Pathological, clinical and prognostic characteristics of breast cancer in Central Sudan versus Northern Italy: implications for breast cancer in Africa

Abstract

Aims: In patients of Black African ethnicity, breast cancer is reportedly characterized by aggressive, poorly differentiated phenotype(s). To highlight possible differences between breast cancer in indigenous sub-Saharan African and European patients, two breast cancer case series, from Central Sudan (Khartoum) and Northern Italy (Milan), were compared for clinicopathological characteristics, expression of oestrogen receptor (ER), progesterone receptor (PR), Her-2/neu, basal cytokeratin (CK) 5/6 and CK17, and breast cancer subtypes.

Methods and results: After careful antigen retrieval, 114 and 138 consecutive formalin-fixed paraffin-embedded (FFPE) breast cancer cases from the Radiation and Isotope Centre (Khartoum) and from MultiMedica (Milan), respectively, were screened by immunohistochemistry for ER, PR, Her-2/neu, CK5/6 and CK17. Compared with the Italian patients, the Sudanese patients were younger (P < 0.0001) and their tumours were larger (P < 0.0001), more advanced in stage (P < 0.00001), higher grade (P < 0.00001) and more frequently positive for nodal metastases (P < 0.00001). ER expression varied between the two series (P < 0.0008), but no significant differences were found for PR (P < 0.32), combined hormone receptors (P < 0.12), Her-2/neu (P < 0.09), CK5/6 (P < 0.1), CK17 (P = 0.4), combined basal CK status (P = 1) or breast cancer subtypes (P = 0.12).

Conclusion: The differences between the Sudanese and Italian breast cancer series reflect stage at diagnosis rather than intrinsic biological characteristics. This may have relevant implications for breast cancer prevention and treatment in Africa.