Burtin P, Rabot A F, Heresbach D, Carpentier S, Rousselet M C, Le Berre N, Boyer J
University Hospital, Angers, France.
Endoscopy. 1997 Sep;29(7):620-5. doi: 10.1055/s-2007-1004267.
In rectal tumors invasion of the rectal fat and perirectal lymph nodes are generally regarded as independent prognostic factors in most prospective series. There are no studies in the literature concerning interobserver agreement on the staging of rectal cancer by endorectal ultrasonography (EUS). The aim of the present study was to assess interobserver agreement using EUS in the TN staging of rectal cancer.
Thirty-seven patients with rectal cancer were investigated at two centers using EUS as part of the pretherapeutic staging (Olympus EUM-3 or EUM-20). All examinations were videotaped and reviewed six months later by four independent observers who assessed the stage of the tumor (from uT1 to uT4) and lymphatic invasion on a blinded basis. When the tumor was assessed as uT3, the observers specified the degree of involvement of the rectal fat (in millimeters). Interobserver agreement was estimated using the kappa coefficient (k) and the intraclass correlation coefficient (ICC). Agreement was classed as poor (k < 0.40), fair to good (0.40 < or = k < 0.75) or excellent (k < or = 0.75).
Agreement was fair for uT1 tumors (k = 0.40) and poor for uT2 tumors (k = 0.20). Agreement was good (k = 0.58; CI 0.51 to 0.65) for uT3 tumors; there was a significant interobserver correlation for the exact measure of the extent of rectal fat (ICC = 0.65). The agreement was also good (k = 0.54, CI 0.47 to 0.61) for metastatic lymph nodes.
As in the case of esophageal cancer, interobserver agreement on the staging of uT2 tumors is poor with EUS. The evaluation of rectal tumors with a poor prognosis shows good interobserver agreement.
在大多数前瞻性研究系列中，直肠肿瘤侵犯直肠脂肪和直肠周围淋巴结通常被视为独立的预后因素。文献中尚无关于直肠内超声检查（EUS）对直肠癌分期的观察者间一致性的研究。本研究的目的是评估EUS在直肠癌TN分期中的观察者间一致性。
在两个中心对37例直肠癌患者进行了EUS检查，作为治疗前分期的一部分（Olympus EUM - 3或EUM - 20）。所有检查均进行了录像，并在6个月后由4名独立观察者进行回顾，他们在不知情的情况下评估肿瘤分期（从uT1到uT4）和淋巴浸润情况。当肿瘤被评估为uT3时，观察者指定直肠脂肪受累程度（以毫米为单位）。使用kappa系数（k）和组内相关系数（ICC）估计观察者间一致性。一致性分为差（k < 0.40）、中等至良好（0.40≤k < 0.75）或优秀（k≥0.75）。
对于uT1肿瘤，一致性为中等（k = 0.40）；对于uT2肿瘤，一致性较差（k = 0.20）。对于uT3肿瘤，一致性良好（k = 0.58；CI 0.51至0.65）；直肠脂肪受累程度的精确测量存在显著的观察者间相关性（ICC = 0.65）。对于转移性淋巴结，一致性也良好（k = 0.54，CI 0.47至0.61）。
与食管癌一样，EUS对uT2肿瘤分期的观察者间一致性较差。对预后不良的直肠肿瘤的评估显示观察者间一致性良好。
