Visual pattern* | Apical expression† | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Sex (M/F) | Median age and range (y) | Median tumor size and range (cm) | Negative | Positive | Negative | Positive | ||||||
Lesion type | n | 0 | 1 | 2 | 3 | − | + | ++ | +++ | |||
Nononcocytic | ||||||||||||
Microfollicular goiter | 9 | 3/6 | 59; 54–69 | 2.00; 1.20–4.00 | 3 | 4 | 2 | — | 1 | 1 | 5 | 2 |
Follicular adenoma | 12 | 1/11 | 48; 35–71 | 1.85; 1.00–3.50 | 1 | 9 | 2 | — | 3 | 2 | 6 | 1 |
Minimally invasive follicular carcinoma | 2 | 0/2 | 39.5; 36–43 | 3.65; 3.50–3.80 | — | — | 2 | — | 1 | — | 1 | — |
Follicular variant of papillary carcinoma | 12 | 3/9 | 51; 28–62 | 1.35; 1.00–3.00 | — | 4 | 8 | — | 10 | — | 2 | — |
Poorly differentiated carcinoma | 1 | 1/0 | 72 | 4.00 | — | — | 1 | — | 1 | — | — | — |
Oncocytic | ||||||||||||
Microfollicular goiter | 5 | 1/4 | 60; 46–65 | 2.50; 1.00–3.00 | — | — | 4 | 1 | 4 | — | 1 | — |
Follicular adenoma | 6 | 1/5 | 46.5; 36–68 | 1.75; 1.00–2.90 | — | 1 | 4 | 1 | 3 | — | 3 | — |
Follicular variant of papillary carcinoma | 3 | 0/3 | 69; 42–70 | 1.60; 1.10–1.60 | — | — | 3 | — | 3 | — | — | — |
Insular carcinoma | 1 | 1/0 | 72 | 8.00 | — | — | 1 | — | 1 | — | — | — |
↵* Visual 99mTc-MIBI images were assessed using the following scoring system: pattern 0, no increased uptake of the nodule in either early or delayed images; pattern 1, increased uptake by nodule only in early images; pattern 2, increased uptake by nodule both in early and in delayed images; and pattern 3, increased uptake by nodule only in delayed images. For statistical analysis, visual scintigraphic patterns 0 or 1 and 2 or 3 were considered negative and positive, respectively.
↵† MRP1 apical immunoreactivity was analyzed using the following scale: −, no reactivity; +, <25% positive follicular cells; ++, 25%−50% positive follicular cells; and +++, >50% positive follicular cells. For statistical analysis, MRP1 was considered positive when apical membrane immunoreactivity was observed in >25% of tumor cells (++ and +++).