Table 1.
Patient, Tumor, and Treatment Characteristics
| Characteristic | Cohort 1,a No. (%) (n = 561) | Cohort 2,a No. (%) (n = 104) |
|---|---|---|
| Age, years | ||
| ≤ 39 | 13 (2) | 4 (4) |
| 40-49 | 93 (17) | 21 (20) |
| 50-59 | 166 (30) | 30 (29) |
| 60-69 | 146 (26) | 28 (27) |
| ≥ 70 | 143 (25) | 21 (20) |
| Race/ethnicityb | ||
| White | 519 (93) | 95 (95) |
| Hispanic | 8 (1) | 1 (1) |
| Black | 16 (3) | 4 (4) |
| Other | 14 (3) | 0 (0) |
| Menopausal statusc | ||
| Premenopausal | 134 (24) | 29 (28) |
| Postmenopausal | 427 (76) | 75 (72) |
| Tumor size, mmd | ||
| ≤ 5 | 226 (40) | 28 (27) |
| 6-10 | 231 (41) | 61 (59) |
| > 10 | 104 (19) | 15 (14) |
| Minimum negative margin width, mm | ||
| < 1e | 9 (2) | 2 (2) |
| 1-2.9e | 10 (2) | 2 (2) |
| 3-4.9 | 184 (33) | 28 (27) |
| 5-9.9 | 239 (43) | 47 (45) |
| ≥ 10f | 119 (21) | 25 (24) |
| Method of detectionb | ||
| Microcalcifications | 399 (71) | 88 (85) |
| Density or mass | 93 (17) | 4 (4) |
| Both | 40 (7) | 7 (7) |
| Incidental finding | 19 (3) | 5 (5) |
| Other | 8 (1) | 0 (0) |
| Bloody nipple dischargeb | ||
| Yes | 12 (2) | 1 (1) |
| No | 541 (98) | 102 (99) |
| Tamoxifen use | ||
| Yes | 174 (31) | 25 (24) |
| No | 387 (69) | 79 (76) |
| Hormone replacement therapy before study entryb | ||
| Yes | 239 (43) | 47 (45) |
| No | 315 (57) | 57 (55) |
| Treating institution gradeg | ||
| Low | 281 (50) | 0 (0) |
| Intermediate | 280 (50) | 0 (0) |
| High | 0 (0) | 104 (100) |
| CAP gradeh | ||
| Low | 61 (15) | 2 (2) |
| Intermediate | 249 (59) | 19 (24) |
| High | 110 (26) | 59 (74) |
Abbreviation: CAP, College of American Pathologists.
Cohort 1 defined as low- or intermediate-grade ductal carcinoma in situ (DCIS), tumor size 2.5 cm or smaller. Cohort 2 defined as high-grade DCIS, tumor size 1.0 cm or smaller. Cohort assignment was based on clinical evaluation and pathology assessment from the treating institution at the time of enrollment onto the study.
Unknown cases and cases that were not evaluated were excluded.
Patients younger than age 50 years were assumed to be premenopausal when menopausal status was not recorded.
Tumor size was based on central pathology review, when this information was available.
Cases with negative margin width less than 3 mm were determined on central pathology review.
Cases with no tumor on re-excision are included.
Grade as determined on pathology assessment from the treating institution at the time of enrollment onto study.
Grade as determined on central pathology review using current CAP guidelines. Cases that were not evaluated were excluded.