Is elective cancer surgery feasible during the lock-down period of the COVID-19 pandemic? Analysis of a single institutional experience of 404 consecutive patients.

BACKGROUND: We aimed to assess the feasibility and short-term clinical outcomes of surgical procedures for cancer at an institution using a coronavirus disease 2019 (COVID-19)-free surgical pathway during the peak phase of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. MATERIALS AND METHODS: This was a single-center study, including cancer patients from all surgical departments, who underwent elective surgical procedures during the first peak phase between March 10 and June 30, 2020. The primary outcomes were the rate of postoperative SARS-CoV-2 infection and 30-day pulmonary or non-pulmonary related morbidity and mortality associated with SARS-CoV-2 disease. RESULTS: Four hundred and four cancer patients fulfilling inclusion criteria were analyzed. The rate of patients who underwent open and minimally invasive procedures was 61.9% and 38.1%, respectively. Only one (0.2%) patient died during the study period due to postoperative SARS-CoV2 infection because of acute respiratory distress syndrome. The overall non-SARS-CoV2 related 30-day morbidity and mortality rates were 19.3% and 1.7%, respectively; whereas the overall SARS-CoV2 related 30-day morbidity and mortality rates were 0.2% and 0.2%, respectively. CONCLUSIONS: Under strict institutional policies and measures to establish a COVID-19-free surgical pathway, elective and emergency cancer operations can be performed with acceptable perioperative and postoperative morbidity and mortality.

Elevation in serum uric acid levels predicts favourable response to erlotinib treatment in patients with metastatic non-small-cell lung cancer.

WHAT IS KNOWN AND OBJECTIVE: Erlotinib is a small molecule tyrosine kinase inhibitor which blocks the activation of epidermal growth factor receptor (EGFR), a transmembrane receptor that is upregulated in many cancer types. Inhibition of angiogenesis with consequent impairments in intratumoral microcirculation is one of the mechanisms through which EGFR inhibition halts the progression of cancer. A consequence of impaired microcirculation is intratumoral hypoxia, which results in increases in serum uric acid levels. The goal of this study was to investigate the relationship between serum uric acid levels and response to erlotinib in metastatic non-small-cell lung cancer (NSCLC). METHODS: A total of 56 patients with metastatic non-small-cell lung cancer who received erlotinib for a duration of at least 3 months were included in this retrospective cohort study. Demographic characteristics, progression status, baseline serum uric levels and 3-month serum uric acid levels were recorded and analysed. RESULTS AND DISCUSSION: Of the study population, 21 (37.5%) were female and 35 (62.5%) were male patients. No significant difference in above demographic characteristics was observed among exitus, survivor with progression and survivor without progression groups. Patients who responded favourably to erlotinib with no progression of their disease had significantly increased uric acid levels at 3-month follow-up (P = .01). Such a correlation was not observed if the patient was exitus (P = .47) or had progressed on erlotinib therapy (P = .19). WHAT IS NEW AND CONCLUSION: In conclusion, this study is the first to demonstrate significant increases in serum uric acid levels in patients with metastatic NSCLC who responded favourably to erlotinib and had no progression under erlotinib therapy. Further studies are required to confirm and characterize serum uric acid as a novel biomarker in predicting the outcome in those with metastatic NSCLC.

Hyperthermic intraperitonal chemotherapy is an independent risk factor for development of acute kidney injury.

PURPOSE: Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) or hyperthermic intrapleural chemotherapy (HIC) has been established as the new treatment modality for selected patients with peritoneal and pleural malignancies. The purpose of the study was to compare the development of acute kidney injury (AKI) in patients who received intravenous cisplatin alone, HIPEC and underwent surgery. METHODS: This retrospective study included 104 patients who underwent different therapeutic procedures including systemic cisplatin, surgery and HIPEC or HIC using cisplatin for the treatment of peritoneal carcinomatosis from a variety of primary tumors at Koc University Hospital and American Hospital between January 2015 to December 2017. RESULTS: AKI developed in 18 (17.3%) patients. Baseline creatinine was significantly increased in 3 groups after therapies. The development of AKI was highest in patients treated with HIPEC compared to patients treated with intravenous cisplatin and patients who underwent surgery. AKI developed 31.2% in the HIPEC group (10 of 32 patients), 11.7% in the surgery group (4 of 34 patients) and 10.5% in intravenous cisplatin group (4 of 38 patients), respectively (p 0.04). CONCLUSION: HIPEC may not be so safe with regard to kidney function. Every attempt should be taken to decrease kidney damage during this procedure.

