We welcome the discussion raised by Vogl¹ with regard to our recent article.² The period of immortality is best described as the duration in which a patient cannot die as a result of operating definitions within a retrospective analysis. This is often a concern with retrospective studies due to the inability to assign patients properly in an intention-to treat fashion. Any surgical patient who did not receive therapy on day 0 was by definition immortal until the date of surgery because a death before surgery would place them in the nonsurgical cohort. This bias also is equally valid for patients who underwent radiation and chemotherapy. The time to surgery was, in fact, brief, with a median of 22 days (interquartile range, 0 to 64 days).

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回复SE Vogl

我们欢迎Vogl ¹对我们最近的文章进行的讨论。²永生期最好描述为回顾性分析中由于操作定义而导致患者死亡的持续时间。由于无法按意向治疗的方式正确分配患者，因此回顾性研究通常会对此予以关注。从定义上讲，任何在第0天未接受治疗的手术患者在手术之日之前都是不死的，因为手术前的死亡会将他们置于非手术队列中。这种偏见对接受放射和化学疗法的患者同样有效。实际上，手术时间很短，平均时间为22天（四分位间距为0到64天）。