ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

Materials and Methods Ninety-nine patients who underwent SIB-IMRT radical irradiation between August 2015 and December 2018 were studied. The median age was 68 years (31-81 years), the primary site was nasopharynx/middle pharynx/hypopharynx/larynx=14/36/32/17 (clinical stage 3-4: 83%), and all patients received concurrent medical therapy (CDDP/CET=85/14). SIB-IMRT was performed for a total of 33 doses, 70 Gy/58-60 Gy in high-risk areas for primary plus metastatic lymph nodes, and 48-50 Gy in preventive areas mainly for bilateral level II-IV lymph nodes. The dose constraint was set at a mean dose of less than 20/26 Gy for the healthy parotid gland (target/acceptable) and less than 35/45 Gy for the healthy submandibular gland (target/acceptable). Results At a median follow-up of 15 months (2-45 months), there were 5 cases of residual/recurrent regional lymph nodes, all within the high-risk/intermediate-risk region (presented at the 2019 Head and Neck Cancer Conference). The percentage of patients who achieved the target/permissible dose for the healthy parotid gland was 68%/88% and 23%/58%, with a higher percentage for the healthy parotid gland. Of the 11 cases that exceeded the allowable dose for the healthy parotid gland, 5 were primary nasopharyngeal and 7 were T4 and/or bilateral N+ cases. Conclusion Using SIB-IMRT with a preventive dose of 48-50 Gy, we were able to perform treatment that met the prescribed dose constraints in many normal tissues. It is necessary to individualize the prescribed dose for each case.

PO-0085 Intraoperative Radiotherapy Safety and Efficacy in the treatment of local advanced laryngeal cancer

Y. Yang 1

1 Tianjin First Central Hospital, Department of Radiotherapy and Department of Otorhinolaryngology Head and Neck Surgery, Tianjin, China

Purpose or Objective to evaluate the dose safety and efficacy of low-energy X-ray (50KV) IORT in LAL patients.

Materials and Methods In this single-arm prospective exploratory clinical study, patients with T2N1-3 or T3-4 laryngeal carcinoma were enrolled between January 2019 to September 2020. Total laryngectomy was performed by the same surgeon. According to the patient individual conditions, after the tumor resection the patients received a boost dose of 8Gy-15 Gy applied to the tumor bed at high risk of tumor recurrence using a mobile low energy 50kV X-ray source (Intrabeam®, Carl Zeiss, Obercochin, Germany). After the followed by intraoperative radiation therapy (IORT), the patients received postoperatively an external beam radiotherapy treatment (EBRT) of 50Gy-60Gy. Acute and chronic adverse reactions and tumor recurrence in situ were monitored. The toxicity of IORT and EBRT were evaluated by “scoring system for evaluating complications of IORT” and EORTU/RTOG, respectively. Results A total of 48 subjects were included in this study, of whom 43(89.58%) were male, with mean age of 62.63±8.82 years. There were 47 patients with squamous cell carcinoma and 1 patient with adenoid cystic carcinoma. For the treatment of the study subjects, 2 (4.17%) patients received 8Gy doses of radiation, and 8 (16.67%), 22 (45.83%), 16 (33.33%) patients received 10Gy, 12Gy, 15Gy doses of radiation, respectively. Toxicological reactions and local recurrence of tumor were observed for a median follow-up time of 706 days (from 388 days to 982 days). No clear adverse events, toxicity of grade 3 or higher, was observed after the IORT not the EBRT. In addition, no local recurrence has been found so far. Conclusion In a median follow-up period of 706 days, our results suggest that total laryngectomy combined with IORT and EBRT is a safe and effective option. in the treatment of local advanced laryngeal cancer.

PO-0086 Is there a role of local treatment for oligometastatic SCCHN in the immunotherapy era?

V. Espeli 1 , F. Barucca 2 , F. Martucci 3

1 IOSI, Oncology, Bellinzona, Switzerland; 2 Ospedale Regionale di Lugano, Otolaryngology-Head and Neck Surgery, Lugano, Switzerland; 3 IOSI, Radiotherapy, Bellinzona, Switzerland Purpose or Objective Patients with oligometastatic squamous cell carcinoma of the head and neck (SCCHN) may have a better prognosis if treated aggressively but no surgical or radiotherapy treatment guidelines exist, especially in the immunotherapy era. The first randomized phase III study demonstrating a survival benefit from immunotherapy in SCCHN patients was published in 2016. The objective of this retrospective study was to report the outcome of local treatment for extra head and neck metastasis added to systemic treatment in a single Institution. Materials and Methods Data from the Oncology Institute of Southern Switzerland Registry were used and we retrospectively reviewed cases of oligometastatic SCCHN treated between January 2016 and February 2021. We analysed patients with ≤ 3 extra head and