Inflammatory breast cancer in 210 patients: A retrospective study on epidemiological, anatomo-clinical features and therapeutic results

Abstract

To report epidemiological and anatomo-clinical features within a retrospective series of inflammatory breast cancer and to evaluate prognostic factors. This retrospective study included 210 Tunisian patients presenting a clinically diagnosed IBC, treated at the Institute Salah Azaiez (ISA) of Tunis, Tunisia, from 2008 to 2013. We collected data on epidemiology, anatomo-clinical and biological features and histologic response to neoadjuvant therapy. Overall and disease-free survivals were calculated by Kaplan-Meier method and compared by log-rank tests and Cox's models were used to identify prognostic factors impacting survival. The 210 IBC patients had a median age of 42 years (24-62) and 15% of them were aged less than 35 years. Mean age at menarche was 13 years and 45% had their 1st childbirth before 23 years. On histology, grades III represented 42% of cases, hormone receptors were negative in 59%, HER2 over-expressed in 32, 25% of our IBC cases had a triple negative profile and Ki-67 was >20% in 53% of cases. High pathological grade III was significantly correlated to TN subtype (58%) (Fisher's exact test, P=7.5×10^-3). Further, high Ki-67 expression (>20%) was evident in the TN subtype (84%) (Fisher's exact test, P=3.7×10^-4). After neoadjuvant therapy (and trastuzumab in 88 and 69% of HER2+ patients, respectively), we observed 49% of objective clinical responses and 35% of pathological complete response (pCR) and >3 axillary lymph nodes were invaded on a resected tumor in 55% of cases. Overall survival (OS) was associated with age at menarche (Wald-test, P=2.2×10^-2) and metastases at diagnosis (Wald-test, P=2.4×10^-2). Reaching a pCR was correlated with a better metastasis-free survival (MFS), (Fisher's exact test, P=3.6×10^-2).

Keywords: chemotherapy response; epidemiology; histology; immunohistochemistry; inflammatory breast cancer; prognosis; survival.

Figure 1.

Immunohistochemistry in inflammatory breast cancer. (A and B) Absence of expression of ER and PR in IBC tumor cases. (C) Strong expression of HER2 in IBC cases (Score 3). (D and E) Expression of ER and PR in 100% of tumors cells in IBC cases. (F) Absence of expression of HER2 in IBC cases (magnification, ×200). ER, estrogen receptor; PR, progesterone receptor; IBC, inflammatory breast cancer; HER2, human epidermal growth factor receptor 2.