Endoscopy Unit, Department of Gastroenterology, Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas, University of São Paulo School of Medicine (ICESP-HCFMUSP), Av. Dr. Enéas Carvalho de Aguiar, 255, Cerqueira Cesar, São Paulo, SP, 05403-000, Brazil.
Digestive Surgery and Colorectal Division, Department of Gastroenterology, Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas, University of São Paulo School of Medicine (ICESP-HCFMUSP), Av. Dr. Enéas Carvalho de Aguiar, 255, Cerqueira Cesar, São Paulo, SP, 05403-000, Brazil.
J Gastrointest Surg. 2021 Feb;25(2):357-368. doi: 10.1007/s11605-020-04878-y. Epub 2021 Jan 14.
Neoadjuvant chemoradiotherapy (nCRxt) followed by radical surgery is the optimal treatment for advanced rectal adenocarcinoma. Patients with clinical complete response (cCR) may be followed closely without immediate surgery. Probe-based confocal laser endomicroscopy (pCLE) is a real-time in vivo method that allows acquisition of optical biopsies with 1000 times magnification, evaluating both epithelial and vascular patterns.
To evaluate the role of pCLE in the diagnosis of cCR after nCRxt for advanced rectal adenocarcinoma.
pCLE was performed in 47 patients with locally advanced rectal adenocarcinoma (T3/T4, or N+) who underwent nCRxt (5-fluorouracil, 5040 cGy).
Twenty-seven (57.5%) patients were men, and the mean age was 62.8 years. Thirty-seven had partial response confirmed by pCLE. Ten (21.3%) patients had good endoscopic response and presented small ulcer (n = 5) or residual scar (n = 5). After nCRxt, the essential features to differentiate malignancy from post-radiation alterations at pCLE were the presence of irregular crypts, budding, back-to-back glands, cribriform pattern, increased vessel/crypt ratio, and fluorescein leakage. A scoring system was created considering these epithelial and vascular features, with high accuracy for differentiating patients with complete response from those with residual neoplasia (p < 0.00001). pCLE sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 100%, 71.4%, 95.2%, 100%, and 95.7%, respectively.
(1) pCLE evaluation of epithelial and vascular features may improve the diagnosis of cCR and may alter patient management; (2) pCLE might be valuable for identifying patients with advanced rectal cancer who will benefit from watch and wait strategy, avoiding immediate surgical treatment.
新辅助放化疗（nCRxt）后行根治性手术是治疗局部晚期直肠腺癌的最佳方法。对于临床完全缓解（cCR）的患者，可密切随访而无需立即手术。探针式共聚焦激光内镜检查（pCLE）是一种实时的体内方法，可通过 1000 倍放大获得光学活检，评估上皮和血管模式。
评估 pCLE 在局部晚期直肠腺癌 nCRxt 后诊断 cCR 的作用。
对 47 例接受 nCRxt（5-氟尿嘧啶，5040 cGy）的局部晚期直肠腺癌（T3/T4，或 N+）患者进行 pCLE 检查。
27 例（57.5%）患者为男性，平均年龄为 62.8 岁。37 例经 pCLE 证实有部分缓解。10 例（21.3%）患者内镜下反应良好，表现为小溃疡（n=5）或残留瘢痕（n=5）。nCRxt 后，pCLE 区分恶性与放疗后改变的基本特征是存在不规则隐窝、芽生、背靠背腺体、筛状模式、血管/隐窝比增加和荧光素渗漏。考虑到这些上皮和血管特征，建立了一种评分系统，用于区分完全缓解和残留肿瘤患者，具有很高的准确性（p<0.00001）。pCLE 的敏感性、特异性、阳性预测值、阴性预测值和准确性分别为 100%、71.4%、95.2%、100%和 95.7%。
（1）pCLE 评估上皮和血管特征可能提高 cCR 的诊断，并可能改变患者的管理策略；（2）pCLE 可能有助于识别从观察和等待策略中获益的局部晚期直肠癌患者，避免立即进行手术治疗。
