Thymic epithelial tumors represent the most common neoplasms of the anterior mediastinum, while atypical type A thymoma is a rare subtype of thymoma. On the morphological basis of type A thymoma, this tumor exhibits some atypical histological features, such as abundant cells, increased mitotic counts, tumor necrosis, and increased Ki67 index. At present, the clinical and pathological data of this tumor is still available. Since it was formally named, 16 cases have been reported around the world. In order to improve the understanding of the disease, this article reviews the related literature and tries to elaborate the atypical type A thymoma from the aspects of pathological features, clinical manifestations, epidemiology and differential diagnosis.
Objective To compare the different surgical treatment methods of thymoma combined with myasthenia gravis (MG), and to discuss the clinical effectiveness of thoracoscopic combined mediastinoscopic extended thymectomy. Methods We retrospectively analyzed the clinical data of 58 patients of thymoma combined with myasthenia gravis in Northern Jiangsu People's Hospital between 2011 and 2016 year. According to the operation method, the patients were divided into three groups including a group A for thoracoscopic thymectomy (n=32), a group B for thoracoscopic combined mediastinoscopic thymectomy (n=15), and a group C for transsternal thymectomy (n=11). The clinical effects were observed and compared. Results In the group A and the group B, the bleeding volume, postoperative hospital stay and other complications were significantly lower than those in the group C with statistical differences (P<0.05). The incidence of myasthenic crisis in the group B (6.7%) was less than that in the group C (36.4 %), but the difference was not statistically different (P=0.058). The operation time of the three groups was 122.0 ± 39.4 min, 130.3 ± 42.5 min, and 142.3 ± 40.8 min respectively with no statistical difference between the two groups (P>0.05). The rate of dissection grade in the group B (grade 1, 12 patients, 80%) was significantly greater than that in the group A (grade 1, 14 patients, 43.8%,P<0.05). The effective rate of the group A, the group B, the group C was 84.4%, 93.3% and 90.9%, respectively with no statistical difference between groups (P>0.05). Conclusion The thoracoscopy combined mediastinoscopic thymectomy not only has the advantages of less trauma, quicker recovery and fewer complications, but also can more thoroughly clean the thymus and adipose tissue, which can achieve the same therapeutic effect as the transsternal thymectomy.
ObjectiveTo assess the correlation of WHO pathological classification and Masaoka stage of thymomas with its prognosis.MethodsA total of 468 patients with thymomas who received surgeries during 2009-2019 in Huashan Hospital, Fudan University, were collected. There were 234 males and 234 females with an average age of 21-83 (49.6±18.7) years. A total of 132 patients underwent video-assisted thoracic surgery (VATS) and 336 patients underwent thymectomy with median sternal incision. The follow-up time was 5.7±2.8 years. The clinical data of the patients were analyzed.ResultsThe amount of intraoperative bleeding was 178.3±133.5 mL in the median sternal incision group, and 164.8±184.1 mL in the VATS group (P=0.537). The operative time was 3.3±0.7 h in the median sternal incision group and 3.4±1.2 h in the VATS group (P=0.376). Postoperative active bleeding, phrenic nerve injury and chylothorax complications occurred in 8 patients, 9 patients and 1 patient in the VATS group, respectively, and 37 patients, 31 patients and 7 patients in the median sternal incision group, respectively. There was no statistical difference between the two groups (P=0.102, 0.402, 0.320). The 5-year cumulative progression free survival (PFS) rates of patients with WHO type A, AB, B1, B2, B3 and C thymomas were 100.0%, 100.0%, 95.7%, 81.4%, 67.5% and 50.0%, respectively (P<0.001). The 5-year PFS rates of patients with Masaoka stageⅠ-Ⅳ thymomas were 96.1%, 89.2%, 68.6% and 19.3%, respectively (P<0.001). The 5-year PFS rate was 87.3% in patients with myasthenia gravis (MG) and 78.2% in patients without MG (P<0.001). The 5-year PFS rates of patients with different surgeries were 82.4% and 83.8%, respectively (P=0.904). ConclusionWHO pathological classification and Masaoka stage have significant clinical prognosis suggestive effect. Thymoma patients combined with MG have better prognosis, which suggests early diagnosis and treatment of thymoma are important.
