Author(s): Santiago, Inês ; Rodrigues, Bernardete ; Barata, Maria ; Figueiredo, Nuno ; Fernandez, Laura ; Galzerano, Antonio ; Parés, Oriol ; Matos, Celso
Date: 2021
Persistent ID: http://hdl.handle.net/10362/124275
Origin: Repositório Institucional da UNL
Subject(s): Magnetic resonance imaging; Neoadjuvant therapy; Re-staging; Rectal cancer; “Watch-and-Wait”; Radiology Nuclear Medicine and imaging; SDG 3 - Good Health and Well-being
Funding Information: We are grateful to all staff composing the?Imaging Department, the Colorectal Cancer Unit, and The Pathology Department of the Champalimaud Foundation. We would also like to thank Nuno Lou??o from Philips Healthcare (R) for the outstanding technical support. Publisher Copyright: © 2021, The Author(s).
In the past nearly 20 years, organ-sparing when no apparent viable tumour is present after neoadjuvant therapy has taken an increasingly relevant role in the therapeutic management of locally-advanced rectal cancer patients. The decision to include a patient or not in a “Watch-and-Wait” program relies mainly on endoscopic assessment by skilled surgeons, and MR imaging by experienced radiologists. Strict surveillance using the same modalities is required, given the chance of a local regrowth is of approximately 25–30%, almost always surgically salvageable if caught early. Local regrowths occur at the endoluminal aspect of the primary tumour bed in almost 90% of patients, but the rest are deep within it or outside the rectal wall, in which case detection relies solely on MR Imaging. In this educational review, we provide a practical guide for radiologists who are, or intend to be, involved in the re-staging and follow-up of rectal cancer patients in institutions with an established “Watch-and-Wait” program. First, we discuss patient preparation and MR imaging acquisition technique. Second, we focus on the re-staging MR imaging examination and review the imaging findings that allow us to assess response. Third, we focus on follow-up assessments of patients who defer surgery and confer about the early signs that may indicate a sustained/non-sustained complete response, a rectal/extra-rectal regrowth, and the particular prognosis of the “near-complete” responders. Finally, we discuss our proposed report template.
