ESTRO 2022 - Abstract Book

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Abstract book

ESTRO 2022

From January 2018 to May 2021, 105 patients, including 43 women and 62 men, were qualified and treated. Sixty-seven patients were older than 70 years, the remainder had numerous comorbidities. The clinical advancement stage II was found in 25 patients, stage III in 33 patients, and in the remaining 47 patients - stage IV. Two fractionation schedules were used. Both consisted of two courses with a three-week break. In the first one SIB technique was used – patients received 45Gy at 4,5Gy per fraction to tumor volume and 40Gy at 4Gy per fraction to elective volume. The second was used in more advanced cases. Patients received 44Gy at 4Gy per fraction to the whole volume. Patients over 70 years of age were assessed according to the G8 scale. Results The mean follow-up time was 8.2 months. Seven patients were lost from follow-up. In the group of patients assessed according to the G8 questionnaire, 82% of patients received a score equal to or lower than 14 points. CR was observed in 50.5% of patients. In the group treated according to the SIB schedule, the CR percentage was 60.6%, and for the second regimen it was 33.3%. Two patients had local recurrence. Toxicity in both groups was similar. At the end of each course, patients developed mainly G1 skin toxicity and G2 on mucous membranes according to the EORTC / RTOG scale. There was no need to postpone or abandon the second course in any of the patients. Conclusion Both regimens show promising efficacy with good tolerance and could represent an alternative to palliative strategies in elderly and frail patients. C.L. deantoni 1 , A. Chiara 1 , A. Mirabile 2 , S. Broggi 3 , C. Fiorino 3 , A. Fodor 1 , M. Pasetti 1 , R. Tummineri 1 , F. Zerbetto 1 , S. Baroni 1 , A. Sanchez Galvan 1 , V. Gregorc 2 , I. Dell'Oca 1 , N.G. Di Muzio 4 1 IRCCS San Raffaele Scientific Institute, Radiation Oncology, Milano, Italy; 2 IRCCS San Raffaele Scientific Institute, Department Unit of Oncology, Medical Oncology Department, Milano, Italy; 3 IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy; 4 Vita-Salute San Raffaele University, Faculty of Medicine and Surgery, Milano, Italy Purpose or Objective Sarcopenia (SP), defined as loss of muscle mass and functions, recently emerged as an independent prognostic factor in oncological patients (pts), connected with poor survival and sometimes with a higher treatment toxicity profile. This study aims to determine the possible impact of SP on survival and acute toxicity in our oropharyngeal pts. Materials and Methods 76 pts with locally advanced oropharyngeal squamous cell carcinoma, stage III-IVC, were treated in our Center with Helical TomoTherapy (HT) between 2005 and 2021. HT was delivered with a Simultaneous Integrated Boost (SIB) technique: 54 Gy (1.8 Gy/day) to the clinically negative neck region and 66 Gy (2.2 Gy/day) or 69 Gy (2.3 Gy/day) to the tumor and positive nodal regions based on 18FDG CT/PET imaging. All pts received concomitant platinum-based CT (at least 200 mg/m2). SP is generally determined on single-slice CT measurement of the cross sectional muscle area (CSA) at the level of the third lumbar vertebra (L3). Swartz et al (2016) proposed and validated an algorithm that correlated CSA at L3 with CSA at C3, easier to obtain in head and neck pts, and then CSA at C3 with lumbar skeletal muscle index (SMI). Twenty pts (26%) presented SP at the beginning of treatment, according to Prado (2008) that defined SP if SMI was <55.4 cm2/m2 in males and < 39 cm2/m2 in females. Results All pts concluded the treatment. The acute toxicity profile was analyzed as “less than” versus “more or equal to” grade 3 CTCAE 4.0. 13 pts (65%) in SP group and 22 pts (39%) in non-SP group presented a toxicity more or equal to grade 3, but this difference was not statistically significant (p-value 0.25). Overall survival was analyzed in 65 pts (47 NS and 18 S), excluding pts who finished CT RT less than 6 months ago (median follow up 41, range 3.4-126.1). Overall survival was significantly different in non-SP versus SP group (fig 1, p value 0.035). The same difference was notable in N0-N2a pts, suggesting an important role of SP also in pts with a lower nodal burden and theoretically better prognosis. PO-1100 Impact of sarcopenia in oropharyngeal cancer patients treated with radical chemo-radiotherapy

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