Lindqvist C, Teppo L
Br J Cancer. 1978 Jun;37(6):983-9. doi: 10.1038/bjc.1978.143.
A total of 3,169 cases of lip cancer in males and 303 cases in females were diagnosed in Finland and reported to the Finnish Cancer Registry in 1953-73. The diagnosis was verified histologically in 95% of the cases in males and in 92% in females. The mean annual age-adjusted incidence rate was 7·3/10(5) in males and 0·5/10(5) in females. The annual incidence for males has decreased since the early 1960s. The decrease involved all age groups and was not due to a cohort effect. Only a very slight decrease in the risk was observable in females. The incidence was clearly higher in rural than in urban areas, the urban/rural ratio of the age-adjusted incidence rates being 0·6 for males. A decrease in the risk with time was observable for both urban and rural populations. The risk was highest in the northern and eastern parts of the country, for both urban and rural areas. It was concluded that the decrease in the incidence of lip cancer in Finland cannot be accounted for solely by the process of urbanization. An inverse relationship was found between the mean annual amount of solar radiation and the risk of lip cancer. The results are not in accordance with the theory of the association between exposure to actinic radiation and the risk of lip cancer. The synergistic action of some other factors related to outdoor occupation, and probably smoking, would provide a better explanation for the observations in this study.
1953年至1973年期间，芬兰共诊断出3169例男性唇癌病例和303例女性唇癌病例，并上报给了芬兰癌症登记处。95%的男性病例和92%的女性病例经组织学确诊。男性年龄调整后的年均发病率为7.3/10万，女性为0.5/10万。自20世纪60年代初以来，男性的年发病率一直在下降。这种下降涉及所有年龄组，并非由队列效应所致。女性仅出现了非常轻微的风险下降。农村地区的发病率明显高于城市地区，男性年龄调整发病率的城乡比为0.6。城市和农村人口的风险均随时间下降。该国北部和东部地区城乡的风险最高。研究得出结论，芬兰唇癌发病率的下降不能仅用城市化进程来解释。研究发现，年平均太阳辐射量与唇癌风险呈负相关。这些结果与光化辐射暴露和唇癌风险之间的关联理论不符。一些与户外职业相关的其他因素，可能还有吸烟的协同作用，能更好地解释本研究中的观察结果。
