ESTRO 2024 - Abstract Book

S1062

Clinical - Gynaecology

ESTRO 2024

was 3 (range 0 – 11 treatment lines) reported in 7 studies. Only 3 studies reported BRCA status, one of which a case report where the patient was BRCA negative, one retrospective study where BRCA status was known in 40.4% of the population (of which 18.3 % were BRCA 1/2 positive), while in another one 14% of patients had a BRCA 1 mutation. In total, 809 lesions were treated with SBRT with a median dose of 40 Gy (range 5 - 75 Gy). In the case reports, each patient was treated for 1 to 3 lesions simultaneously, while in three studies almost half of the patients had only one lesion treated (range 48.5 – 55.9%). Following a median follow up of 22 months (range 2.2 - 108 months) the median reported PFS was 12 months (range 5.6 – 108 months). Despite the limits inherent to heterogeneity over frequency and type of imaging for assessment of clinical response, ORR ranged from 74 to 100%. Likewise, median time to systemic treatment was 9.45 months (range 2.1 – 49.3 months) for the two studies who reported on this while the median 1-year OS in 6 studies was 100% (range 80 – 100%). SBRT was associated with only mild acute and late toxicity, with up to G2 events reported, even in patients having up to 8 lesions treated in the course of the disease. In total, there were one G3 and one G5 events of gastrointestinal acute and late toxicity respectively (duodenal ulcer). Both patients had a single lesion treated. The acute G3 event developed in the setting of a periportal lymph node target and there was no bevacizumab administered before or after SBRT. The late G5 event was a radiation induced related toxicity of a single lesion in porta hepatis treated at 18 Gy in 3 fractions a month after another SBRT in porta hepatis of 21 Gy in 3 fractions. It is not reported if there was a concomitant chemotherapy.

Conclusion:

The evidence on the efficacy and safety of SBRT in recurrent oligometastatic ovarian disease is limited but encouraging. More studies reporting on consistent data is essential to better and fully assess the outcomes of this treatment.

Keywords: SBRT, ovarian, oligometastatic

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Digital Poster

 Patterns of recurrence and prognostic factors in early-stage endometrial cancer

Ji Soo Sung 1,2 , Hak Jae Kim 1,2 , Hyun-Cheol Kang 1,2 , Kyung Su Kim 1,2 , Keun Yong Eom 3,2

1 Seoul National University Hospital, Radiation Oncology, Seoul, Korea, Republic of. 2 Seoul National University College of Medicine, Radiation Oncology, Seoul, Korea, Republic of. 3 Seoul National University Bundang Hospital, Radiation Oncology, Seongnam-si, Gyeonggi-do, Korea, Republic of

Purpose/Objective:

Early-stage endometrial cancers generally have a favorable prognosis, but a subset of patients experiences recurrences. Existing risk stratification systems have limited predictive accuracy and clinical utility. Future trials that combine molecular and clinical factors are expected to require a substantial amount of time to produce results. Consequently, we conducted an analysis of recurrence patterns, examined the recurrence-free rate based on the 2016 ESMO-ESGO-ESTRO risk classes, and identified potential prognostic factors for recurrence.