Table 2.
Performance of tests and combination test strategies
| ACC (n=98) | Other malignant tumours (n=65) | All non-ACC tumours (n=1919) | ACA (n=1767) | Other benign tumours (n=87) | Total (n=2017) | Percentage of ACC cases (95% CI) | Percentage of non-ACC cases (95% CI) | Likelihood ratio (95% CI) | Post-test probability of ACC (per 100 participants with results) | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Single-test strategies | |||||||||||
| Tumour diameter | |||||||||||
| ≥4 cm | 96 | 46 | 392 | 296 | 50 | 488 | 98·0% (92·8–99·8)* | 20·4% (18·6–22·3) | 4·8 (4·4–5·3) | 19·7 (16·2–23·5) | |
| <4 cm | 2 | 19 | 1527 | 1471 | 37 | 1529 | 2·0% (0·2–7·2) | 79·6% (77·7–81·4)† | 0·03 (0·01–0·10) | 0·1 (0·0–0·5) | |
| Imaging characteristics‡ | |||||||||||
| Positive | 97 | 63 | 396 | 289 | 44 | 493 | 99·0% (94·4–100·0)* | 20·6% (18·8–22·5) | 4·8 (4·4–5·3) | 19·7 (16·3–23·5) | |
| Negative | 1 | 2 | 1523 | 1478 | 43 | 1524 | 1·0% (0·0–5·6) | 79·4% (77·5–81·2)† | 0·01 (0·00–0·09) | 0·1 (0·0–0·4) | |
| Urine steroid metabolomics | |||||||||||
| High risk of ACC | 83 | 7 | 157 | 143 | 7 | 240 | 84·7% (76·0–91·2) | 8·2% (7·0–9·5) | 10·4 (8·7–12·3) | 34·6 (28·6–41·0) | |
| Moderate risk of ACC | 13 | 28 | 655 | 578 | 49 | 668 | 13·3% (7·3–21·6) | 34·1% (32·0–36·3) | 0·39 (0·23–0·65) | 1·9 (1·0–3·3) | |
| Low risk of ACC | 2 | 30 | 1107 | 1046 | 31 | 1109 | 2·0% (0·2–7·2) | 57·7% (55·4–59·9) | 0·04 (0·01–0·14) | 0·2 (0·0–0·6) | |
| Combined-test strategies | |||||||||||
| Tumour diameter and imaging characteristics‡ | |||||||||||
| ≥4 cm and positive | 95 | 45 | 152 | 83 | 24 | 247 | 96·9% (91·3–99·4)* | 7·9% (6·8–9·2) | 12·2 (10·5–14·3) | 38·5 (32·4–44·8) | |
| <4 cm, negative, or both | 3 | 20 | 1767 | 1684 | 63 | 1770 | 3·1% (0·6–8·7) | 92·1% (90·8–93·2)† | 0·03 (0·01–0·10) | 0·2 (0·0–0·5) | |
| Tumour diameter and urine steroid metabolomics | |||||||||||
| ≥4 cm and high risk of ACC | 82 | 7 | 46 | 33 | 6 | 128 | 83·7% (74·8–90·4) | 2·4% (1·8–3·2) | 34·9 (25·9–47·1) | 64·1 (55·1–72·3) | |
| ≥4 cm and moderate risk of ACC | 12 | 20 | 130 | 85 | 25 | 142 | 12·2% (6·5–20·4) | 6·8% (5·7–8·0) | 1·8 (1·0–3·2) | 8·5 (4·4–14·3) | |
| <4 cm, low risk of ACC, or both | 4 | 38 | 1743 | 1649 | 56 | 1747 | 4·1% (1·1–10·1) | 90·8% (89·4–92·1) | 0·04 (0·02–0·12) | 0·2 (0·0–0·6) | |
| Imaging characteristics‡ and urine steroid metabolomics | |||||||||||
| Positive and high risk of ACC | 82 | 6 | 43 | 35 | 2 | 125 | 83·7% (74·8–90·4) | 2·2% (1·6–3·0) | 37·3 (27·4–50·8) | 65·6 (56·6–73·9) | |
| Positive and moderate risk of ACC | 13 | 28 | 155 | 97 | 30 | 168 | 13·3% (7·3–21·6) | 8·0% (6·9–9·4) | 1·69 (1·00–2·87) | 7·7 (4·2–12·9) | |
| Negative, low risk of ACC, or both | 3 | 31 | 1721 | 1635 | 55 | 1724 | 3·1% (0·6–8·7) | 89·7% (88·2–91·0) | 0·03 (0·01–0·10) | 0·2 (0·0–0·5) | |
| Tumour diameter, imaging characteristics‡, and urine steroid metabolomics | |||||||||||
| ≥4 cm, positive, and high risk of ACC | 81 | 6 | 25 | 17 | 2 | 106 | 82·7% (73·7–89·6) | 1·3% (0·8–1·9) | 63·4 (42·5–94·6) | 76·4 (67·2–84·1) | |
| ≥4 cm, positive, and moderate risk of ACC | 12 | 20 | 58 | 23 | 15 | 70 | 12·2% (6·5–20·4) | 3·0% (2·3–3·9) | 4·1 (2·3–7·3) | 17·1 (9·2–28·0) | |
| <4 cm, negative, low risk of ACC, or a combination | 5 | 39 | 1836 | 1727 | 70 | 1841 | 5·1% (1·7–11·5) | 95·7% (94·7–96·5) | 0·05 (0·02–0·13) | 0·3 (0·0–0·6) | |
Data in columns one to six are numbers of participants. ACC=adrenocortical carcinoma. ACA=adrenocortical adenoma.
*
Sensitivity.
†
Specificity.
‡
Positive was classified as unenhanced CT attenuation >20 Houndsfield units in homogeneous tumours or heterogeneous tumours precluding measurement of attenuation.