ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

distant failure was not reached, with 5-year Kaplan-Meier estimate of distant control of 61.1%. Median time to any recurrence was not reached, with 5-year Kaplan-Meier estimate of recurrence-free survival of 53.9%. A significantly increased proportion of patients receiving concurrent chemotherapy were node-positive at 94.1% vs. 38.2% in the adjuvant radiation therapy alone cohort (p<0.01). In the entire cohort, there was no significant difference in overall survival (p=0.33), locoregional control (p=0.63), or distant control (p=0.31) noted with the addition of chemotherapy. On subgroup analysis only including the 29 node-positive patients, there was no significant difference in overall survival (p=0.97), locoregional control (p=0.83), or distant control (p=0.99) with the addition of chemotherapy. Conclusion Within our retrospective cohort, we were unable to demonstrate a significant improvement in any examined endpoint with the addition of chemotherapy in the adjuvant treatment of intermediate to high-grade salivary gland malignancies with high-risk features, potentially secondary to sample size limitations. Prospective data is needed in this setting to determine whether patients may potentially benefit from addition of concurrent systemic treatment, particularly given high rates of distant failure on long-term follow-up. L. Lorini 1 , V. Tovazzi 1 , S. Battocchio 2 , M. Zannoni 3 , S. Cingarlini 4 , S. Nicolini 1 , G. Piccinelli 1 , G. Paolino 3 , M. Tomasoni 5 , M. Ravanelli 6 , L. Ardighieri 2 , A. Bozzola 2 , A. Grammatica 5 , A. Paderno 5 , M. Zamparini 1 , M. Buglione 7 , R. Nocini 8 , F. Facchetti 2 , S.M. Magrini 7 , R. Maroldi 9 , C. Piazza 5 , A. Scarpa 10 , P. Bossi 1 1 ASST Spedali Civili - University of Brescia, Medical Oncology Unit, Brescia, Italy; 2 ASST Spedali Civili - University of Brescia, Pathology Unit, Brescia, Italy; 3 University and Hospital Trust of Verona, Diagnostics and Public Health, Section of Pathology, Verona, Italy; 4 University and Hospital Trust of Verona, Medical Oncology Unit, Verona, Italy; 5 ASST Spedali Civili - University of Brescia, Unit of Otorhinolaryngology - Head and Neck Surgery, Brescia, Italy; 6 ASST Spedali Civili - University of Brescia, Radiology Unit, Brescia, Italy; 7 ASST Spedali Civili - University of Brescia, Radiation Oncology Unit, Brescia, Italy; 8 University and Hospital Trust of Verona, Otorhinolaringology and Head & Neck Surgery, Verona, Italy; 9 ASST Spedali Civili - University of Brescia, Radiology Unit, Brescia, Italy; 10 University and Hospital Trust of Verona, Diagnostics and Public Health, Section of Pathology , Verona, Italy Purpose or Objective From 25 to 50% of radically resected Merkel Cell Carcinoma (MCC) will develop local or distant recurrence. Upon relapse, the prognosis dramatically worsens with a 5 year OS decrease from 50% to 13%. Very few data exist about prognostic factors influencing the risk of recurrence and survival in MCCs of the Head and Neck (HN) region. The aim of this study is to evaluate the association between clinical/histological characteristics of MCCs pts and the risk of disease recurrence and survival. Materials and Methods We retrospectively evaluated a series of 57 MCCs pts treated with curative surgery at ASST Spedali Civili of Brescia and Azienda Ospedaliera Universitaria of Verona from 2000 to 2020, and data from 21 pts affected by HN MCCs were retrieved. The following clinical and histological characteristics were analyzed and associated with relapse-free survival (RFS) and overall survival (OS): gender, age, comorbidity (analyzed with Charlson Comorbidity Index), type of primary treatment, surgical margins, Breslow index, perineural or lymphovascular infiltration, TNM stage, presence of T-cell inflammatory infiltrate (TILs, CD3+, CD4+, and CD8+), MCC polyomavirus positivity, and Ki67 and PDL1 expression (CPS) Results In our series, pts were mainly female (66%), with a median age at diagnosis of 78 years (53-99). All pts underwent surgical resection of primary tumor and 14% received also adjuvant radiotherapy. During a median follow-up of 12 months (5- 135), 54% had a locoregional or distant recurrence. Median RFS and median OS were 20 months (12-44) and 16 months (7-24) respectively. In univariate analysis, only female gender (HR 0.128; 0.03-0.541; p 0.005) was associated with a reduction of risk of local or distant relapse of disease. Virus-positive MCCs (HR 0.122; 0.026-0.576), a moderate or high tumoral infiltration of CD3+ T cells (HR 0.171; 0.036-0.0814), and a moderate or high tumoral infiltration of CD8+ T cells (HR 0.215; 0.047-0.993; p 0.049), as well as pts with a RFS > 8 months (HR 0.255; 0.067-0.966; p 0.044) were associated with an improved OS. Conclusion In this series of HN MCCs, only female gender was associated with a lower risk of recurrence. Higher tumoral immune cells infiltration, virus-positive MMCs, and pts with an RFS > 8 months were associated with improvement of OS. Given the lack of clinical/pathological prognostic data, we advocate that molecular characterization of MCCs might contribute to better stratify the risk of recurrence and prognosis of HN MCCs, thus defining a population that could benefit from preventive strategies within clinical trials. PO-0176 Clinical and histological prognostic factors in a series of Head and Neck Merkel Cell Carcinomas

PO-0177 The role of ultrasonography in the diagnosis and treatment of the head and neck NMSC.

T. Tamas 1 , C. Dinu 1 , E. Botan 2 , S. Stoia 1 , L. Manuela 3 , A. Tamas 4 , S. Bran 5 , M. Baciut 5

1 University of Medicine and Pharmacy "Iuliu Hatieganu" Cluj Napoca, Romania, Department of Maxillofacial Surgery and Implantology, Cluj Napoca, Romania; 2 University of Medicine and Pharmacy "Iuliu Hatieganu" Cluj Napoca, Romania, Department of Pathology, Cluj Napoca, Romania; 3 University of Medicine and Pharmacy "Iuliu Hatieganu" Cluj Napoca, Romania, Department of Radiology, Cluj Napoca, Romania; 4 University of Medicine and Pharmacy "Iuliu Hatieganu" Cluj