title: Endorectal ultrasound and magnetic resonance imaging in rectal cancer staging.
abstract: The majority of rectal cancers have local disease only at presentation, but despite meticulous surgery, a number of factors will influence outcome. Preoperative identification of adverse prognostic factors provides a rational basis for selecting preoperative therapy. Thin section MRI can influence preoperative therapeutic algorithms by T and N staging, demonstrating operability, and the potential risk of circumferential margin involvement. Endosonography may contribute to this, but has a greater role in determining intramural invasion for early tumors. The assessment of residual tumor after chemoradiotherapy remains difficult; PET scanning has been used in this situation [32], but has not been compared with MRI and is unlikely to show only residual cells with extensive fibrosis.
authors.affiliation: Imperial College School of Medicine and St. Mark's Hospital, Northwick Park, Harrow HA1 3UJ, UK. c.bartram@ic.ac.uk
authors.forename: Clive
authors.initials: C
authors.lastname: Bartram
authors.forename: Gina
authors.initials: G
authors.lastname: Brown
mesh_terms: D019160:Endosonography; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D011379:Prognosis; D012004:Rectal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000628:therapy