Background: Luminal A-like and luminal B-like subtypes have different sensitivity to (neo)adjuvant chemotherapy, but their role in predicting dose-dense (DD) efficacy in the high-risk setting is unknown. In this exploratory analysis of the Gruppo Italiano Mammella 2 (GIM2) trial, we investigated DD efficacy according to luminal-like subtypes. Methods: Patients with node-positive early breast cancer were randomised to receive either DD or standard-interval (SI) anthracycline-based chemotherapy followed by paclitaxel. In our analysis, luminal A-like cohort was identified as having a Ki67 < 20% and a progesterone receptor (PgR) ≥ 20%; luminal B-like cohort as having a Ki67 ≥ 20% and/or a PgR < 20%. Results: Out of 2003 patients enrolled in the GIM2 trial, 412 had luminal A-like and 638 luminal B-like breast cancer. After a median follow-up of 7.9 years, disease-free survival (DFS) was 80.8% (95% confidence interval [CI] 76.4–84.5) and 70.5% (66.5–74.2) in luminal A-like and luminal B-like cohorts; overall survival (OS) was 91.6% (88.2–94.1) and 85.1% (81.7–87.9), respectively. We found no significant interaction between treatment and luminal subtype (interaction p = 0.603 and 0.535 for DFS and OS, respectively). When DD efficacy was investigated separately in each cohort, luminal-B like cohort appeared to benefit more from the DD schedule both in terms of DFS (unadjusted hazard ratio [HR] 0.72 [95% CI 0.54–0.96]) and OS (unadjusted HR 0.61 [95% CI 0.40–0.94]), compared with the luminal A-like cohort (unadjusted HR for DFS 0.89 [95% CI 0.59–1.33]; unadjusted HR for OS 0.83 [95% CI 0.45–1.54]). Conclusions: No significant interaction between luminal-like subtype and treatment was observed. Patients in the luminal B-like cohort seemed to benefit more from DD schedule.

Effect of dose-dense adjuvant chemotherapy in hormone receptor positive/HER2-negative early breast cancer patients according to immunohistochemically defined luminal subtype: an exploratory analysis of the GIM2 trial / Conte, B.; Bruzzone, M.; Lambertini, M.; Poggio, F.; Bighin, C.; Blondeaux, E.; De Laurentiis, M.; Valle, E.; Cognetti, F.; Nistico, C.; De Placido, S.; Garrone, O.; Gamucci, T.; Montemurro, F.; Puglisi, F.; Cardinali, B.; Fregatti, P.; Miglietta, L.; Boccardo, F.; Ceppi, M.; Del Mastro, L.. - In: EUROPEAN JOURNAL OF CANCER. - ISSN 0959-8049. - 136:(2020), pp. 43-51. [10.1016/j.ejca.2020.05.007]

Effect of dose-dense adjuvant chemotherapy in hormone receptor positive/HER2-negative early breast cancer patients according to immunohistochemically defined luminal subtype: an exploratory analysis of the GIM2 trial

Conte B.;Lambertini M.;De Laurentiis M.;De Placido S.;
2020

Abstract

Background: Luminal A-like and luminal B-like subtypes have different sensitivity to (neo)adjuvant chemotherapy, but their role in predicting dose-dense (DD) efficacy in the high-risk setting is unknown. In this exploratory analysis of the Gruppo Italiano Mammella 2 (GIM2) trial, we investigated DD efficacy according to luminal-like subtypes. Methods: Patients with node-positive early breast cancer were randomised to receive either DD or standard-interval (SI) anthracycline-based chemotherapy followed by paclitaxel. In our analysis, luminal A-like cohort was identified as having a Ki67 < 20% and a progesterone receptor (PgR) ≥ 20%; luminal B-like cohort as having a Ki67 ≥ 20% and/or a PgR < 20%. Results: Out of 2003 patients enrolled in the GIM2 trial, 412 had luminal A-like and 638 luminal B-like breast cancer. After a median follow-up of 7.9 years, disease-free survival (DFS) was 80.8% (95% confidence interval [CI] 76.4–84.5) and 70.5% (66.5–74.2) in luminal A-like and luminal B-like cohorts; overall survival (OS) was 91.6% (88.2–94.1) and 85.1% (81.7–87.9), respectively. We found no significant interaction between treatment and luminal subtype (interaction p = 0.603 and 0.535 for DFS and OS, respectively). When DD efficacy was investigated separately in each cohort, luminal-B like cohort appeared to benefit more from the DD schedule both in terms of DFS (unadjusted hazard ratio [HR] 0.72 [95% CI 0.54–0.96]) and OS (unadjusted HR 0.61 [95% CI 0.40–0.94]), compared with the luminal A-like cohort (unadjusted HR for DFS 0.89 [95% CI 0.59–1.33]; unadjusted HR for OS 0.83 [95% CI 0.45–1.54]). Conclusions: No significant interaction between luminal-like subtype and treatment was observed. Patients in the luminal B-like cohort seemed to benefit more from DD schedule.
2020
Effect of dose-dense adjuvant chemotherapy in hormone receptor positive/HER2-negative early breast cancer patients according to immunohistochemically defined luminal subtype: an exploratory analysis of the GIM2 trial / Conte, B.; Bruzzone, M.; Lambertini, M.; Poggio, F.; Bighin, C.; Blondeaux, E.; De Laurentiis, M.; Valle, E.; Cognetti, F.; Nistico, C.; De Placido, S.; Garrone, O.; Gamucci, T.; Montemurro, F.; Puglisi, F.; Cardinali, B.; Fregatti, P.; Miglietta, L.; Boccardo, F.; Ceppi, M.; Del Mastro, L.. - In: EUROPEAN JOURNAL OF CANCER. - ISSN 0959-8049. - 136:(2020), pp. 43-51. [10.1016/j.ejca.2020.05.007]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11588/844151
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 8
  • ???jsp.display-item.citation.isi??? 7
social impact