Results of combined therapy with pemetrexed and carboplatin in progressive ovarian cancer.

e17598 Background: In the structure of overall oncological morbidity in Uzbekistan, ovarian cancer ranks 7th, with an incidence rate of 2.9 per 100,000 population in 2022. Among female malignancies, ovarian cancer ranks 3rd after breast cancer and cervical cancer, with an incidence of 5.8 per 100,000. Pemetrexed, a multi-enzyme inhibitor, blocks the synthesis of purine and pyrimidine nucleotides, making it effective in combating rapidly dividing tumor cells. Due to its multi-component action, pemetrexed is effective against various tumors, including mesothelioma and non-small cell lung cancer, and is considered a promising treatment option for progressive ovarian cancer. Methods: A retrospective study evaluated the efficacy of combined therapy with pemetrexed and carboplatin in 15 patients with progressive ovarian cancer. The study covered the period from April 2021 to June 2024. Pemetrexed was administered at a dose of 500 mg/m², and carboplatin was calculated based on AUC6, both administered intravenously on the first day of each 21-day cycle. The treatment included six cycles. All patients received standard premedication to minimize toxic effects, including antihistamines, corticosteroids, and vitamin B12. All patients had previously undergone standard treatment, including cytoreductive surgery and platinum-based chemotherapy. Most patients (66.7%) received the carboplatin + paclitaxel regimen, while the remaining 33.3% were treated with gemcitabine-based regimens. Upon disease recurrence, the combination of pemetrexed and carboplatin was used in the second-line treatment. Results: The immediate results of the second-line therapy showed an overall response rate of 53.3%. No complete responses were recorded, but partial responses were observed in 8 patients (53.3%). Stable disease was noted in 7 patients (46.7%), and no disease progression was observed. The median progression-free survival (PFS) was 7.2 months (95% CI: 6.1–9.4), while the median overall survival (OS) reached 18.7 months (95% CI: 11.2–21.3). Adverse effects included grade 1–2 anemia in 6 patients (40%) and grade 3 neutropenia in 2 patients (13.3%). These complications were successfully managed with symptomatic therapy and did not require treatment discontinuation. One patient experienced mild gastrointestinal toxicity, which was resolved with standard antiemetic therapy. Conclusions: Despite significant advancements in diagnosis and treatment, the prognosis for patients with progressive ovarian cancer remains poor. In this context, the search for new, effective therapeutic strategies is critically important. Combined therapy with carboplatin and pemetrexed represents a promising approach that could improve outcomes for patients with recurrent ovarian cancer who are sensitive to platinum-based therapy.