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,

#4601 Pembrolizumab combined with cisplatin or carboplatin and etoposide in treatment naïve advanced Merkel cell carcinoma (MCC): The phase II PANDORA Trial

Introduction: MCC is a rare and aggressive skin neuroendocrine tumour with high metastatic potential and mortality. Therapeutic options in metastatic/unresectable MCC are based on immunotherapy or platinum-based chemotherapy. However, a subgroup of patients (pts) has primary immunoresistance disease, so it would be important discover active upfront combinations. PANDORA trial [NCT 06086288] is an open-label, multicentre, single-arm phase II trial evaluating the activity and safety of pembrolizumab (PEM) combined with platinum-based chemotherapy as 1st line treatment in pts with metastatic, unresectable or recurrence MCC. Supported in part by a research grant from Investigator-Initiated Studies Program of MSD.

Conference:

Presenting Author: Oldani S

Authors: Oldani S, Morano F, Cingarlini S, Di Giacomo A, Borghesani M,

Keywords: Pembrolizumab, clinical trial, Merkel cell carcinoma, chemio-immunotherapy,

#3492 The first circulating tumor cell-derived explant (CDX) model of a Merkel cell carcinoma

Introduction: Poorly differentiated ExtraPulmonary NeuroEndocrine Carcinomas (EP-NECs) have a median overall survival of

Conference:

Presenting Author: Frizziero M

Authors: Frizziero M, Kilgour E, Simpson K, Rothwell D, Frese K,

Keywords: neuroendocrine carcinoma, Merkel cell carcinoma, circulating tumor cell, mouse model,

#3304 Ga-68/Lu-177 octreotate theranostic paradigm in metastatic Merkel cell carcinoma

Introduction: Merkel cell carcinoma (MCC) is a rare, aggressive, cutaneous neuroendocrine tumor with poor survival and significant propensity for metastasising. MCC is normally characterised by an up-regulation of somatostatin receptors (SSTR) which introduces the possibility for a targeted treatment approach using peptide receptor radionuclide therapy (PRRT).

Conference: 18th Annual ENETS Concerence (2021)

Presenting Author: Lenzo N

Authors: Falzone N, Meyrick D, Lee B, Lenzo N,

Keywords: peptide receptor radionuclide therapy, Merkel cell carcinoma, Lu-177 octreotate, Ac-225 octreotate,

#3289 Short-interval, low-dose (SILD) Lu-177 DOTAiTATE therapy to overcome resistance to immunotherapy with PD-1 checkpoint inhibitors: Proof of concept to induce remission in patients with metastatic Merkel cell carcinoma and melanoma

Introduction: Immunotherapy with PD-1 immune checkpoint inhibitors (ICI) in Merkel cell carcinoma (MCC) or melanoma have proven efficacy.

Conference: 18th Annual ENETS Concerence (2021)

Presenting Author: Prasad V

Authors: Aicher A, Sindrilaru A, Beer A, Prasad V,

Keywords: PRRT, SILD, ICI, Merkel cell carcinoma, melanoma, tumor microenvironment remodelling,