Melanoma in older patients: declining gap in survival between younger and older patients with melanoma

Background: Older people have the highest incidence of melanoma and the population in most Western countries is ageing. We evaluated how the gap in incidence and survival between younger and older patients has developed during the past decades. Material and methods: All patients diagnosed with cutaneous melanoma between 1989 and 2015 (n = 84,827) were identified from the Netherlands Cancer Registry. Elderly were defined as aged ≥70 years. Differences in patient and tumor characteristics were described, age-specific incidence rates were calculated, and relative survival (RS) and multivariable analyses estimating the Relative Excess Rate of dying (RER) were conducted Results: In older men, the melanoma age-standardized incidence increased from 18 to 103/100,000 person-years (py) between 1989 and 2015 and in older women from 23 to 70/100,000 py. In younger men and women, it increased from 8 to 21 and from 13 to 28/100,000 py, respectively. Median Breslow thickness declined from 1.8 to 1.1 mm and from 1.6 to 1.1 mm in older men and women (2003 versus 2015), and from 1.1 to 0.9 mm and 0.9 to 0.8 mm in younger men and women. In older men, 5-year RS increased from 67% (95% CI: 63%–72%) in 1989–1997 to 85% (95% CI: 83%–87%) in 2007–2015 and in older women from 81% (95% CI: 78%–85%) to 89% (95% CI: 87%–91%). In younger men and women, RS increased from 82% (95% CI: 81%–83%) to 90% (95% CI: 90%–91%) and from 92% (95% CI: 92%–93%) to 96% (95% CI: 95%–96%). After case-mix correction , older men and women no longer showed an improved survival over time (RER 2010–2015 versus 2003–2009: 0.97; 95% CI: 0.81–1.16 and 0.95; 95% CI: 0.79–1.16). Whereas in younger men and women survival remained improved (RER 0.75; 95% CI: 0.67–0.83 and 0.77; 95%CI: 0.67–0.89). Conclusion: The gap in melanoma incidence between younger and older people is increasing due to a strong increase in incidence in older adults. Disparities in survival are declining, related to a narrowing gap in Breslow thickness.

研究背景：黑色素瘤（melanoma）的发病率在老年人群中居于最高水平，且多数西方国家的人口正趋于老龄化。本研究旨在评估近数十年来，年轻与老年患者之间的发病率与生存率差距的变化趋势。
材料与方法：本研究从荷兰癌症登记处（Netherlands Cancer Registry）提取了1989年至2015年间确诊的所有皮肤黑色素瘤（cutaneous melanoma）患者数据，共计84827例。本研究将老年人群定义为年龄≥70岁者。研究描述了患者与肿瘤特征的差异，计算了年龄特异性发病率，并开展了相对生存率（relative survival, RS）分析以及用于估算相对死亡超额率（Relative Excess Rate of dying, RER）的多变量分析。
研究结果：1989年至2015年间，老年男性的黑色素瘤年龄标化发病率从18/10万人年（person-years, py）升至103/10万人年，老年女性则从23/10万人年升至70/10万人年。年轻男性与年轻女性的发病率分别从8/10万人年升至21/10万人年、13/10万人年升至28/10万人年。2003年与2015年，老年男性与老年女性的中位布雷斯洛厚度（Breslow thickness）分别从1.8 mm降至1.1 mm、1.6 mm降至1.1 mm；年轻男性与年轻女性则分别从1.1 mm降至0.9 mm、0.9 mm降至0.8 mm。老年男性的5年相对生存率从1989-1997年的67%（95%置信区间：63%~72%）升至2007-2015年的85%（95%置信区间：83%~87%）；老年女性则从81%（95%置信区间：78%~85%）升至89%（95%置信区间：87%~91%）。年轻男性与年轻女性的5年相对生存率分别从82%（95%置信区间：81%~83%）升至90%（95%置信区间：90%~91%）、92%（95%置信区间：92%~93%）升至96%（95%置信区间：95%~96%）。经病例组合校正后，老年男性与女性的生存率未再随时间出现显著提升（2010-2015年相较于2003-2009年的相对死亡超额率RER分别为0.97；95%置信区间：0.81~1.16 与0.95；95%置信区间：0.79~1.16）。而年轻男性与女性的生存率仍持续改善（RER分别为0.75；95%置信区间：0.67~0.83 与0.77；95%置信区间：0.67~0.89）。
研究结论：由于老年人群黑色素瘤发病率的大幅上升，年轻与老年群体间的黑色素瘤发病率差距正持续扩大。而生存率的差异则在不断缩小，这与布雷斯洛厚度差距的收窄密切相关。