直肠癌新辅助放化疗前后的磁共振检查评估误区

Evaluation pitfalls of magnetic resonance imaging on rectal cancer before and after neoadju-vant chemoradiotherapy

磁共振成像(MRI)检查由于良好的软组织分辨力,已成为直肠癌的首选影像学检查方法,用于明确肿瘤位置、TNM分期、直肠系膜筋膜状态、直肠壁外血管侵犯、有无腹膜返折受累等与治疗及预后相关的重要因素,临床医师可以根据这些因素为直肠癌患者制订手术计划并判断是否需要接受新辅助治疗。对于接受新辅助治疗的直肠癌患者需要在治疗结束后再次行MRI检查,以制订后续治疗策略。笔者回顾总结MRI检查在直肠癌初次分期和新辅助放化疗后的再分期时存在的限制和误区,以期让影像医师及临床医师充分了解直肠癌MRI检查的优势和局限性,进而更好地应用MRI检查辅助制订直肠癌的临床诊断与治疗策略。

Magnetic resonance imaging(MRI)has been the first choice for rectal cancer due to its superb soft tissue resolution.MRI can be used to identify important factors related to treatment and prognosis,including the tumor location,TNM staging,the status of mesorectal fascia,presence of extramural vascular invasion,and involvement of the peritoneal reflection.Clinicians can make optimal surgical planning and determine the need for neoadjuvant therapy according to these factors.Patients who received neoadjuvant therapy need to undergo MRI examination after the completion of therapy with the aim of determining subsequent treatment strategies.The authors review relevant literatures,summarize the limitations and misconceptions of MRI examination in the initial staging of rectal cancer and the re-staging after neoadjuvant chemoradiotherapy,with the aim of enabling imaging physicians and clinical physicians to fully understand the advantages and limitations of MRI examination for rectal cancer,and applying MRI examination to assist in formulating clinical diagnosis and treatment strategies for rectal cancer.