PET/MRI Better Than PET/CT in Cancer Detection
Positron emission tomography/magnetic resonance imaging (PET/MRI) improves lesion detection, reduces the need for additional examinations and significantly reduces the overall radiation exposure in cancer when compared to PET/CT, according to a newstudy.
PET/MRI can potentially help promote fast and efficient local and whole-body staging in one step. It can be particularly beneficial to pediatric and adolescent patients.
‘Positron emission tomography/magnetic resonance imaging (PET/MRI) improves lesion detection and reduces radiation exposure and additional examinations in several cancers. PET/MRI could be used for treatment monitoring in cancer patients.’
The study is published in The Journal of Nuclear Medicine.
PET/CT is known as the diagnostic cornerstone due to its high-resolution morphologic imaging and sensitivity. PET/MRI has higher soft-tissue contrast and lower radiation exposure.
There is no sufficient clinical data for PET/MRI due to the lack of clinical studies with relevant sample size.
The current study compared 1,003 whole-body PET/MRI examinations with whole-body PET/CT examinations on 918 patients from a single center.
The oncological indications included lung cancer, gastrointestinal cancer or neuroendocrine cancer, head and neck cancer, prostate cancer, lymphoma, gynecologic or breast cancer melanoma, malignant bone disease, and cancer of unknown primary.
Certified nuclear medicine physicians and radiologists evaluated the PET/MRI and PET/CT examinations. They identified:
- Additional findings and probable diagnosis on PET/MRI that were missing on PET/CT
- Additional but indeterminate findings on PET/MRI requiring additional examinations or follow-up
- Classification of indeterminate findings on PET/CT by PET/MRI
- Missed findings on PET/MRI in comparison to PET/CT
- PET/MRI reported additional finding in 26.3% of the examinations when compared with PET/CT
- In the 26.3%, additional malignant findings were detected in 5.3%.
- A change in TNM staging in 2.9% due to PET/MRI
- Definite lesion classification of indeterminate PET/CT findings was possible in 11.1% using PET/MRI
- In 2.9 %, lesions detected on PET/CT were not visible on PET/MRI.
- Malignant lesions were missed in 1.2 % on PET/MRI, leading to a change in TNM staging in 0.5%
- Estimated mean effective dose for whole-body PET/CT amounted to 17.6 � 8.7 mSv, in comparison to 3.6 � 1.4 mSv for PET/MRI
- PET/MRI resulted in a potential dose reduction of 79.6 %.
"Hybrid imaging examinations are now part of complex diagnostic algorithms in multiple cancer types. Based on our data, PET/MRI could be an important adjunct to PET/CT by providing diagnostic advantages and improving diagnostic algorithms in numerous cancers at the same time. Furthermore, the markedly reduced radiation exposure of PET/MRI could lead to a more frequent use of this examination in oncological patients, most notably for treatment monitoring," said Benedikt Schaarschmidt, MD, professor and radiologist at the University Hospital Essen in Essen, Germany.
Source: Medindia