiplex analysis of copy number variation from nanogram quantities of DNA from formalin-fixed paraffin-embedded specimens

The use of next-generation sequencing technologies to produce genomic copy number data has recently been described. Most approaches, however, reply on optimal starting DNA, and are therefore unsuitable for the analysis of formalin-fixed paraffin-embedded (FFPE) samples, which largely precludes the analysis of many tumour series. We have sought to challenge the limits of this technique with regards to quality and quantity of starting material and the depth of sequencing required. We confirm that the technique can be used to interrogate DNA from cell lines, fresh frozen material and FFPE samples to assess copy number variation. We show that as little as 5 ng of DNA is needed to generate a copy number karyogram, and follow this up with data from a series of FFPE biopsies and surgical samples. We have used various levels of sample multiplexing to demonstrate the adjustable resolution of the methodology, depending on the number of samples and available resources. We also demonstrate reproducibility by use of replicate samples and comparison with microarray-based comparative genomic hybridization (aCGH) and digital PCR. This technique can be valuable in both the analysis of routine diagnostic samples and in examining large repositories of fixed archival material.

Multicenter international randomized comparison of objective and subjective outcomes between electronic and traditional chest drainage systems.

BACKGROUND The aim of this study was to assess the impact of digital versus traditional drainage devices on chest tube removal and patient satisfaction. METHODS A randomized trial of digital versus traditional devices after lobectomy/segmentectomy was conducted at 4 international centers (United Kingdom, Europe, Asia, United States). Patients were managed with overnight suction followed by gravity drainage. Chest tubes were removed when an air leak was not evident anymore and the drained fluid was less than 400 mL/d. RESULTS The groups (digital, 191 patients; traditional, 190 patients) were well matched for baseline and surgical characteristics. There were 325 lobectomies/bilobectomies and 56 segmentectomies, 308 of which were performed by video-assisted thoracic surgery (VATS). Patients randomized to digital systems had a significantly shorter air leak duration (1.0 versus 2.2 days; p=0.001), duration of chest tube placement (3.6 versus 4.7 days; p=0.0001), and postoperative length of stay (4.6 versus 5.6 days; p<0.0001). Subjective end points revealed a perceived improved ability to arise from bed (p=0.008), system convenience for patients and personnel (p=0.02), and the potential for being comfortable when discharged home with the device (p=0.06). A mean difference of 2.6 days from air leak cessation to tube removal was observed, which was similar in the 2 groups (p=0.7). Multivariable regression analysis showed that duration of chest tube placement after air leak cessation was directly associated with the amount of fluid drained during the first 48 hours (p=0.01) and the duration of air leak (p=0.008), independent of hospital location. CONCLUSIONS Patients managed with digital drainage systems experienced a shorter duration of chest tube placement, shorter hospital stays, and higher satisfaction scores compared with those managed with traditional devices. ( CLINICAL TRIAL REGISTRATION NUMBER NCT01747889.).

Video-assisted mediastinoscopy (VAM) for surgical resection of ectopic parathyroid adenoma

BackgroundEctopic mediastinal parathyroid adenomas or hyperplasia account for up to 25% of primary hyperparathyroidism (HPT). Two percent of them are not accessible by standard cervical surgical approaches. Surgical resection has traditionally been performed via median sternotomy or thoracotomy and more recently, via video assisted thoracoscopic surgery (VATS). We present our experience with the novel use of Video-Assisted Mediastinoscopy (VAM) for resection of ectopic mediastinal parathyroid glands.Case presentation4 patients underwent VAM for removal of an ectopic intramediastinal parathyroid gland. All of them had at least one previous unsuccessful neck exploration.In all cases histology confirmed complete resection of ectopic parathyroid glands (3 parathyroid adenomas and one parathyroid hyperplasia). Two of the patients required a partial sternal split to facilitate exploration.ConclusionThe cervical approach for resection of ectopic parathyroid adenomas is frequently unsuccessful. Previously, the standard surgical approach in such cases was sternotomy and exploration of the mediastinum. Recently, a number of less invasive modalities have been introduced.We found that VAM has several advantages. It has a short theatre time does not require a complex anaesthetic and is performed with the patient in classic supine position utilising often a previous cervical scar with good cosmetic results. It offers a short hospital stay; it is cost effective with minimal use of fancy and pricy consumables with a comfortable incision and no violation of the pleural space.Additionally the use of digital Video imaging has increased the sensitivity of the mediastinoscopy and has added safety and confidence in performing a detailed mediastinal exploration with an additional great training value as well.

