Prognostic factors for survival in advanced thymomas: The role of the number of involved structures.

BACKGROUND AND OBJECTIVES: The Masoka-Koga and tumor node metastases staging systems for thymoma are based on structures involved, but the prognostic role of the number of infiltrated/involved structures is still debated. We analyzed the prognostic role of involved structures and their combinations in locally advanced thymomas patients. METHODS: Data on 174 surgically treated locally advanced thymoma patients from 1/01/1990 to 31/12/2015 were reviewed. Clinical and pathological characteristic, involved structures, number of involved structures and different combinations were correlated to cancer specific survival (CSS) using Kaplan-Meier product-limit method. RESULTS: Five and 10-year CSS was 92% and 87%. Masaoka Stage 3 (p < 0.001), absence of pericardial involvement (p = 0.001), number of involved structures (p = 0.018), R0 (p < 0.001) and adjuvant radiotherapy (p = 0.008) were favorable prognostic CSS factors. A significant better prognosis was present in ≤2 involved structures vs >2 involved structures (5- and 10-year CSS: 95% and 93% vs. 80% and 51%). Multivariable analysis confirmed as independent prognostic factor R0 (p = 0.033, hazard ratio [HR]: 0.093, 95% confidence interval [CI] 0.010-0.827) and number of involved structures (p = 0.046, HR: 0.187, 95% CI: 0.036-0.968). In Masaoka Stage 3, patients with ≤2 involved structures had a significant better CSS than patients with >2 (10-year CSS: 98% vs. 73%, p = 0.008). CONCLUSIONS: The number of involved structures and the concomitant involvement of the pericardium seems to be associated with a poor prognosis in surgically treated advanced thymoma patients.

Different View on Tumor Size Dilemma in Tumor-Node-Metastasis Staging System for Thymoma.

BACKGROUND: Although tumor size is included in the definition of T descriptor in the tumor-node-metastasis (TNM) classification of many solid tumors, it is not considered for thymomas. This study aimed to assess the relationship of tumor diameters (the largest tumor diameter [LTD] and the mean tumor diameter [MTD]) with survival in thymoma patients undergoing surgical resection in a single center. METHODS: The study included 127 thymoma patients (age, 49.2 ± 15.2 years; 65 males), who were evaluated based on pathological tumor sizes according to the LTD and MTD ([largest diameter + shortest diameter] / 2) and divided into three subgroups for each parameter as: patients with an LTD of ≤5 cm, 5.1 to 10 cm, and >10 cm and patients with an MTD of ≤5, 5.1 to 10, and >10 cm. RESULTS: In thymoma patients, survival significantly differed according to the presence of myasthenia gravis (p = 0.018), resection status (R0 or R1; p = 0.001), T status (p = 0.015), and the Masaoka-Koga stage (p = 0.003). In the LTD subgroups, the overall survival of those with R0 resection was lower in those with an LTD of 5.1 to 10 cm than in those with an LTD of ≤5 cm (p = 0.051) and significantly lower in those with an MTD of 5.1 to 10 cm than in those with an MTD of ≤5 cm (p = 0.027). In the MTD subgroups, survival decreased as the tumor size increased. CONCLUSION: Both smaller tumor size and complete resection are associated with better survival in thymoma patients. Therefore, the largest or the mean tumor size might be considered as a criterion in the TNM staging for thymoma.

Prosthetic Reconstruction of Superior Vena Cava System for Thymic Tumor: A Retrospective Analysis of 22 Cases.

