Case control study of prognostic markers and disease outcome in inflammatory carcinoma breast: A unique clinical experience

Inflammatory breast carcinoma (IBC) is a rare but aggressive form of breast cancer. In this first-ever study, we investigated the role of nine prognostic markers' expression (estrogen receptor [ER], progesterone receptor [PR], p53, C-erbB-2, epidermal growth factor receptor [EGFR], cathepsin D [CD], proliferating cell nuclear antigen [PCNA], DNA ploidy, and S-phase fraction [SPF]) and disease outcome in IBC cases compared with the control group. A case control study of IBC was conducted on 40 test cases with two controls per case matching age, grade, and number of axillary lymph nodes sampled. During 7 years of this study, 10% of all patients with breast cancer had IBC. In this study, 84% of IBC cases showed positive axillary lymph nodes compared with 63% in control group. The expression of nine prognostic markers, that is, ER, PR, p53, C-erbB-2, EGFR, CD, PCNA, SPF, and DNA ploidy, was studied by immunohistochemistry and flow cytometry. Hormone receptor status showed an inverse correlation (p < 0.05). Among p53, C-erbB-2, EGFR, and CD in the IBC group, only p53 showed a significant correlation, with 70% positivity in IBC versus 48% positivity in the control group (p < 0.05). Much higher SPF and PCNA positivity was seen in the IBC group compared with the control group (p < 0.05). DNA ploidy also showed a significant correlation compared with the control group (p < 0.05). After a median follow up of 18 months, median overall survival in the IBC group was 1.8 years (range 0.6-5.8 years) compared with 3.0 years (range 2.5-7.0 years), with a p value of 0.0001.