A case of uncontrolled severe asthma patient with coexisting carcinoid tumor presenting as pneumomediastinum.

INTRODUCTION: Patients with inadequately controlled or uncontrolled asthma are at a greater risk of attacks for asthma requiring emergency room visits or hospital admissions. There is a significant correlation between the severity of the disease and the severity of exacerbations. Patients with poorly controlled asthma are at a higher risk for complications. CASE STUDY: We present a 24-year-old aspirin-intolerant, uncontrolled asthma patient with the complication of pneumomediastinum. RESULTS: Severe symptoms persisted after the resolution of the pneumomediastinum despite intense anti-inflammatory and anti-obstructive therapy. A bronchoscopy revealed an endobronchial lesion and she was diagnosed with a carcinoid tumor. CONCLUSION: This case is an example of the importance of re-evaluating asthma patients who do not respond to standard medical treatment. Clinicians should be aware of the complications associated with asthma attacks such as pneumomediastinum and the possibility of a differential diagnosis that worsen asthma symptoms such as a carcinoid tumor.

Factors associated with pulmonary recurrence after pulmonary metastasectomy for sarcomatous disease.

PURPOSE: To analyze the factors associated with survival and pulmonary recurrence after complete metastasectomy for patients with sarcomatous disease. METHODS: Among the 51 patients who underwent complete pulmonary metastasectomy at our hospital between January 2002 and November 2010, 30 (58.8 %) suffered pulmonary recurrence in an ipsilateral hemithorax. We analyzed the factors affecting survival and recurrence after complete metastasectomy. RESULTS: The 51 patients who underwent pulmonary metastasectomy comprised 33 male and 18 female patients, with a median age of 22 years (range 11-61 years). The median survival was 24 months. Multivariate analysis revealed recurrence (p = 0.016) and the type of tumor (p = 0.024) as independent predictors of survival. Recurrence developed in 30 (58.8 %) patients. The risk of recurrence was higher in patients with a DFI <12 months and >1 metastasis resected during the initial metastasectomy. CONCLUSIONS: Based on the findings of our analysis, patients with a DFI <12 months and >1 metastases resected during initial surgery have a higher risk of recurrence. We recommend postoperative follow-up at frequent intervals and reconsideration of oncological treatment after complete resection.

The Practice of Antimicrobial Stewardship in Thoracic Surgery and its Effectiveness.

This study examines the effects of the bundle of antimicrobial stewardship measures for prophylactic antibiotics among thoracic surgery patients. A local protocol, based on current guidelines starting from December 2014, was developed by the Infection Control and Thoracic Surgery Teams. The effects of this protocol were assessed by monitoring a total of 1380 patients before and after its implementation from January 1, 2011, to December 31, 2022.

Extracellular Matrix Sulfation in the Tumor Microenvironment Stimulates Cancer Stemness and Invasiveness.

Tumor extracellular matrices (ECM) exhibit aberrant changes in composition and mechanics compared to normal tissues. Proteoglycans (PG) are vital regulators of cellular signaling in the ECM with the ability to modulate receptor tyrosine kinase (RTK) activation via their sulfated glycosaminoglycan (sGAG) side chains. However, their role on tumor cell behavior is controversial. Here, it is demonstrated that PGs are heavily expressed in lung adenocarcinoma (LUAD) patients in correlation with invasive phenotype and poor prognosis. A bioengineered human lung tumor model that recapitulates the increase of sGAGs in tumors in an organotypic matrix with independent control of stiffness, viscoelasticity, ligand density, and porosity, is developed. This model reveals that increased sulfation stimulates extensive proliferation, epithelial-mesenchymal transition (EMT), and stemness in cancer cells. The focal adhesion kinase (FAK)-phosphatidylinositol 3-kinase (PI3K) signaling axis is identified as a mediator of sulfation-induced molecular changes in cells upon activation of a distinct set of RTKs within tumor-mimetic hydrogels. The study shows that the transcriptomic landscape of tumor cells in response to increased sulfation resembles native PG-rich patient tumors by employing integrative omics and network modeling approaches.

