Diagnostic accuracy of computed tomography alone versus computed tomography combined with ultrasound for diagnosing...

To evaluate and compare the diagnostic accuracy of computed tomography alone versus computed tomography combined with ultrasound for detecting metastatic cervical lymph nodes in patients with thyroid cancer using the Standards for Reporting Diagnostic Accuracy Studies 2015 guidelines.

This retrospective diagnostic accuracy study included 134 patients with thyroid cancer who underwent preoperative computed tomography or ultrasound scans for lymph node metastases at King Abdullah Medical City Hospital, Makkah, KSA, between 2009 and 2020. Histopathological examination was the reference standard. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were assessed for computed tomography alone versus computed tomography combined with ultrasound.

The mean age of the participants was 46 years, and over two-thirds were females. Papillary thyroid carcinoma was the most common diagnosis, followed by follicular and medullary thyroid carcinomas. Lymphovascular invasion was observed in 32% of cases. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the curve were 71.05%, 91.67%, 77.14%, 88.89%, 85.82%, and 0.814, respectively, for computed tomography + ultrasound; and 28.95%, 98.96%, 91.67%, 77.87%, 79.10%, and 0.64 for central cervical nodes (zone VI), and 73.68%, 90.63%, 75.68%, 89.69%, 85.82%, and 0.822 for peripheral cervical nodes.

Computed tomography combined with ultrasound exhibited acceptable diagnostic performance in detecting metastatic cervical lymph nodes in thyroid cancer, but the sensitivity of computed tomography alone was lower for central cervical nodes. Ultrasound-only analysis was not performed, so these findings should be interpreted as supportive of a complementary, multimodal imaging approach rather than as evidence that computed tomography combined with ultrasound is superior to ultrasound alone.