BACKGROUND:
We assembled needed data on the prevalence and characteristics of
BRCA1/2 in Japan.
MATERIALS AND METHODS:
Our
study of BRCA1/2 collected data at eight institutions in
Japan on 320
individuals with a strong family history of breast cancer, according to
the NCCN guidelines, by the end of March 2012.
RESULTS:
Among
260 proband cases, 46 (17.7 %) were positive for BRCA1, and 35 (13.5 %)
were BRCA2-positive. Therefore, the total pathological mutation rate
was 30.7 %. Pathology data after breast surgery were obtained from 37
cases of BRCA1 mutation, 23 (62.2 %) of which were triple negative (TN).
On the other hand, 29 cases (82.9 %) of BRCA2 mutations were Luminal
type. The most prevalent BRCA1 mutation site was L63X, found in 10
families. L63X was reported previously by studies in Japan, and it may
be a founder mutation. We found two cases of large deletion detected by
multiplex ligation-dependent probe amplification. One was an entire
deletion of exon 20 and the lacked exons 1-9.
TN with a family history
of ovarian cancer was 11/20 (55 %). TN under 40-year-old (y.o.) 15/23
(65.2 %) and TN with one or more breast cancers in
family history 17/32
(53.1 %) showed higher incidences of BRCA1 mutation.
CONCLUSION:
Hereditary
breast and ovarian cancer (HBOC) may have nearly the same prevalence in
Japan as in the US or Europe. If TN cases are taken into account, the
ratio of BRCA1 is higher. L63X may be one of the founder mutations in
Japan. A nationwide database of HBOC is important to develop risk models
for BRCA1/2 carriers in Japan.
0 comments :
Post a Comment
Your comments?
Note: Only a member of this blog may post a comment.