Scrape cytology and radiological solid size correlation can be used in the intraoperative management of subsolid lung nodules.

BACKGROUND: The term radiologic subsolid lung nodule (SLN) represents a heterogeneous group of non-neoplastic and neoplastic lesions. Intraoperative evaluation (IO) is often required to differentiate and diagnose. The current study aims to investigate the feasibility and reliability of scrape cytology (SC) and radiologic solid size correlation for the IO diagnosis of SLNs. METHODS: Sixty-eight patients with SLN signs were eligible to take part in the study due to intraoperatively prepared SC slides. We managed to complete the blind radiologic solid size measurement and cytologic evaluation retrospectively. Cases were grouped into three categories based on their cytological features: Group-0 (Benign), Group-1 (mild atypical features), and Group-2 (severe atypical features/unequivocally carcinoma). IO diagnoses were given by combining the radiologic solid size and cytological findings. RESULTS: Cytological features of Group-1 were observed in 100%, 93%, 32.5%, and 17% of the AIS, MIA, IA, and benign lesions, respectively. Cytological features of Group-2 were observed in 67.5%, and 7% of the IA and MIA, respectively. By combining cytology with radiologic solid size, 100%, 85%, 71%, and 83% of the AIS, IA, MIA, and benign lesions respectively were diagnosed correctly. Fifteen (15%) percent of the IA cases were underdiagnosed as MIA since their radiological solid sizes were less than 0.5 cm with cytological features of Group-1. Conversely, 29% of the MIA cases were overdiagnosed as IA since their radiological solid sizes were greater than 0.5 cm. CONCLUSION: SLNs should be handled with caution in terms of IO management. SC and radiologic solid size correlation both provide a practical and tissue-protecting approach for the IO evaluation of SLNs, ensuring a high consistency between IO and definitive diagnosis.

Combination of CEACAM5, EpCAM and CK19 gene expressions in mediastinal lymph node micrometastasis is a prognostic factor for non-small cell lung cancer.

BACKGROUND: Lung cancer is known as the most common and highly metastatic form of cancer worldwide. Tumour node metastasis (TNM) staging is the gold standard classification system for the decision-making process for appropriate treatment. Particularly N status has the most important prognostic value in the absence of distant metastasis. Traditional diagnostic methods are capable of detecting metastasis; however, they may fail to detect micrometastasis, which plays a role in disease recurrence and patients' long-term survival. Occult micrometastasis can change the tumour's TNM staging and, consequently, the patient's treatment regimen. METHODS: The median number of three lymph node tissues were collected from 30 patients who underwent surgery for non-small cell lung cancer. Lymph node tissues were collected from different lymph node stations according to the location of the patient's tumour. CK19, EpCAM and CEACAM5 gene expressions were analysed in tissues using quantitative real-time polymerase chain reaction to detect micrometastasis in distant lymph nodes. RESULTS: Triple positivity was seen in 26 out of 30 patients which 19 patients were upstaged from N0 to N2. While survival was not significantly affected between upstaged and non-upstaged patients, patients upstaged with multiple-station N2 had a significantly higher recurrence and lower survival compared to single-station N2. CONCLUSION: A combination of CK19, EpCAM and CEACAM5 gene expressions in lymph nodes can be used to identify micrometastasis which postoperatively may be used as a tool to predict patients' recurrence and survival.

Different Decellularization Methods in Bovine Lung Tissue Reveals Distinct Biochemical Composition, Stiffness, and Viscoelasticity in Reconstituted Hydrogels.

