Table 3.
MDCT image features for difficult‐to‐diagnosis pathologies of anterior mediastinal lesions
| P value† | |||||
|---|---|---|---|---|---|
| Thymic bed cyst | Thymoma | Thymic carcinoma | TC versus Tm | Tm versus TCa | |
| Age >60 | 32.4% (46/142) | 29.1% (53/182) | 55.9% (33/59) | 0.608 | 0.0003 |
| Location | |||||
| Longitudinal | |||||
| Superior | 91.5% (130/142) | 80.2% (146/182) | 89.8% (53/59) | 0.005 | 0.092 |
| Inferior | 8.5% (12/142) | 19.8% (36/182) | 10.2% (6/59) | ||
| Laterality | |||||
| Median location | 104/142 (73.2%) | 58/182 (31.9%) | 39.0% (23/59) | <0.0001 | 0.487 |
| Lesion characteristics | |||||
| Size (cm, mean ± SD) | 2.86 ± 4.62 | 4.88 ± 2.10 | 5.00 ± 2.29 | <0.0001 | 0.717 |
| Contour | |||||
| Smooth | 83.8% (119/142) | 28.0% (51/182) | 23.7% (14/59) | <0.0001 | 0.484 |
| Lobulated | 16.2% (23/142) | 72.0% (131/182) | 76.3% (45/59) | ||
| Margin | |||||
| Well‐demarcated | 89.4% (127/142) | 46.7% (85/182) | 25.4% (15/59) | <0.0001 | <0.0001 |
| Focal‐bulging | 4.2% (6/142) | 31.9% (58/182) | 22.0% (13/59) | ||
| Ill‐defined | 6.3% (9/142) | 21.4% (39/182) | 52.5% (31/59) | ||
| Shape | |||||
| Round | 31.7% (45/142) | 19.8% (36/182) | 20.3% (12/59) | 0.014 | 0.926 |
| Oval/irregular | 68.3% (97/142) | 80.2% (146/182) | 79.7% (47/59) | ||
| Focal cystic/necrotic change | 0.7% (1/142) | 33.0% (60/182) | 50.8% (30/59) | <0.0001 | 0.002 |
| Calcification | 2.8% (4/142) | 17.6% (32/182) | 13.6% (8/59) | <0.0001 | 0.519 |
| Gross fat | 0.0% (0/142) | 0/0% (0/182) | 0/0% (0/59) | — | |
| Adjacent organ invasion | 0.0% (0/142) | 10.3% (17/182) | 33.9% (20/59) | 0.0002 | <0.0001 |
| Ancillary features | |||||
| Pleural effusion | 0.0% (0/142) | 3.3% (6/182) | 6.8% (4/55) | 0.029 | 0.004 |
| Pericardial effusion | 0.0% (0/142) | 0.5% (1/182) | 8.5% (5/54) | 0.378 | 0.098 |
| Mediastinal LN enlargement | 0.0% (0/142) | 2.7% (5/182) | 18.6% (11/59) | 0.046 | <0.0001 |
| Distant metastasis | 0.0% (0/142) | 7.7% (14/182) | 16.9% (10/59) | 0.002 | 0.063 |
| Satellite lesions | 2.1% (3/142) | 3.8% (7/182) | 1.7% (1/59) | 0.367 | 0.065 |
| Enhancement pattern | |||||
| Attenuation (precontrast) (HU, mean ± SD) | 34.3 ± 18.7 | 45.8 ± 11.6 | 45.7 ± 18.8 | <0.0001 | 0.978 |
| Water‐attenuated on precontrast scan‡ | 26.2% (28/107) | 2.2% (3/138) | 2.2% (1/46) | <0.0001 | 0.574 |
| Attenuation (postcontrast) (HU, mean ± SD) | 36.7 ± 20.4 | 86.8 ± 25.5 | 79.2 ± 22.2 | <0.0001 | 0.049 |
| Water‐attenuated on postcontrast scan† | 23.8% (30/126) | 0.0% (0/176) | 0.0% (0/59) | <0.0001 | — |
| Homogeneous enhancement | 95.9% (118/123) | 59.0% (102/173) | 45.8% (27/54) | <0.0001 | 0.247 |
†
P‐values are from the Student's t‐test or chi‐squared test, as appropriate. Significant P‐values (<0.05) were underlined.
‡
“Water‐attenuated” indicates with a CT attenuation not greater than 20 HU.
TC, thymic bed cyst; TCa, thymic carcinoma; Tm, thymoma.