Magnetic resonance imaging, or MRI, is one of the tools medical teams can use to diagnose or assess stomach cancer. MRI is often used as a way to assess the stage of the cancer or size or placement of any tumors. The information gained from MRI scans aids in diagnosis as well as assessment and preparation for treatment methods, including surgery.
The benefit of MRI in stomach cancer assessment
Unlike X-rays and PET scans, MRIs don't emit or require any radioactive components, which may make them safer for repetitive scanning and assessment needs.1 Instead, MRIs use magnetic fields to create images of organs and other tissues in the body. Prior to some types of scans, the patient may be required to drink a substance known as a contrast dye, which helps the MRI create highly detailed scans. Contrast dye can also be injected into specific areas when targeted MRIs are being performed.
MRIs are painless for the patient, an important benefit when scans may need to be repeated regularly for ongoing assessment of stomach cancer or to determine whether treatments are working to shrink tumors. The patient typically lies on a table that slides into the imaging machine, and the test can take between 30 and 60 minutes.2 For the average patient, risks associated with MRI procedures are almost nonexistent when all safety protocols are followed.3
Another benefit of MRIs in assessing stomach cancer is the ability to get detailed imaging feedback about tumors and other signs of cancer. MRIs are capable of measuring tumors, which helps medical teams plot the growth or reduction of cancer over time, but they also help surgical teams understand exactly where and how tumors are placed. That ensures teams don't go into operative procedures blind and can plan for many complications in advance, such as when a tumor is positioned in an awkward location or is around a critical organ.
MRIs can also assist in assessment of the health of tissue, helping medical providers determine where healthy tissues end and diseased tissues begin. In some cases, the scans reveal metastases, which is when a primary cancer grows or spreads, resulting in other growths in the body. Because it's safe to conduct whole-body or repeat scans with MRI technology, medical teams are more able to get this type of information quickly and plan for the appropriate levels of treatment.
Accuracy of MRI in assessing stomach cancer
MRI does have a fairly high rate of diagnosing various stomach cancers accurately, but the success rate goes up when MRI is coupled with other diagnostic procedures. For example, in a study of 38 patients known to have gastric cancer, MRI was 86.64 percent accurate in diagnosing the condition. That's a high rate when compared to endoscopic ultrasound (EUS), which had an accuracy rate of 73.68 percent in the same study. However, when researchers combined both MRI and EUS, accuracy rose to 89.47 percent.4
Researchers concluded that while EUS can diagnose early stages of gastric cancer, MRI combined with EUS improves accuracy for N staging, making MRI a particularly useful tool in ongoing and preoperative stomach cancer assessments.
Another study compared the accuracy of MRI and CT in various assessments of stomach cancer, including classification and determining metastases. The study concluded that CT and MRI have the same accuracy at detecting N classification, but CT may be more accurate in detecting T classification. At the same time, the authors determined that MRI was more accurate in detecting metastases.5 This study supports the use of MRI as part of a comprehensive approach to assessing stomach cancer.
A third study looked at the use of MRI in preoperative T staging of gastric cancer. The researchers found MRI to be useful because of its ability to provide specific, accurate images that showed where cancer growth was and the depth of that growth. Researchers noted that MRI results could guide surgical or treatment teams in selecting the right approaches for treatment. The study was conducted in 2014, and the authors did note some limitations of MRI technology at that time, including clinical assessment times as long as 45 minutes and limited scan ranges.6 However, technological development since that time (and currently) continues to support MRI tech evolution to reduce those disadvantages.
The overall safety of MRI technology, along with its accuracy, makes it an important tool in diagnosing and assessing stomach cancer. Patients who are dealing with stomach issues or potential cancers can ask their medical providers about the use of MRI in assessment and treatment planning, particularly if surgical methods are being considered.
1. Cancer.Net Editorial Board. "Stomach Cancer: Diagnosis." Cancer.Net. June 2017. Web. 30 October 2018. <https://www.cancer.net/cancer-types/stomach-cancer/diagnosis>.
2. "MRI for stomach cancer." Cancer Treatment Centers of America. Web. 30 October 2018. <https://www.cancercenter.com/stomach-cancer/mri/>.
3. "Magnetic Resonance Imaging (MRI) - Body." RadiologyInfo.org. Web. 30 October 2018. <https://www.radiologyinfo.org/en/info.cfm?pg=bodymr>.
4. Cui Lei, et. al. "Comparison of MRI and endoscope ultrasound detection in preoperative T/N staging of gastric cancer." Molecular and Clinical Oncology. July 2013; 1(4):699-702. Web. 30 October 2018. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3915684/>.
5. Altin Malaj, et. al. "CT/MRI accuracy in detecting and determining preoperative stage of gastric adenocarcinoma in Albania." Contemporary Oncology. 2017; 21(2): 168-173. Web. 30 October 2018. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5611507/>.
6. Xianying Huo, et. al. "Clinical value of magnetic resonance imaging in preoperative T staging of gastric cancer and postoperative pathological diagnosis." Oncology Letters. July 2014; 8(1): 275-280. Web. 30 October 2018. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4063621/>.