Extracellular matrix (ECM)-derived hydrogels are in demand for use in lung tissue engineering to mimic the native microenvironment of cells in vitro. Decellularization of native tissues has been pursued for preserving organotypic ECM while eliminating cellular content and reconstitution into scaffolds which allows re-cellularization for modeling homeostasis, regeneration, or diseases. Achieving mechanical stability and understanding the effects of the decellularization process on mechanical parameters of the reconstituted ECM hydrogels present a challenge in the field. Stiffness and viscoelasticity are important characteristics of tissue mechanics that regulate crucial cellular processes and their in vitro representation in engineered models is a current aspiration. The effect of decellularization on viscoelastic properties of resulting ECM hydrogels has not yet been addressed. The aim of this study was to establish bovine lung tissue decellularization for the first time via pursuing four different protocols and characterization of reconstituted decellularized lung ECM hydrogels for biochemical and mechanical properties. Our data reveal that bovine lungs provide a reproducible alternative to human lungs for disease modeling with optimal retention of ECM components upon decellularization. We demonstrate that the decellularization method significantly affects ECM content, stiffness, and viscoelastic properties of resulting hydrogels. Lastly, we examined the impact of these aspects on viability, morphology, and growth of lung cancer cells, healthy bronchial epithelial cells, and patient-derived lung organoids.

KRAS signaling in malignant pleural mesothelioma.

Malignant pleural mesothelioma (MPM) arises from mesothelial cells lining the pleural cavity of asbestos-exposed individuals and rapidly leads to death. MPM harbors loss-of-function mutations in BAP1, NF2, CDKN2A, and TP53, but isolated deletion of these genes alone in mice does not cause MPM and mouse models of the disease are sparse. Here, we show that a proportion of human MPM harbor point mutations, copy number alterations, and overexpression of KRAS with or without TP53 changes. These are likely pathogenic, since ectopic expression of mutant KRASG12D in the pleural mesothelium of conditional mice causes epithelioid MPM and cooperates with TP53 deletion to drive a more aggressive disease form with biphasic features and pleural effusions. Murine MPM cell lines derived from these tumors carry the initiating KRASG12D lesions, secondary Bap1 alterations, and human MPM-like gene expression profiles. Moreover, they are transplantable and actionable by KRAS inhibition. Our results indicate that KRAS alterations alone or in accomplice with TP53 alterations likely play an important and underestimated role in a proportion of patients with MPM, which warrants further exploration.

Pyruvate Dehydrogenase Contributes to Drug Resistance of Lung Cancer Cells Through Epithelial Mesenchymal Transition.

Recently, there has been a growing interest on the role of mitochondria in metastatic cascade. Several reports have shown the preferential utilization of glycolytic pathway instead of mitochondrial respiration for energy production and the pyruvate dehydrogenase (PDH) has been considered to be a contributor to this switch in some cancers. Since epithelial mesenchymal transition (EMT) is proposed to be one of the significant mediators of metastasis, the molecular connections between cancer cell metabolism and EMT may reveal underlying mechanisms and improve our understanding on metastasis. In order to explore a potential role for PDH inhibition on EMT and associated drug resistance, we took both pharmacological and genetic approaches, and selectively inhibited or knocked down PDHA1 by using Cpi613 and shPDHA1, respectively. We found that both approaches triggered morphological changes and characteristics of EMT (increase in mesenchymal markers). This change was accompanied by enhanced wound healing and an increase in migration. Interestingly, cells were more resistant to many of the clinically used chemotherapeutics following PDH inhibition or PDHA1 knockdown. Furthermore, the TGFßRI (known as a major inducer of the EMT) inhibitor (SB-431542) together with the PDHi, was effective in reversing EMT. In conclusion, interfering with PDH induced EMT, and more importantly resulted in chemoresistance. Therefore, our study demonstrates the need for careful consideration of PDH-targeting approaches in cancer treatment.

Immune profiling after minimally invasive lobectomy.

