Real-world evidence of the management and prognosis of young women (⩽40 years) with de novo metastatic breast cancer

Amélie Mallet; Amélie Lusque; Christelle Levy; Barbara Pistilli; Etienne Brain; David Pasquier; Marc Debled; Jean Christophe Thery; Anthony Gonçalves; Isabelle Desmoulins; Thibault De La Motte Rouge; Christelle Faure; Jean Marc Ferrero; Jean Christophe Eymard; Marie Ange Mouret-Reynier; Anne Patsouris; Paul Cottu; Florence Dalenc; Thierry Petit; Olivier Payen; Lionel Uwer; Séverine Guiu; Jean Sébastien Frenel

doi:10.1177/17588359211070362

Real-world evidence of the management and prognosis of young women (⩽40 years) with de novo metastatic breast cancer

Ther Adv Med Oncol. 2022 Jan 21:14:17588359211070362. doi: 10.1177/17588359211070362. eCollection 2022.

Authors

Amélie Mallet¹, Amélie Lusque², Christelle Levy³, Barbara Pistilli⁴, Etienne Brain⁵, David Pasquier⁶, Marc Debled⁷, Jean Christophe Thery⁸, Anthony Gonçalves⁹, Isabelle Desmoulins¹⁰, Thibault De La Motte Rouge¹¹, Christelle Faure¹², Jean Marc Ferrero¹³, Jean Christophe Eymard¹⁴, Marie Ange Mouret-Reynier¹⁵, Anne Patsouris¹⁶, Paul Cottu¹⁷, Florence Dalenc¹⁸, Thierry Petit¹⁹, Olivier Payen²⁰, Lionel Uwer²¹, Séverine Guiu²², Jean Sébastien Frenel²³

Affiliations

¹ Department of Medical Oncology, Institut de Cancérologie de l'Ouest - René Gauducheau, Saint-Herblain, France.
² Department of Biostatistics, Institut Claudius Regaud - IUCT Oncopole, Toulouse, France.
³ Department of Medical Oncology, Centre François Baclesse, Caen, France.
⁴ Department of Cancer Medicine, Gustave Roussy, Villejuif, France.
⁵ Department of Medical Oncology, Institut Curie, Paris, France.
⁶ Department of Radiation Oncology, Centre Oscar Lambret, Lille, France.
⁷ Department of Medical Oncology, Institut Bergonie, Bordeaux, France.
⁸ Department of Medical Oncology, Centre Henri Becquerel, Rouen, France.
⁹ Department of Medical Oncology, Institut Paoli-Calmettes, Marseille, France.
¹⁰ Department of Medical Oncology, Centre Georges François Leclerc, Dijon, France.
¹¹ Department of Medical Oncology, Centre Eugène Marquis, Rennes, France.
¹² Department of Surgery Oncology, Centre Léon Bérard, Lyon, France.
¹³ Department of Medical Oncology, Centre Antoine Lacassagne, Nice, France.
¹⁴ Department of Medical Oncology, Institut de Cancérologie Jean-Godinot, Reims, France.
¹⁵ Department of Medical Oncology, Centre Jean Perrin, Clermont-Ferrand, France.
¹⁶ Department of Medical Oncology, Institut de Cancérologie de l'Ouest - Paul Papin, Angers, France.
¹⁷ Department of Medical Oncology, Etablissement Hospitalier Institut Curie, Paris, France.
¹⁸ Department of Medical Oncology, Institut Claudius Regaud - IUCT Oncopole, Toulouse, France.
¹⁹ Department of Medical Oncology, Centre Paul Strauss, Strasbourg, France.
²⁰ Department of Real World Data, Data Unit, Unicancer, Paris, France.
²¹ Department of Medical Oncology, Institut de Cancérologie de Lorraine, Vandœuvre-lès-Nancy, France.
²² Department of Medical Oncology, Institut du Cancer de Montpellier, Montpellier, France.
²³ Department of Medical Oncology, Institut de Cancérologie de l'Ouest - René Gauducheau, Boulevard Jacques Monod, 44805 Saint-Herblain, France.

Abstract

Background: Breast cancer (BC) in young women merits a specific approach given the associated fertility, genetic and psychosocial issues. De novo metastatic breast cancer (MBC) in young women is an even more serious condition, with limited data available.

Methods: We evaluated management of women aged ⩽40 years with de novo MBC in a real-life national multicentre cohort of 22,463 patients treated between 2008 and 2016 (NCT0327531). Our primary objective was to compare overall survival (OS) in young women versus women aged 41-69 years. The secondary objectives were to compare first-line progression-free survival (PFS1) and to describe treatment patterns.

Results: Of the 4524 women included, 598 (13%) were ⩽40 years. Median age at MBC diagnosis was 36 years (range = 20-40). Compared with women aged 41-69 years, young women had more grade III tumours (49% versus 35.7%, p < 0.0001), human epidermal growth factor receptor 2 amplified (HER2+) disease (34.6% versus 26.4%, p < 0.0001) and HR-/HER2- disease known as "triple negative breast cancer" (TNBC) (17.1% versus 12.7%, p < 0.0001). BRCA testing was performed for 260 young women, with a BRCA1/2 mutation in 44 (17% of those tested) In young HR+/HER2- patients, chemotherapy (CT) was given as the frontline treatment more frequently compared with older ones (89.6% versus 68.8%, respectively, p < 0.0001). After median follow-up of 49.7 months (95% confidence interval, CI = 48.0-51.7), the median OS of young women was 58.5 months, 20.7 months and not attained in HR+/HER2-, TNBC and HER2+ subgroups, respectively. After adjustment for histological subtype, tumour grade, and number and type of metastasis, young women had significantly better OS compared with older ones, except for the TNBC subgroup, for which the outcome was similar. PFS1 was statistically different only in the TNBC subgroup, with 7.8 months for young women and 6.3 months for older women (p = 0.0015).

Conclusion: De novo MBC affects a significant proportion of young women. A subgroup of these patients achieves long OS and merits multidisciplinary care.

Keywords: de novo; metastatic breast cancer; prognosis; real-life; young women.