Abstract 3518: Pilot study of prostate cancer survival among African patients in the Men of African Descent and Cancer of the Prostate (MADCaP) Consortium
Authors: Agalliu Ilir , Andrews Caroline , Adebiyi Akindele Olupelumi , Jalloh Mohamed , Joffe Maureen , Rebbeck Timothy R. , Hsing Ann 
Published: September 2020

Introduction: Men of African descent have the highest burden of aggressive and lethal prostate cancer (PrCa). In Sub-Saharan Africa (SSA), PrCa accounts for 19% of all cancer-related deaths. However, there has been no large-scale PrCa survival studies in SSA. The objective of this study was to assess the feasibility of establishing a PrCa survival cohort in SSA, ascertain vital status and cause of death, determine willingness of PrCa patients to participate and evaluate feasibility of collecting tumor tissues and extract RNA.

Methods: A total of 137 PrCa patients, who were initially enrolled in an ongoing PrCa genetic study across seven hospitals in West and South Africa (U01CA184374) in the MADCaP consortium, were followed from their cancer diagnosis and enrollment into the main study through date of death, date of last contact or end of follow-up: 12/31/2018. Follow-up was carried out by direct phone contact of patients and/or their next-of-kin and by reviewing medical records of follow-up hospital visits. PrCa patients alive at contact were invited to participate into the pilot study and completed a brief survey to assess their general health and symptoms as well as quality of life. Formalin-fixed, paraffin-embedded (FFPE) PrCa tissues from 20 patients were retrieved from pathology departments of four hospitals in West Africa. RNA extraction from tumor tissues was carried out using the Qiagen RNeasy® FFPE Kit in the Molecular Cytogenetic Core at Einstein (USA).

Results: The average age of 137 PrCa patients was 68 years old (range 40-88), 70 (51%) and 41 (30%) of them were diagnosed with a Gleason score 8-10 cancer, or advanced tumor stage (T3/T4), and the median PSA at diagnosis was 100 ng/ml. Majority of patients received either radiation or hormone deprivation therapy; although there was variability across centers. During an average 20.3 months of follow-up, a total of 29 (21%) patients had died, and 23 (17%) were lost to follow-up; 69% of deaths were due to PrCa. Interestingly the majority of patients who died (62%) and those lost to follow-up (61%) had Gleason score 8-10 cancer. Among PrCa patients alive (N=85) at contact, 95% agreed to participate in the pilot study and completed the protocol. The median RNA yield of tumor samples was 645 ng (range 280-1,820 ng).

Conclusions: This feasibility study demonstrated the ability to follow-up PrCa patients across several hospitals in West and South Africa and highlighted the advanced clinical characteristics of PrCa and relatively low survival among African men in SSA. Tumor samples also yielded sufficient RNA that can be used for molecular studies. Larger studies are needed to better understand the clinical and epidemiological risk factors for PrCa survival in SSA and to develop strategies to address survival bias and lost to follow-up. Studies of PrCa survival in Africa might also contribute to better understanding of PrCa racial disparities in the USA.

Citation Format: Ilir Agalliu, Caroline Andrews, Akindele Olupelumi Adebiyi, Mohamed Jalloh, Maureen Joffe, Timothy R. Rebbeck, Ann Hsing. Pilot study of prostate cancer survival among African patients in the Men of African Descent and Cancer of the Prostate (MADCaP) Consortium [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3518.