Background

Previous studies have shown that colorectal cancer incidence is increasing among younger adults (aged <50 years) in multiple high-income western countries in contrast with stabilising or decreasing trends in incidence in older adults (aged ≥50 years). This study aimed to investigate contemporary colorectal cancer incidence trends in younger adults versus older adults.

Methods

Colorectal cancer incidence data, including year of diagnosis, sex, and 5-year age group for 50 countries and territories, were extracted from the WHO–International Agency for Research on Cancer Cancer Incidence in Five Continents Plus database. The Human Development Index 2022 was retrieved from the United Nations Development Programme and grouped into very high (>0·80), high (0·70–0·79), medium (0·55–0·69), and low (<0·55) categories. Age-standardised incidence rates (ASR) per 100 000 person-years of early-onset (diagnosed between ages 25 to 49 years) and late-onset (diagnosed between ages 50 to 74 years) colorectal cancer (ICD 10th revision, C18–20), diagnosed between 1943–2003 and 2015–17, were calculated using the direct method and Segi–Doll world standard population). The primary study objective was to examine contemporary colorectal cancer incidence trends in younger adults versus older adults using data until 2017 from 50 countries and territories. Temporal trends were visualised and quantified with joinpoint regression, stratified by age at diagnosis (25–49 years or 50–74 years). Average annual percentage changes (AAPC) were estimated.

Findings

In the most recent 5 years (2013–17 for all countries analysed, except for Japan [2011–15], Spain [2012–16], and Costa Rica [2012–16]), the incidence rate of early-onset colorectal cancer was highest in Australia (ASR 16·5 [95% CI 16·1–16·9]), the USA (Puerto Rico; 15·2 [14·2–16·2]), New Zealand (14·8 [14·0–15·6]), the USA (14·8 [14·7–14·9]), and South Korea (14·3 [14·0–14·5]) and lowest in Uganda (4·4 [3·6–5·2]) and India (3·5 [3·3–3·7]). The highest incidence rates among older adults were found in the Netherlands (168·4 [166·9–170·0]) and Denmark (158·3 [155·8–160·9]) and the lowest were in Uganda (45·9 [38·5–51·4]) and India (23·5 [22·8–24·3]). In terms of AAPC, in the most recent 10 years, incidence rates of early-onset colorectal cancer were stable in 23 countries, but increased in 27 countries with the greatest annual increases in New Zealand (AAPC 3·97% [95% CI 2·44–5·52]), Chile (3·96% [1·26–6·74]), Puerto Rico (3·81% [2·68–4·96]), and England (3·59% [3·12–4·06]). 14 of the 27 countries and territories showed either stable (Argentina, France, Ireland, Norway, and Puerto Rico) or decreasing (Australia, Canada, Germany, Israel, New Zealand, Slovenia, England, Scotland, and the USA) trends in older adults. For the 13 countries with increasing trends in both age groups, the average annual percentage increase in younger compared to older adults was higher in Chile, Japan, Sweden, the Netherlands, Croatia, and Finland; lower in Thailand, France (Martinique), Denmark, and Costa Rica; and similar in Türkiye, Ecuador, and Belarus. The rise in early-onset colorectal cancer was faster among men than women in Chile, Puerto Rico, Argentina, Ecuador, Thailand, Sweden, Israel, and Croatia, whereas faster increase among women compared to men was in England, Norway, Australia, Türkiye, Costa Rica, and Scotland.

Interpretation

Early-onset colorectal cancer incidence rates are rising in 27 of 50 countries and territories examined, with the rise either exclusive to early-onset disease or faster than the increase in older adults in 20 of the 27 countries. The findings underscore the need for intensified efforts to identify factors driving these trends and increase awareness to help facilitate early detection.

Funding

Intramural Research Program of the American Cancer Society, Cancer Grand Challenges, and National Institutes of Health.

