Case Report: Grade 2 Metastatic Pancreatic Neuroendocrine Tumor With Progression of One Metastasis After Pregnancy to Grade 3 Large-Cell Neuroendocrine Carcinoma: One Case Cured by Resection With Genomic Characterization of the Two Components

Jean-Luc Raoul (1) , Marie-Françoise Heymann (1) , Frédéric Dumont (1) , Alain Morel (2) , Hélène Senellart (3) , F. Bertucci (4)

1 UNICANCER/ICO - Institut de Cancérologie de l'Ouest [Angers/Nantes]
2 CRCINA-ÉQUIPE 7 - Innate Immunity and Immunotherapy
3 Centre René Gauducheau
4 CRCM - Centre de Recherche en Cancérologie de Marseille

Temporal and spatial tumor heterogeneity can be observed in pancreatic neuroendocrine tumor. We report the case of a young woman with long term stabilization of a G2 metastatic pancreatic NET that, after pregnancy, suddenly progressed into one single liver metastasis corresponding to a transformation into G3 large-cell neuroendocrine cancer. The patient underwent liver resection (the progressive and one dormant metastasis). With a 45 months follow-up the patient is without evolutive disease. Exome sequencing of the two metastases revealed completely different genomic signatures and gene alterations: the dormant metastasis was MSS without any gene alteration; the poorly differentiated tumor was MSI, with gain of many mutations including MEN1, BCL2, MLH1 and TP53 corresponding to a mutational signature 11. Could temozolomide play a role in this transformation?

Keywords: sporadic gastrinoma; metastases; surgery; genomics; MEN 1 gene; microsatellite instability; MLH1

Domains: Cancer

Jean-Luc Raoul, Marie-Françoise Heymann, Frédéric Dumont, Alain Morel, Hélène Senellart, et al.. Case Report: Grade 2 Metastatic Pancreatic Neuroendocrine Tumor With Progression of One Metastasis After Pregnancy to Grade 3 Large-Cell Neuroendocrine Carcinoma: One Case Cured by Resection With Genomic Characterization of the Two Components. Frontiers in Oncology, 2021, 11, ⟨10.3389/fonc.2021.646992⟩. ⟨hal-03623095⟩