OBJECTIVE: This study aimed to report our experience in superior vena cava (SVC) resection and reconstruction for 22 thymic tumor patients and to make comparisons with previous related reports. METHODS: A retrospective study on 22 patients (15 thymomas, 7 thymic cancers) who underwent tumor resection with concomitant SVC reconstruction. All the patients underwent vascular conduit reconstruction by the cross-clamping technique. The corresponding data were reviewed, including clinical presentation, operation management (surgery procedure, selection of suitable graft, strategies against SVC syndrome, etc.), postoperative cares (antithrombotic agent application, treatments on brain edema, etc.), and follow-up information. RESULT: Two patients were myasthenic, well controlled by oral pyridostigmine. All resections were radical (R0). Ten patients received induction treatment. All the 15 thymoma patients were Masaoka stage III (type B1-B3). As for thymic cancer, six patients were Masaoka stage III and one was stage IVa. Wedge pulmonary resection was performed in three patients (two right upper lobe, one both upper lobe). Procedures included were single graft replacement in 12 patients, bilateral grafts in 9, and Y-shaped graft in 1 patient. Anticoagulation and dehydration agents were routinely applied after operation. No perioperative mortalities were observed. Major complication rate was 9.1%. The median survival time was 44.2 months (range, 4-92 months). Three- and 5-year overall survival rates were 80.8 and 44.0%, respectively. As for conduit patency, two grafts (9.1%) demonstrated evidence of occlusion during long-term follow-up, but no additional interventions were required due to no complications related. CONCLUSION: Our study, confirming data from existing literature, showed that the prosthetic reconstruction of the SVC system is a feasible additional procedure during resection of thymic tumor infiltrating the venous mediastinal axis, minimally increasing postoperative complications in experienced hands.

Comparison of Subxiphoid and Intercostal Uniportal Thoracoscopic Thymectomy for Nonmyasthenic Early-Stage Thymoma: A Retrospective Single-Center Propensity-Score Matching Analysis.

OBJECTIVE: The aim of this study was to compare early outcome between intercostal uniportal video-assisted thoracoscopic surgery (IU-VATS) versus subxiphoid uniportal video-assisted thoracoscopic surgery (SU-VATS) in thymectomy for non-myasthenic early-stage thymoma. METHOD: Retrospective analysis of 76 cases completed in our hospital from May 2018 to September 2019 with subxiphoid uniportal thoracoscopic thymectomy; a single incision of ∼3 cm was made ∼1 cm under the xiphoid process. The control group included 213 patients who received intercostal uniportal thoracoscopic thymectomy from August 2015, and propensity score matching was conducted. All patients who were clinically diagnosed with thymic tumor before surgery were treated with thymectomy. Perioperative outcomes between SU-VATS (n = 76) and IU-VATS, n = 76 were compared. RESULT: After propensity score matching, there were no statistically significant differences between the two groups in terms of age, gender, disease stage, maximal tumor size, or other baseline demographic and clinical variables. All operation was successfully completed; there were no significant differences in the operative time (88 vs. 81 minutes, p = 0.63), intraoperative blood loss (55 vs. 46 mL, p = 0.47), postoperative drainage time (2.2 vs. 2.5 days, p = 0.72), and postoperative hospital stay (3.2 vs. 3.4 days, p = 0.78) between the two groups. The visual analog scale (VAS) on postoperative days 1, 3, 7, and 30 was less in the SU-VATS group than that in the IU-VATS group. The VAS on days 60 and 180 did not differ significantly between the two groups. CONCLUSION: Thymectomy using SU-VATS is a feasible procedure; it might reduce early postoperative pain and lead to faster recovery.

Surgical outcomes of 215 patients with thymic epithelial tumors: A single-center experience.

OBJECTIVES: To evaluate the oncological prognosis and neurological outcomes for patients with thymic epithelial tumors (TETs) after thymectomy. METHODS: Consecutive patients with TETs who underwent thymectomy at Beijing Hospital from January 2011 to December 2018 were retrospectively enrolled into the study. Clinical, pathological, and perioperative data was collected. Patients were followed-up by telephone interview and outpatient records. Statistical analyses were performed using SPSS version 19.0. RESULTS: A total of 215 patients (115 men and 100 women) were included in this study of which 133 patients (61.9%) had TETs associated with myasthenia gravis (MG), and 82 patients (38.1%) had thymic tumors without MG. A total of 194 (90.2%) patients were successfully followed-up. The median follow-up period was 42 months. The five-year overall survival (OS) rate was 88.6%. MG was the first cause of death for patients with MG (6/10). Prognosis in MG patients was similar to those without MG. Multivariate Cox regression analysis demonstrated that TNM stage III + IV was an independent risk factor for OS. Incomplete resection and younger age were risk factors for tumor recurrence. For patients with MG, the cumulative complete stable remission (CSR) rate increased with the postoperative follow-up period, and the five-year CSR rate was 44.7%. Univariate Cox analysis indicated that age, preoperative MG duration and preoperative medication might correlate with CSR. Multivariate Cox analysis only indicated older age as a negative factor of achieving CSR. CONCLUSIONS: MG had little influence on OS and tumor recurrence of thymic tumors. The new TNM staging system was an independent prognostic factor. Incomplete resection and younger age were risk factors for tumor recurrence. Older age was a negative factor of achieving CSR for thymoma patients with MG after extended thymectomy. KEY POINTS: Significant findings of the study MG was not a prognostic factor for thymic tumors. The new TNM staging system was useful for prediction of prognosis. Incomplete resection and younger age were risk factors for tumor recurrence. Older age led to a lower probability of achieving CSR for thymomatous MG. What this study adds This study had a relatively large sample size of patients with thymic epithelial tumors in a single center. We evaluated not only the oncological prognosis, but also neurological outcomes after thymectomy, which was a more comprehensive assessment of surgical effect for thymic epithelial tumors.

