Location of rectal cancer as determined using rectal magnetic resonance imaging, and its relationship with pulmonary metastasis

Abstract

Background/Aims: The aim of this study was to evaluate the accuracy of 3-T magnetic resonance imaging (MRI) in locating rectal cancer, and to determine whether tumor location correlates with the incidence of pulmonary metastasis. Materials and Methods: A total of 146 patients with confirmed rectal adenocarcinoma underwent 3-T rectal MRI, and abdominal and chest computed tomography (CT) within 2 weeks of the endoscopic examination. We reviewed the distance between the mass and the anal verge recorded in the endoscopic reports of these patients. Two radiologists evaluated the same distance on MRI scans by using picture archiving and communications systems. Multiple factors including the tumor location, primary tumor and lymph node stage, lung and liver metastasis, pathologic differentiation, and the carcinoembryonic antigen level were evaluated. The correlation between tumor location on MRI and endoscopy was assessed, and significant factors influencing pulmonary metastasis were identified using multivariate logistic regression analysis. Results: There was a statistically significant correlation between the tumor location established using MRI and the actual location recorded during endoscopy. The incidence of pulmonary metastasis was significantly higher in patients with lower rectal cancer (11/17, 65%) compared to those with upper rectal cancer (6/17, 35%; p<0.05). Factors associated with pulmonary metastasis were tumor location and the presence of liver metastasis. Conclusion: The accurate tumor location could be indicated using 3-T rectal MRI. Pulmonary metastasis occurred more frequently in patients with lower rectal cancer than in those with upper rectal cancer.

How to accurately measure the distance from the anal verge to rectal cancer on MRI: a prospective study using anal verge markers

“…The direct methods achieved the least bias, the highest precision, and the best correlation with rigid sigmoidoscopy among the three methods groups. The majority of previous studies have measured the tumor distance using multiple lines that reflect the anorectal curvature [2,6,[18][19][20][21][22][23][24]29]. However, in our study, the direct methods using a straight line demonstrated the best results; this corroborates the findings by Meylemans et al, who compared measurement methods using a straight line or multiple straight lines [19].…”

“…In the recent study, different methods were used to measure the tumor distance from the anal verge on sagittal MRI. Although the majority of research groups have used multiple straight lines from the anal verge along [6,18,19] or not along [2,[20][21][22][23][24] the anorectal centerline, others have used a single straight line [19,25]. Thus, there is no clear consensus on the measurement of tumor distance, and no prospective study has compared these methods.…”

A relationship to survival is seen by combining the factors of mismatch repair status, tumor location and age of onset in colorectal cancer patients

“…It is likely that these different origins of colon tissue could contribute to CRC disease pathology by independent processes. Indeed, there is already evidence to indicate that the clinical characteristics and molecular profiles of gene and protein expression for CRC differ across these different tissue sites[ 21 , 22 , 23 , 24 ]. One previous study has already shown that the primary tumor location could serve as prognostic factor in metastatic CRC[ 25 ].…”

Does a Standardized Distance Cut-off Accurately Predict the Length of the Rectum? Using MRI to Analyze the Height of the Peritoneal Reflection

“…16 Universal standardization of rectal cancer MRI protocols and MRI reporting would greatly benefit the surgical community by facilitating a more effective exchange of knowledge between specialties. 17,18 Another limitation of our study included difficulty defining the true anal verge on MRI. Even amongs radiologic societies, identification of the anal verge on MRI is a controversial topic.…”