Abstract 2022-RA-1148-ESGO Table 1 Responses to 1st line treatment Sig3+ Sig3- p-value N % N % All patients 56 60 Primary therapy outcome 0.025 Complete response 38 69.1 28 47.5 Partial response 15 27.3 19 32.2 Stable disease 3 5.1 Progressive disease 2 3.6 9 15.3 No data 1 1 Platinum-free interval <0.001 <6 months 11 20.4 30 50.8 6–12 months 9 16.7 17 28.8 >12 months 34 16.7 17 28.8 Conclusion Mutational signature 3 test can identify reliable cancers with HRD. Sig3 status predicts treatment outcome and overall survival. Further studies are needed to evaluate clinical validity of Sig3-based assay for predicting PARPi benefit. 2022-RA-1149-ESGO OXALIPLATIN-BASED TREATMENTS ARE CURRENTLY A VALID THERAPEUTIC OPTION IN HEAVILY PRETREATED OVARIAN CANCER PATIENTSWITH HYPERSENSITIVITY REACTIONS (HRS) TO CARBOPLATIN IN THE ANTIANGIOGENICS AND PARPI ERA 1 Jennifer Olalla Inoa, 2 Laura Sanchez Escudero, 1 Aranzazu Manzano, 1 Gloria Marquina, 3 Pluvio Coronado, 3 Francisco Javier Garcia-santos, 3 Monica Bellon, 4 Leticia Sanchez Morillas, 4 Montserrat Fernandez Rivas, 5 Ramiro Mendez Fernandez, 6 Pedro Perez Segura, 6 Antonio Casado. 1 Department of Medical Oncology, Hospital Clínico San CArlos, Madrid, Spain; 2 Department of Medical Oncology, Hospital Juan Ramon Jimenez, Huelva, Spain; 3 Gynaecologic Oncology Unit, Hospital clinico san carlos, Madrid, Spain; 4 Department of Alergology, Hospital Clínico San Carlos, Madrid, Spain; 5 Department of Radiology, Hospital clinico san carlos, Madrid, Spain; 6 medical oncology, Hospital Clínico San Carlos, Madrid, Spain 10.1136/ijgc-2022-ESGO.652 Introduction/Background Oxaliplatin, in the era prior to anti- angiogenics and PARPi therapies, demonstrated activity in patients (pts) with ovarian cancer (OC) in phase I, II and III studies. Oxaliplatin may play a role in pts with hypersensitiv- ity reactions (HRs) to carboplatin. Methodology Single-institution retrospective experience (2004– 2022) in terms of efficacy and safety with oxaliplatin in recur- rent OC, especially in pts with HRs to carboplatin.SPSS ver- sion 22.0 was used for statistical analyses Results 68 pts were treated with oxaliplatin (monotherapy, 25%, in combination 75%, mostly with gemcitabine (56.4%) or paclitaxel (15,1%). Pts and disease characteristics are shown in Table 1. Median progression free survival (mPFS) and over- all survival (mOS) were 3 and 13 months (m), respectively. There was no difference between platinum-resistant and plati- num-sensitive in terms of PFS, but there was a benefit in mOS in platinum-sensitive disease (13 vs 6 m). Pts who attained controlled disease with oxaliplatin showed a mPFS of 6 months and mOS of 15 months. 45.9% of patients had experienced prior HRs to carboplatin; 67% of them did not require desensitization to oxaliplatin. However, 17.8% of the patients suffered HRs to oxaliplatin. PARPi before oxaliplatin was used in 5 pts. Of them, two stable diseases were achieved with no objective responses. Pts with clinical benefit to oxali- platin and who had received prior bevacizumab had a 64% lower risk of progression (HR 0.36 IC 95% 0.169–0.800,p 0.012), and patients with no benefit from oxaliplatin had a better outcome with the previous use of bevacizumab (HR 0.20, IC 95% 0.064 – 0.679,p=0.009). Grade 3/4 toxicity was observed in 36.8%, mainly hematological and gastrointes- tinal toxicity. Abstract 2022-RA-1149-ESGO Table 1 Conclusion Oxaliplatin improves PFS and OS in pts with OC recurrent setting, in particular in those pts not candidates to receive carboplatin-based regimens mainly due to HRs. Oxali- platin is currently a valid treatment. 2022-RA-1156-ESGO VALIDATION OF PERITONEAL CANCER INDEX (PCI) SCORE AS A NON-INVASIVE TOOL FOR SURGICAL RESECTABILITY IN ADVANCED OVARIAN CANCER PATIENTS IN A TERTIARY CARE CENTER OF PAKISTAN 1 Humaira Aziz, 2 Uzma Chishti, 3 Imrana Masroor, 2 Aliya B Aziz. 1 Obstetrics and Gynaecology, Aga Khan University Hospital Karachi Pakistan, karachi, Pakistan; 2 Obstetrics and Gynaecology, Aga Khan University Hospital, Karachi, Pakistan; 3 Department of Radiology, Aga Khan University Hospital, Karachi, Pakistan 10.1136/ijgc-2022-ESGO.653 Abstracts A306 Int J Gynecol Cancer 2022;32(Suppl 2):A1–A504 on December 3, 2023 by guest. Protected by copyright. http://ijgc.bmj.com/ Int J Gynecol Cancer: first published as 10.1136/ijgc-2022-ESGO.653 on 20 October 2022. Downloaded from