Surgical treatment of benign mediastinal teratoma: summary of experience of 108 cases
Authors: Tian Zhenhuan , Liu Hongsheng , Li Shanqing , Chen Yeye , Ma Dongjie , Han Zhijun , Huang Cheng 
Published: February 2020

Abstract
Background
Mediastinal teratoma is a rare disease, many cases were reported before, but few articles focus on large case analyses. The objective of this article is to summarize the clinical characteristics of benign mediastinal teratoma and the experience of surgical treatment, especially thoracoscopic surgery for benign mediastinal teratoma.

Methods
The clinical data of 108 patients with benign mediastinal teratoma confirmed by operation and pathology from January 1992 to January 2018 were analyzed retrospectively. The clinical symptoms, imaging examination, surgical methods and prognosis of all patients were analyzed. We compared the difference of thoracoscopic surgery and thoracotomy surgery using 102 patients underwent only chest surgery. Normally distributed continuous variables were compared by independent sample t test. Categorical variables were analyzed by chi-square test.

Results
Imaging examination showed that all 108 cases of mediastinal teratoma were located in the anterior region of mediastinum. All cases underwent surgical resection, postoperative pathology confirmed that all cases were benign. 1 case was taken simple neck collar incision, 5 case was taken median thoracotomy combined with neck incision, other 102 cases were taken thoracoscopic surgery (22) or thoracotomy surgery (80). 4 cases were treated with partial pericardial resection due to adhesions, 12 cases underwent partial pericardial resection, 5 cases underwent lobectomy, 9 cases underwent wedge resection of lobe, and 2 patients underwent anonymous vein angioplasty. 1 case underwent second operation because of postoperative bleeding, 1 case of chylothorax, 1 case of recurrent laryngeal nerve injury, 2 cases of wound infection, 1 case of secondary pulmonary infection. 106 cases were followed up, period from 12 months to 10 years, no recurrence of tumor was found. Comparing to take thoracotomy surgery, patients underwent thoracoscopic surgery has strong advantage on intraoperative blood loss and hospital stay days after surgery (P < 0.05). tumor maximum diameter is larger for thoracotomy surgery group, as well as more patients suffer estimated adhesions from preoperative imaging. so we compared above parameters in patients with tumor diameter less than 10 cm with or without estimated adhesions from preoperative imaging, a strong advantage still can be found in thoracoscopic surgery group, inpatients with estimated adhesions from preoperative imaging, intraoperative blood loss (38.75 ± 15.53 vs 169.17 ± 208.82., P = 0.04) and hospital stay days after surgery (5.50 ± 0.93 vs 9.43 ± 6.54., P = 0.04) were better. In patients without estimated adhesions from preoperative imaging, intraoperative blood loss (46.67 ± 10.00 vs 110.53 ± 123.13., P = 0.06) and hospital stay days after surgery (4.70 ± 1.16 vs 7.53 ± 2.32., P = 0.01) were better. Especially, in thoracoscopic surgery group, hospital stay days after surgery was significantly shorter.

Conclusion
The clinical manifestations and imaging performance of benign mediastinal teratoma were complicated, and the surgical treatment was effective. Compared with traditional thoracotomy surgery, thoracoscopic surgery can improve patients’ quality of life, less intraoperative blood loss, and less hospital stay days after surgery, so if condition is permitted, thoracoscopic surgery should be a better choice.