cystic lymphangioma of mediastinum

例句：

1. 1.The patient was diagnosed with a cystic lymphangioma of the mediastinum.
   患者被诊断出患有胸膜囊肿。
2. 2.This condition is rare but can be life-threatening if not treated promptly.
   这种状况罕见，但如不及时治疗可能会危及生命。
3. 3. The treatment for this condition involves surgery and radiation therapy.
   治疗这种状况的方法包括手术和放疗。