A national analysis of open versus minimally invasive thymectomy for stage I to III thymoma.

OBJECTIVE: The oncologic efficacy of minimally invasive thymectomy for thymoma is not well characterized. We compared short-term outcomes and overall survival between open and minimally invasive (video-assisted thoracoscopic and robotic) approaches using the National Cancer Data Base. METHODS: Perioperative outcomes and survival of patients who underwent open versus minimally invasive thymectomy for clinical stage I to III thymoma from 2010 to 2014 in the National Cancer Data Base were evaluated using multivariable Cox proportional hazards modeling and propensity score-matched analysis. Predictors of minimally invasive use were evaluated using multivariable logistic regression. Outcomes of surgical approach were evaluated using an intent-to-treat analysis. RESULTS: Of the 1223 thymectomies that were evaluated, 317 (26%) were performed minimally invasively (141 video-assisted thoracoscopic and 176 robotic). The minimally invasive group had a shorter median length of stay when compared with the open group (3 [2-4] days vs 4 [3-6] days, P < .001). In a propensity score-matched analysis of 185 open and 185 minimally invasive (video-assisted thoracoscopic + robotic) thymectomy, the minimally invasive group continued to have a shorter median length of stay (3 vs 4 days, P < .01) but did not have significant differences in margin positivity (P = .84), 30-day readmission (P = .28), 30-day mortality (P = .60), and 5-year survival (89.4% vs 81.6%, P = .20) when compared with the open group. CONCLUSIONS: In this national analysis, minimally invasive thymectomy was associated with shorter length of stay and was not associated with increased margin positivity, perioperative mortality, 30-day readmission rate, or reduced overall survival when compared with open thymectomy.

Surgical effect and prognostic factors of myasthenia gravis with thymomas.

BACKGROUND: To evaluate the surgical effect and prognostic factors of extended thymectomy for myasthenia gravis (MG) patients with thymomas. METHODS: Patients with MG with thymomas who underwent extended thymectomy at Peking University People's Hospital and Beijing Hospital between January 2010 and December 2018 were retrospectively enrolled. Patients were followed up by telephone or outpatient record review . Statistical analyses were performed using SPSS version 19.0. RESULTS: A total of 194 patients were included in this study. According to the Osserman classification, there were 56 type I, 52 type IIa, 67 type IIb, 14 type III, and five type IV. Video-assisted thoracoscopic surgery (VATS) thymectomies were performed in 137 patients, and transthymectomies in 57 patients. The average operation time was 136.6 ± 46.5 minutes, average blood loss was 129.3 ± 287.4 mL, and average postoperative stay was 8.3 ± 7.4 days. A total of 170 patients (87.6%) were successfully followed up. The median follow-up period was 45 months, and the five-year overall survival (OS) rate was 81.9%. Cox regression analysis demonstrated that age, Masaoka stage, and recurrence were prognostic factors of OS. Tumor recurrence tended to occur in patients with Masaoka stage III + IV, and age was a protective factor. A total of 20 patients experienced postoperative myasthenic crisis (POMC). Univariate analysis indicated that presence of bulbar symptoms, surgical procedure, and blood loss were risk factors for POMC, but multivariate analysis only indicated the presence of bulbar symptoms as an independent risk factor. A total of 162 patients were evaluated for post intervention MG status. A total of 55 patients achieved complete stable remission; the overall effective rate was 84.5%. Older patients and those with B-type thymomas had a lower probability of achieving complete stable remission. Efficacy was similar in patients who underwent VATS or the transsternal procedure. CONCLUSIONS: Age, Masaoka stage, and recurrence were prognostic factors of OS. Presence of bulbar symptoms was an independent risk factor for POMC. Age and World Health Organization classification influence the postoperative effect of MG. KEY POINTS: Significant findings of the study Age, Masaoka stage, and recurrence were prognostic factors of OS for MG with thymomas. The presence of bulbar symptoms was an independent risk factor for POMC. Age and World Health Organization classification may influence the postoperative effect of MG. What this study adds Our study had a relatively large sample size of MG patients with thymomas only. We emphasize the analysis of the postoperative effect of MG and overall survival for these patients, which is a complement to previous studies.

