CRC peaks during the fifth decade of life in Kenyans. The disease is characterized by late presentation, rectal preponderance, and inadequate pathology data. Improved patient follow-up will unravel the true pattern of disease outcome.

Purpose There are no published data from specific regions of sub-Saharan Africa describing the clinical and pathological characteristics and molecular subtypes of invasive breast cancer by ethnic group. The purpose of this study was to investigate these characteristics among the three major ethno-cultural groupings in Kenya. Methods The study included women with pathologically-confirmed breast cancer seen between March 2012 and May 2015 at 11 hospitals throughout Kenya. Socio-demographic, clinical, and reproductive data were collected by questionnaire, and pathology review and immunohistochemistry were performed centrally. Results The 846 cases included 661 Bantus (78.1%), 143 Nilotes (16.9%), 19 Cushites (2.3%), and 23 patients of mixed ethnicity (2.7%). In analyses comparing the two major ethnic groups, Bantus were more educated, more overweight, had an older age at first birth and had a younger age at menopause than Nilotes (p<0.05 for all comparisons). In analyses restricted to definitive surgery specimens, there were no statistically significant differences in tumour characteristics or molecular subtypes, although the Nilote tumours tended to be larger (OR for ≥ 5 cm vs. < 2 cm: 3.86, 95%CI: 0.77, 19.30) and were somewhat more likely to be HER2-enriched (OR for HER2-enriched vs. Luminal A/B: 1.41, 95%CI: 0.79, 2.49). Conclusion This case series showed no significant differences in breast cancer tumour characteristics or molecular subtypes, but significant differences in socio-demographic characteristics and reproductive factors, among the three major ethnic groups in Kenya. We suggest further evaluation of ethnic differences in breast cancer throughout the genetically and culturally diverse populations of sub-Saharan Africa.

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Use of the MTT for diagnosis of palpable breast masses in young women (