Table 1

Characteristics of 196 families (third-degree relatives excluded)a

Occurrence ofNumber (%) of affected family histories (total = 196)
0 relatives1 relative2 relatives≥3 relatives
Bilateral breast cancer145 (74)45 (23)5 (3)1 (1)
Ovarian cancer154 (79)26 (13)13 (7)3 (1)
Breast and ovarian cancer in one individual184 (93)11 (6)1 (1)0
Male breast cancer191 (96)6 (3)
More affected relatives
 First degree11 (6)67 (34)77 (39)43 (21)
 Second degree121 (61)43 (22)22 (11)12 (6)
  • a Mean number of breast cancer cases, 2.5 (SD, 1.4); minimum, 0; maximum, 7. Total of 4467 individuals.