BACKGROUND: Prospective trials of non-surgical observation have shown progression rates of only 5-10  % in @entity1 with asymptomatic @entity7172 ( @entity7172 ). This study investigated time-dependent changes in calcification patterns and @entity5 vascularity on ultrasonography (US) to clarify the natural course of @entity7172 . METHODS: We examined calcification patterns and @entity5 vascularity for 480 lesions in 384 @entity1 . Calcification patterns were classified as: (A) none; (B) micro; (C) macro; or (D) rim. @entity5 vascularity was classified as rich or poor via color Doppler US. RESULTS: After a mean of 6.8  years of observation, 29 lesions (6.0  %) had increased in size. Mean age for initial calcification pattern was 52.1  years for A (n  =  135), 54.2  years for B (n  =  235), 56.3  years for C (n  =  96), and 60.1  years for D (n  =  14), and the incidence rates of @entity5 enlargement were 9.6, 5.5, 3.2, and 0  %, respectively. The cumulative rate of upgrade in calcification pattern was 51.8  % at 10  years. Lesions with initially rich vascularity (n  =  70) had significantly higher rate of @entity5 enlargement than those with poor vascularity (n  =  410); however, the majority of @entity5 (61.4  %) with initially rich vascularity had decreased their blood supply during the follow-up. Multivariate analysis showed that strong calcification (C or D) and poor vascularity at last examination correlated significantly with @entity74 . CONCLUSIONS: PMCs in older @entity1 showed significantly stronger calcification patterns and poorer vascularity. Both consolidation of calcification and loss of vascularity occurred in a time-dependent manner during observation and were significant indicators for @entity74 .

Natural History of Asymptomatic XXXX : Time-Dependent Changes in Calcification and Vascularity During Active Surveillance.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity74 :: ('MESH:D030342', 'Disease') :: ['non-progressive disease'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'Tumor'] @entity7172 :: ('MESH:C563277', 'Disease') :: ['papillary microcarcinoma', 'PMC']
@entity7172 :: (MESH:C563277,Disease) :: ['Papillary Thyroid Microcarcinoma']
