X-rays should be obtained for persons over age50, in whom metastatic tumors are more likely, and those under age20, in whom symptomatic congenital or developmental anomalies may be present.

• 年龄超过50岁，很可能是转移性肿瘤，而年龄在20岁以下者同可能有闰状性的先天性或发育性异常常存在，故应作X线检查。