Thymoma

The thymus is derived from 3rd (or 4th) pharyngeal pouch endoderm, attached to anterior mediastinum during development. Thymoma arises from thymic epithelium, ~50% of anterior mediastinal tumors; variable presentation, often with autoimmune abnormalities.

Common Symptoms

Dull pain; diarrhea; dyspnea; jugular venous distension; severe pain; night sweats; fatigue; low fever; recurrent infections

Causes

Thymic epithelial/lymphocytic tumors are most common (95% of thymic tumors); rank 1-3 among mediastinal tumors. Most are benign histologically but some are invasive (malignant thymoma/thymic carcinoma). Symptoms from compression or paraneoplastic syndromes. Small tumors are asymptomatic; larger ones cause chest pain, tightness, cough, anterior chest discomfort. Ignored tumors grow large causing SVC syndrome; severe chest pain, worsening cough, pleural effusion/dyspnea, pericardial effusion/palpitations, bone pain suggest malignancy. Mechanism: 30-60% are invasive, directly invading mediastinal pleura/pericardium/lung/vessels/nerves; may extend to neck/thyroid or through aortic hiatus to liver/kidney/retroperitoneum. Lymphatic metastases to mediastinal/hilar/cervical/supraclavicular/axillary/hepatomesenteric nodes; hematogenous to lung/liver/bone/kidney/brain/spleen/adrenal/breast/ovary. All arise from thymic epithelium; only 4% are pure epithelial. Gross: 1.5-25 cm (usually 5-8 cm), 10-1750 g (usually 20-200 g), dark brown/gray-red, nodular; benign encapsulated, malignant invasive. Microscopy: epithelial (27-34%), lymphocytic (20-27%), mixed (40-55%), spindle cell (2-4%). 2/3 are stage I; <1/3 are II-III.

Treatment

Drug therapy; surgery; supportive care

Prevention

No effective prevention; early diagnosis/treatment key; prevent complications.

Recommended Department

It is recommended to visit the cardiothoracic surgery department; before the visit you may first book an appointment and connect with experts through this platform.

Warm reminder: The above information is provided for health education reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek care at a regular hospital in time.