Zajicek G
Med Hypotheses. 1980 Jul;6(7):727-33. doi: 10.1016/0306-9877(80)90090-0.
Survival times of treated cancer patients are distributed lognormally. This density function exhibits a peak accompanied by a long tail which asymptotically approaches the abscissa. The lognormal conditional failure rate, known also as force of mortality, which describes the chances of a patient remaining alive, initially climbs, to decline at a later phase. This decline is observable in all survival curves of the "Fourth report on the end results of cancer" in the U.S., and has been documented also by other epidemiological surveys. It implies that with the progression of the disease the chances of the average patient to survive improve. This pattern indicates the existence of a mechanism which is assumed to be associated with neoplasia, and assists the patient to withstand cancer. The initial rise of the force of mortality is assumed here to be associated with cancer treatment which undermines the beneficial role of neoplasia.
接受治疗的癌症患者的生存时间呈对数正态分布。这种密度函数呈现出一个峰值，并伴有一条长尾，该长尾渐近地趋近于横坐标。对数正态条件失效率，也称为死亡率，它描述了患者存活的几率，最初会上升，随后在后期下降。这种下降在美国《癌症最终结果第四次报告》的所有生存曲线中都可观察到，其他流行病学调查也有记录。这意味着随着疾病的进展，普通患者存活的几率会提高。这种模式表明存在一种机制，该机制被认为与肿瘤形成有关，并帮助患者抵御癌症。这里假设死亡率的最初上升与癌症治疗有关，而癌症治疗会削弱肿瘤形成的有益作用。
