Age-related frequency of triple negative breast cancer in women

Abstract

Objective: To determine frequency of triple negative breast cancer (TNBC) in Pakistani women with respect to age.

Study design: Observational study.

Place and duration of study: Armed Forces Institute of Pathology (AFIP), Rawalpindi, from July 2005 to July 2010.

Methodology: Pathological records of all specimens of breast cancer were reviewed and data was obtained for estrogen receptor (ER), progesterone receptor (PR) and HER-2 neu receptor proteins. Specimens having complete record of all three proteins were included for analysis. TNBC was defined as those who were ER, PR and HER-2 neu negative. Overall frequency as well as frequency with respect to age was calculated. Descriptive and categorical variables were analyzed using SPSS version 17.

Results: Eight hundred and fifteen patients out of 4715 (17.28%) were found to be TNBC. Mean age of diagnosis of TNBC was found to be 46.26 ± 12.22 years of age while other breast cancers had a mean age 52.90 ± 9.78 years (p < 0.001). In the TNBC group, 537 patients (65.88%) were aged < 50 years while 278 patients (34.11%) were aged > 50 years while majority of patients with other breast cancers were elderly females (p < 0.001).

Conclusion: TNBC comprised 17.28% of the breast cancers in Pakistani women diagnosed at the studied centre. A higher frequency of TNBC was noted in significantly younger patients.