A retrospective review of demographics and stage of presentation in patients with ER/PR/Her2-neu receptor negative breast cancer.

Abstract #2097 Background: Estrogen receptor/progesterone receptor/Her2-neu receptor negative, or “triple negative” breast cancer (TNBC) is notable for its propensity to metastasize early and display a comparatively more aggressive course. Some estimates comprise approximately 15-20% of all breast cancers, and it is apparently more prevalent in African-American women, Hispanic women, and women younger than 40 years of age. There has been a continual decline in death rates due to breast cancer since 1990 attributed to both earlier detection, as well as better treatment modalities including hormonal blockade in estrogen- and progesterone-receptor positive cancers, as well as the anti-Her2/neu receptor antibody, Trastuzumab. These hormone receptors are not found in TNBC, and therefore the traditional targets for endocrine manipulation cannot be therapeutically exploited. While lower socioeconomic status and racial predisposition to this aggressive disease have been observed, there exists a paucity of research into other demographic risk factors or associations. Methods: We reviewed data between January 2000 to December 2005 from our tumor registry with particular attention to age, race, family history, tobacco use, and stage of presentation, comparing this subset of patients (n=39) to other records (n=303). We included only those patients in whom the status of all three receptors were recorded. Results: Comparisons were made for TNBC vs non-TNBC patients respectively as follows: mean age (59.87±15.67 yrs vs 60.09±13.98 yrs); Black, 58.97% vs 39.27%; White, 35.90% vs 57.76%; Other minorities, 2.56% vs 0.99%; Unknown, 2.56% vs 0.33%. Comparisons with respect to tobacco history for TNBC vs non-TNBC patients respectively: cigarettes, 15.38% vs 18.81%; non smokers, 71.79% vs 61.72%; ex smokers, 5.13% vs 8.91%; chewing tobacco, 0% vs 0.33% and unknown, 7.69% vs 10.23%. Positive family history of cancer, 30.77% vs 33.33%; no family history of cancer, 51.28% vs 51.82%, and unknown, 17.95% vs 14.85%. Pathologic stage at diagnosis for TNBC vs non-TNBC patients respectively: Stage 0, 15.79% vs 11.37%; stage 1, 34.21% vs 30.98%; stage 2, 28.98% vs 37.25%; stage 3, 18.42% vs 17.25%, and stage 4, 3.63% vs 3.14%. Analysis using χ 2 test (χ 2 =0.855) and CMH test for Linear Trend analysis (p=0.4775) showed no difference in percentages in association with the 5 stages or TNBC status and no linear trend respectively. Conclusion: This data suggests that at our institution, TNBC is less prevalent (12.87%) than estimates of 15-20% published in other studies. There was no difference in age at diagnosis (p=0.9272), with black patients more likely to have TNBC (p=0.004, OR=2.755). There was no significant association between smoking status and TNBC (p=0.4385). There was no significant association between a family history of cancer and TNBC (p=0.8384). When accounting for samples size, TNBC was as prevalent as non TNBC at all stages of diagnosis (p=0.4332, p=0.6890, p=0.3205, p=0.8591, and p=0.8651 respectively). These results differ from other published data and may reflect differences in statistical analysis or patient population. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2097.