並列摘要
Growing teratoma syndrome is defined as progressively enlarging masses of mature as progressively enlarging masses of mature teratoma following or during chemotherapy for nonseminomatous germ-cell tumors. Typically there is associated normalization of initially elevated serum markers. Complete surgical resect is the treatment of choice for growing teratoma syndrome. Being a benign condition, the prognosis of growing teratoma syndrome is good. Familiarity with this unusual entity is important to avoid confusion with advancing malignancy.