A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was how video-assisted thoracoscopic surgery (VATS) compares to median sternotomy in the surgical management of patients with myasthenia gravis (MG)? Overall 74 papers were found using the reported search, of which 15 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results are tabulated. We conclude that VATS produces equivalent postoperative mortality and complete stable remission (CSR) rates, with superior results in terms of hospital stay, operative blood loss and patient satisfaction at the expense of a doubling of operative time. Six studies comparing VATS and transsternal sternotomy in non-thymomatous myasthenia gravis (NTMG) patients found VATS to have lower operative blood loss (73.8±70.7 vs. 155.3±91.7 ml; P<0.05), reduced total hospital stay (5.6±2.2 vs. 8.1±3.0 days; P=0.008), whilst maintaining equivalent remission rates (33 vs. 44.7%; P=0.16) and mass of thymic tissue resection (37 vs. 34 g; P>0.05). One study comparing video-assisted thoracoscopic extended thymectomy to transsternal thymectomy in only thymoma-associated myasthenia gravis (T-MG) patients found equivalent CSR (11.3 vs. 8.7%, P=0.1090) at six-year follow-up. Thymoma recurrence rate (9.64%) was not significantly different (P=0.1523) between the two groups. Eight studies comparing VATS and transsternal approach in mixed T-MG and NTMG patients found a lower hospital stay (1.9±2.6 vs. 4.6±4.2 days, P<0.001), reduced need for postoperative medication (76.5 vs. 35.7%, P=0.022), lower intensive care unit stay (1.5 vs. 3.2 days, P=0.018), greater symptom improvement (100 vs. 77.9%, P=0.019) and better cosmetic satisfaction (100 vs. 83, P=0.042) with VATS. In concordance with NTMG and T-MG alone patient groups, VATS and transsternal methods had equivalent complication rates (23 vs. 19%, P=0.765) with no mortalities in either group. Even though VATS has a longer operative time (268±51 vs. 177±92 min, P<0.05), its improved cosmesis, reduced need for postoperative medication and equivalent disease resolution outcomes make it a preferable surgical option to the transsternal approach.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was which diagnostic modality [computed tomography (CT), positron emission tomography (PET), combination PET/CT and magnetic resonance imaging (MRI)] provides the best diagnostic and staging information in patients with malignant pleural mesothelioma (MPM). Overall, 61 papers were found using the reported search, of which 14 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results are tabulated. We conclude that fluorodeoxyglucose (FDG)-PET is superior to MRI and CT but inferior to PET-CT, in terms of diagnostic specificity, sensitivity and staging of MPM. Four studies reported outcomes using FDG-PET to diagnose MPM. PET diagnosed MPM with high sensitivity (92%) and specificity (87.9%). Mean standardised uptake value (SUV) was higher in malignant than benign disease (4.91 vs. 1.41, P<0.0001). Lymph node metastases were detected with higher accuracy (80% vs. 66.7%) compared to extrathoracic disease. Three studies assessed the utility of PET-CT to diagnose MPM. Mean SUV was higher in malignant than benign disease (6.5 vs. 0.8, P<0.001). MPM was diagnosed with high sensitivity (88.2%), specificity (92.9%) and accuracy (88.9%). PET-CT had low sensitivity for stage N2 (38%) and T4 (67%) disease. CT-guided needle biopsy definitively diagnosed MPM after just one biopsy (100% vs. 9%) much more often than a 'blind' approach. CT had a lower success rate (92% vs. 100%) than thoracoscopic pleural biopsy but was equivalent to MRI in terms of detection of lymph node metastases (P=0.85) and visceral pleural tumour (P=0.64). CT had a lower specificity for stage II (77% vs. 100%, P<0.01) and stage III (75% vs. 100%, P<0.01) disease compared to PET-CT. Overall, the high specificity and sensitivity rates seen with open pleural biopsy make it a superior diagnostic modality to CT, MRI or PET for diagnosing patients with MPM.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether positron emission tomography is useful in the diagnosis and prognosis of malignant pleural mesothelioma (MPM). Altogether 136 papers were found using the reported search, of which 15 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that fluorodeoxyglucose-positron emission tomography (FDG-PET) accurately differentiates benign from malignant pleural disease, helps detect recurrence and provides prognostic information in terms of staging, survival and mortality. Eleven studies evaluated the role of FDG-PET in the diagnosis and prognosis of MPM. Malignant disease had a higher standardised uptake value (SUV) (6.5 ± 3.4 vs. 0.8 ± 0.6; P < 0.001) than benign pleural disease. Shorter median survival (9.7 vs. 21 months; P = 0.02) was associated with high SUV (>10) than low SUV (<10). PET accurately upstaged 13% and downstaged 27% of cases initially staged with computed tomography (CT). In patients undergoing chemotherapy, higher total glycolytic volume led to a lower median survival (4.9 vs. 11.5 months; P = 0.09), while a decline in FDG uptake was associated with a longer time to tumour progression (14 vs. 7 months; P = 0.02). Four studies observed the role of FDG-PET-CT in the diagnosis and prognosis of MPM. SUV was found to be higher in MPM compared to benign pleural disease (6.5 vs. 0.8; P < 0.001). A higher SUV(max) was observed in primary pleural lesions of metastatic (7.1 vs. 4.7; P = 0.003) compared to non-metastatic disease. Patients who underwent surgery had equivalent survival to those excluded based on scan results (20 vs. 12 months; P = 0.3813). One study compared the utility of PET and PET-CT in the diagnosis and prognosis of mesothelioma. PET-CT was found to be more accurate than PET in terms of staging (P < 0.05) disease. Overall, PET accurately diagnoses MPM, predicts survival and disease recurrence. It can guide further management by predicting the response to chemotherapy and excluding surgery in patients with extrathoracic disease. Combined PET-CT has additional benefits in accurately staging disease.