Abstract
Introduction
Triple-negative breast cancer (TNBC), known for its particularly aggressive nature, is associated with a poor prognosis. Tumour-infiltrating lymphocytes (TILs) are emerging as a key prognostic biomarker in this subtype.
Purpose
To quantitatively analyse TILs and explore their association with clinical and pathological characteristics among Congolese patients.
Methods
A cross-sectional, descriptive study was conducted between January 2022 and December 2024 in two reference cytopathology laboratories in Kinshasa (University Clinics and LEBOMA Pathology Cabinet). A convenience sample of 147 breast cancer patients was included, of whom 28 had triple-negative breast cancer confirmed by immunohistochemistry. Data were extracted using Microsoft Excel 2016 and analysed with SPSS version 27. Proportion comparisons were performed using the chi-square test, with statistical significance set at p < 0.05.
Results
Among the 147 breast cancer patients included, 28 (19.05%) had TNBC. The intermediate TIL group was the most represented (39.3%), predominantly associated with grade 3 tumours, followed by the low TIL group (35%), where grade 2 tumours predominated (60%). The age group ≤ 50 years accounted for 19 patients (67.9%), among whom 9 (47.3%; 95% CI [27.3–68.3]) had intermediate TILs. A low degree of TILs was observed in 6 patients (66.7%) aged > 50 years. A Ki-67 proliferative index > 30% was noted in 21 patients (75%), of whom 10 (47.6%; 95% CI [28.3–67.6]) had intermediate TILs.
Conclusion
The majority of TNBC patients had TIL levels ≥10. High TIL density was associated with younger age and a lower Ki-67 proliferation index. TIL assessment therefore emerges as a relevant prognostic biomarker that could guide patient follow-up and therapeutic decision-making, particularly regarding immunotherapy.
References
Amasa, P. J. I., Azama, M. S., Tshofu, E. D., Okitokonda, F. D., Lenga, S. L., Kalunda, É. P., & Loshima, E. O. (2024). Results of breast cancer knowledge among Congolese women in Kinshasa: A cross-sectional study. PAMJ Clinical Medicine, 14(13). https://doi.org/10.11604/pamj-cm.2024.14.13.41634
Bray, F., Ferlay, J., Soerjomataram, I., Siegel, R. L., Torre, L. A., & Jemal, A. (2018). Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA: A Cancer Journal for Clinicians, 68(6), 394–424. https://doi.org/10.3322/caac.21492
Bray, F., Laversanne, M., Sung, H., Ferlay, J., Siegel, R. L., Soerjomataram, I., & Jemal, A. (2024). Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA: A Cancer Journal for Clinicians, 74(3), 229–263. https://doi.org/10.3322/caac.21834
Bray, F., Parkin, D. M., & African Cancer Registry Network. (2022). Cancer in sub-Saharan Africa in 2020: A review of current estimates of the national burden, data gaps, and future needs. The Lancet Oncology, 23(6), 719–728. https://doi.org/10.1016/S1470-2045(22)00270-4
Campedel, L., Blanc-Durand, P., Bin Asker, A., Lehmann-Che, J., Cuvier, C., De Bazelaire, C., … Cottu, P. (2020). Prognostic impact of stromal immune infiltration before and after neoadjuvant chemotherapy (NAC) in triple negative inflammatory breast cancers (TNIBC) treated with dose-dense dose-intense NAC. Cancers, 12(9), 2657. https://doi.org/10.3390/cancers12092657
De Jong, V. M. T., Wang, Y., Ter Hoeve, N. D., Opdam, M., Stathonikos, N., Jóźwiak, K., … van Diest, P. J. (2022). Prognostic value of stromal tumor-infiltrating lymphocytes in young, node-negative, triple-negative breast cancer patients who did not receive (neo)adjuvant systemic therapy. Journal of Clinical Oncology, 40(21), 2361–2374. https://doi.org/10.1200/JCO.21.01536
Denkert, C., von Minckwitz, G., Darb-Esfahani, S., Lederer, B., Heppner, B. I., Weber, K. E., … Loibl, S. (2018). Tumour-infiltrating lymphocytes and prognosis in different subtypes of breast cancer: A pooled analysis of 3771 patients treated with neoadjuvant therapy. The Lancet Oncology, 19(1), 40–50. https://doi.org/10.1016/S1470-2045(17)30904-X
DeSantis, C. E., Ma, J., Gaudet, M. M., Newman, L. A., Miller, K. D., Goding Sauer, A., … Jemal, A. (2019). Breast cancer statistics, 2019. CA: A Cancer Journal for Clinicians, 69(6), 438–451. https://doi.org/10.3322/caac.21583
Feng, J., Li, J., Huang, X., Yi, J., Wu, H., Zou, X., … Xie, X. (2021). Nomogram to predict tumor-infiltrating lymphocytes in breast cancer patients. Frontiers in Molecular Biosciences, 8, 761163. https://doi.org/10.3389/fmolb.2021.761163