VATS anatomic lung resections—the European experience

Video-assisted thoracoscopic surgery (VATS) has undergone significant evolution over several decades. Although endoscopic instruments continued to improve, it was not until 1992 that the first VATS lobectomy for lung cancer was performed. Despite significant seeding of such procedure in several thoracic units globally, the uptake was slow and frustrating. Many surgeons considered it complex and unsafe being skeptic about its oncological validity. The last decade has witnessed significant change of practice in many thoracic units with a new generation of VATS thoracic surgeons. Additionally the technique has been refined, standardized and proved its validity and superiority in lung cancer treatment.

A computational index derived from whole-genome copy number analysis is a novel tool for prognosis in early stage lung squamous cell carcinoma.

Squamous cell carcinoma of the lung is remarkable for the extent to which the same chromosomal abnormalities are detected in individual tumours. We have used next generation sequencing at low coverage to produce high resolution copy number karyograms of a series of 89 non-small cell lung tumours specifically of the squamous cell subtype. Because this methodology is able to create karyograms from formalin-fixed paraffin-embedded material, we were able to use archival stored samples for which survival data were available and correlate frequently occurring copy number changes with disease outcome. No single region of genomic change showed significant correlation with survival. However, adopting a whole-genome approach, we devised an algorithm that relates to total genomic damage, specifically the relative ratios of copy number states across the genome. This algorithm generated a novel index, which is an independent prognostic indicator in early stage squamous cell carcinoma of the lung.

Current practices in the management of malignant pleural effusions: a survey among members of the European Society of Thoracic Surgeons

Objectives Malignant pleural effusion (MPE) commonly complicates advanced malignancy and their exact management is still undefined. We undertook a survey to determine the current practice among members of the European Society of Thoracic Surgeons (ESTS). Methods A cross-sectional survey focused on the current practice of management of MPE was developed by the authors. The questions were outlined after a review of the literature and circulated in an Internet-based survey format. Results Computed tomography (125, 92%) and chest X-ray (106, 78%) are the most common imaging modalities performed in the initial evaluation. Video-assisted thoracoscopic surgery for washout and pleurodesis (93, 68%) was reported as the preferred approach to patients with uncomplicated MPE. Sixty-one (45%) of the responding colleagues routinely use large bore chest tubes for draining malignant effusions. Forty-nine (35%) surgeons would not apply suction to the drainage system, whilst 50 (37%) would use -2 kPa or less. Talc (124, 91%) is the most commonly used sclerosing agent for pleurodesis in the context of malignant pleural effusion. The practice of 76 (56%) of the respondents is not informed by any clinical guidelines, whilst 60 (44%) reported adhering to the 2010 British Thoracic Society Pleural Disease Guideline. Seventy-one (52%) declared that the guidance was in need of updating or revision. Conclusions This survey demonstrates the lacking adoption of the existing clinical guidance in this field, as well as the need for more contemporary guidelines for a better-informed practice. The ESTS Working Group on the management of MPE has been established for this purpose.

A risk-adjusted financial model to estimate the cost of a video-assisted thoracoscopic surgery lobectomy programme.

OBJECTIVE To develop a clinically risk-adjusted financial model to estimate the cost associated with a video-assisted thoracoscopic surgery (VATS) lobectomy programme. METHODS Prospectively collected data of 236 VATS lobectomy patients (August 2012-December 2013) were analysed retrospectively. Fixed and variable intraoperative and postoperative costs were retrieved from the Hospital Accounting Department. Baseline and surgical variables were tested for a possible association with total cost using a multivariable linear regression and bootstrap analyses. Costs were calculated in GBP and expressed in Euros (EUR:GBP exchange rate 1.4). RESULTS The average total cost of a VATS lobectomy was €11 368 (range €6992-€62 535). Average intraoperative (including surgical and anaesthetic time, overhead, disposable materials) and postoperative costs [including ward stay, high dependency unit (HDU) or intensive care unit (ICU) and variable costs associated with management of complications] were €8226 (range €5656-€13 296) and €3029 (range €529-€51 970), respectively. The following variables remained reliably associated with total costs after linear regression analysis and bootstrap: carbon monoxide lung diffusion capacity (DLCO) <60% predicted value (P = 0.02, bootstrap 63%) and chronic obstructive pulmonary disease (COPD; P = 0.035, bootstrap 57%). The following model was developed to estimate the total costs: 10 523 + 1894 × COPD + 2376 × DLCO < 60%. The comparison between predicted and observed costs was repeated in 1000 bootstrapped samples to verify the stability of the model. The two values were not different (P > 0.05) in 86% of the samples. A hypothetical patient with COPD and DLCO less than 60% would cost €4270 more than a patient without COPD and with higher DLCO values (€14 793 vs €10 523). CONCLUSIONS Risk-adjusting financial data can help estimate the total cost associated with VATS lobectomy based on clinical factors. This model can be used to audit the internal financial performance of a VATS lobectomy programme for budgeting, planning and for appropriate bundled payment reimbursements.

