Abstract Library

#4459 Sequential alkylating therapy and pembrolizumab induce near-complete response in high tumour mutational burden pancreatic neuroendocrine tumour: A case report

Introduction: Traditional treatment for neuroendocrine tumours (NETs), including surgery, somatostatin therapy, and targeted therapy, often fails in advanced disease. Alkylating therapy can increase tumour mutational burden (TMB), and the recent KEYNOTE-158 study approved pembrolizumab for advanced solid tumours with a high TMB.

Conference:

Presenting Author:

Authors: Paranjpe I, Hornbacker K, Vadde S, Fisher G, Shaheen S,

Keywords: pancreatic neuroendocrine tumour, immunotherapy, pembrolizumab, tumour mutational burden, TMB,

#4417 Efficacy of immune checkpoint inhibitors (ICI) in patients with advanced pancreatic NETs displaying high TMB and MMR alterations following treatment with alkylating agents

Introduction: Alkylating chemotherapy (ALK) is frequently used in patients with PanNETs. It may favour grade progression and acquisition of a hypermutator phenotype associated with frequent alterations of the MMR genes, suggesting a potential benefit of ICI.

Conference:

Presenting Author:

Authors: de Mestier L, Apostolidis L, Koumarianou A, Hernando Cubero J, Riechelmann R,

Keywords: immune checkpoint inhibitor, immunotherapy, hypermutagenicity, alkylating agents, tumour mutational burden, mismatch repair,

#4103 The evolutionary history of metastatic pancreatic neuroendocrine tumors reveals a therapy driven route to high-grade transformation

Introduction: Tumor evolution with acquisition of more aggressive disease characteristics is a hallmark of disseminated cancer. Metastatic pancreatic neuroendocrine tumors (PanNETs) in particular, show frequent progression from a low/intermediate to a high-grade disease.

Conference:

Presenting Author: Crona J

Authors: Backman S, Botling J, Nord H, Ghosal S, Stålberg P,

Keywords: Pancreatic neuroendocrine tumor, Tumor evolution, Alkylating chemotherapy, Treatment resistance,

#3555 Risk of myelodysplastic syndrome/acute leukemia with sequential capecitabine/temozolomide and 177Lu-dotatate

Introduction: The treatment landscape for neuroendocrine tumors includes alkylating-agent chemotherapy and peptide receptor radiotherapy (PRRT) with 177Lu-Dotatate. The risk of MDS/AML associated with 177Lu-Dotatate is approximately 2-3%. Several small prior studies have suggested substantially higher rates of MDS/AML (approximately 10%) in patients who have also received alkylating agent chemotherapy with streptozocin or temozolomide, either combined with PRRT or sequentially.

Conference:

Presenting Author:

Authors: Al-Toubah T, Pelle E, Strosberg J,

Keywords: captem, PRRT, mds, aml,