Utility of reassessment after neoadjuvant therapy and difficulties in interpretation.
We describe the main tools for MR assessment of the response of rectal cancer tumors after chemotherapy, before surgery. In locally advanced cases of rectal and lower rectal cancer, MR is useful in allowing the treatment strategy to be adjusted, enabling conservative surgery to be performed if the patient responds well. The different types of response (fibrous, desmoplastic and colloid), their appearances and difficulties in MR interpretation are described. We describe the features and performance of MR after neoadjuvant therapy for T and N staging, assessment of circumferential resection margin and diffusion weighted imaging. Quantitative (change in tumor volume) and qualitative (grade of tumor response) MR assessment can distinguish good responders from poor responders.
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France. Electronic address: ma-pierredon_foulongne@chu-montpellier.fr.
M-A
MA
Pierredon-Foulongne
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
S
S
Nougaret
Department of Pathological Anatomy, Montpellier Regional Cancer Institute, 208, avenue des Apothicaires, 34298 Montpellier cedex 5, France.
F
F
Bibeau
Department of Surgery, Montpellier Regional Cancer Institute, 208, avenue des Apothicaires, 34298 Montpellier cedex 5, France.
P
P
Rouanet
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
E
E
Delhom
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
J
J
Lonjon
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
N
N
Ragu
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
J
J
Colleau
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
V
V
Schembri
Department of Diagnostic and Interventional Radiology, Dijon University Hospitals, 1, boulevard Jeanne-d'Arc, 21079 Dijon, France.
B
B
Guiu
Department of Medical Imaging, Saint-Eloi Hospital, Montpellier University Hospitals, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France.
B
B
Gallix
D002288:Adenocarcinoma, Mucinous / Q000473:pathology / Q000628:therapy; D059186:Chemoradiotherapy, Adjuvant; D003131:Combined Modality Therapy; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020360:Neoadjuvant Therapy; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology / Q000628:therapy*; D012007:Rectum / Q000473:pathology / Q000601:surgery; D047368:Tumor Burden / Q000187:drug effects / Q000502:physiology
Cancer; MR; Neoadjuvant therapy; Rectum; Response