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,

#4652 Clinical response to somatostatin analogues in patients with DIPNECH: Findings from a new longitudinal registry

Introduction: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) often presents with symptoms of cough and dyspnoea. DIPNECH remains understudied, and response to somatostatin analogues (SSAs) has been reported in a few small series.

Conference:

Presenting Author: Libre M

Authors: Libre M, Skotte E, Linden A, Wu J, Lippincott E,

Keywords: DIPNECH, somatostatin analogue,

#4646 Dysregulated miRNA in patients with GEP-NEN and potential role as circulating biomarker

Introduction: Neuroendocrine neoplasms (NENs) are a class of rare and molecularly extremely heterogeneous tumours. NENs arise predominantly in the gastrointestinal (GEP) and pulmonary tracts but can also involve thyroid and breast. NENs often present with non-specific symptoms and lack early specific biomarkers, leading to frequent metastatic diagnoses and primary site challenges.

Conference:

Presenting Author:

Authors: Di Mauro A, Clemente O, Cannella L, Della Vittoria G, Neri G,

Keywords: neuroendocrine tumour, miRNome profiling, biomarker, gep-net, molecular biology,

#4643 Characterisation of patients with progressive digestive NET during PRRT (LUTA-CHEC): A multicentre study from the Groupe des Tumeurs Endocrines

Introduction: PRRT with 177Lu-DOTATATE is a major treatment for metastatic digestive NETs. Most patients have prolonged progression-free survival, but around 20% experience early progression.

Conference:

Presenting Author: Haissaguerre M

Authors: Haissaguerre M, Hadoux J, Tlili G, Deshayes E, Lacombe M,

Keywords: GEP-NET, PRRT, early tumour progression,