Inflammatory breast cancers in Tunisia and France show similar immunophenotypes.

Purpose: Inflammatory breast cancers (IBC) have specific immunophenotypic profiles as compared to non-inflammatory (non-IBC): combined differential expression of estrogen receptor, Ki67, E-cadherin, MUC1, and ERBB2 can be used as an IBC signature. It is thought that IBC occurs with a high frequency in Tunisia. The aim of this study is to evaluate this signature on a Tunisian series.
Methods: The expression of five proteins (E-cadherin, ERBB2, estrogen receptor, Ki67, MUC1) was studied by immunohistochemistry on a consecutive series of 91 cases of IBC (T4D) treated at Tunisian Salah Azaiz Institute (ISA) and deposited in a tissue microarray (TMA). Results were compared to the same study on a series of 85 cases treated in France.
Results: The ISA cases were characterized by a significantly younger age of patients (median: 42 years old in ISA for 53.5 in IPC, p=0.00042) and a higher frequency of invasive micropapillary pattern. None of the five parameters was expressed differentially in the two series. In non-metastatic patients, high level of proliferation (Ki67) and overexpression of ERBB2 were associated with poor outcome.
Conclusion: The IBC from Tunisia were not different from those observed in France on the basis of IHC profiles. However, the younger age of the patients suggest a specific epidemiological context that should be investigated.