La biopsie transrectale sous échographie endorectale des ganglions du mésorectum est-elle un examen de certitude lors du bilan d'extension locorégional des cancers du rectum ? Rapport d'un cas de faux-positif

The authors report a case of false-positive ultrasound-guided fine needle aspiration in the initial staging of a rectal cancer. A 46 year-old patient presented with a middle third tumor of the rectum staged T2-T3 by MRI and endorectal ultrasonography. Ultrasound-guided fine needle aspiration of mesorectal nodes showed adenocarcinomatous cells. A subtotal proctectomy was performed without neoadjuvant treatment. Histological report showed a well differentiated adenocarcinoma pT2pN0 (42 examined lymph nodes). The authors discuss the different hypothesis to explain the discordance between preoperative staging and definitive histological results.