Intracaval and intracardiac extension of invasive thymoma complicated by superior and inferior vena cava syndrome

Intracardiac Thymoma with Superior Vena Cava and Left Brachiocephalic Vein Extension: A Case Report

Thymomas are common anterior mediastinal tumors with a relatively favorable prognosis compared to that of other types of thoracic malignancies. However, thymomas that invade surrounding structures, such as the heart or vena cava, have been infrequently reported, and intracardiac thymomas are exceedingly rare. Treatment of invasive thymoma is difficult because the high rate of incomplete resection results in a high rate of recurrence. Herein, we present a rare case of a thymoma that originated in the right atrium and extended into the superior vena cava and brachiocephalic vein.

Case report: Complete resection of invasive thymoma invading the superior vena cava and right atrium under cardiopulmonary bypass support

Here we describe an uncommon case of a 48-year-old male patient with an invasive thymoma invading the superior vena cava, bilateral innominate veins, right internal jugular vein, right subclavian vein, right atrium, azygos vein, and part of the lung tissues. The tumor was resected entirely under cardiopulmonary bypass support, and the venous bypass using a vascular graft was successfully established between the left innominate vein and the right atrium. The postoperative course was uneventful, and the patient was discharged 15 days after surgery without complications.

Thymomas With Intravascular and Intracardiac Growth

Thymomas are derived from the epithelial component of the thymus and constitute the most common tumor of the anterior mediastinum. These neoplasms are considered malignant for their potential for invasion and metastases. Several histopathologic subclassification schemes have been proposed over the years, however, correlation of histotypes with prognosis remains controversial. In contrast, studies invariably have shown that staging and resection status correlate with oncologic behavior and disease outcomes. In this regard, several staging systems have been presented, though transcapsular invasion and degree of involvement of adjacent anatomic structures are common denominators of all schemes. Involvement of the great vessels and heart most commonly results from direct invasion, which may lead to unusual clinical presentations such as superior vena cava syndrome. Moreover, intravascular and intracardiac growth with or without direct mural invasion rarely occurs. We provide an overview of thymomas with intravascular and intracardiac involvement.

Invasive thymoma extending to the right atrium with superior vena cava syndrome presenting massive intracardiac thrombosis immediately after the start of chemotherapy: an autopsy case report

Invasive thymomas with intraluminal tumor thrombi are rare. Removal of the thymoma and infiltration of the superior vena cava (SVC) is a curative alternative. We report an autopsy case of invasive thymoma with intraluminal growth into the intracardiac right atrium extension. Furthermore, the patient died of massive intracardiac thrombosis 5 days after the start of chemotherapy. A 66-year-old man with SVC syndrome was referred to our hospital. He had been aware of swelling of the face for 6 months. The patient was diagnosed with invasive thymoma by a CT-guided needle biopsy of the anterior mediastinal mass. Contrast-enhanced chest computed tomography showed a mass in the anterior mediastinum extending to the SVC and right atrium. As a result of discussion with surgeons and radiotherapists, we planned a multidisciplinary treatment in which neoadjuvant chemotherapy would reduce the tumor size, and surgery and postoperative radiotherapy were followed by chemotherapy. He was administered neo-adjuvant chemotherapy with CBDCA + PTX (carboplatin, area under the curve = 6, and paclitaxel, 200 mg/m²). On the 4th day of chemotherapy, he suddenly developed obstructive shock due to intracardiac thrombosis in the right ventricle. We believe that chemotherapy may trigger rapid thrombus formation. If an invasive thymoma spreads into a large vessel or the right atrium, surgical treatment should be considered if possible. However, if surgery is impossible, administration of anticoagulants should be considered to prevent thrombus formation before chemotherapy.

An invasive thymoma extending into the superior vena cava and right atrium

Invasive thymoma commonly infiltrates mediastinal structures; however, intracardiac extension from an intracaval growth is rare. An unusual case of an invasive thymoma protruding into the RA is here described. A left brachiocephalic vein (LBCV) tumor appeared through the thymic veins of a 50-year-old female patient. The patient underwent a combined resection of the invasive tumor and superior vena cava (SVC) and right atrium (RA) under cardiopulmonary bypass (CPB). Pathologic examination revealed this to be a WHO type B3 thymoma, Masaoka stage III. Following surgery, the patient's symptoms disappeared, and the quality of life improved. The patient was then introduced to radiotherapy and chemotherapy. This present case indicates that surgical treatment can create the opportunity for radiotherapy and chemotherapy, and is suitable and necessary for the treatment of invasive thymoma.

[Surgical Treatment of Malignant Thymoma Invading the Superior Vena Cava]

恶性胸腺瘤侵犯上腔静脉在临床上较常见，但其外科治疗相关总结经验较少。本文详细介绍了恶性胸腺瘤侵犯上腔静脉外科治疗的发展历史与治疗现状，结合典型病例对恶性胸腺瘤合并上腔静脉综合征的影像学表征进行了探讨，重点描述了以外科手术为主的恶性胸腺瘤侵犯上腔静脉的综合治疗方法。该手术复杂程度高，手术风险大，为便于广大年轻医生的学习了解与实践操作，作者系统介绍了恶性胸腺瘤联合上腔静脉切除的4种手术方法，希望对年轻医生的学习应用有所裨益。

Superior vena cava syndrome from an invasive thymoma with transcaval invasion to the right atrium

Invasive thymoma with transcaval extension to the right atrium is a rare cause of superior vena cava syndrome. We present a case on a 74-year-old female presenting with dyspnea on exertion, and facial and upper extremity swelling. Physical examination revealed mild facial swelling, non-pitting edema involving the upper extremities and distention of superficial veins of the anterior chest wall and jugular veins. An echocardiogram showed moderate right atrial dilation with a mobile mass in the atrial cavity prolapsing through the tricuspid valve. Cardiac magnetic resonance imaging revealed a 9.9 × 4.3 cm heterogeneous mass in the anterior mediastinum compressing the superior vena cava and endovenously extending into the right atrium. Tissue biopsy of the mediastinal mass revealed a type B1 thymoma, further staged as a Masaoka IVa invasive thymoma that underwent successful en bloc resection followed by removal of intracaval and right atrial mass.

Successful resection of thymoma directly invading the right atrium under cardiopulmonary bypass

We present the case of an invasive thymoma with severe compression of the right atrium, and infiltration of the atrial wall, causing a superior vena cava (SVC) syndrome. The tumour was resected under cardiopulmonary bypass en bloc with the atrial wall. A bovine pericardial patch was used for atrial reconstruction. We obtained a complete resection of the tumour and regression of symptoms, and, after 1 year of the follow-up, no signs of recurrence are evident. To our knowledge, this is the first case of thymoma directly invading the right atrium, without involvement of the SVC. In this setting, the aggressive surgical approach led to an immediate resolution of the symptoms and contributed to prolonged long-term survival.