SEP has a better prognosis than solitary bone plasmacytoma (SBP) and MM.We report a patient with a mediastinal mass extending to the anterior chest wall without bony destruction.

• 我们报告一名主诉前胸壁有肿块的病人，胸部电脑断层检查发现一巨大均质的前纵膈腔肿瘤往前延伸到前胸壁但没有合并骨头的破坏。