Pleural myxoid liposarcoma: features of 2 cases and associated literature review

Primary pleural myxoid liposarcoma is a rare entity and no agreed treatment options have been formulated once diagnosis has been made. We report two cases with subsequent management and make recommendations for treatment pathways in these rare cases.

Multicentric evaluation of the impact of central tumour location when comparing rates of N1 upstaging in patients undergoing video-assisted and open surgery for clinical Stage I non-small-cell lung cancer

OBJECTIVES Large retrospective series have indicated lower rates of cN0 to pN1 nodal upstaging after video-assisted thoracic surgery (VATS) compared with open resections for Stage I non-small-cell lung cancer (NSCLC). The objective of our multicentre study was to investigate whether the presumed lower rate of N1 upstaging after VATS disappears after correction for central tumour location in a multivariable analysis. METHODS Consecutive patients operated for PET-CT based clinical Stage I NSCLC were selected from prospectively managed surgical databases in 11 European centres. Central tumour location was defined as contact with bronchovascular structures on computer tomography and/or visibility on standard bronchoscopy. RESULTS Eight hundred and ninety-five patients underwent pulmonary resection by VATS (n = 699, 9% conversions) or an open technique (n = 196) in 2014. Incidence of nodal pN1 and pN2 upstaging was 8% and 7% after VATS and 15% and 6% after open surgery, respectively. pN1 was found in 27% of patients with central tumours. Less central tumours were operated on by VATS compared with the open technique (12% vs 28%, P < 0.001). Logistic regression analysis showed that only tumour location had a significant impact on N1 upstaging (OR 6.2, confidence interval 3.6-10.8; P < 0.001) and that the effect of surgical technique (VATS versus open surgery) was no longer significant when accounting for tumour location. CONCLUSIONS A quarter of patients with central clinical Stage I NSCLC was upstaged to pN1 at resection. Central tumour location was the only independent factor associated with N1 upstaging, undermining the evidence for lower N1 upstaging after VATS resections. Studies investigating N1 upstaging after VATS compared with open surgery should be interpreted with caution due to possible selection bias, i.e. relatively more central tumours in the open group with a higher chance of N1 upstaging.

Outcome after video-assisted thoracoscopic surgery and open pulmonary lobectomy in patients with low VO2 max: a case-matched analysis from the ESTS database

OBJECTIVES The aim was to verify the association of low VO2 max with postoperative morbidity and mortality after video-assisted thoracoscopic surgery (VATS) or open pulmonary lobectomy using the European Society of Thoracic Surgeons (ESTS) database. METHODS A retrospective analysis of data collected from the ESTS database was conducted. A total of 1684 lobectomy patients with available VO2 max values were included (2007-14). Patients operated through VATS (281 patients) or thoracotomy (1403 patients) were separately analysed. Propensity score analyses were performed to match patients with high (≥15 ml/kg/min) and low VO2 max (<15 ml/kg/min) for each approach. The following variables were used to construct the score: age, body mass index, predicted postoperative forced expiratory volume in 1 s (%), coronary artery disease, American Society of Anaesthesiology grade and Eastern Cooperative Oncology Group performance score. Cardiopulmonary morbidity and 30-day mortality were compared between the matched groups. RESULTS Mean VO2 max was 17.4 ml/kg/min. A total of 471 patients (28%) had low VO2 max. Overall postoperative cardiopulmonary morbidity and mortality rates were 30% (505 patients) and 4.1% (70 patients), respectively. Morbidity and mortality rates in low VO2 max patients were 33% (156 patients) and 6% (28 patients), respectively. After VATS, cardiopulmonary morbidity and mortality rates were 2-fold (13 of 72, 18% vs 143 of 399, 36%, P = 0.003) and 5-fold (1 of 72, 1.4% vs 27 of 399, 6.7%, P = 0.09) lower compared with thoracotomy. Matched comparison after thoracotomy (399 pairs): Mortality was significantly higher in patients with low VO2 max (27 patients, 6.7%) compared with those with high VO2 max (11 patients, 2.8%, P = 0.008). Complication rates were similar between the two groups (low VO2 max: 143 patients, 36% vs high VO2 max: 133 patients, 33%, respectively, P = 0.5). Matched comparison after vats (72 pairs): Morbidity and mortality rates of patients with low VO2 max were similar to those of patients with high VO2 max (morbidity: 13 patients, 18% vs 17 patients, 24%, P = 0.4; mortality: 1 patient, 1.4% vs 4 patients, 5.5%, P = 0.4). CONCLUSIONS Low VO2 max was not associated with an increased surgical risk after VAT lobectomy, which challenges the traditional operability criteria when this technique is used.