Neoadjuvant Chemotherapy Response in Breast Cancer among Nigerian Women: A Systematic Review and Meta-Analysis (2000–2025)
Main Article Content
Keywords
Breast Cancer, Nigeria, Pathological complete response, Neoadjuvant chemotherapy, HER2, treatment outcomes
Abstract
Background: Neoadjuvant chemotherapy (NACT) is increasingly employed for locally advanced breast cancer in Nigeria, but treatment outcomes remain heterogeneous and often uncertain relative to global standards.
Methodology: We systematically reviewed Nigerian studies on NACT outcomes using PubMed, Embase, Scopus, Web of Science, AJOL, and grey literature through September 2025. Eligible studies included women receiving NACT who reported an objective response rate (ORR) or a pathologic complete response (pCR). Quality was assessed using ROBINS-I or RoB-2, and certainty was rated using GRADE. Pooled estimates were generated with random-effects (DerSimonian–Laird) models.
Results: Eleven studies (n = 629 women) met the inclusion criteria. Early anthracycline-based cohorts showed ORR = 51–93% with rare pCR. Contemporary anthracycline–taxane regimens achieved pCR ≈ 20%, the highest in HER2-positive and triple-negative disease. Pooled ORR = 66% (95% CI: 55–76%; I² = 46%) and pooled pCR = 20% (95% CI: 15–25%; I² = 39%). Excluding a non-standard single-agent trial raised pCR to 21%. The HER2-targeted ARETTA trial achieved pCR = 53%, approximating global benchmarks. Although one comparative study showed lower Nigerian pCR (5% vs 27% U.S.), survival appeared similar among patients completing multimodality therapy (observational finding). Certainty of evidence was rated low-to-moderate (GRADE).
Conclusions: NACT in Nigeria achieves consistent clinical downstaging but modest pCR outside HER2-targeted settings. Expanding access to biomarker testing, taxanes, trastuzumab (including biosimilars), and ensuring therapy completion are essential to close the global outcome gap.
References
2. Jedy-Agba E, McCormack V, Adebamowo PC, dos-Santos-Silva PI. Stage at diagnosis of breast cancer in sub-Saharan Africa: a systematic review and meta-analysis. Lancet Glob Health. 2016 Dec;4(12):e923.
3. Lm S, G F, A A, C S, R G, Kl R, et al. Pathologic Complete Response after Neoadjuvant Chemotherapy and Impact on Breast Cancer Recurrence and Survival: A Comprehensive Meta-analysis. Clin Cancer Res Off J Am Assoc Cancer Res [Internet]. 2020 June 15 [cited 2025 Sept 17];26(12). Available from: https://pubmed.ncbi.nlm.nih.gov/32046998/?utm_source=chatgpt.com
4. P C, L Z, M U, K M, Jp C, N W, et al. Pathological complete response and long-term clinical benefit in breast cancer: the CTNeoBC pooled analysis. Lancet Lond Engl [Internet]. 2014 July 12 [cited 2025 Sept 17];384(9938). Available from: https://pubmed.ncbi.nlm.nih.gov/24529560/?utm_source=chatgpt.com
5. L G, T P, Yh I, L R, Lm T, Mc L, et al. Efficacy and safety of neoadjuvant pertuzumab and trastuzumab in women with locally advanced, inflammatory, or early HER2-positive breast cancer (NeoSphere): a randomised multicentre, open-label, phase 2 trial. Lancet Oncol [Internet]. 2012 Jan [cited 2025 Sept 17];13(1). Available from: https://pubmed.ncbi.nlm.nih.gov/22153890/?utm_source=chatgpt.com
6. Gianni L, Eiermann W, Semiglazov V, Lluch A, Tjulandin S, Zambetti M, et al. Neoadjuvant and adjuvant trastuzumab in patients with HER2-positive locally advanced breast cancer (NOAH): follow-up of a randomised controlled superiority trial with a parallel HER2-negative cohort. Lancet Oncol. 2014 May;15(6):640–7.
7. Anyanwu SNC, Nwose P, Ihekwoaba E, Mbaeri AT, Chukwuanukwu TO. Neoadjuvant chemotherapy for locally advanced premenopausal breast cancer in Nigerian women: early experience. Niger J Clin Pract. 2010 June;13(2):215–7.
8. Arowolo OA, Akinkuolie AA, Lawal OO, Alatise OI, Salako AA, Adisa AO. The impact of neoadjuvant chemotherapy on patients with locally advanced breast cancer in a Nigerian semiurban teaching hospital: a single-center descriptive study. World J Surg. 2010 Aug;34(8):1771–8.
9. Egwuonwu OA, Anyanwu SN, Nwofor AM. Efficacy of neoadjuvant chemotherapy in down staging locally advanced pre-menopausal breast cancer in Eastern Nigeria: is four courses adequate? J Cancer Res Ther. 2013;9(4):638–43.
10. Samuel O, Olayide A, Ganiyu R, Olufemi H, Halimat A. Relationship between tumour size and response to neoadjuvant chemotherapy among breast cancer patients in a tertiary center in Nigeria. Malawi Med J. 2018 Mar;30(1):13–6.
11. Romanoff A, Olasehinde O, Goldman DA, Alatise OI, Constable J, Monu N, et al. Opportunities for Improvement in the Administration of Neoadjuvant Chemotherapy for T4 Breast Cancer: A Comparison of the U.S. and Nigeria. The Oncologist. 2021 Sept;26(9):e1589–98.
