ESTRO 2022 - Abstract Book

S909

Abstract book

ESTRO 2022

located in: oral cavity 31.3%, larynx 25.4%, oropharynx 23.9%, parotid 7.5%, ear canal 5.9%, hypopharynx 3%, nasopharynx 3%. Median follow-up was 8 months (range: 1-44 months). The median values of pre-treatment NLR and PLR were 1.97 (range: 0.07-16.00) and 121.25 (range: 50-285), respectively. A statistically significant correlation between OS and a PLR value > of PLR median ( p-value=0.053 ) was found (Table 1). There were no statistically significant correlations between NLR ratio and clinical outcomes (OS, LR, DM). Both NLR and PLR were not associated with acute toxicity, neither acute cutaneous nor total toxicity (Table 2).

Conclusion The prognostic significance of NLR and PLR have been explored in several cancers. In our study a higher pre-treatment PLR in HNSCC patients resulted predictive of worse OS. The study is still ongoing in order to validate a larger number of patients and to investigate further readily available biomarker helpful to improve pre-treatment prognostication and to define predictive models of risk-stratification.

PO-1074 Prognostic factors analysis of carcinoma ex pleomorphic adenoma of major salivary glands

Y.H. Chang 1 , C. Kuo 2 , J. Lin 1

1 Changhua christian hospital, Department of radiation oncology, Changhua, Taiwan; 2 National cheng kung university hospital, Department of oncology, Tainan, Taiwan Purpose or Objective Carcinoma ex pleomorphic adenoma (CXPA) is an uncommon malignant tumor with aggressive behavior but the treatment outcome and prognostic factors are rarely reported. Materials and Methods From April 2008 to January 2021, 22 patients with pathologically proven CXPA were collected. The treatment modality contained surgery alone (2), surgery plus adjuvant radiotherapy (13) or chemoradiotherapy (5), and definitive chemoradiotherapy (2). We analyze the associations between clinical characteristics and treatment outcomes. Results After a median follow-up of 46.5 months (range 13-114), we observed 8 relapses (distant metastasis predominantly) and 5 deaths (all due to uncontrolled tumor). The 5-year overall survival (OS), relapse-free survival (RFS), locoregional-free survival (LRFS) and distant metastasis-free survival (DMFS) were 71.7%, 64.2%, 76.3% and 64.6%, respectively. Kaplan-Meier survival curve analysis revealed only tumor origin was a significant factor for OS. The 5-year rates of OS for the tumor arising from parotid gland and submandibular gland were 88.9% and 26.7%, respectively (P=0.011). Univariate analysis identified some potential biomarkers in predicting worse survivals- OS, submandibular vs. parotid origin (P=0.029); RFS, clinical regional lymph nodes positive vs. negative (P=0.061); LRFS, age>50 vs. ≦ 50 (P=0.083) and clinical regional lymph nodes positive vs. negative (P=0.069); DMFS, submandibular vs. parotid origin (P=0.095). When we focused on 20 patients who received surgery, invasiveness (invasive subgroup vs. minimal invasive/non-invasive subgroups) and pathological T- stage (T4 vs. T1-3) were two important prognostic factors on survivals. Conclusion Patients with tumor arising from parotid glands (versus submandibular glands) had significant better OS. Patients with clinical regional lymph node metastasis or older age had relatively worse survivals. Invasiveness and pathological T-stage affect various survivals for patients who received surgery-based treatment.