1. Diagnosis of Clinical Complete Response by Probe-Based Confocal Laser Endomicroscopy (pCLE) After Chemoradiation for Advanced Rectal Cancer
- Author
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Ulysses Ribeiro, Clelma Batista Pires, Luciana Regina Meirelles, Lívia Arraes, Elisa Ryoka Baba, Carla Cristina Gusmon-Oliveira, Bruno da Costa Martins, Fábio Shigehissa Kawaguti, Luciano Tolentino Lenz, Carlos Frederico Sparapan Marques, Sergio Carlos Nahas, Adriana V. Safatle-Ribeiro, Marcelo Simas de Lima, and Fauze Maluf-Filho
- Subjects
Male ,medicine.medical_specialty ,Colorectal cancer ,Locally advanced ,Malignancy ,03 medical and health sciences ,0302 clinical medicine ,Clinical complete response ,medicine ,Rectal Adenocarcinoma ,Humans ,Radical surgery ,Confocal laser endomicroscopy ,Microscopy, Confocal ,business.industry ,Rectal Neoplasms ,Lasers ,Gastroenterology ,Rectum ,Chemoradiotherapy ,Middle Aged ,medicine.disease ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Surgery ,Radiology ,business ,Neoadjuvant chemoradiotherapy - Abstract
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.
- Published
- 2020