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

Abstract

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.

Keywords

minimally invasive thymectomy - open thymectomy - thymoma

Note

A poster presentation at the 63rd Annual Meeting of the Massachusetts Chapter of the American College of Surgeons held on December 3, 2016, Boston, Massachusetts, United States.

• References

• 1 Friedant AJ, Handorf EA, Su S, Scott WJ. Minimally invasive versus open thymectomy for thymic malignancies: systematic review and meta-analysis. J Thorac Oncol 2016; 11 (01) 30-38
• 2 Chicaiza-Becerra LA, Garcia-Molina M, Gamboa O, Castañeda-Orjuela C. The cost-effectiveness of open or thoracoscopic thymectomy compared to medical treatment in managing Myasthenia gravis without thymomas. Rev Salud Publica (Bogota) 2012; 14 (02) 260-270
• 3 Lee L, Sudarshan M, Li C. , et al. Cost-effectiveness of minimally invasive versus open esophagectomy for esophageal cancer. Ann Surg Oncol 2013; 20 (12) 3732-3739
• 4 Bachmann K, Burkhardt D, Schreiter I. , et al. Long-term outcome and quality of life after open and thoracoscopic thymectomy for myasthenia gravis: analysis of 131 patients. Surg Endosc 2008; 22 (11) 2470-2477
• 5 Wagner AJ, Cortes RA, Strober J. , et al. Long-term follow-up after thymectomy for myasthenia gravis: thoracoscopic vs open. J Pediatr Surg 2006; 41 (01) 50-54 , discussion 50–54
• 6 Youssef SJ, Louie BE, Farivar AS, Blitz M, Aye RW, Vallières E. Comparison of open and minimally invasive thymectomies at a single institution. Am J Surg 2010; 199 (05) 589-593
• 7 Jurado J, Javidfar J, Newmark A. , et al. Minimally invasive thymectomy and open thymectomy: outcome analysis of 263 patients. Ann Thorac Surg 2012; 94 (03) 974-981 , discussion 981–982
• 8 Ye B, Tantai JC, Ge XX. , et al. Surgical techniques for early-stage thymoma: video-assisted thoracoscopic thymectomy versus transsternal thymectomy. J Thorac Cardiovasc Surg 2014; 147 (05) 1599-1603
• 9 Xie A, Tjahjono R, Phan K, Yan TD. Video-assisted thoracoscopic surgery versus open thymectomy for thymoma: a systematic review. Ann Cardiothorac Surg 2015; 4 (06) 495-508
• 10 Raza A, Woo E. Video-assisted thoracoscopic surgery versus sternotomy in thymectomy for thymoma and myasthenia gravis. Ann Cardiothorac Surg 2016; 5 (01) 33-37
• 11 Yang Y, Dong J, Huang Y. Thoracoscopic thymectomy versus open thymectomy for the treatment of thymoma: a meta-analysis. Eur J Surg Oncol 2016; 42 (11) 1720-1728
• 12 Masaoka A, Monden Y, Nakahara K, Tanioka T. Follow-up study of thymomas with special reference to their clinical stages. Cancer 1981; 48 (11) 2485-2492
• 13 Koga K, Matsuno Y, Noguchi M. , et al. A review of 79 thymomas: modification of staging system and reappraisal of conventional division into invasive and non-invasive thymoma. Pathol Int 1994; 44 (05) 359-367
• 14 Seely AJ, Ivanovic J, Threader J. , et al. Systematic classification of morbidity and mortality after thoracic surgery. Ann Thorac Surg 2010; 90 (03) 936-942 , discussion 942
• 15 Ivanovic J, Al-Hussaini A, Al-Shehab D. , et al. Evaluating the reliability and reproducibility of the Ottawa Thoracic Morbidity and Mortality classification system. Ann Thorac Surg 2011; 91 (02) 387-393
• 16 Schumacher ED, Roth O. Thymektomie bei einem Fall von morbus Basedowi mit myasthenie. Mitt Grenzgeb Med Chir 1913; 25: 746-765
• 17 Blalock A, Harvey AM, Ford FR, Lilienthal JL. The treatment of myasthenia gravis by removal of the thymus gland: preliminary report. J Am Med Assoc 1941; 117 (18) 1529-1533
• 18 Chao YK, Liu YH, Hsieh MJ. , et al. Long-term outcomes after thoracoscopic resection of stage I and II thymoma: a propensity-matched study. Ann Surg Oncol 2015; 22 (04) 1371-1376
• 19 Ye B, Tantai JC, Li W. , et al. Video-assisted thoracoscopic surgery versus robotic-assisted thoracoscopic surgery in the surgical treatment of Masaoka stage I thymoma. World J Surg Oncol 2013; 11: 157
• 20 Chung JW, Kim HR, Kim DK. , et al. Long-term results of thoracoscopic thymectomy for thymoma without myasthenia gravis. J Int Med Res 2012; 40 (05) 1973-1981