Prognostic factors after treatment for iterative thymoma recurrences: A multicentric experience.

OBJECTIVES: Thymomas are rare neoplasms with a low recurrence rate, which are preferably surgically treated. Iterative thymoma surgery has not been well investigated yet. Study aim is to analyse prognostic factors after iterative recurrence treatment. METHODS: Clinical, pathological and surgical findings of 155 patients, treated for thymoma recurrence in three high-volume centres from 01/01/1990 to 1/07/2017, were retrospectively reviewed. Recurrence patterns/treatment types (surgery or chemotherapy, radiotherapy or combined) were correlated to overall (OS) and disease free survival (DFS). RESULTS: Myasthenia Gravis was present in 135 (87%) patients. Surgery was performed in 135/155 (87%) patients with 109 (80.7%) complete resections. Sixty (55%)patients experienced a second recurrence surgically treated in 31/60 (52%) cases with 18 (58%) complete resections. Eleven (61%) patients experienced a third recurrence and nine underwent complete resection. Myastenia Gravis (HR: 0.45; 95% CI: 0.20-0.98, p = 0.046), DFS after the initial thymectomy >36 months (HR: 0.9; 95% CI: 0.96-0.99, p = 0.006) and complete second recurrence resection (HR: 1.45; 95% CI 2.07-10.01, p = 0.010) resulted as independent favorable prognostic survival factor. Despite patient selection bias, rewarding long-term survivals was predictable after iterative thymoma surgery (5 and 10 years survival of 79.6% and 64.6%) while a poor prognosis was observed after CT/RT (5 and 10 years OS of 56.7% and 21.5%), Masaoka stage and DFS > 36 months were risk factor for iterative recurrences. CONCLUSIONS: Myasthenia Gravis and long DFS after thymectomy are favorable survival factors for multiple thymoma recurrences. Iterative surgical treatment is a viable therapeutic option associated to long-term survival if technically and clinically feasible.

Long-Term Outcomes After Surgical Resection for Pleural Dissemination of Thymoma.

BACKGROUND: Cases of thymoma with pleural dissemination are occasionally encountered, and their management is difficult. Some reports have noted that surgical treatment for dissemination is effective, although the long-term results and clinical course details remain unclear. The current study investigated the short- and long-term outcomes of surgical resection of pleural dissemination. METHODS: A retrospective review examined the medical records for 38 patients who underwent surgical resection for pleural dissemination occurring synchronously with a primary thymoma or metachronously after complete surgical resection of a primary thymoma between 1996 and 2017 at the authors' institution. Clinical characteristics and prognostic factors were analyzed. RESULTS: The patients were classified into synchronous (n = 21) and metachronous (n = 17) groups. The 10-year overall survival rate was 59% for the synchronous group and 88% for the metachronous group. The median follow-up period for all the patients was 61 months (range 4-225 months). No perioperative deaths occurred. For all the patients, the 5- and 10-year overall survival rates were respectively 91% and 82%, and the 5- and 10-year relapse-free survival rates were respectively 29% and 19%. A significantly worse prognosis was observed for patients 50 years of age or older than for those younger than 50 years (p = 0.02). For 13 patients who underwent repeat resection for pleural dissemination, the prognosis was better than for those without repeat resection (p < 0.01). CONCLUSION: Surgical resection of thymoma with pleural disseminated nodules can be safely performed and provides a favorable long-term outcome. Repeat resection is considered to be effective for achieving a good prognosis.