Objective To compare the differences in clinicopathological features, molecular phenotypes, and prognosis between atypical type A thymoma (AAT) and classic type A thymoma (TAT), and to clarify the aggressive nature of AAT. Methods The data of AAT patients (AAT group) and classic TAT patients (TAT group) who underwent surgical resection for thymoma at West China Hospital of Sichuan University between January 2016 and November 2024 were retrospectively collected. Comparisons on the clinical data, histopathology, immunohistochemistry (CD20, Ki-67), GTF2I mutation status, and survival outcomes were performed between the two groups. Results A total of 53 patients were enrolled, including 22 in the AAT group and 31 in the TAT group. There was no significant difference in age, sex, or initial presenting symptoms between the two groups (P>0.05). Compared with the TAT group, the AAT group had larger tumors [(5.6±2.7) vs. (4.1±2.0) cm, P=0.043], a lower proportion of Masaoka stage Ⅰ (31.6% vs. 61.3%, P=0.041), and worse survival outcomes [progression-free survival: hazard ratio (HR)=2.87, 95% confidence interval (CI) (1.42, 5.81), P=0.004; overall survival: HR=1.96, 95%CI (1.02, 3.78), P=0.013]. Pathologically, the AAT group showed more mitotic figures (mean 6/2 mm2), and tumor necrosis was observed in 45.5% of cases. There was no statistically significant difference in the CD20 expression rate (20.0% vs. 41.9%), Ki-67 index [(11.0±6.0)% vs. (8.0±6.9)%], or GTF2I mutation rate (86.7% vs. 92.3%) between the two groups (P>0.05). Conclusions AAT is a subtype of TAT with distinct aggressive pathological features, including higher mitotic activity, a tendency for necrosis, and a greater propensity for recurrence and metastasis. Pathological diagnosis should integrate morphology and molecular testing to guide more aggressive treatment and follow-up strategies.
Objective To evaluate the risk factors of the patients with myasthenia gravis (MG) after resection of thymoma. Methods We retrospectively analyzed the clinical data of 126 thymoma patients without preoperative MG who underwent a thymectomy in our hospital from June 2002 through May 2015. There were 51 males and 75 females at age of 51.71±14.06 years. The risk factors for MG after resection of thymoma were evaluated. Results MG occurred in nine patients after resection of thymoma (7.1%). Incomplete resection (P=0.024), A and AB type of WHO classification (P=0.048), concomitant autoimmune diseases (P=0.024), postoperative pulmonary infection (P=0.036) were the risk factors for the MG after resection of thymoma. Postoperative radiotherapy and chemotherapy (P=0.011) reduced the risk for the patients with incomplete resection or invasive thymoma. Conclusion Incomplete resection, A and AB type of WHO classification, concomitant autoimmune diseases, postoperative pulmonary infection are considered as the risk factors for MG after resection of thymoma, and postoperative radiotherapy and chemotherapy should be performed for the patients with incomplete resection or invasive thymoma.
ObjectiveTo compare the efficacy and safety of video-assisted thoracoscopic surgery (VATS) thymectomy for the treatment of thymoma through subxiphoid uniportal approach using double sternum retractors, and subxiphoid and subcostal arch approach. Methods We retrospectively analyzed the clinical data of the patients diagnosed with thymoma who underwent VATS thymectomy from June 2023 to June 2024 in West China Hospital. Patients were categorized based on the surgical approach into two groups: a subxiphoid uniportal VATS thymectomy (SUVT) group and a subxiphoid and subcostal arch VATS thymectomy (SASAT) group. Comparisons were made between the two groups regarding surgical duration, intraoperative blood loss, postoperative drainage, thymoma size and location, and postoperative pain assessed using the visual analogue scale (VAS). ResultsThe SUVT group consisted of 20 patients, including 11 males and 9 females, with an average age of (51.5±14.3) years. The SASAT group comprised 40 patients, including 26 males and 14 females, with an average age of (50.0±13.0) years. Compared to the SASAT group, the SUVT group had significantly larger thymomas [ (5.9±2.7) cm vs. (4.2±2.1) cm, P=0.010] and a higher proportion of neoplasms located in the superior mediastinum (30.0% vs. 2.5%, P=0.007). Additionally, the VAS pain scores on postoperative days 3, 7, and 30 were significantly lower in the SUVT group compared to the SASAT group (P<0.05). There were no statistical differences between the two groups in demographic characteristics, operative time, intraoperative blood loss, duration and volume of postoperative drainage, length of postoperative hospital stay, or the VAS pain score on the first postoperative day. Conclusion SUVT using double sternum retractors significantly reduces postoperative pain and provides superior efficacy in the resection of larger thymomas or those situated in the superior mediastinum.
