Correlation between 4D-CT Enhancement Patterns and Parathyroid Adenoma Cellularity: A Retrospective Study.

BACKGROUND AND PURPOSE: 4D-CT is a well-established technique for preoperative localization of parathyroid adenomas. However, the relationship between enhancement patterns and histologic features such as lesion cellularity remains unclear. This study evaluates whether enhancement patterns correlate with lesion cellularity in surgically-confirmed parathyroid adenomas.

MATERIALS AND METHODS: A retrospective cohort study was performed on 134 patients (194 parathyroid lesions) who underwent 4D-CT for preoperative localization and subsequent parathyroidectomy. After excluding lesions that were not visualized on 4D-CT, not resected, or lacked pathology data on cellularity, 121 lesions in 95 patients were included in the final analysis. Enhancement patterns were categorized into types A, B, or C based on previously published criteria. Cellularity was dichotomized into increased and nonincreased groups using an 80% cutoff. Mixed-effects logistic regression analysis was performed to adjust for potential confounders.

RESULTS: Among the 121 lesions with a reported enhancement pattern and cellularity, 26 (21.5%) exhibited type A enhancement; 65 (53.7%), type B; and 30 (24.8%), type C. Increased cellularity was observed in 88 lesions (72.7%). Type A enhancement was independently associated with increased cellularity (OR, 6.1; 95% CI, 1.3-29.3; P = .02) after adjusting for confounders. Larger lesion size was also a significant predictor of increased cellularity (P < .001). No significant correlation was found between enhancement category B or C and cellularity.

CONCLUSIONS: Type A enhancement on 4D contrast-enhanced neck CT (4D-CT) is independently associated with increased cellularity in parathyroid adenomas. These findings suggest that enhancement kinetics may serve as a surrogate marker for histologic features, providing additional information for preoperative planning and surgical decision-making.