COVID-19大流行期间对医疗保健的干扰可能导致癌症诊断的漏诊。评估COVID-19大流行与癌症发病之间的关联至关重要，以解决公众和患者的焦虑，为恢复工作提供信息，并确定减少系统脆弱性的策略。为调查COVID-19大流行与加拿大曼尼托巴省的癌症发病率之间的关联，我们进行了一项基于人群的横断面研究设计，使用了曼尼托巴省癌症登记处和中断时间序列分析的数据。纳入了加拿大曼尼托巴省2015年1月1日至2021年12月31日期间被诊断为癌症的所有个体。根据年龄将被诊断为乳腺癌、结肠癌、直肠癌或肺癌的个体分为以下组别：年龄小于50岁、50至74岁和75岁及以上。COVID-19大流行期间。按年龄标准化的癌症发病率和在没有COVID-19的情况下与观察到（拟合）的癌症病例数间的估计累积差异。共纳入了48,378名个体。诊断时的中位数（IQR）年龄为68（59-77）岁，23,972名参与者（49.6%）为女性。2020年4月，整体癌症发病率下降了23%。乳腺癌发病率下降了46%，结肠癌发病率下降了35%，直肠癌发病率下降了47%，头颈部癌症发病率下降了50%，黑色素瘤发病率下降了65%，内分泌癌症发病率下降了33%，血液学癌症诊断上升12%，原发部位未知癌症诊断上升8%。肺癌发病率一直稳定，直到2020年12月下降了11%。脑和中枢神经系统以及泌尿系统癌症诊断从2020年4月到2021年12月持续下降，分别下降了26%和12%。未观察到与妇科癌症（1%增加），其他消化道癌症（1%减少）或胰腺癌症（7%增加）发病率的关联。截至2021年12月，曼尼托巴省估计缺口为692例（5.3%）。乳腺癌（273例，14.1%缺口）、结肠癌（133例，12.2%缺口）和肺癌（132例，7.6%缺口）的估计缺口最大。本研究发现，COVID-19大流行与大多数癌症部位的发病率最初下降，然后恢复。然而，对于一些具有较高致死率的癌症，累积缺口需要立即关注。

Disruptions to health care during the COVID-19 pandemic may have led to missed cancer diagnoses. It is critical to evaluate the association between the COVID-19 pandemic and cancer incidence to address public and patient anxiety, inform recovery efforts, and identify strategies to reduce the system's vulnerability to future disruptions.To examine the association between the COVID-19 pandemic and cancer incidence in Manitoba, Canada.A population-based cross-sectional study design was conducted using data from the Manitoba Cancer Registry and an interrupted time-series analysis. All individuals diagnosed with cancer in Manitoba, Canada, from January 1, 2015, until December 31, 2021, were included. Individuals diagnosed with breast, colon, rectal, or lung cancer were grouped by age as follows: younger than 50 years, 50 to 74 years, and 75 years and older.COVID-19 pandemic.Age-standardized cancer incidence rates and the estimated cumulative difference between the number of cases in the absence of COVID-19 and observed (fitted) number of cancer cases.A total of 48 378 individuals were included. The median (IQR) age at diagnosis was 68 (59-77) years and 23 972 participants (49.6%) were female. In April 2020, there was a 23% decrease in overall cancer incidence. Cancer incidence decreased by 46% for breast, 35% for colon, 47% for rectal, 50% for head and neck, 65% for melanoma, and 33% for endocrine cancer diagnoses and increased by 12% for hematological cancer diagnoses and 8% for diagnoses of cancers with an unknown primary site. Lung cancer incidence remained stable until December 2020 when it decreased by 11%. Brain and central nervous system and urinary cancer diagnoses decreased consistently over time from April 2020 to December 2021 by 26% and 12%, respectively. No association was observed with gynecologic (1% increase), other digestive (1% decrease), or pancreatic (7% increase) cancer incidence. As of December 2021, Manitoba had an estimated deficit of 692 (5.3%) cancers. The largest estimated deficits were for breast (273 cases, 14.1% deficit), colon (133 cases, 12.2% deficit), and lung cancers (132 cases, 7.6% deficit).In this study, the COVID-19 pandemic was associated with an initial decrease in cancer diagnosis incidence followed by a recovery for most cancer sites. However, the cumulative deficit for some cancers with high fatality needs immediate attention.