OBJECTIVES: Whether acute phase and immune responses are minimally affected following minimally invasive lung surgery needs further investigation. We performed a pilot study to evaluate the immune profile of patients who underwent video-assisted thoracoscopic surgery or robot-assisted thoracic surgery lobectomies for the treatment of suspicious or known stage I non-small-cell lung cancer. METHODS: Blood samples were taken preoperatively and 3 and 24 h postoperatively were analysed for C-reactive protein, glucose, cortisol, tumour necrosis factor alpha (TNF-α), interleukin 8 (IL-8) and interleukin 10 (IL-10) levels. TNF-α, IL-8 and IL-10 were also measured in lung tissues. T (CD4, CD8), B (CD19) and natural killer (CD56, CD16) cell counts and natural killer cell functions were analysed using a flow cytometry-based assay before and after surgery. RESULTS: Minimally invasive surgery (robot-assisted thoracic surgery + video-assisted thoracoscopic surgery) significantly decreased IL-10 (P = 0.016) levels after surgery. No significant differences were detected in TNF-α (P = 0.48) and IL-8 (P = 0.15) levels before and after surgery. C-reactive protein (P < 0.001), cortisol (P < 0.001) and glucose levels (P < 0.001) increased significantly after surgery. Lymphocyte, total T cell, CD3+CD4+ and CD3+CD8+ CD16+CD56+ cell counts were significantly lower on postoperative day 1. CONCLUSION: There seems to be a dynamic balance between pro- and anti-inflammatory cytokines and immune cells following minimally invasive lobectomy.

The prediction of spread through air spaces with preoperative 18F-FDG PET/CT in cases with primary lung adenocarcinoma, its effect on the decision for an adjuvant treatment and its prognostic role.

PURPOSE: In lung adenocarcinoma cases, 'spread through air spaces' (STAS) is a new indicator of invasion and directly related to disease survival. The aim of our study is to establish whether a preoperatively performed 18F-Fluorodeoxyglucose (FDG) PET/computed tomography (CT) imaging data can predict the presence of STAS in cases with lung adenocarcinoma and thus predict the decision for the type of surgery and adjuvant chemotherapy. MATERIALS AND METHODS: Between 2000 and 2019, we retrospectively analyzed 63 patients with lung adenocarcinoma cases that had undergone lobectomy or pneumonectomy. Semiquantitative parameters were calculated and metabolic tumor volume (MTV)/CT volume (CTV) ratio was recorded from FDG PET/CT data. The pathological samples from these patients were evaluated for STAS. All these values were evaluated for their correlation with the alveolar spread. RESULTS: There was no statistically significant correlation to be found between CTV, MTV, total lesion glycolysis (TLG), standardized uptake value (SUV)max, SUVmean and STAS (P > 0.05). However, MTV/CTV ratio above 1 had statistically more alveolar spread. In the group with an MTV ratio above 1, STAS positivity was 27 (75%), and 9 (25%) did not have STAS, whereas these were 6 (22.2%) patients who had STAS, and 21 (77.8%) did not have STAS in the group with below 1 (P < 0.001). CONCLUSIONS: In the preoperative PET study inoperable lung adenocarcinoma cases, MTV/CTV ratio higher than 1 was found to predict STAS positivity. As a result, it was found that it provided significant clinical additional information regarding the need for a surgical approach (lobar resection instead of sublobar) and adjuvant chemotherapy.

Concomittant occurence of well-differentiated thyroid carcinoma metastasis and chronic lymphocytic leukemia in the same lymph node along with internal jugular vein thrombus: a case report.

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is the most common adult leukemia. The coexistence of CLL and papillary thyroid carcinoma (PTC) is extremely rare. PTC sometimes shows microscopic vascular invasion but rarely cause a tumor thrombus in the internal jugular vein (IJV). It is also rare to find both differentiated and poorly differentiated types of thyroid cancer in the same metastatic location. We report a case of 63-year-old Turkish man with history of CLL who had CLL/SLL involvement and PTC metastasis in the same lymph node. Additionally, there was macroscopic metastasis to the IJV with poorly differentiated areas in the removed tumor thrombus. Patient was treated with total thyroidectomy, left radical neck dissection, resection of the left IJV segment that contained the tumor thrombus and radioactive iodine (RAI) therapy. Furthermore, metastatic lesions were found in the brain, lung and bone. Radiotherapy and chemotherapy were performed. However, our patient died approximately 12 months after thyroidectomy. To our knowledge, our present report is the first description with its current features.

