近日，英国牛津大学Brian D Nicholson课题组对初级保健中意外减重者的患癌风险进行了研究。2020年8月13日，该研究发表在《英国医学杂志》上。
为了根据患者的年龄、性别、吸烟状况以及临床特征（症状、体征和血液检查结果异常）来量化癌症意外体重减轻（减重）的预测价值，研究组使用英格兰初级保健的国家癌症注册和分析服务数据，进行了一项诊断准确性研究。
2000年1月1日至2012年12月31日，共有63973名成年人（≥18岁）意外减重，其中女性37215名（58.2%），年龄在60岁以上的女性为33167名（51.8%），吸烟者为16793名（26.3%）。入组后六个月内，908名（1.4%）参与者被诊断出癌症，其中882名（97.1%）年龄在50岁以上。对年龄在50岁及以上的男性吸烟者进行紧急检查，发现其癌症阳性预测值高于英国国家健康与护理卓越研究所推荐的3%阈值，但全年龄的女性中则没有。
意外减重的男性中有10个其他临床特征与癌症相关，女性中则有11个与癌症相关。男性的阳性似然比范围从非心脏性胸痛的1.86到腹部肿块的6.10不等，女性则从背痛的1.62到黄疸的20.9不等。与癌症相关的血液检查结果异常包括低白蛋白水平，血小板值、钙、白细胞总数和C反应蛋白升高。但一般血液检查结果并不能排除癌症。意外减重并发的临床特征与多个癌症部位相关。
总之，在初级保健中出现意外减重的成年人患癌症的风险低于2％，因此不值得根据当前的英国指南进行检查。但对于年龄在50岁及以上的男性吸烟者，以及同时存在临床特征的患者，其癌症风险值得转诊并进行侵入性检查。
附：英文原文
Title: Prioritising primary care patients with unexpected weight loss for cancer investigation: diagnostic accuracy study
Author: Brian D Nicholson, Paul Aveyard, Sarah J Price, FD Richard Hobbs, Constantinos Koshiaris, Willie Hamilton
Issue&Volume: 2020/08/13
Abstract: Objective To quantify the predictive value of unexpected weight loss (WL) for cancer according to patient’s age, sex, smoking status, and concurrent clinical features (symptoms, signs, and abnormal blood test results).
Design Diagnostic accuracy study.
Setting Clinical Practice Research Datalink electronic health records data linked to the National Cancer Registration and Analysis Service in primary care, England.
Participants 63973 adults (≥18 years) with a code for unexpected WL from 1 January 2000 to 31 December 2012.
Main outcome measures Cancer diagnosis in the six months after the earliest weight loss code (index date). Codes for additional clinical features were identified in the three months before to one month after the index date. Diagnostic accuracy measures included positive and negative likelihood ratios, positive predictive values, and diagnostic odds ratios.
Results Of 63973 adults with unexpected WL, 37215 (58.2%) were women, 33167 (51.8%) were aged 60 years or older, and 16793 (26.3%) were ever smokers. 908 (1.4%) had a diagnosis of cancer within six months of the index date, of whom 882 (97.1%) were aged 50 years or older. The positive predictive value for cancer was above the 3% threshold recommended by the National Institute for Health and Care Excellence for urgent investigation in male ever smokers aged 50 years or older, but not in women at any age. 10 additional clinical features were associated with cancer in men with unexpected WL, and 11 in women. Positive likelihood ratios in men ranged from 1.86 (95% confidence interval 1.32 to 2.62) for non-cardiac chest pain to 6.10 (3.44 to 10.79) for abdominal mass, and in women from 1.62 (1.15 to 2.29) for back pain to 20.9 (10.7 to 40.9) for jaundice. Abnormal blood test results associated with cancer included low albumin levels (4.67, 4.14 to 5.27) and raised values for platelets (4.57, 3.88 to 5.38), calcium (4.28, 3.05 to 6.02), total white cell count (3.76, 3.30 to 4.28), and C reactive protein (3.59, 3.31 to 3.89). However, no normal blood test result in isolation ruled out cancer. Clinical features co-occurring with unexpected WL were associated with multiple cancer sites.
Conclusion The risk of cancer in adults with unexpected WL presenting to primary care is 2% or less and does not merit investigation under current UK guidelines. However, in male ever smokers aged 50 years or older and in patients with concurrent clinical features, the risk of cancer warrants referral for invasive investigation. Clinical features typically associated with specific cancer sites are markers of several cancer types when they occur with unexpected WL.
DOI: 10.1136/bmj.m2651
Source: https://www.bmj.com/content/370/bmj.m2651
BMJ-British Medical Journal:《英国医学杂志》，创刊于1840年。隶属于BMJ出版集团，最新IF：93.333
官方网址：http://www.bmj.com/
投稿链接：https://mc.manuscriptcentral.com/bmj
本期文章：《英国医学杂志》：Online/在线发表
