Correlation of the ultrasound thyroid imaging reporting and data system with cytology findings among patients in Uganda

Background Ultrasonography is a noninvasive modality for the initial assessment of thyroid nodules.

The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) has demonstrated good performance in differentiating malignant thyroid nodules.

However, the combination of ACR TI-RADS categories and cytology has not been studied extensively, in Uganda.

The study aims to correlate ACR TI-RADS with cytology among patients referred for US-guided fine-needle aspiration at Mulago National Referral Hospital.

Methods This was a hospital-based cross-sectional study that recruited 132 patients with thyroid nodules.

Spearman’s correlation was used to establish a relationship between TI-RADS and cytology findings.

The diagnostic accuracy of TI-RADS was assessed using sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios.

Results Of 132 study participants, 90% ( n  = 117) were females, and the mean age was 41 ± 13 years.

One hundred sixty-one thyroid nodules were analyzed.

More than half of the thyroid nodules (54.7%, n  = 87) were solid or almost solid, 96.9% ( n  = 154) were shaped wider than tall, 57.2% ( n  = 91) had smooth margins, 83.7% ( n  = 133) were hyperechoic or isoechoic, and 88.7% ( n  = 141) had no echogenic foci.

TI-RADS 3 was the most common at 42.9% ( n  = 69).

The proportions of malignancy for TI-RADS 4 and TI-RADS 5 were 73.3% and 85.7%, respectively.

The correlation between ACR TI-RADS and the Bethesda system of thyroid classification scores was r  = 0.577.

The sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios of ACR TI-RADS were 90.9%, 98.5%, 90%, 99.3%, 62.3, and 0.1, respectively.

Conclusion We found that ACR TI-RADS classification is an appropriate and noninvasive method for assessing thyroid nodules in routine practice.

It can safely reduce the number of unnecessary fine-needle aspiration in a significant proportion of benign thyroid lesions.

Thyroid nodules classified as TI-RADS 3 should be followed routinely.

ACR TI-RADS should be standardized as the screening tool in resource-limited areas.