"Our study adds to current literature by proving that the use of DWI assists in addressing patients to the correct treatment," lead author Dr Francesco Giganti, from the San Raffaele Scientific Institute at Vita-Salute University in Milan, told AuntMinnie.com.
The researchers prospectively compared the diagnostic capabilities of DWI, multidetector-row CT, and endoscopic ultrasonography for the preoperative staging of esophageal cancer. This study is the first in which the three modalities were prospectively compared for this clinical application, Giganti said.
The subjects underwent 1.5-tesla DWI-MRI, 64-channel multidetector-row CT, and endoscopic ultrasonography before and after neoadjuvant treatment.
For tumor staging, DWI showed the greatest specificity and accuracy, while endoscopic ultrasound offered the best sensitivity. For nodal staging, DWI and endoscopic ultrasonography had the highest sensitivity, but none of the three modalities produced adequate specificity. DWI had the highest accuracy for nodal staging.
In addition, patients undergoing surgical resection had significantly higher ADC values than those referred for neoadjuvant therapy, according to the researchers.
"This implies that only patients with low ADC could benefit from chemo/radiotherapy, while those with higher ADC values, if treated with immediate surgical resection, might avoid the side effects of neoadjuvant therapy," Giganti said. "Together, these results indicate that DWI-MRI may have the potential to improve the preoperative workup in esophageal cancer."
Giganti and colleagues believe their study has several strengths and that the initial results are promising.
"We analyzed for the first time two subgroups initially managed with different approaches (surgery versus chemo/radiotherapy), highlighting the differences in terms of quantitative measurements from DWI," he said.
One limitation of the study is the lack of standardized imaging guidelines to stage esophageal cancer, primarily for pathologic node size, he noted. However, to overcome this drawback, the researchers deliberately chose a common dimensional cutoff of 10 mm on the short axis, ensuring reproducibility of the results.
