Real world data: Survival outcomes of patients with poor prognosis metastatic germ cell tumours (GCT) within a large tertiary UK centre.

e17021 Background: Patients categorised as having poor prognosis GCT, as per the International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification, have a reported 5 year survival of 48% (42-54%). The management of these patients varies between institution and is dictated by site of disease and individual patient factors. Their care remains an area of unmet need. We present our experience. Methods: Retrospective electronic records-based analysis was performed for poor prognosis GCT patients managed within the West Midlands, UK, covering a population of 1.88 million people between1999 to 2025. Collected data included; patient demographics, site of primary, histological subgroup and oncological treatments undertaken. Overall survival was calculated by Kaplan Meier analysis using GraphPad. Results: A total of 104 patients were included with a median age of 30 and age range of 16-70. 24 patients didn’t have tissue to identify histology but radiologically and biochemically were confirmed as poor prognosis germ cell tumours. 80 patients were identified as non-seminomatous germ cell tumours. The majority had a testicular primary (66%, 69 patients), with 16% (17) with mediastinal and 10% (10) with retroperitoneal primaries. The remainder of the cohort had documented primaries including: pineal (3) and sacrococcygyeal (2), liver (1) and adrenal (1), axillary (1) and 1 patient with metastases to the brain. 99% of patients received cisplatin- etoposide based first line chemotherapy, 1 patient died before the commencement of treatment. Following first line treatment, 49 patients relapsed, with the majority (n=40) receiving 2nd line TIP (Paclitaxel, Ifosfamide and Cisplatin). 2 patients received POMB/ACE (Cisplatin, Vincristine, Methotrexate, Bleomycin, Actinomycin D, Cyclophosphamide and Etoposide) and 1 patient received TICE (Paclitaxel, Ifosfamide followed by high dose Carboplatin and Etoposide). 1 patient received Oxaliplatin, Gemcitabine and 1 patient passed away before treatment. 2 patients received radiotherapy to local disease and 2 underwent surgery for recurrence. 16 patients received 3rd line treatment. 28 patients (27%) underwent Retroperitoneal Lymph Node Dissection (RPLND), with 11 patients underwent this for relapse. Progression free survival (PFS) ranged from 3 to 60 months. OS ranged from 1 month to 299 months (25 years). 45% of patients within this cohort survived over 5 years (95% CI = 44.385 - 45.615%). Patients with mediastinal primaries had an OS of 41% over 5 years. Conclusions: In comparison to the IGCCCG prognostic staging our cohort study showed a comparable OS survival for 5 years (45%) to the published data (45% vs 48%) Furthermore, patients with a mediastinal primary were evidenced to have a similar prognosis to patients with a testicular primary.