中文翻译：

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年轻人与老年人的结直肠癌发病率趋势：基于人群的癌症登记数据分析

 背景

先前的研究表明，在多个高收入西方国家，年轻人 （年龄 <50 岁） 的结直肠癌发病率正在增加，而老年人 （≥50 岁） 的发病率呈稳定或下降趋势。本研究旨在调查年轻人与老年人的当代结直肠癌发病率趋势。

 方法

结直肠癌发病率数据，包括 50 个国家和地区的诊断年份、性别和 5 岁年龄组，均从 WHO–International Agency for Research on Cancer Incidence in Five continents Plus 数据库中提取。2022 年人类发展指数取自联合国开发计划署，分为非常高 （>0·80）、高 （0·70–0·79）、中 （0·55–0·69） 和低 （<0·55） 类别。1943-2003 年和 2015-17 年诊断的早发性（诊断年龄在 25 至 49 岁之间）和晚发性（诊断年龄在 50 至 74 岁之间）结直肠癌（ICD 第 10 次修订版，C18-20）的年龄标准化发病率 （ASR），使用直接方法和 Segi-Doll 世界标准人群计算。主要研究目的是使用截至 2017 年来自 50 个国家和地区的数据来检查年轻人与老年人的当代结直肠癌发病率趋势。通过连接点回归可视化和量化时间趋势，按诊断年龄（25-49 岁或 50-74 岁）分层。估计平均年百分比变化 （AAPC）。

 发现

在最近 5 年（除日本 [2011-15]、西班牙 [2012-16] 和哥斯达黎加 [2012-16] 外，所有分析国家均为 2013-17 年），早发性结直肠癌的发病率最高：澳大利亚 （ASR 16·5 [95% CI 16·1–16·9]）、美国（波多黎各;15·2 [14·2–16·2]）、新西兰 （14·8 [14·0–15·6]）、 美国 （14·8 [14·7–14·9]） 和韩国 （14·3 [14·0–14·5]），乌干达 （4·4 [3·6–5·2]） 和印度 （3·5 [3·3–3·7]） 最低。荷兰 （168·4 [166·9–170·0]） 和丹麦 （158·3 [155·8–160·9]） 老年人发病率最高，乌干达 （45·9 [38·5–51·4]） 和印度 （23·5 [22·8–24·3]） 最低。就 AAPC 而言，在过去 10 年中，23 个国家的早发性结直肠癌发病率保持稳定，但在 27 个国家/地区有所增加，其中新西兰 （AAPC 3·97% [95% CI 2·44–5·52]）、智利 （3·96% [1·26–6·74]）、波多黎各 （3·81% [2·68–4·96]）、 和英格兰 （3·59% [3·12–4·06]）。在 27 个国家和地区中，有 14 个国家和地区的老年人呈稳定（阿根廷、法国、爱尔兰、挪威和波多黎各）或下降（澳大利亚、加拿大、德国、以色列、新西兰、斯洛文尼亚、英格兰、苏格兰和美国）趋势。在两个年龄组均呈上升趋势的 13 个国家中，智利、日本、瑞典、荷兰、克罗地亚和芬兰的年轻人与老年人相比的年平均百分比增长更高;泰国、法国（马提尼克岛）、丹麦和哥斯达黎加的产量较低;土耳其、厄瓜多尔和白俄罗斯也有类似的情况。 在智利、波多黎各、阿根廷、厄瓜多尔、泰国、瑞典、以色列和克罗地亚，男性早发性结直肠癌的增加速度快于女性，而在英格兰、挪威、澳大利亚、土耳其、哥斯达黎加和苏格兰，女性比男性增长更快。

 解释

在接受调查的 50 个国家和地区中，有 27 个国家和地区的早发性结直肠癌发病率正在上升，其中 27 个国家/地区的上升速度要么是早发性疾病独有的，要么高于 27 个国家/地区中 20 个国家/地区的老年人增幅。研究结果强调，需要加大努力，确定驱动这些趋势的因素，并提高认识，以帮助促进早期发现。

 资金

美国癌症协会的校内研究计划、癌症大挑战和美国国立卫生研究院。