Evolution of synchronous female bilateral breast cancers and response to treatment

Nom de la revue
Nature Medicine
Anne-Sophie Hamy, Judith Abécassis, Keltouma Driouch, Lauren Darrigues, Mathias Vandenbogaert, Cecile Laurent, Francois Zaccarini, Benjamin Sadacca, Myriam Delomenie, Enora Laas, Odette Mariani, Thanh Lam, Beatriz Grandal, Marick Laé, Ivan Bieche, Sophie Vacher, Jean-Yves Pierga, Etienne Brain, Celine Vallot, Judicael Hotton, Wilfrid Richer, Dario Rocha, Zakia Tariq, Veronique Becette, Didier Meseure, Laetitia Lesage, Anne Vincent-Salomon, Natalie Filmann, Jenny Furlanetto, Sibylle Loibl, Elise Dumas, Joshua J. Waterfall, Fabien Reyal

AbstractSynchronous bilateral breast cancer (sBBC) occurs after both breasts have been affected by the same germline genetics and environmental exposures. Little evidence exists regarding immune infiltration and response to treatment in sBBCs. Here we show that the impact of the subtype of breast cancer on levels of tumor infiltrating lymphocytes (TILs, n = 277) and on pathologic complete response (pCR) rates (n = 140) differed according to the concordant or discordant subtype of breast cancer of the contralateral tumor: luminal breast tumors with a discordant contralateral tumor had higher TIL levels and higher pCR rates than those with a concordant contralateral tumor. Tumor sequencing revealed that left and right tumors (n = 20) were independent regarding somatic mutations, copy number alterations and clonal phylogeny, whereas primary tumor and residual disease were closely related both from the somatic mutation and from the transcriptomic point of view. Our study indicates that tumor-intrinsic characteristics may have a role in the association of tumor immunity and pCR and demonstrates that the characteristics of the contralateral tumor are also associated with immune infiltration and response to treatment.