Topic Highlight
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Feb 21, 2011; 17(7): 828-834
Published online Feb 21, 2011. doi: 10.3748/wjg.v17.i7.828
Current trends in staging rectal cancer
Abdus Samee, Chelliah Ramachandran Selvasekar
Abdus Samee, Department of Surgery, Princess Royal Hospital, Telford, Shropshire, United Kingdom
Chelliah Ramachandran Selvasekar, Department of Surgery, Mid Cheshire Hospitals NHS Foundation Trust, Crewe, United Kingdom
Author contributions: Selvasekar CR designed the study; Samee A and Selvasekar CR were literature search and drafting the article; Samee A and Selvasekar CR revised the critically.
Correspondence to: Chelliah Ramachandran Selvasekar, MD, FRCS, Consultant Colorectal Surgeon, Department of Surgery, Mid Cheshire Hospitals NHS Foundation Trust, Crewe, United Kingdom.
Telephone: +44-1270-612046 Fax: +44-1270-612494
Received: August 30, 2010
Revised: November 12, 2010
Accepted: November 19, 2010
Published online: February 21, 2011

Management of rectal cancer has evolved over the years. In this condition preoperative investigations assist in deciding the optimal treatment. The relation of the tumor edge to the circumferential margin (CRM) is an important factor in deciding the need for neoadjuvant treatment and determines the prognosis. Those with threatened or involved margins are offered long course chemoradiation to enable R0 surgical resection. Endoanal ultrasound (EUS) is useful for tumor (T) staging; hence EUS is a useful imaging modality for early rectal cancer. Magnetic resonance imaging (MRI) is useful for assessing the mesorectum and the mesorectal fascia which has useful prognostic significance and for early identification of local recurrence. Computerized tomography (CT) of the chest, abdomen and pelvis is used to rule out distant metastasis. Identification of the malignant nodes using EUS, CT and MRI is based on the size, morphology and internal characteristics but has drawbacks. Most of the common imaging techniques are suboptimal for imaging following chemoradiation as they struggle to differentiate fibrotic changes and tumor. In this situation, EUS and MRI may provide complementary information to decide further treatment. Functional imaging using positron emission tomography (PET) is useful, particularly PET/CT fusion scans to identify areas of the functionally hot spots. In the current state, imaging has enabled the multidisciplinary team of surgeons, oncologists, radiologists and pathologists to decide on the patient centered management of rectal cancer. In future, functional imaging may play an active role in identifying patients with lymph node metastasis and those with residual and recurrent disease following neoadjuvant chemoradiotherapy.

Keywords: Rectal cancer, Staging, Investigations, Magnetic resonance imaging, Ultrasound, Endoanal ultrasound, Positron emission tomography, Computerized tomography