Abstract Library

#4666 Merkel cell neuroendocrine carcinoma of the skin: High response rates to short course palliative radiotherapy – Typical clinical scenarios

Introduction: Merkel cell carcinomas (MCC) are a rare, aggressive skin neuroendocrine carcinomas, with peak incidence in the elderly. MCC often presents as a firm, red/purple painless nodule with a short history of increasing size. Surgery is considered the 1st line treatment but elderly patients, in particular, have comorbidities which may preclude radical surgery requiring reconstruction. In advanced MCC, immunotherapy (IO) is 1st line systemic treatment. Chemotherapy is used 2nd line or if contraindications for IO but can be challenging in an elderly population. There may be an emerging role for PRRT due to the presence of somatostatin receptors on MCC. Radiotherapy (RT) can be used for non-surgical candidates, or those with unresectable or metastatic disease. Adjuvant post-operative irradiation (PORT) may provide additional benefit in risk reduction and improves local control.

Conference:

Presenting Author:

Authors: Saunders E, Sizer B, Collins J, Skelly R, Srinivasan G,

Keywords: Merkel cell, skin, radiotherapy,

#4657 Should we use the growth modulation index (GMI) in response assessment in G2 neuroendocrine tumours (NETs)?

Introduction: Grade 2 (G2) neuroendocrine tumours (NETs) exhibit diverse behaviours ranging from indolent to aggressive malignancies. Growth Modulation Index (GMI) is the ratio between time to progression (TTP) with a line of therapy (TTPn) and that of the previous line of therapy (TTPn-1). A GMI value equal to or greater than 1,33 has been suggested as an indicator of clinical effectiveness beyond traditional metrics.

Conference:

Presenting Author: Bertuzzi A

Authors: Bertuzzi A, Ferrillo G, Laffi A, Evangelista L, Jandric J,

Keywords: growth modulation index (GMI), G2 gastroenteropancreatic neuroendocrine tumour (GEP-NET), tumour response assessment,

#4625 Efficacy and safety of capecitabine-temozolomide (CAPTEM) regimen in patients with neuroendocrine neoplasms – A systematic review and experience from NETwerk, a Belgian ENETS Center of Excellence

Introduction: Current treatment guidelines remain inconclusive due to scarcity of data regarding the optimal systemic treatment for metastatic gastroenteropancreatic (GEP) neuroendocrine tumours (NET) grade 3 and aggressive GEP-NET grade 2. Similarly, for metastatic pulmonary typical (TC) and atypical carcinoids (AC), the indication for chemotherapy is unclear. Recent evidence highlights a promising role for CAPTEM, combining temozolomide (TEM) with capecitabine (CAP), showing encouraging antitumoural activity and safety profiles for these indications.

Conference:

Presenting Author: Chhajlani S

Authors: Chhajlani S, Lambrechts C, Islam O, de Weerdt C, Verbruggen L,

Keywords: capecitabine, temozolomide, CAPTEM, GEP-NET, pulmonary NEN, safety, efficacy, systematic review,

#4475 Retreatment with [177Lu]Lu-DOTATATE in neuroendocrine tumours: Outcomes in progression-free survival and toxicity – Our experience

Introduction: Multiple systemic treatments exist for advanced or metastatic NETs, including somatostatin analogues, targeted agents, chemotherapy, and peptide receptor radionuclide therapy (PRRT). PRRT has shown maximum benefit for response rate, progression-free survival (PFS), and overall survival (OS) with favourable toxicity.

Conference:

Presenting Author: Salcedo Cortes S

Authors: Salcedo Cortes S, Mari Hualde A, Ardila Manjarés E, Guzman Cruz A, Orcajo Rincón J,

Keywords: Neuroendocrine tumour (NET), Peptide receptor radionuclide therapy (PRRT), [177Lu]Lu-DOTATATE, Retreatment (R-PRRT), Toxicity, Progression-free survival (PFS), Overall survival (OS),

#4431 Systemic treatment in metastatic pheochromocytomas and paragangliomas: Optimal moment for starting and outcomes of a multicentre Spanish cohort

Introduction: Pheochromocytomas (PHEOs) and paragangliomas (PGLs), collectively referred to as PPGLs, are relatively rare endocrine tumours with significant clinical variability and metastatic behaviour. Treatment strategies must be tailored individually due to the heterogeneity in their behaviour.

Conference:

Presenting Author: Del Olmo-García M

Authors: Hernández-Rienda L, Contreras-Saldarriaga J, Hernando Cubero J, García Alvarez A, Prado-Wohlwend S,

Keywords: Pheochromocytoma, paraganglioma, PPGL, metastatic, SSA, Radionuclide, chemotherapy,