Abstract： Objective To investigate the expression and correlation of phosphatase and tensin homologue deleted on chromosome ten(PTEN)， epidermal growth factor receptor(EGFR) and Ki-67 in human thymic tumors, and their possible role in tumor genesis， infiltration and metastasis. Methods The expression of PTEN， EGFR and Ki-67 were detected by using SP immunohistochemical technique in 45 cases of thymic tumors and 5 cases of normal thymic tissues. Results In 5 cases of normal thymic tissues, the expression of PTEN was bly positive, whereas EGFR and Ki -67 were weakly positive or negative. In 45 cases of thymic tumors, the positive ratio of PTEN were significantly reduced from benign thymoma， invasive thymoma to thymic carcinoma (χ2=7.808, P=0.020), but the positive ratio of EGFR and Ki-67 were gradually increased(χ2=8.032, 0.018，7.006；P=0.030). The positive ratio of PTEN， EGFR and Ki-67 protein were significantly related to Levine classification, Masaoka staging and lymph node metastasis (Plt;0.05). PTEN positive cases were negatively correlated with EGFR and Ki-67(r=－0.632，－0.653；Plt;0.01), EGFR positive cases were positively correlated with Ki-67 in thymic tumors(r=0.807,Plt;0.01). Conclusions Reduced or absent PTEN and increased EGFR and Ki-67 expression might play an important role in the genesis， invasiveness and metastasis of thymic tumors. The expression of PTEN is bly associated with the expression of abnormal EGFR and Ki-67. Detection of the three protein expressions simultaneously might be more helpful in making an early diagnosis of the tumors jndgement of theirs malignant degree，invasiveness and metastasis capacity, as well as the prognosis.
Objective To investigate the effects of inflammatory reaction of thymomas with myasthenia gravis (MG) treated by traditional thoracotomy and minimally invasive surgery. Methods A total of 40 thymomas patients (Mssaoka Ⅰ or Ⅱ) with myasthenia gravis from August 2014 to June 2015 were treated by traditional thoracotomy (n=20) or video-assisted thoracoscopic surgery (n=20). The serum levels of IL-6, IL-8, TNF-α, CRP and CORT were measured by enzyme-linked immunosorbent assay (ELISA) methods at before anesthesia (T1), after anesthesia (T2), 2 h after skin cut (T3), 24 h post-operation (T4), 48 h post-operation (T5) and 72 h post-operation (T6) respectively. Perioperative parameters were also reported. The statistics analysis was performed by SPSS 17.0 software. Results The serum levels of IL-6, IL-8, TNF-α, CRP and CORT had no significant difference between T1 and T2, T2 and T3 (allP value>0.05) in both groups. But the serum levels of these factors after operation were obviously higher than that of before operation, commonly the highest level was reached at T4 (allP value>0.01), and also was higher at T6 than that of before the operation (allP value<0.01), except the level of TNF-α recovered rapidly to the level of before operation (allP value>0.05) in the VATS group. The operation time, postoperative drainage tube indwelling time and incision healing time in the VATS were lower than that in the control group (allP value<0.05). Conclusion VATS could be widely applied in clinical practice with lowering operative trauma and reducing the degree of inflammatory reaction.
Thymoma complicated with polymyositis and myasthenia gravis is a rare case, which can be clearly diagnosed and given symptomatic treatment according to its own diagnostic criteria, imaging and laboratory examinations. This paper reports the clinical data of a thymoma patient with polymyositis and myasthenia gravis admitted to the Seventh Affiliated Hospital of Sun Yat-Sen University, and discusses the possible pathogenesis and treatment methods.