Prevalence of the BRCA1 founder mutation c.5266dupin Brazilian individuals at-risk for the hereditary breast and ovarian cancer syndrome

Table 1 Clinical description of the sample studied (n = 137)

Characteristic	N	%	Mean (SD)
Sex
Female	134	97.8
Male	3	2.2
Age at breast cancer (years)*			42.3 (8.3) range: 24-73
Inclusion criteria
ASCO	113	82.5
Probability of mutation (Myriad) ≥ 30%	62	45.3
Probability of mutation (PENN II model) ≥ 30%	28	20.4
Bilateral breast cancer	34	24.8
Cancer history in the proband (n = 136)**
One primary tumor
Breast cancer	85	62.5
Ovarian cancer	4	2.9
Other#	5	3.7
Multiple primaries:
≥ 2 Breast	31	22.8
≥ 2 ovarian	0	0
1breast and 1 ovarian	2	1.5
≥ 2 Breast and 1 ovarian	3	2.2
At least one breast + other	5	3.7
At least one ovarian + other	1	0.7
Criteria for multiple hereditary cancer syndromes
HBOC + Li-FraumeniLike (Eeles criteria)	23	16.8
HBOC + Li-Fraumeni Like (Birch criteria)	2	1.4
HBOC + Hereditary Breast and Colorectal Cancer	14	10.2
HBOC + Hereditary Non-Polyposis Colorectal Cancer	3	2.2
Cancer family history (1 ^st and 2 ^nd degree relatives)
Number of breast cancer cases			3.3 (1.52)
Number of ovarian cancer cases			1.3 (0.61)
Age at first breast cancer			44.2 (6.8)

*In women with multiple breast cancers, age at the diagnosis of the first primary was considered.
**One patient was cancer unaffected. In the sample of 136 cancer affected probands, there were a total of 184 tumors, including synchronous and metachronous cases.
^#(colorectal, melanoma, gastric, uterine cervix, esophagus, endometrium)

ISSN: 1897-4287