The role of adjuvant chemotherapy in resected stage I non - small cell lung cancer: A Turkish Oncology Group Study.

PURPOSE: The benefit of adjuvant chemotherapy for tumors smaller than 4 cm is not clear. We aimed to evaluate the prognostic impact of adjuvant platin-based chemotherapy in high-risk stage I patients with non-small cell lung cancer (NSCLC). METHODS: This cooperative group study included 232 NSCLC patients who underwent curative surgery for stage I disease with tumor size 2-4 cm. Re ults: Median age at presentation was 63 years (range 18-90). The mean tumor size was 29.6 ± 7.3 mm. The frequency of patients with specified risk factors were: visceral pleural effusion (VPI): n: 82 (36.6%); lymphovascular invasion (LVI): n: 86 (39.1%); Grade 3: n: 48 (32.7%); Solid micropapillary pattern (SMP): n: 70 (48.3%). Adjuvant platin-based chemotherapy was administered to 51 patients. During a median follow-up period of 50.5 months 68 patients (29.3%) developed recurrence, 54 (23.3%) died from any cause and 38 (16.4%) of them died of lung cancer. Patients who received chemotherapy compared with the non-chemotherapy group had a longer 5-years relapse-free survival (RFS) (84.5 vs 61.1%). Also on multivariate analysis, adjuvant chemotherapy was a significant independent prognostic factor for RFS. CONCLUSION: Adjuvant platin-based chemotherapy should be considered for patients with small tumors with adverse risk factors. Key words: adjuvant chemotherapy, lung cancer, oncology, lymphovascular invasion, solid-micropapillary pattern, platinum-based therapy.

Extended resection: is it feasible for pulmonary metastases?

BACKGROUND: Extended resections may be necessary to achieve tumor-free borders for secondary pulmonary malignancies. This study was performed to analyze the outcomes that result from extended resections of pulmonary metastases. METHODS: Between February 1991 and December 2008, a total of 25 extended pulmonary resections (resection of the chest wall and diaphragm, vascular procedures, sleeve resections, pneumonectomies, atrial resections, and completion pneumonectomies) were performed on 250 patients undergoing 319 metastasectomy procedures. The extended resection group was analyzed in terms of disease-free interval, type of resection, operative morbidity, mortality, and survival and was then compared with patients who underwent lobar or sublobar resections. RESULTS: The extended resection group consisted of 14 male and 11 female patients. The mean disease-free interval was 36.02 (minimum 6, maximum 132) months. The extended resection rate was 10%. After 30 days, all patients were alive. For all extended metastasectomy groups, actuarial 5-year survival rates from the time of the extended metastasectomy were 16.3%. Mean survival times of patients who underwent extended resection and lobar or sublobar resection were 40 months (SD = 11) (95% confidence interval, 19-61) and 20 months (SD = 3) (95% confidence interval, 14-26), respectively. This difference was not statistically significant (P = 0.09) (Fig. 2). In the subgroup analysis, survival in the extended resections and lobar or sublobar resections groups was not statistically significant (osteosarcoma, P = 0.758; epithelial tumor, P = 0.11). CONCLUSIONS: Extended resections, which can be performed during pulmonary metastasectomies of patients with tumor-free surgical borders, may establish curative benefits, with low rates of mortality and morbidity.

Level of pleural invasion effects on prognosis in lung cancer.

