The dissertation includes data from 247 stage III-IV ovarian cancer patients treated at the Municipal Non-Commercial Enterprise "Prykarpattia Clinical Oncology Center of Ivano-Frankivsk Regional Council" between 2017 and 2023.
A mandatory diagnostic component for all study participants included contrast-enhanced CT scans of the chest, abdominal cavity, and pelvis. CT was performed to evaluate tumor spread and calculate the Peritoneal Carcinomatosis Index (PCI), which was used to assign patients to study groups.
Assessment of Surgical PCI: Surgical peritoneal carcinomatosis index (PCI) was evaluated in groups I and II during primary cytoreductive surgery (PDS) and in groups III and IV during diagnostic laparoscopy for morphological verification. Correspondingly, surgical PCI values were higher compared to radiological PCI due to the inability of CT to fully assess the abdominal cavity. The quality of life in stage III-IV ovarian cancer patients who received 3 cycles of NACT followed by interval cytoreductive surgery did not differ from those who underwent primary cytoreductive surgery as the first treatment stage. Thus, of the 247 stage III-IV ovarian cancer patients, 51 were platinum-resistant: 16 (5.5%) had platinum-refractory recurrences, and 35 (14.2%) had platinum-resistant recurrences, most commonly originating in the abdominal cavity. The 3-year overall survival rate in group III was 41%, compared to 39% in group II and 18% in group IV. The 3-year progression-free survival rate was 21% in group II, 20% in group III, and 6% in group IV. Negative prognostic factors included PCI at the start of treatment, surgical radicality (R0, R1, R2), and tumor sensitivity to platinum-based drugs (p<0.05, odds ratio analysis). Scientific Novelty of the Results: Additional scientific data have been obtained regarding negative prognostic factors in stage III-IV ovarian cancer patients. When PCI was 11-20 points compared to 21-39 points, the 3-year overall survival rate increased by 1.283 times, p<0.05; and when PCI was 0-20 points compared to 21-39 points, the 3-year overall survival rate increased by 1.772 times, p<0.05.
The scientific data on the radicality of surgical interventions has been clarified: for patients with stage III-IV ovarian cancer, transitioning from R1 to R0 radicality increases the 3-year overall survival rate by 1.211 times, p<0.05; transitioning from R2 to R0 increases the 3-year overall survival rate by 3.784 times, p<0.05; and transitioning from R2 to R1 increases the 3-year overall survival rate by 3.125 times, p<0.05. The scientific data regarding the dynamics of CA-125 reduction during NACT and the degree of therapeutic pathomorphosis (grades 0, I, II, III) have been expanded, with statistical significance established (p<0.05). Additional data have been obtained indicating that in cases of platinum-resistant ovarian cancer (stage III-IV), compared to platinum-refractory ovarian cancer (stage III-IV), the 3-year overall survival rate increases by 5.676 times, p<0.05.
A method for determining the radiological peritoneal carcinomatosis index (PCI) has been developed and implemented. Depending on the PCI level, decisions are made regarding tumor process verification (tumor trephine biopsy under ultrasound guidance or diagnostic laparoscopy) and the treatment strategy for the initial stage of therapy (surgical treatment or neoadjuvant chemotherapy courses). A protocol for administering 3 NACT cycles to patients with stage III-IV ovarian cancer has been developed and implemented, enabling a 1.29-fold reduction in PCI, shortening the duration of cytoreductive surgery without compromising surgical radicality, and avoiding an increase in intraoperative and postoperative complications. This approach has resulted in partial response or disease stabilization in 73 cases (92.4%) according to RECIST 1.1 criteria and facilitated the identification of platinum-refractory patients. Key words: ovarian cancer, tumor markers, radiological diagnostics, peritoneal carcinomatosis index, neoadjuvant chemotherapy, chemotherapy, paclitaxel, platinum-based drugs, cytoreductive surgery, complications, recurrences, progression-free survival, overall survival, quality of life. Branch-Medicina.