Impact of Lymph Node Dissection on Thymic Malignancies: Multi-Institutional Propensity Score Matched Analysis.

INTRODUCTION: Surgical resection is a standard treatment for thymic malignancies. However, prognostic significance of nodal metastases and lymph node dissection remains unclear. The aim of this study is to determine prognostic significance of nodal metastases and the role of lymph node dissection (LND) in thymic malignancies. METHODS: Between 2000 and 2013, 1597 patients who underwent thymectomy due to thymic malignancy were included. Predictive factors for nodal metastasis and prognostic significance of LND were evaluated. Patients were divided into two groups: (1) LND+ group, with intentional LND (446 patients, 27.9%); and (2) LND- group, without intentional LND (1151 patients, 72.1%). Propensity score matching was performed between the two groups. RESULTS: Lymph node metastasis was identified in 20 (6.7%) of 298 patients with thymoma and 47 (31.7%) of 148 patients with thymic carcinoma. In multivariable analysis, thymic carcinoma (hazard ratio: 19.2, p < 0.001) and tumor size (hazard ratio: 1.09, p = 0.02) were significant predictive factors for lymph node metastasis. The 10-year freedom from recurrence rate of pN1 and pN2 was significantly worse than that of pN0 (p < 0.001). LND did not increase operative mortality or complication. There was no significant difference in 10-year freedom from recurrence rate between LND+ and LND- groups (82.4% versus 80.9%, p = 0.46 in thymoma; 45.7% versus 44.0%, p = 0.42 in thymic carcinoma). CONCLUSIONS: Lymph node metastasis was a significant prognostic factor in thymic malignancies. Although LND did not improve long-term outcomes in thymic malignancies, LND played a role in accurate staging, and improved prediction of prognosis.

Radiographic Predictors of Resectability in Thymic Carcinoma.

BACKGROUND: The aim of this study was to assess preoperative computed tomography characteristics of thymic carcinomas and to investigate which features could predict an incomplete surgical resection. A secondary aim was to correlate preoperative imaging features with Masaoka stage. METHODS: In this study, approved by our Institutional Review Board, two readers retrospectively reviewed preoperative computed tomography scans at our tertiary referral oncology center between 1994 and 2014. Imaging features analyzed included tumor morphology, infiltration of surrounding mediastinal fat, loss of surrounding fat plane, degree of contact between tumor and great vessels, and associated pulmonary or pleural abnormality. Surgical and pathologic records were reviewed for completeness of surgical resection and Masaoka stage. RESULTS: Forty-one patients were included, with Masaoka stage I (n = 3), stage II (n = 4), stage III (n = 12), and stage IV (n = 22). Twenty-one patients (51%) had a complete surgical resection. Ten had microscopic residual disease (R1) with involved surgical margins at pathology, and 10 patients had macroscopic residual disease (R2) at surgery. In addition to lesion size, the feature associated with incomplete surgical resection was the degree of tumor contact with adjacent mediastinal vessels on the preoperative computed tomography image (p = 0.038). Many of the more common features associated with incomplete resection were also more likely to be present in patients with late Masaoka stage (III/IV), including infiltration of the mediastinal fat, which was present in all 34 patients with Masaoka stage III/IV compared with 5 patients (71%) with stage I/II (p = 0.03). CONCLUSIONS: Preoperative computed tomography imaging features may help to identify patients at risk for an incomplete surgical resection.

Second malignancy versus recurrence after complete resection of thymoma.

Background Patients undergoing complete resection of thymoma occasionally develop a recurrence of thymoma; they are also at risk of developing a second malignancy. The objective of our study was to compare the incidence and mortality of a second malignancy versus a recurrence of thymoma during the postoperative follow-up period after complete resection of thymoma. Methods A retrospective chart review was performed on our prospectively maintained database to identify patients undergoing complete resection of thymoma at our institution between 1991 and 2016. The incidence and related mortality of a second malignancy or recurrence of thymoma were recorded. Results One hundred and sixty-four patients were identified. Follow-up ranged from 1 to 239 months (median 54 months). During follow-up, 12 patients had a recurrence of thymoma and 14 developed a second malignancy. The mean risk ratio of recurrence to second malignancy was 0.58 (95% confidence interval: 0.48-0.69) at 5 years, 0.58 (95% confidence interval: 0.49-0.68) at 10 years, and 0.51 (95% confidence interval: 0.43-0.60) at 15 years. The mean risk ratio of recurrence versus second malignancy for related death was 0.59 (95% confidence interval: 0.50-0.70) at 5 years and 0.61 (95% confidence interval: 0.52-0.72) at 10 years. Conclusion It appears that patients undergoing complete resection of thymoma have a higher incidence of a second malignancy and a greater related mortality rate than a recurrence of thymoma. A multiinstitutional database is required to more rigorously evaluate both risks and to confirm our results.

