ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

Variation of dose on the horizontal axis among five patients (PSQA/Plan Dose) was between 0.1% to 8.1% , and β factors were between 1.5 to 1.7 approximately. For the radial dose factor, the maximum difference of the TPS compared to the Monte Carlo simulation data was about 3.7%, and compared to the dosimetric film was about 2.4%. For angular dose factors, these values were 5.1% and 2.5%. According to TPS and experimental dosimetry, dose calculation was slightly different in this project, with 7-8% for the bone and 5-6% for the skin tissue. Conclusion The literature study shows that the algorithms used in the TPS dose calculations don’t have the ability to calculating dose variations in heterogeneous regions as much as the Monte Carlo methods.

PO-0095 The role of salvage in the management of patients with sinonasal malignancies.

U. Kacorzyk 1 , T. Rutkowski 2

1 National Research Institute of Oncology, I Radiation and Clinical Oncology Department, Gliwice, Poland; 2 National Research Institute of Oncology, I Radiation and Clinical Oncology Department, Gliwice, Poland Purpose or Objective Malignant tumors of the nose and the paranasal sinuses (sinonasal malignancies, SNM) are often diagnosed in their advanced stages. Local recurrence remains the main reason treatment fails and is diagnosed in about 50% of patients with SNM. Due to this, the question arises as to how effective the salvage procedure offered to these patients actually is. Materials and Methods A review of retrospective clinical data of 146 consecutive patients with either nasal cavity or paranasal sinuses tumors treated radically between 2000 and 2016 in the National Cancer Research Institute, Gliwice branch, was performed. Squamous cell carcinoma was found in 79 (54%) cases. Maxilla was the primary tumor localization in 85 (58%) cases. In most cases, the tumor was locally advanced 100 (67.5%). Surgery was the primary treatment approach in 117 (80%) patients and followed induction CHT in 8 (6%) patients. The ratio and effects of salvage were analyzed. Probabilities of overall survival (OS), local control (LC), nodal control (NC), and locoregional control (LRC) were estimated from the end of RT using the Kaplan-Meier method and were compared by the log-rank test. Univariate analysis was used to evaluate the impact of clinical and treatment parameters on primary and salvage treatment outcomes. Results The 5-year and 10-year OS amounted to 62% and 45%. In 60 (41%) patients, treatment failure was observed. Locoregional failure was significantly higher for patients with primary symptoms lasting shorter than 5 months (p=0.04). A significantly higher ratio of locoregional failure was also found for patients without surgery (p=0.04). For patients eligible for salvage, median time to failure was 10 months and for those who were not eligible – 2 months (p=0.005). The 5- and 10- year OS rates for patients with the median time to failure <= 7 months and >7 months were 25%, 17% and 63%, 44%, respectively (p=0.002). Salvage was performed in 36 (60%) patients. The 5- and 10- year OS rates for patients with disease failure who underwent salvage and who did not have such treatment, were 60%, 44% and 11%, 11% (p=0.0008), respectively. For patients with successful salvage, the 5- and 10- year OS was significantly higher compared to those with failed salvage: 90% v 25% and 72% v 0% respectively (p=0.0003) and did not differ significantly when compared to the OS of primarily cured patients (p=0,3). Surgery was the most frequent type of salvage both as a single approach (53%) and as a component of combined treatment (84%). Conclusion Patients after radical treatment due to SNM should remain under oncological surveillance since salvage therapy is possible in more than 50% of those with failure and can improve their overall survival. Surgery is the most effective salvage option. Moreover, effective salvage can compensate for the failure and give the same ultimate OS as in primarily cured patients.

PO-0096 ICIs in high risk oral potentially malignant lesions (IMPEDE study): an interim analysis on safety

A. Alberti 1,1

1 University of Brescia, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, Brescia, Italy Purpose or Objective Oral Potentially Malignant Disease (OPMD) represent the most common oral precancerous condition, with a risk of malignant transformation varying according to different studies. The most effective biomarker in predicting malignant transformation risk is loss of heterozygosity (LOH). Patients (pts) carrying OPMD with LOH at 3p14 and/or 9p21 plus LOH at another locus have an expected 3-year risk of developing oral cancer of 35%. This chromosomal profile is found in about 28% of OPMD. IMPEDE is a p hase II, open-label, single-arm trial designed to evaluate the efficacy of avelumab in reverting cancer transformation risk in OPMD with LOH. In this analysis, we report the first safety results. Materials and Methods During the screening period, pts undergo OPMD biopsy. If pathological diagnosis of dysplasia is confirmed, LOH valuation is performed and in case of positivity of this biomarker, subjects receive a short course of immunotherapy with avelumab 800