ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

86%, 50% and 33%, %the LRFS rate was 86%, 70%, and 53%, the RRFS rate was 86%, 65%, and 49%, and the DMFS rate was 93%, 61%, and 46%, respectively. Mean OS was 21.2 months (standard error [SE]:2.2, 95% confidence interval [CI]: 17.7- 25.7) and mean PFS was 16.2 months (SE: 2.4, 95% CI: 11.4-20.9). The abscopal effect was observed in two patients who both had nasopharyngeal cancer. Acute grade 1 SBRT-related dermatitis was observed in only one patient and no other acute side effects were observed. A stent was placed in the carotid artery in two patients prior to re-irradiation due to the late SBRT-related carotid blowout syndrome (CBOS) risk. In one patient CBOS could be prevented but the other patient succumbed to CBOS. Other late SBRT-related side effects were observed in three patients (dysphagia, pituitary insufficiency, skull base osteomyelitis). A total of five patients developed ICI-related toxicity (recall dermatitis in one patient and hypothyroidism in four patients). Conclusion By using ICI and SBRT concurrently, we have achieved excellent OS and PFS and also achieved satisfactory outcomes in HN- SCC re-irradiation which is one of the most challenging areas of RT.

PO-0142 Efficacy of nivolumab in rmHNSCC. A national prospective DAHANCA cohort study

S. Søby 1 , A. Gothelf 2 , N. Gyldenkerne 3 , J. Bentzen 4 , K. Nowicka-Matus 5 , T. Tramm 6 , J.G. Eriksen 1

1 Aarhus University Hospital, Dept. of Experimental Clinical Oncology, Aarhus, Denmark; 2 Copenhagen University Hospital, Dept. of Oncology, Copenhagen, Denmark; 3 Odense University Hospital, Dept. Oncology, Odense, Denmark; 4 Herlev Hospital, Dept. Oncology, Cophenhagen, Denmark; 5 Aalborg University Hospital, Dept. Oncology, Aalborg, Denmark; 6 Aarhus University Hospital, Dept. of Pathology, Aarhus, Denmark Purpose or Objective PD-1 inhibitors are well established in the treatment of recurrent or metastatic head and neck squamous cell carcinoma (rmHNSCC). Aim of the present study was to investigate real-life phase IV efficacy of the PD-1 inhibitor nivolumab among an unselected and unbiased national cohort of rmHNSCC to determine its actual benefit. Materials and Methods Patients (pts) were eligible if they had histologically confirmed rmHNSCC and had received nivolumab as second line palliative treatment. Patient, tumor and treatment-related data were collected prospectively from patient files at the five head and neck cancer centers and from the DAHANCA-database. iRECIST was used for treatment evaluation. Descriptive statistics were used to describe patient, tumor and treatment. Endpoints were response rate (RR), overall survival (OS) and progression-free survival (PFS), calculated from start of treatment to date of event or censoring. Survival was estimated by the KM-method. Analyses were two-sided and p<0.05 were considered significant. Results In total 146 pts were identified 2017-2020. 103 (71%) were male and 43 (29 %) female with a median age of 62 years [range 36-86]. 104 (71%) had metastatic disease while 42 (29%) were of the locally advanced type. The median number of treatment cycles administered was 5 [range 1-54]. RR was 14%, median OS was 10.5 months (mo) [95% CI: 8.7-12.2] and the PFS was 3.4 mo [95% CI: 2.8-4.4]. Comparing pts in terms of PD-L1 expression (<20 % vs. ≥ 20 %) showed no difference in terms of OS. However, for PFS a PD- L1 expression ≥ 20 was associated with a better treatment response (p=0.01 HR=0.63 [95% CI: 0.44-0.90]). Disseminated vs. locally advanced disease did not affect outcome (p=0.7). OS was correlated to poor WHO PS (p<0.0001, HR=3.0 [95% CI: 2.0-4.3]). Median OS was 21.1 mo and median PFS was not reached within PS = 0. With PS = 1 median OS and PFS were 10.2 and 5.2 mo respectively and 4.8 and 2.1 mo for pts with PS ≥ 2. Elderly pts ( ≥ 70 years) had similar benefit as the younger pts (p=0.07), and no difference was found between genders (p=0.4). These data were also reflected using PFS as endpoint. OS and PFS were not significantly correlated to comorbidity. (p=0.1 resp.) Influence of steroids was tested using OS as endpoint by comparing pts who had received concomitant steroids for ≥ 50 % of the duration of their nivolumab treatment time to pts who had received it for <50 % (p=0.004 HR=2.7 [95%CI: 1.3-5.3]). The same pattern was seen for PFS. In a multivariate analysis, especially PS >0 and concomitant steroids were associated with a significantly increased risk of progression while a PD-L1 expression ≥ 20 % was significantly associated with a lower risk hereof. Conclusion This national study showed acceptable efficacy in an unselected cohort with one-fourth of pts surviving more than one year. However, around one-fourth has a rather rapid recurrence. Although a non-toxic treatment, response seems to be affected by poor performance and the need for steroid treatment during PD-1 therapy.

PO-0143 Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios in head and neck tumours

Z. Szilasi 1 , V. Jósa 2 , Z. Zrubka 3 , F. Helfferich 1 , Z. Baranyai 4

1 Hungarian Defence Forces Health Centre, ORL-HNS, Budapest, Hungary; 2 Jahn Ferenc Hospital, ORL-HNS, Budapest, Hungary; 3 Corvinus University , Health Economics, Budapest, Hungary; 4 Semmelweis University, Surgery, Budapest, Hungary