Background: Poly(ADP-ribose) polymerase (PARP) inhibitors have been established as a first-line maintenance therapy in advanced epithelial ovarian cancer (EOC) following platinum-based chemotherapy. While phase III trials have demonstrated significant progression-free survival (PFS) benefits with olaparib and niraparib, real-world data remain limited. Methods: This retrospective, multicenter real-world study included 179 patients with newly diagnosed epithelial ovarian treated with first-line maintenance olaparib or niraparib across 33 centers in Türkiye between January 2014 and March 2025. Clinical, pathological, and molecular data—including BRCA (Breast Cancer Susceptibility Gene) mutation status, origin, and variant classification—was collected. The primary endpoint was PFS, and secondary endpoints included overall survival (OS) and safety. Survival outcomes were analyzed using Kaplan–Meier methods. Results: Of 179 patients, 110 received olaparib and 69 received niraparib. BRCA mutations were present in 88.3% of patients, while 11.7% had unknown HRD status. Median follow-up was 16.5 months, and median PFS was not reached. Estimated PFS rates for the overall cohort were 91.0% at 6 months, 83.0% at 12 months, and 64.0% at 24 months. In the olaparib cohort, BRCA-mutant patients demonstrated PFS rates of 89%, 78%, 73%, and 64% at 6, 12, 18, and 24 months, respectively. In the niraparib cohort, corresponding PFS rates among BRCA-mutant patients were 87% at 6 months and 75% at 12 months. Patients harboring pathogenic BRCA variants experienced longer PFS compared with those with likely pathogenic variants. Any-grade adverse events occurred in 73.7% of patients, and grade 3–4 events in 29.6%, with hematologic toxicities predominating. Dose interruptions were more frequent with niraparib, while treatment discontinuation rates were low in both groups. No cases of myelodysplastic syndrome or acute myeloid leukemia were observed. Conclusions: In this large multicenter real-world cohort, first-line maintenance therapy with olaparib and niraparib provided durable PFS benefit in patients with advanced EOC, particularly among those with pathogenic BRCA mutations, confirming their effectiveness and manageable safety profiles in routine clinical practice.

Background and Objectives: Axillary lymph node (ALN) status is one of the most important prognostic factors in breast cancer. Numerous studies have evaluated less invasive methods for accurate staging. To investigate the diagnostic performance of ultrasound (US), mammography, and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in predicting axillary lymph node metastasis in breast cancer patients. Materials and Methods: Axillary involvement detected by US, mammography, and ¹⁸F-FDG PET/CT was analyzed in patients who underwent axillary dissection. Preoperatively, 365, 318, and 85 of 557 patients were evaluated with US, mammography, and PET/CT, respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of each imaging modality were calculated. Results: The sensitivity, specificity, PPV, NPV, and accuracy of US were 33.3%, 97.5%, 94.4%, 51.0%, and 57.8%, respectively. False-negative US findings were more frequent in T1 (84.6%) and N1 (76.3%) tumors (p < 0.001 for both). For mammography, these values were 12.9%, 97.74%, 88.89%, 44.67%, and 52.9%, while for ¹⁸F-FDG PET/CT they were 72.5%, 100%, 100%, 67.65%, and 82.5%, respectively. Conclusions: Ultrasound remains useful for evaluating axillary lymph node involvement in advanced breast cancer but is insufficient for early-stage disease.

Background: Achieving no evidence of disease (NED) in HER2-positive metastatic breast cancer (MBC) has been proposed as a response-state marker for durable disease control. However, its clinical significance and predictive factors are not yet well established. Methods: In this multicenter retrospective study at 13 oncology centers in Turkey, we analyzed 118 patients with stage IV HER2-positive MBC who received trastuzumab-based first-line therapy and remained progression-free for at least 36 months. Patients were stratified by radiologically defined NED status according to RECIST v1.1. Clinicopathological features were compared between groups, and predictors of NED were identified using logistic regression. Progression-free survival (PFS) was estimated by Kaplan–Meier analysis and assessed with Cox regression. Results: Of the 118 patients, 55 (46.6%) achieved NED. Compared with patients who did not achieve NED, those attaining NED were younger (median 46 vs. 53 years, p = 0.013), had better ECOG performance status (p = 0.005), were more likely to have HER2 IHC 3+ status (p = 0.015), and higher histologic grade tumors (p = 0.013). In multivariable logistic regression, ECOG PS 0 (vs. 1 ; OR = 5.99, p = 0.005), HER2 IHC 3+ (vs. IHC 2+/ISH+; OR = 4.79, p = 0.035), and histologic grade ≤2 (vs. grade 3 ; OR = 0.25, p = 0.011) were independently associated with NED attainment. Patients who achieved NED had experienced significantly longer PFS than those who did not (median 131 months vs. 66 months; p < 0.005). In multivariate Cox regression, NED remained independently associated with prolonged PFS (HR = 0.24, p = 0.003). Metastasis-directed local therapy and treatment regimen (trastuzumab vs. trastuzumab + pertuzumab) were not independently associated with NED attainment or PFS. Conclusions: In this multicenter cohort of pre-selected long-term responders, nearly half of HER2-positive MBC patients achieved radiologic NED. Radiologic NED was independently associated with prolonged PFS within this enriched population. Factors associated with NED attainment included favorable ECOG performance status, HER2 IHC 3+ expression, and high tumor grade; given the wide confidence intervals, these estimates should be interpreted cautiously as exploratory and hypothesis-generating.