Table 1.
Characteristics of women diagnosed with Hodgkin lymphoma (HL) at age 30 years or younger who developed breast cancer, and matched controls
| Patients, no. (%); n = 105 | Matched control subjects, no. (%); n = 266 | |
|---|---|---|
| Cancer registry | ||
| Denmark | 15 (14.3) | 29 (10.9) |
| Finland | 10 (9.5) | 19 (7.1) |
| Iowa | 4 (3.8) | 8 (3.0) |
| The Netherlands | 40 (38.1) | 138 (51.9) |
| Ontario | 20 (19.1) | 40 (15.0) |
| Sweden | 16 (15.2) | 32 (12.0) |
| Age at diagnosis of HL, y | ||
| 13-21 | 50 (47.6) | 120 (45.2) |
| 22-30 | 55 (52.4) | 146 (54.8) |
| Year of diagnosis of HL | ||
| Earlier than 1970 | 34 (32.4) | 68 (25.6) |
| 1970-79 | 61 (58.1) | 165 (62.0) |
| 1980-94 | 10 (9.5) | 33 (12.4) |
| Age at diagnosis of breast cancer/cutoff date in controls, y | ||
| 27-41 | 58 (55.2) | 139 (52.3) |
| 42-57 | 47 (44.8) | 127 (47.7) |
| Treatment for HL | ||
| Radiation dose to specific breast location, Gy | ||
| 0-4.9 | 23 (21.9) | 95 (35.7) |
| 5.0-23.0 | 23 (21.9) | 47 (17.7) |
| 23.1-37.1 | 29 (27.6) | 63 (23.7) |
| 37.2-61.3 | 30 (28.6) | 61 (22.9) |
| Alkylating agent chemotherapy | ||
| No | 68 (64.8) | 132 (49.6) |
| Yes | 37 (35.2) | 134 (50.4) |
| Radiation dose to ovaries, Gy | ||
| Lower than 5 | 98 (93.3) | 226 (85.0) |
| 5 or higher | 7 (6.7) | 40 (15.0) |
| Interval to breast cancer, y | ||
| 1-4 | 0 | NA |
| 5-14 | 31 (29.6) | NA |
| 15-24 | 60 (57.1) | NA |
| ≥ 25 | 14 (13.3) | NA |
NA indicates not applicable.