Immune checkpoint inhibitors for patients with metastatic triple-negative inflammatory breast cancer (INCORPORATE): an international cohort study
Menée dans un contexte de vie réelle à partir de données portant sur 41 patientes atteintes d'un cancer inflammatoire du sein triple négatif et de stade métastatique (durée médiane de suivi : 19,3 mois), cette étude de cohorte internationale évalue l'efficacité, du point de vue de la survie sans progression à 6 mois, de l'ajout d'inhibiteurs de point de contrôle immunitaire à une chimiothérapie de première ligne
Résumé en anglais
Background: Inflammatory breast cancer (IBC) is the most aggressive clinical presentation of breast cancer, recapitulating a specific biology with more immune-vulnerability than non-IBC. Patients with metastatic, triple-negative IBC (mTN-IBC) receive immune checkpoint inhibitors (ICIs) and chemotherapy, similarly to patients with triple-negative non-IBC. However, the benefit derived from ICI incorporation in this rare type of breast cancer is unknown.
Methods: We conducted a multicenter, international, retrospective, cohort study to evaluate the activity of ICIs in patients with metastatic, triple-negative, primary IBC, who received ICIs plus first line chemotherapy from January 2015 to April 2023. A sample size of 42 patients allowed to detect an increase in 6-months real-world progression-free survival (rwPFS) rate from 40% with only chemotherapy to 60% with ICI and chemotherapy.
Results: 41 patients from eight international IBC referral centers were included (61% with primary, de novo mTN-IBC, 61% with visceral disease). All received ICIs plus first line chemotherapy and 24% underwent breast surgery and/or locoregional radiotherapy. After a median follow-up of 19.3 months, the 6-months rwPFS rate was 30% (95% Confidence Interval [CI], 17-45%), the median rwPFS was 3.3 months (95% CI: 2.2-5.4), the median overall survival was 15.7 months (95% CI: 6.8-16.3).
Conclusions: This one-sample analysis showed a poor outcome of patients with mTN-IBC, despite the treatment with ICI, in contrast with the expected benefit based on preclinical evidence of immune-vulnerability of IBC. These results suggest the need to further investigate the role of immunotherapy in this aggressive and rare type of breast cancer presentation.
