Dataset Information

Long-term outcomes of breast cancer in women aged 30 years or younger, based on family history, pathology and BRCA1/BRCA2/TP53 status.

ABSTRACT:

Background

There are relatively few articles addressing long-term follow-up in women with breast cancer at very young ages.

Methods

We have updated and extended our population-based analysis of breast cancer diagnosed at the age < or =30 years in North-west England to include an extra 15 patients with mutation testing in BRCA1, BRCA2 and TP53, with 115 of 288 consecutive cases being tested. Kaplan-Meier curves were generated to assess overall survival, contralateral breast cancer and other second primaries.

Results

Survival analysis of all 288 patients showed poor overall survival, although this improved from a 15-year survival of only 46% in those diagnosed between 1980 and 1989 to 58% in those diagnosed between 1990 and 1997 (P=0.05). Contralateral breast cancer rates were at a steady rate of 0.6 per 1000, although the rates in mutation carriers were approximately 2 per 1000. Altogether, 16 BRCA1, 9 BRCA2 and 6 TP53 mutations have now been found among the 115 cases on whom DNA analysis has been performed. BRCAPRO accurately predicted the number of carriers for BRCA1 and BRCA2 and was sensitive and specific at the 10 and 20% threshold, respectively. However, BRCAPRO did not seem to give any weight to DCIS, which accounted for two BRCA1 carriers and three TP53 carriers and overpredicted mutations at the high end of the spectrum, with only 6 of 11 (54%) with a >90% probability having identifiable BRCA1/2 mutations.

Interpretation

Rates of new primaries are predicted to some extent by mutation status. BRCAPRO is useful at determining those patients aged < or =30 years to be tested.

SUBMITTER: Evans DG

PROVIDER: S-EPMC2853095 | biostudies-literature |

REPOSITORIES: biostudies-literature

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