Role of Surgery in the Treatment of Masaoka Stage IVa Thymoma.

PURPOSE: To analyze the role of surgery in patients with Masaoka stage IVa thymoma treated with multimodality therapy. METHODS: Of 191 patients undergoing surgery for thymoma in our department between January 2002 and December 2015, 39 (20.4%) had Masaoka stage IVa. Histopathological tumor type, myasthenic status of the Osserman-Genkins score, Masaoka stage at the first surgery, neoadjuvant treatment, number and type of surgeries, and survival rates were recorded. RESULTS: Thymoma B2 was the most common histopathological tumor type (n = 16, 41%). Twenty-six (66.7%) patients underwent primary surgeries for Masaoka stage IVa thymoma, whereas nine (23.1%) underwent secondary surgeries and four (10.3%) underwent tertiary surgeries for pleural or pericardial recurrences. Median survival was 132 ± 25 (82-181; 95% confidence interval [CI]) months. Overall 3-, 5-, and 10-year survival rates were 93%, 93%, and 56%, respectively. CONCLUSION: Surgical treatment should be considered as a completion modality to oncological therapy and has the potential to provide long-term survival of Masaoka stage IVa in patients with thymoma. The type of surgery should be determined based on the invasiveness of the lesion.

Propensity Score Adjusted Comparison of Minimally Invasive versus Open Thymectomy in the Management of Early Stage Thymoma.

BACKGROUND: The benefits of minimally invasive versus open thymectomy for the management of thymoma are debatable. Further, patient factors contributing to the selection of operative technique are not well elucidated. We aim to identify the association between baseline patient characteristics with choice of surgical approach. METHODS: Medical records of early stage thymoma (stages I and II) patients undergoing thymectomy between 2005 and 2015 at a single center were identified. Baseline characteristics and surgical outcomes such as prolonged length of stay (LOS ≥ 4 days), 90-day postoperative morbidity, completeness of resection, and recurrence or mortality free rates were compared by surgical approach. RESULTS: Fifty-three patients underwent thymectomy (34 open [64.15%] vs. 19 minimally invasive [35.85%]). There were no statistical differences between the two surgical approaches in demographic variables, smoking status, lung function, comorbidity, tumor size, or staging. Open thymectomy had significantly prolonged LOS (≥4 days) compared with minimally invasive procedures (odds ratio: 11.65; p < 0.01). There were no significant differences in postoperative composite morbidity (p = 0.56), positive margin (p = 0.40), tumor within 0.1 cm of resection margin (p = 0.38), and survival probability estimates (log rank test; p = 0.48) between the two groups. CONCLUSION: Baseline patient characteristics were not associated with surgical approach selected for thymectomy. Minimally invasive thymectomy patients had shorter LOS but no significant differences in 90-day composite morbidity and recurrence or mortality. Larger multicenter studies are needed to evaluate factors contributing to patient selection for each approach, which may include surgeon preference.

Video-Assisted Thoracoscopic Versus Robotic-Assisted Thoracoscopic Thymectomy: Systematic Review and Meta-analysis.

