The importance of rectal cancer MRI protocols on iInterpretation accuracy

Abstract

Background: Magnetic resonance imaging (MRI) is used for preoperative local staging in patients with rectal cancer. Our aim was to retrospectively study the effects of the imaging protocol on the staging accuracy.

Endoscopic ultrasound and magnetic resonance imaging forre-staging rectal cancer after radiotherapy

“…After RT-CT, EUS and MRI might be useful to demonstrate tumor shrinkage and down-staging in responsive tumors, which might occasionally disappear completely [17,18,[20][21][22][23] . Increasing reflectivity and signal changes indicate fibrosis, but unless significant tumor bulk remains, neither modality seems to be able to exclude the persistence of tumor cells within fibrosis [24][25][26][27][28] . Finally, EUS-FNA (endoscopic ultrasound-guided fine-needle aspiration) was proposed for N staging of rectal cancer following neoadjuvant chemoradiation [29] .…”

The ability of phased-array MRI in preoperative staging of primary rectal cancer: correlation with histopathological results

“…When performing TME, knowledge of the relationship of the tumor to the circumferential resection margin (CRM) is important. When the CRM is involved with the tumor, the risk of local recurrence is high (9,(15)(16)(17).Chemoradiation therapy is the standard adjunctive preoperative treatment for patients with a high likelihood of curative resection failure (14,18). According to the recent literature, patients who received preoperative chemoradiation therapy had a lower rate of local recurrence compared to patients who received postoperative chemotherapy and radiation therapy (1,19).…”

“…Spatial resolution has dramatically improved with advances in MRI techniques, such as the use of endorectal and phased-array coils (22,23). Current evidence suggests that MRI is the most accurate technique for predicting tumor stage (24) because it provides an assessment of the local prognostic factors, including the extent of extramural tumor spread, the involvement of the lateral resection margin, the involvement of neighboring organs in the pelvis, the presence of local lymph node metastases, extramural lymphovascular infiltration and peritoneal involvement (9,25,26).The purposes of this study were to evaluate the accuracy of MRI performed with phased-array coil for preoperative local tumor staging in patients with rectal cancer and emphasize the importance of the preoperative differentiation of T2 tumors from T3 so the appropriate treatment plan can be applied. …”

“…When performing TME, knowledge of the relationship of the tumor to the circumferential resection margin (CRM) is important. When the CRM is involved with the tumor, the risk of local recurrence is high (9,(15)(16)(17).…”

Abdomen: Solid Organs

“…This is because both perilesional infl ammation and early extraserosal disease may manifest as perirectal fat stranding (Brown et al 1999 ). This can be further limited by suboptimal scan planes that are not truly perpendicular to the course of the involved segment of the rectum (Suzuki et al 2008 ). Additionally, in the parts of the rectum where there is reduced perirectal fat (anterior wall close to the peritoneal refl ection and distal rectum close to the levator ani sling), extraserosal disease may mean direct invasion to the adjacent structure (peritoneal lining, levator ani complex, prostate, or uterus) and can be diffi cult to diagnose (Fig.…”