Giaquinto, A. N., Sung, H., Newman, L. A., Freedman, R. A., Smith, R. A., Star, J., … Siegel, R. L. (2024). Breast cancer statistics 2024. CA: A Cancer Journal for Clinicians, 74(6), 477–495. https://doi.org/10.3322/caac.21863
Gnangnon, F. (2024). Contribution à la connaissance du fardeau et des facteurs pronostiques du cancer du sein au Bénin et en Afrique au Sud du Sahara [Doctoral thesis, Université de Limoges & Université d’Abomey-Calavi]. HAL. https://theses.hal.science/tel-04921380
Goronzy, J. J., & Weyand, C. M. (2009). The ageing immune system. Nature Reviews Immunology, 9(12), 850–860. https://doi.org/10.1038/nri2674
Grivennikov, S. I., Greten, F. R., & Karin, M. (2010). Inflammation and cancer: An ancient link with new paradigms. Cell, 140(6), 883–899. https://doi.org/10.1016/j.cell.2010.01.038
Loi, S., Michiels, S., Salgado, R., Sirtaine, N., Jose, V., Fumagalli, D., … Piccart, M. (2014). Tumor infiltrating lymphocytes are prognostic in triple negative breast cancer and predictive for trastuzumab benefit in early breast cancer: Results from the FinHER trial. Annals of Oncology, 25(8), 1544–1550. https://doi.org/10.1093/annonc/mdu112
Loibl, S., Schneeweiss, A., Huober, J., Braun, M., Rey, J., Blohmer, J.-U., … von Minckwitz, G. (2022). Neoadjuvant durvalumab improves survival in early triple-negative breast cancer independent of pathological complete response. Annals of Oncology, 33(11), 1149–1158. https://doi.org/10.1016/j.annonc.2022.07.1940
Maseb’a Mwang Sulu, S., Batalansi, D. B., Sulu, A. M. S., Mukuku, O., Mboloko, J. E., Mashinda, D. K., … Tshibassu, P. M. (2022). Immunohistochemical features of breast cancer seen in women in Kinshasa, Democratic Republic of the Congo: A six-year retrospective study. International Journal of Breast Cancer, 2022, 8860947. https://doi.org/10.1155/2022/8860947
Mashinda, D. K., Kayembe, K., & Mapatano, M. (2012, June 27). Cancer prevalence in the Democratic Republic of the Congo: Anatomopathologic data collected at the Cliniques Universitaires and Hôpital Général de Référence de Kinshasa. Annales africaines de médecine. https://anafrimed.net/prevalence-du-cancer-en-republique-democratique-du-congo
Natacha, J., Kordahi, M., Blanc-Fournier, C., & Lacroix-Triki, M. (n.d.). Assessment of tumor-infiltrating lymphocytes in breast cancers: How to apply international recommendations 2014. EM-Consulte. Retrieved July 16, 2025, from https://www.em-consulte.com/article/1104396/evaluation-des-lymphocytes-infiltrant-la-tumeur
Ngwala, P. L., Ngangu, P. N., Diakengua, V., Kalombo, C., Nyambu, J., Landu, J., … Kayembe, P. (n.d.). Epidemiology of cancer in rural Congo: Case of IME Kimpese Hospital, Democratic Republic of Congo. Open Journal of Epidemiology. https://www.scirp.org/journal/paperinformation?paperid=107856
Salgado, R., Denkert, C., Demaria, S., Sirtaine, N., Klauschen, F., Pruneri, G., Wienert, S., ... Loi, S. (2015). The evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer: Recommendations by an International TILs Working Group 2014. Annals of Oncology, 26(2), 259–271. https://doi.org/10.1093/annonc/mdu450
Santhanam, R., Bains, S. L., An, M., & Al-Hajj, M. (2018). Age-related changes in the tumour microenvironment and their impact on tumour immunity. Journal of Hematology & Oncology, 11(1), 108. https://doi.org/10.1186/s13045-018-0648-z
Takada, K., Kashiwagi, S., Asano, Y., Goto, W., Morisaki, T., Shibutani, M., … Hirakawa, K. (2022). Differences in tumor-infiltrating lymphocyte density and prognostic factors for breast cancer by patient age. World Journal of Surgical Oncology, 20(1), 38. https://doi.org/10.1186/s12957-022-02513-5
Wang, Y., Zong, B., Yu, Y., Wang, Y., Tang, Z., Chen, R., … Zhang, Y. (2021). Ki67 index changes and tumor-infiltrating lymphocyte levels impact the prognosis of triple-negative breast cancer patients with residual disease after neoadjuvant chemotherapy. Frontiers in Oncology, 11, 668610. https://doi.org/10.3389/fonc.2021.668610
World Health Organization. (n.d.). Breast cancer. Retrieved July 15, 2025, from https://www.who.int/news-room/fact-sheets/detail/breast-cancer
Zhu, X., Chen, L., Huang, B., Wang, Y., Ji, L., Wu, J., … Chen, X. (2020). The prognostic and predictive potential of Ki-67 in triple-negative breast cancer. Scientific Reports, 10(1), 225. https://doi.org/10.1038/s41598-019-57094-3
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