OBJECTIVE: Minimally invasive thoracic surgical procedures, performed with or without the assistance of a robot, have gained popularity over the last decade. They have increasingly become the choice of intervention for a number of thoracic surgical operations. Minimally invasive surgery decreases postoperative pain, hospital stay and leads to a faster recovery in comparison with conventional open methods. Minimally invasive techniques to perform a thymectomy include video-assisted thoracoscopic surgery (VATS) or robotic-assisted thoracoscopic surgery (RATS). In this study, we aim to systematically review and interrogate the literature on minimally invasive thymectomy and draw a meta-analysis on the outcomes between the two approaches. METHODS: An extensive electronic health database search was performed on all articles published from inception to May 2015 for studies describing outcomes in VATS and RATS thymectomy. RESULTS: A total of 350 patients were included in this study, for which 182 and 168 patients underwent RATS and VATS thymectomy, respectively. There were no recorded in-hospital deaths for either procedure. There was no statistical difference in conversion to open, length of hospital stay, or postoperative pneumonia. Operational times for RATS thymectomy were longer. CONCLUSIONS: The VATS and RATS thymectomy offer good and safe operative and perioperative outcomes. There is little difference between the two groups. However, there is poor evidence basis for the long-term outcomes in minimally invasive procedures for thymectomy. It is imperative that future studies evaluate oncological outcomes both short and long term as well as those related to safety.

Induction Therapy versus Initial Surgery in Advanced Thymic Tumors: Perioperative and Oncological Outcome.

Background Despite the intense debate concerning management of advanced thymic tumors, no specific oncological strategies have been yet recommended. We report our 13 years' experience to investigate this issue. Methods From 01/2001 to 12/2013, the clinical data of 28 patients treated for Masaoka stages III-IV thymic tumors were retrospectively reviewed. Eleven potentially nonresectable patients (Group A) underwent induction chemotherapy plus surgery, while immediate surgery was performed in 17 patients (Group B). The endpoint was to compare the two groups on (1) surgical resectability; (2) postoperative course; (3) disease-free survival; and (4) overall survival. Results Both groups were comparable in terms of age, gender, clinical stage, clinical tumor size, histology, and adjuvant therapy. Length of surgery was statistically longer in Group A (p = 0.015). Combined surgery and R0 resection was similarly performed in both groups (p = 0.14 and p = 0.99, respectively). The 3-year overall survival was 71.4% for Group A and 93.3% for Group B (p = 0.84). On the other hand, 3-year disease-free survival was 40.5 and 53.7% for Group A and B, respectively (p = 0.67). At multivariate analysis, gender was the strongest predictor for recurrence (hazard ratio = 5.71 [1.22; 26.67], p = 0.03). Conclusion Our results suggest that induction therapy allows obtaining acceptable clinical responses as well as resectability, survival, and recurrence rates. In selected patients with "clinically resectable" stage III-IV cancers, surgery (as first step of a multimodality therapy) could be a feasible treatment option.

Robotic Surgery for Thoracic Disease.

Robotic surgeries have developed in the general thoracic field over the past decade, and publications on robotic surgery outcomes have accumulated. However, controversy remains about the application of robotic surgery, with a lack of well-established evidence. Robotic surgery has several advantages such as natural movement of the surgeon's hands when manipulating the robotic arms and instruments controlled by computer-assisted systems. Most studies have reported the feasibility and safety of robotic surgery based on acceptable morbidity and mortality compared to open or video-assisted thoracic surgery (VATS). Furthermore, there are accumulated data to indicate longer operation times and shorter hospital stay in robotic surgery. However, randomized controlled trials between robotic and open or VATS procedures are needed to clarify the advantage of robotic surgery. In this review, we focused the literature about robotic surgery used to treat lung cancer and mediastinal tumor.

Multimodality therapy for locally advanced thymomas: A propensity score-matched cohort study from the European Society of Thoracic Surgeons Database.

