Accuracy of Diffusion Weighted Imaging in Assessment of Pelvic Lymphnode Metastasis in Patients with Endometrial Cancer

Objective: To evaluate the sensitivity and specificity of diffusion-weighted imaging in determining metastatic pelvic lymph nodes in patients of endometrial cancer and comparing its accuracy with contrast-enhanced sequence of MRI, taking histopathology as gold standard. Study Design: Retrospective Study. Place and Duration of the Study: Department of Radiology, the Aga Khan University Hospital Karachi, from January to December 2021. Methodology: Fifty-eight adult females with biopsy proven endometrial carcinoma and complete medical records were included through convenience sampling. Patients who did not have complete medical records were excluded. Studied variables included signal characteristics of lymph nodes and their short axis diameter. The sensitivity and specificity of DWI and contrast-enhanced MRI for evaluation of diseased lymph nodes were calculated using histopathology as the gold standard. Results: Among 58 patients with histopathologically proven endometrial cancer, 14 had metastatic lymphadenopathy. DWI-weighted imaging in the evaluation of metastatic and non-metastatic lymph nodes had sensitivity of 81.1% while specificity, the positive and negative predictive value of 88.8%, 72.2%, and 82.5% and on contrast-enhanced imaging as 66.6%, 58.1%, 35.7%, and 83.3%, respectively. Conclusion: The DWI shows better accuracy in evaluation and discrimination between metastatic and non-metastatic lymph nodes as compared to contrast-enhanced MRI examination for the evaluation of diseased lymph nodes in patients with endometrial cancer.