ESTRO 2024 - Abstract Book

S2263

Clinical - Upper GI

ESTRO 2024

CLD (59/63, 94%). Child-Pugh A was 49/63 (78%), with all others Child-Pugh B. Median MELD score was 9 (IQR 7 – 13). 32 patients had received prior HCC treatment (median 1 therapy, IQR 0 – 2, max 8). In 22/32 (69%) of patients, the SBRT was to treat an HCC lesion that was the target of their most recent prior therapy (14/22 TACE, 7/22 ablation, 1/22 systemic therapy). Two patients had previously been transplanted, so local therapies delivered before this were disregarded. Median largest tumour treated was 23mm (IQR 18 – 31mm). More than one tumour target was treated in 10/63 (16%).

Most patients (60/63, 95%) received their planned dose (3 patients having final fraction omitted, as GI tract position uncertainties prevented safe delivery). Delivered doses in 5 fractions were 50 Gy (50/63), 45 Gy (5/63), 40 Gy (4/63), 35 Gy (1/63). Other regimens were: 45 Gy in 3 fractions (1/63), 40 Gy in 4 fractions (2/63), 36 Gy in 4 fractions (1/63). Median mean liver dose was 7.7 Gy (IQR 6.0 – 11.2 Gy, Max 15.1 Gy). Max dose to the most spared 700cc of liver was median 3.3 Gy (IQR 0.82 – 12.2 Gy). 5 patients (1 with progressive disease) were subsequently transplanted, one dying due to ischaemic cholangiopathy driven graft failure. Of 24 other patients with imaging confirmed progressive disease, treatment at first progression was systemic therapy in 8, local therapy in 9 and no further treatment in 7. Immunotherapy was used in 3/8 patients receiving systemic therapy at first progression and 2/3 patients receiving systemic therapy at second progression. Figure 1 shows Kaplan-Meier for OS; median overall survival was 25 months; 1 year OS was 75% (95% CI: 62 – 84%); 2 year OS was 54% (95% CI 39 – 67%).