OBJECTIVE: This study investigated the prognostic impact of multimodality therapies in locally advanced thymomas. METHODS: From January 1990 to January 2010, clinicopathological, surgical, and oncological features were retrospectively reviewed in a cohort of 370 Masaoka-Koga stage III thymomas (World Health Organization classification A to B3) collected from 37 institutions. A multivariate Cox proportional hazard model was created to identify independent predictors of overall, cancer-specific (CSS), and relapse-free survivals. Furthermore, a propensity score-matching analysis for exposure to adjuvant (AT) therapy was generated. RESULTS: Induction therapy and AT were administered to 88 (24.9%) and 245 (69.4%) patients, respectively. Overall, 5- and 10-year overall survival, CSS, and relapse-free survivals were 82.8%, 88.4%, and 80.0%, and 68.9%, 83.3%, and 71.5%, respectively. At multivariable analysis performed in the matched cohort, AT was confirmed as the strongest predictive factor for overall survival (hazard ratio, 2.83; 95% confidence interval, 0.88-9.12; P = .08) and CSS (hazard ratio, 4.70; 95% confidence interval, 1.00-22.2; P = .05). Pathologic T classification (according to International Association for the Study of Lung Cancer and International Thymic Malignancy Interest Group TNM staging proposal) was an independent factor for relapse (hazard ratio, 8.69; 95% confidence interval, 1.08-70.04; P = .04). When CSS was adjusted for T classification, AT confirmed a significant survival advantage for pT3 tumors (P = .04). On the other hand, for thymomas larger than 5 cm, stratifying for tumor size and AT did not affect 5-year CSS (P = .17). CONCLUSIONS: Our results indicate that AT is beneficial for locally advanced thymomas, mainly for specific pathologic features (pT3 or tumor size smaller than 5 cm). Further larger studies are needed to confirm these data.

Long-Term Survival After Surgical Treatment of Thymic Carcinoma: A Retrospective Analysis from the Chinese Alliance for Research of Thymoma Database.

BACKGROUND: Thymic carcinoma is a type of rare and highly malignant tumor that originates from the thymic epithelium. Treatment and prognosis of thymic carcinoma remain controversial. We retrospectively analyzed survival data from a large-sample multicenter database in China. METHODS: The Chinese Alliance for Research of Thymoma constructed a retrospective database of patients with thymic epithelial tumors, which enrolled 1930 patients from January 1996 to August 2013, including 329 with thymic carcinomas. In this study, we analyzed clinical, pathologic, and treatment information, measured long-term survival rates, and identified relevant prognostic factors. RESULTS: Of 329 patients, R0 resection was performed in 211 (57.7 %), R1 in 34 (9.2 %), and R2 in 84 (22.5 %).The 3-, 5-, and 10-year survival rates were 78.3, 67.1, and 47.9 %, respectively. In univariate analysis, early Masaoka-Koga stage, R0 resection, and postoperative radiotherapy were associated with better overall survival.Early Masaoka-Koga stage and postoperative radiotherapy were also associated with disease-free survival. In multivariate analyses, R0 resection, Masaoka-Koga stage, and postoperative radiotherapy were significant prognostic factors of survival. CONCLUSIONS: Complete resection is the preferred primary treatment for thymic carcinoma. R0 resection, early Masaoka-Koga stage, and postoperative radiotherapy are significant predictors of improved survival.

Does the World Health Organization histological classification predict outcomes after thymomectomy? Results of a multicentre study on 750 patients.

OBJECTIVES: The World Health Organization (WHO) thymoma histological classification clinical value remains a controversy. In this study, we evaluated its prognostic significance in patients with thymoma treated with radical intent. METHODS: Six high-volume Italian Thoracic Surgery Institutions collaborated with their own retrospective anonymized datasets. Demographic, clinical, pathological and treatment data were examined. A WHO histological classification (WHO-HC) collapsed scheme (A/AB and B1/B2 types merged) was proposed and compared with the traditional one. Predictors of survival were assessed using a Cox model with shared frailty. Competing-risk regression models were performed to identify the association between individual factors and freedom from recurrence. RESULTS: Between 1990 and 2011, 750 thymomas were operated on in participating centres. Myasthenia gravis was observed in 363 (48%) patients. A complete resection was achieved in 676 (91%) cases. One hundred and nine patients (15%) had a WHO-HC A type, 166 (22%) AB, 179 (24%) B1, 158 (21%) B2 and 135 (18%) B3. The rate of 5-year OS and cumulative incidence of recurrence for all cases was 91% and 0.11, respectively. Five-year survival rates by WHO-HC in the collapsed scheme were A/AB 93%, early-B 90% and advanced-B 85%. Masaoka stage only was demonstrated to be an independent predictor for survival and recurrence. The WHO-collapsed scheme showed a trend in influencing recurrence overall survival development (hazard ratio: 1.32; P = 0.16). CONCLUSIONS: Our results show evidence of lack of significance by WHO-HC in influencing prognosis, even though the proposed collapsed scheme revealed a fair stratification of risk to relapses and better correlation with patients' clinical characteristics.