Table 3.
Tumor characteristics of interval cancers, stratified by negative index screening, dismissed at index screening, and false-positive screening results in BreastScreen Norway
| All (n = 911) | Concordant negative (n = 735) | Dismissed (n = 117) | False-positive screening result (n = 59) | p value* | |
|---|---|---|---|---|---|
| Histopathological type | < 0.001 | ||||
| Ductal carcinoma in situ | 43 (4.7) | 27 (3.7) | 4 (3.4) | 12 (20.3) | |
| Invasive carcinoma NST | 716 (78.6) | 584 (79.5) | 97 (82.9) | 35 (59.3) | |
| Invasive lobular carcinoma | 122 (13.4) | 99 (13.5) | 13 (11.1) | 10 (17.0) | |
| Other invasive cancers | 30 (3.3) | 25 (3.4) | 3 (2.6) | 2 (3.4) | |
| Invasive tumors | 868 (95.3) | 708 (96.3) | 113 (96.6) | 47 (79.7) | < 0.001 |
| Tumor diameter median (IQR), mm | 19 (13–26) | 19 (13–26) | 20 (14–29) | 15 (11–22) | 0.089 |
| Data not available | 77 | 64 | 9 | 4 | |
| Histological grade | 0.192 | ||||
| Grade 1 | 97 (11.6) | 76 (11.1) | 12 (11.2) | 9 (20.0) | |
| Grade 2 | 386 (46.2) | 325 (47.5) | 42 (39.3) | 19 (42.2) | |
| Grade 3 | 353 (42.2) | 283 (41.4) | 53 (49.5) | 17 (37.8) | |
| Data not available | 32 | 24 | 6 | 2 | |
| Lymph node positive | 325 (39.5) | 268 (39.9) | 45 (42.1) | 12 (27.9) | 0.248 |
| Data not available | 45 | 36 | 6 | 4 | |
| Immunohistochemical subtypes | 0.286 | ||||
| Luminal A–like (ER+/PR+/Her2−) | 355 (46.5) | 1286 (46.4) | 145 (43.7) | 24 (55.8) | |
| Luminal B–like Her2− (ER+/PR−/Her2−) | 115 (15.1) | 90 (14.6) | 16 (15.5) | 9 (20.9) | |
| Luminal B–like Her2+ (ER+/PR±/Her2+) | 140 (18.3) | 111 (18.0) | 26 (25.2) | 3 (7.0) | |
| Her2+ (ER−/PR−/Her2+) | 48 (6.3) | 42 (6.8) | 4 (3.9) | 2 (4.7) | |
| Triple negative (ER−/PR−/Her2−) | 105 (13.8) | 88 (14.3) | 12 (11.7) | 5 (11.6) | |
| Data not available | 105 | 91 | 10 | 4 |
Unless otherwise specified, data are presented as numbers with percentage in parenthesis
IQR interquartile range, NST no special type, ER estrogen receptor, PR progesterone receptor, Her2 human epidermal growth factor receptor
*Overall p value for association between concordant negative/dismissed/false-positive screening results, and the different tumor characteristics