Rectal adenocarcinoma is a common malignancy with high mortality and morbidity .Over the past few years, significant progress has been made in the management of rectal cancer with advances in both surgical technique and adjuvant therapies. Several studies have been published showing the ability of MRI to accurately stage rectal cancer and to identify the relevant anatomy. Many studies have shown good agreement between MRI findings and both surgical and histopathological findings. MRI allows proper preoperative tumor staging by assessment of the tumor itself, nodal spread and depth of tumor invasion which allows the triage of patients to up-front surgical resection or neoadjuvant therapy. Our work included 40 patients presented with rectal carcinoma with age ranging between 25 and 90 years with the aim to evaluate the role of MRI in staging of preoperative cases of rectal cancer. All patients in this study were imaged using 1.5T superconducting magnet MRI machines and the assessment of tumours was carried including its location , distance from  sphincter complex, degree of extramural spread, T stage, N stage, relation to peritoneal reflections, and relations to pelvic viscera and the presence of extramural vascular invasion. MRI proved very useful and accurate in assessment of all these factors which enabled accurate patient staging and aided in the choice of therapy.

Keywords: APR: anterior peritoneal reflection. CRM: circumferential resection margin, MRF: mesorectal fascia, EMVI: extramural vascular invasion. TSE: turbo spin echo. TME: total mesorectal excision.

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Bassant Hasan Shaaban Mohammed

Department of Radiology, Faculty of Medicine for girls, Al-Azhar University