Are There Differences in Androgen Receptor Expression in Invasive Breast Cancer in African (Tanzanian) Population in Comparison With the Caucasian (Italian) Population?

Abstract

PurposeAndrogen receptor (AR) has been shown to have prognostic implication on breast cancer (BC). Data on the biological features of African BCs are poor. We decided for the first time to compare AR expression of Tanzanian and Italian BC patients.Patients and methodsOf the 69 consecutive patients seen at the Bugando Medical Center (Mwanza, Tanzania) from 2003 to 2010, who underwent resection of primary BC evaluable for estrogen receptor, progesterone receptor (PgR), and HER2 only 65 were evaluable for AR by immunohistochemistry. Histopathological assessment and biomolecular determinations were performed at the Cancer Institute of Romagna [Istituto Scientifico Romagnolo per lo studio e la cura dei tumori (IRST)—IRCCS, Meldola, Italy]. Caucasian BC patients were selected from an electronic database and matched (1:2 ratio) for year of diagnosis and age at diagnosis.ResultsThe median age of patients at diagnosis was 51 (range 29–83) years for Tanzanian and 53 (range 26–86) years for Italian patients. Tanzanian patients harbored tumors with lower AR expression than Italian patients according to the median percentage of immunopositive tumor cells (30% versus 80%, p < 0.0001) and staining intensity (p = 0.0003). The proportion of AR negative patients was likewise higher among Tanzanian patients as regards both ≥1% and ≥10% cutoffs. AR-positive BCs were higher in luminal A and B tumors and decreased in triple-negative (TN) and HER2-enriched tumors in Tanzanian population.ConclusionAR loss could represent an unfavorable prognostic marker in the African population. The high frequency of TN tumors with high AR expression could open new perspectives of therapy for population in this low income country.

Distribution and characteristics of androgen receptor (AR) in breast cancer among women in Addis Ababa, Ethiopia: A cross sectional study

“…This result is comparable to previous studies conducted in other parts of the world mainly in the western countries (70-90%) [8,14,17,[21][22][23]. However, our result is different than the two African studies conducted in Ghana and Tanzania which was 44% and 66% respectively [24,25]. The reason for the variation between our study (overall AR-positivity of 81%) and the Tanzanian study (overall AR-positivity of 66%) could be due to true biological difference in tumor characteristics in the two countries or methodological difference Table 2.…”

“…Only few studies have been conducted in Africa to characterize Androgen receptor (AR) in breast tumor. One of the study done among Tanzanians by Bravaccini et.al in 2018 [24] reported an overall frequency of AR-positivity at >1% cut-off value to be 66% and another done among Ghanaians by Proctor E et.al. in 2015 [25] reported an overall frequency of ARpositivity at >10% cut-off value to be 44%.…”

Androgen Receptor in Breast Cancer: From Bench to Bedside

“…AR can be detected in most BCs, and the frequency of its positivity differs between different BC subtypes and ethnicities ( 10 , 37 – 42 ). Numerous studies exploring the prognostic value of AR in BC have been presented with contentious results ( Table 1 ); in fact, the AR effect depends on tumor subtypes or patient populations.…”

Breast cancer pathology services in sub-Saharan Africa: a survey within population-based cancer registries

“…Most studies aim to reveal insight into tumour biology in Africa. There are reports from Ghana [ 28 , 29 ], the Republic of Congo [ 30 ], Kenya [ 31 ], Tanzania [ 32 , 33 ] and Ethiopia [ 34 ]. Some efforts were also made to publish results from established IHC services locally, with experiences reported from the Ivory Coast [ 35 ], Nigeria [ 36 ], Uganda [ 25 ], Angola [ 37 ], Ethiopia [ 38 ] and others.…”