From ICES Queen's (P.A.G., C.M., D.S., A.M.) and Division of Cancer Care and Epidemiology, Cancer Research Institute (P.A.G.), Queen's University, Kingston; Ottawa Hospital Research Institute (C.W.); Bruyère Research Institute (C.W.), Ottawa; ICES (C.J.M.), Toronto; Schools of Pharmacy and Public Health & Health Systems (C.J.M.), University of Waterloo; Departments of Psychiatry and Community Health Sciences (D.S.), Cumming School of Medicine, University of Calgary; and Department of Community Health Sciences (A.M., R.A.M.), Manitoba Centre for Health Policy (A.M.), and Department of Internal Medicine (R.A.M.), Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada.
Neurology. 2022 May 3;98(18):e1798-e1809. doi: 10.1212/WNL.0000000000200163.
The multiple sclerosis (MS) population's survival from breast cancer and colorectal cancer is compromised. Cancer screening and timely diagnoses affect cancer survival and have not been studied in the MS cancer population. We investigated whether the diagnostic route, cancer stage, or diagnostic interval differed in patients with cancer with and without MS.
We conducted a matched population-based cross-sectional study of breast cancers (2007-2015) and colorectal cancers (2009-2012) in patients with MS from Ontario, Canada, using administrative data. Exclusion criteria included second or concurrent primary cancers, no health care coverage, and, for the patients without MS, those with any demyelinating disease. We based 1:4 matching of MS to non-MS on birth year, sex (colorectal only), postal code, and cancer diagnosis year (breast only). Cancer outcomes were diagnostic route (screen-detected vs symptomatic), stage (stage I vs all others), and diagnostic interval (time from first presentation to diagnosis). Multivariable regression analyses controlled for age, sex (colorectal only), diagnosis year, income quintile, urban/rural residence, and comorbidity.
We included 351 patients with MS and breast cancer, 1,404 matched patients with breast cancer without MS, 54 patients with MS and colorectal cancer, and 216 matched patients with colorectal cancer without MS. MS was associated with fewer screen-detected cancers in breast (odds ratio [OR] 0.68 [95% CI 0.52, 0.88]) and possibly colorectal (0.52 [0.21, 1.28]) cancer. MS was not associated with differences in breast cancer stage at diagnosis (stage I cancer, OR 0.81 [0.64, 1.04]). MS was associated with greater odds of stage I colorectal cancer (OR 2.11 [1.03, 4.30]). The median length of the diagnostic interval did not vary between people with and without MS in either the breast or colorectal cancer cohorts. Controlling for disability status attenuated some findings.
Breast cancers were less likely to be detected through screening and colorectal cancer more likely to be detected at early stage in people with MS than without MS. MS-related disability may prevent people from getting mammograms and colonoscopies. Understanding the pathways to earlier detection in both cancers is critical to developing and planning interventions to ameliorate outcomes for people with MS and cancer.
多发性硬化症（MS）患者的乳腺癌和结直肠癌生存率受损。癌症筛查和及时诊断会影响癌症的生存率，但其在 MS 癌症患者中的研究尚未进行。我们调查了 MS 患者与非 MS 患者的癌症诊断途径、癌症分期和诊断间隔是否存在差异。
我们使用行政数据，对加拿大安大略省的 MS 患者进行了一项基于人群的乳腺癌（2007-2015 年）和结直肠癌（2009-2012 年）的匹配病例对照横断面研究。排除标准包括第二原发癌或同时性原发癌、无医疗保健覆盖和（对于非 MS 患者）任何脱髓鞘疾病。我们基于出生年份、性别（仅结直肠）、邮政编码和癌症诊断年份（仅乳腺癌），对 MS 患者与非 MS 患者进行了 1:4 匹配。癌症结局包括诊断途径（筛查发现与症状性）、分期（I 期与其他所有分期）和诊断间隔（从首次就诊到诊断的时间）。多变量回归分析控制了年龄、性别（仅结直肠）、诊断年份、收入五分位数、城乡居住和合并症。
我们纳入了 351 例 MS 合并乳腺癌患者、1404 例匹配的非 MS 乳腺癌患者、54 例 MS 合并结直肠癌患者和 216 例匹配的非 MS 结直肠癌患者。MS 与乳腺癌中筛查发现的癌症（比值比 [OR] 0.68 [95% CI 0.52, 0.88]）和可能的结直肠癌（0.52 [0.21, 1.28]）减少有关。MS 与乳腺癌诊断时的分期无差异（I 期癌症，OR 0.81 [0.64, 1.04]）。MS 与结直肠癌 I 期的几率增加有关（OR 2.11 [1.03, 4.30]）。在乳腺癌或结直肠癌队列中，无论有无 MS，诊断间隔的中位数长度均无差异。控制残疾状况会削弱部分发现。
MS 患者的乳腺癌筛查检出率较低，结直肠癌更可能在早期发现。MS 相关残疾可能会阻止人们进行乳房 X 线摄影和结肠镜检查。了解这两种癌症中更早发现的途径对于制定和规划干预措施以改善 MS 患者的癌症结局至关重要。
