We ( 1 ) assessed OS of patients to determine if less intensive followup regimens led to worsened survival and asked ( 2 ) whether chest radiograph followup group was inferior to CT scan followup group in detecting pulmonary metastasis ; and ( 3 ) whether less frequent ( 6-monthly ) followup interval was inferior to more frequent ( 3-monthly ) followup in detecting pulmonary metastasis and local recurrence .