12. Olasehinde O, Omoyiola O, Aderounmu A, Olaofe O, Komolafe T, Omoyiola O, et al. Pathologic Complete Response Following Neoadjuvant Chemotherapy for Breast Cancer in a Nigerian Cohort : pCR post chemotherapy for breast cancer. Arch Breast Cancer. 2023 Sept 1;354–60.
13. Ntekim A, Popoola A, Sowunmi A, Olasehinde O, Sanni A, Ibraheem A, et al. Pragmatic Clinical Trial Assessing Response to Neoadjuvant Taxotere and Trastuzumab in Nigerian Women with Her2-Positive Breast Cancer (ARETTA): First Report from the Nigerian Breast Cancer Study Group [Internet]. Rochester, NY: Social Science Research Network; 2024 [cited 2025 Sept 17]. Available from: https://papers.ssrn.com/abstract=5058460
14. Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021 Mar 29;372:n71.
15. Eisenhauer EA, Therasse P, Bogaerts J, Schwartz LH, Sargent D, Ford R, et al. New response evaluation criteria in solid tumours: Revised RECIST guideline (version 1.1). Eur J Cancer. 2009 Jan 1;45(2):228–47.
16. Ouzzani M, Hammady H, Fedorowicz Z, Elmagarmid A. Rayyan—a web and mobile app for systematic reviews. Syst Rev. 2016 Dec 5;5(1):210.
17. Sterne JA, Hernán MA, Reeves BC, Savović J, Berkman ND, Viswanathan M, et al. ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions. BMJ. 2016 Oct 12;355:i4919.
18. Guyatt G, Oxman AD, Akl EA, Kunz R, Vist G, Brozek J, et al. GRADE guidelines: 1. Introduction-GRADE evidence profiles and summary of findings tables. J Clin Epidemiol. 2011 Apr;64(4):383–94.
19. Barendregt JJ, Doi SA, Lee YY, Norman RE, Vos T. Meta-analysis of prevalence. J Epidemiol Community Health. 2013 Nov 1;67(11):974–8.
20. DerSimonian R, Laird N. Meta-analysis in clinical trials. Control Clin Trials. 1986 Sept;7(3):177–88.
21. Egger M, Davey Smith G, Schneider M, Minder C. Bias in meta-analysis detected by a simple, graphical test. BMJ. 1997 Sept 13;315(7109):629–34.
22. Olukayode A Arowolo MB, Uchenna O Njiaju MD, Temidayo O Ogundiran MB, Oyewale Abidoye MB, Olukayode O Lawal MB, Millicent Obajimi M, et al. Neo-adjuvant Capecitabine Chemotherapy in Women with Newly Diagnosed Locally Advanced Breast Cancer in a Resource-poor Setting (Nigeria): Efficacy and Safety in a Phase II Feasibility Study. Breast J. 2013 July 19;19(5):470.
23. Advani P, Cornell L, Chumsri S, Moreno-Aspitia A. Dual HER2 blockade in the neoadjuvant and adjuvant treatment of HER2-positive breast cancer. Breast Cancer Targets Ther. 2015 Sept 22;7:321.
24. Schneeweiss A, Chia S, Hickish T, Harvey V, Eniu A, Waldron-Lynch M, et al. Long-term efficacy analysis of the randomised, phase II TRYPHAENA cardiac safety study: Evaluating pertuzumab and trastuzumab plus standard neoadjuvant anthracycline-containing and anthracycline-free chemotherapy regimens in patients with HER2-positive early breast cancer. Eur J Cancer. 2018 Jan 1;89:27–35.
25. Schmid P, Cortes J, Dent R, Pusztai L, McArthur H, Kümmel S, et al. Event-free Survival with Pembrolizumab in Early Triple-Negative Breast Cancer. N Engl J Med. 2022 Feb 9;386(6):556–67.
26. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Increasing the dose intensity of chemotherapy by more frequent administration or sequential scheduling: a patient-level meta-analysis of 37 298 women with early breast cancer in 26 randomised trials. Lancet Lond Engl. 2019 Apr 6;393(10179):1440–52.
27. WHO prequalifies first biosimilar medicine to increase worldwide access to life-saving breast cancer treatment [Internet]. [cited 2025 Sept 18]. Available from: https://www.who.int/news/item/18-12-2019-who-prequalifies-first-biosimilar-medicine-to-increase-worldwide-access-to-life-saving-breast-cancer-treatment
28. Ishibashi Y, Hirano A, Yukawa H, Kitano A, Kodera A, Fujita S, et al. [Adjuvant Capecitabine for Residual Disease after Standard Neoadjuvant Chemotherapy Among Patients with Triple-Negative Breast Cancer]. Gan To Kagaku Ryoho. 2022 Dec;49(13):1461–3.
29. Masuda N, Lee SJ, Ohtani S, Im YH, Lee ES, Yokota I, et al. Adjuvant Capecitabine for Breast Cancer after Preoperative Chemotherapy. N Engl J Med. 2017 June 1;376(22):2147–59.
30. Mamounas EP, Untch M, Mano MS, Huang CS, Geyer CE, von Minckwitz G, et al. Adjuvant T-DM1 versus trastuzumab in patients with residual invasive disease after neoadjuvant therapy for HER2-positive breast cancer: subgroup analyses from KATHERINE. Ann Oncol Off J Eur Soc Med Oncol. 2021 Aug;32(8):1005–14.
Article Sidebar
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This is an open-access journal and articles are distributed under the terms of the Creative Commons Attribution Non-Commercial Share-Alike License 4.0. This licence allows users to download and share, remix, tweak and build upon the article for non-commercial purposes, so long as the original authorship is acknowledged and the new creations are licensed under identical terms.