Brain tumour patients see their primary care doctor on average three or more times before diagnosis, so there may be an opportunity to identify ‘at risk’ patients earlier. Suspecting a brain tumour diagnosis is difficult because brain tumour-related symptoms are typically non-specific. We explored the predictive value of referral guidelines (Kernick and NICE 2005) for brain imaging where a tumour is suspected, in a population-based patient group referred for direct access CT of the head. A consensus panel reviewed whether non-tumour findings were clinically important or whether further investigation was necessary. Over a 5-year period, 3257 head scans were performed; 318 scans were excluded according to pre-specified criteria. 53 patients (1.8%) were reported to have intracranial tumours, of which 42 were significant (diagnostic yield of 1.43%). There were no false negative CT scans for tumour. With symptom-based referral guidelines primary care doctors can identify patients with a 3% positive predictive value (PPV). 559 patients had non-tumour findings, 31% of which were deemed clinically significant. In 34% of these 559 patients, referral for further imaging and/or specialist assessment from primary care was still thought warranted. Existing referral guidelines are insufficient to stratify patients adequately based on their symptoms, according to the likelihood that a tumour will be found on brain imaging. Identification of non-tumour findings may be significant for patients and earlier specialist input into interpretation of these images may be beneficial. Improving guidelines to better identify patients at risk of a brain tumour should be a priority, to improve speed of diagnosis, and reduce unnecessary imaging and costs. Future guidelines may incorporate groups of symptoms, clinical signs and tests to improve the predictive value.

中文翻译：

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直接进入CT怀疑脑瘤：基于人群的患者群体中的转诊途径分析

脑肿瘤患者在诊断前平均要看三遍或三遍以上的初级保健医生，因此可能有机会及早发现“高危”患者。怀疑脑肿瘤诊断很困难，因为与脑肿瘤相关的症状通常是非特异性的。我们探讨了在可能被怀疑患有肿瘤的人群中，推荐用于头部直接CT扫描的人群指南中的转诊指南（Kernick and NICE 2005）的预测价值。共识小组审查了非肿瘤发现在临床上是否重要或是否需要进一步研究。在5年的时间里，进行了3​​257次头部扫描。根据预先指定的标准，排除了318次扫描。据报道53例（1.8％）患有颅内肿瘤，其中42例显着（诊断率为1.43％）。没有虚假的CT扫描阴性肿瘤。通过基于症状的转诊指南，初级保健医生可以识别出阳性预测值（PPV）为3％的患者。559例患者无肿瘤发现，其中31％被认为具有临床意义。在这559名患者中，有34％仍被认为有必要从初级保健中转诊以进行进一步的成像和/或专家评估。根据在脑成像中发现肿瘤的可能性，现有的转诊指南不足以根据患者的症状对患者进行充分分层。非肿瘤发现的识别对患者可能很重要，而早期专家对这些图像的解释可能会有所帮助。改善指南以更好地识别有脑瘤风险的患者应该成为优先事项，以提高诊断速度，并减少不必要的成像和成本。未来的指南可能会结合各种症状，临床体征和测试，以提高预测价值。