OBJECTIVE: To analyze the extent of visceral pleural invasion (VPI) and its effect on survival along with its place in determining the T descriptor in TNM staging in our patients. METHODS: A total of 233 patients underwent lung resection. The data were retrospectively analyzed in terms of sex, age, histopathologic type, stage of the tumor, extent of VPI, and survival. Patients who had neoadjuvant chemotherapy or chemoradiotherapy, distant metastasis, parietal pleural invasion, and operative mortality were excluded. RESULTS: The median follow-up was 59 months (range 4-126). The extent of VPI was PL0 in 119 (65.7%) patients, PL1 in 47 (26%) patients, and PL2 in 15 (8%) patients. The median survival rates were 65 (range 43-96) months for PL0, 54 (range 37-72) months for PL1, and 39 (range 12-69) months for PL2. The 5-year overall survival rates were 74.7% for PL0, 77.8% for PL1, and 53.3% for PL2. There were statistically significant differences in overall survival among PL0, PL1, and PL2 ( p = 0.03). In subgroup analysis, the difference was insignificant in PL0 vs PL1 ( p = 0.81), but significant in PL0 vs PL2 ( p = 0.02) and PL1 vs PL2 ( p = 0.04) groups. CONCLUSIONS: This study emphasizes that the presence of VPI is related with poor prognosis independent of lymph node positivity, histologic subtypes, and tumor size. As the study shows, PL0 and PL1 have similar survival rates and these two groups may be considered as VPI (-) patients whereas PL2 disease affects survival outcomes.

Videothoracoscopic thymectomy for nonthymomatous myasthenia gravis: results of 90 patients.

BACKGROUND: Videothoracoscopic thymectomy is an alternative surgical procedure for patients with nonthymomatous myasthenia gravis. The aim of this study is to present our experience and to analyze the factors contributing to the operative morbidity. METHODS: Ninety myasthenia gravis patients were operated through right-sided videothoracoscopy from June 2002 to September 2006. Prospective data recording was performed. Surgeon-related conversion to open surgery, length of the operation, chest tube duration time, duration of hospital stay, amount of drainage, pain score, and complications were evaluated. Factors contributing to longer operation time and longer postoperative stay were studied. RESULTS: The mean length of chest tube duration and postoperative hospital stay was 26.7 +/- 18.6 hours and 2.2 days +/- 1.1 days respectively. Visual analogue scale (VAS) values for pain evaluation were 2.0 +/- 1.4. Surgeon-related open conversion occured in two patients (2.2%). Body mass index (BMI) was the sole significant factor for longer operation time. (23.04 +/- 2.93 versus 25.61 +/- 2.70 (p = 0.001). The amount of pyridostigmine was the only significant factor for longer hospital stay (213.3 +/- 101.5 mg versus 270. 0 +/- 122.6 mg (p = 0.044). CONCLUSIONS: This study demonstrates the right-sided videothoracoscopy is a safe procedure. The only contributing factors were: BMI >25.61 for longer operation time, and pyridostigmine level >270 mg for duration of postoperative stay.

Learning curve in videothoracoscopic thymectomy: how many operations and in which situations?

OBJECTIVE: Videothoracoscopic learning curve is known to vary among different surgeons, and may be influenced by patients and various situations. We aimed to analyze the learning curve of a surgeon in videothoracoscopic thymic surgery for myasthenia gravis. METHODS: This is a descriptive single-center study using collected clinical data from 90 patients undergoing videothoracoscopic thymic surgery between June 2002 and September 2006. Cumulative summation (CUSUM) model was used to evaluate the learning curve for videothoracoscopic thymectomy operations. Unsuccessful situations were accepted as longer operation time, surgeon-related open conversions, readmissions and postoperative complications. Factors affecting longer operation time (patients with operation time longer than the average) and longer postoperative stay (patients with postoperative hospital stay longer than average) were analyzed. RESULTS: Body mass index (BMI) was the only predictor of longer operation time (23.04+/-2.93 vs 25.61+/-2.70 (p=0.001) independent samples test). The amount of prescribed pyridostigmine was the only factor for longer hospital stay (213.3+/-101.5 mg vs 270. 0+/-122.6 mg (p=0.044) Mann-Whitney U-test). CUSUM analysis demonstrated a learning curve with success rates of 80%, 90% and 98%, respectively in the first 30 patients, the next 31-60 patients and after 60 patients. Median operative time declined with surgeons' experience (p<0.001). CONCLUSIONS: A chest surgeon can have a high success rate in videothoracoscopic thymectomy (98%) after 60 operations.