ESTRO 2022 - Abstract Book

S1242

Abstract book

ESTRO 2022

Results Twenty-two patients (17 male and 5 female) with histological diagnosis of neoplastic and systemic disease were enrolled. The median age was 75 years (range 42-91); all patients had contrast-enhanced CT, 18F-PET/CT and in selected cases contrast-enhanced MRI. The first therapy’s phase provided to deliver high radiation doses within bulky tumour using “balls of dose”, called VERTEX, positioned between hypoxic and normoxic tissue following a non-geometric model. The median total dose delivered on VERTEX was 15Gy (range 10-27Gy) in 1-5 fractions. In the second treatment phase, a median total dose of 30Gy (range 18 – 40,05Gy) was delivered on GTV ± Clinical Target Volume (CTV). With a median follow up of seven months (range 1-13 months) we recorded an 89% of clinical response (figure 1; 2). Particularly, 23% of the patients showed a complete response (CR) and in 63% of patients, a partial response (PR) has been observed. Stable disease (SD) and progression disease (PD) were 9% and 4.5% respectively. The toxicities records were poor: radiodermatitis G1 have been observed in the 36% of the patients, while no grade 3 toxicities were recorded.

Conclusion The LATTICE_01 approach is feasible and well tolerated with encouraging results in terms of toxicities and overall response rate. These preliminary results seem to indicate that this kind of therapy could emerge as a therapeutic option in this setting of patients.

PO-1463 SBRT for over 80years oligometastatic patients: report of feasibility and clinical outcomes

F. Cuccia 1 , R. Mazzola 1 , E. Pastorello 1 , V. Figlia 1 , N. Giaj-Levra 1 , L. Nicosia 1 , F. Ricchetti 1 , M. Rigo 1 , C. Vitale 1 , G. Attinà 1 , R. Ruggieri 1 , F. Alongi 1

1 IRCCS Sacro Cuore Don Calabria, Advanced Radiation Oncology Department, Negrar di Valpolicella, Italy

Purpose or Objective Purpose: With a constantly increasing life expectancy, the issue of treating oncological older patients rises, representing a therapeutical challenge for the scientific community. Several literature studies support SBRT in the treatment of the oligometastatic patient as a potentially curable therapeutic option. However, data on older patients are sparse. Materials and Methods Methods: From December 2013 to October 2020 a cohort of 61 oligometastatic patients over the age of 80 years received SBRT, which was proposed for subjects with a minimum Karnofsky Performance Status ≥ 70, a life expectancy of at least 6 months, and up to five oligometastatic lesions. Radiotherapy was delivered in 3-10 fractions with VMAT-IGRT technique. Toxicity was retrospectively collected according to CTCAE v4.0. Univariate and multivariate analysis were performed for assessing any potential predictive factor for clinical outcomes. Results Results: A total of 90 oligometastases were treated in 61 patients with median age 82 years (range, 80-90). The most frequent histology was colorectal cancer (27% of cases). With a median follow-up of 20 months (2-63), our Local control rates at 1- and 2-years were 98.8% and 88.2%. Colorectal histology was found to be associated with worse LC rates (p = 0.014) at univariate analysis. Progression-free survival rates at 1- and 2-years were 48.6% and 30.5%. At univariate analysis, oligorecurrent lesions and single oligometastases were associated with better PFS rates (respectively, p = 0.04 and p = 0.011). 1- and 2-years overall survival rates were 75% and 60.5%, with polymetastatic spread being predictive of lower survival outcomes at multivariate analysis (p = 0.012). All treatments were well tolerated with no interruptions and no G2 or higher adverse events recorded.