Background/Objectives: This study aimed to assess real-world toxicity and efficacy data of patients with early and advanced breast cancer (BC) who received treatment with abemaciclib. Methods: This was a prospective/retrospective multi-institutional collection of clinicopathological, toxicity, and outcome data from patients with early or metastatic hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative BC who received treatment with abemaciclib in combination with endocrine therapy in departments of oncology in Greece. Treatment combinations of abemaciclib with any endocrine therapy were accepted. The primary end point was toxicity rate in all patients of the study. Results: From June/2021 to May/2024, 245 women received abemaciclib/endocrine combination therapy; the median age was 57 years. Of these, 169 (69%) received abemaciclib as adjuvant therapy for early-stage disease, while 76 (31%) were treated for advanced BC. At the time of the data cutoff, 133 (84.7%) patients remained in the 2-year treatment period. The most common adverse event (AE) was diarrhea (51%), primarily Grade ≤ 2. Dose modifications due to AEs were required in 19.2% of cases, while treatment discontinuation occurred in 5.1%. There was no difference in dose modification/discontinuation rates between older patients (>65 years) and the remaining patients. For early-stage BC patients, the 2-year DFS and OS rates were 90.8% and 100%, respectively. In patients with advanced cancer (70, 30.8%), 1-year PFS and OS rates were 78% and 96.3%, respectively. Conclusions: This study confirms the safety and effectiveness of abemaciclib in alignment with registrational trials offering valuable insights into toxicity management and clinical outcomes in routine practice without identifying new safety concerns. Clinical Trial Registration: ClinicalTrials.gov NCT04985058.

Background: Breast cancer and gynecological malignancies, including cervical, ovarian, and endometrial cancers, remain leading causes of cancer incidence and mortality among women worldwide. This study investigated hereditary predisposition rates in women diagnosed with breast or gynecological cancer, focusing on the effect of age on pathogenic/likely pathogenic (P/LP) variant detection. We sought to determine whether younger age at diagnosis should be used as a criterion for patient selection for genetic testing. Methods: A total of 9084 consecutive females with breast cancer or gynecological tumors underwent NGS-based genetic testing (53 cancer-relevant genes) at Genekor laboratory from 2020-2026. Multivariable logistic regression evaluated factors associated with P/LP variant detection, adjusting for tumor type and family history. Results: Overall P/LP prevalence was approximately 20% (one in five patients), with tumor-specific rates of 19.24% in breast cancer, 27.59% in ovarian cancer, and 26.67% in endometrial cancer. P/LP prevalence declined significantly with age from 24.37% in patients <40 years to 15.90% in those ≥70 years, while VUS remained stable (40-43%). P/LP patients had earlier diagnosis (median 45 vs 46 years, p<0.001), driven predominantly by high-risk genes (13.87% in <40y vs 7.11% in ≥70y). BRCA1 showed stronger age enrichment than BRCA2 (8.14% vs 3.16% in <40y; median diagnosis 43 vs 45 years). Age remained independently associated with P/LP detection in multivariable analysis, with an 18% reduction in odds per 10-year increase for any P/LP (OR 0.82, 95% CI 0.78-0.86) and a stronger 28% reduction for high-risk variants (OR 0.72, 95% CI 0.67-0.78). Family history also independently predicted P/LP detection (OR 1.40, 95% CI 1.19-1.66). Conclusions: While younger patients have a higher prevalence of high-risk variants, clinically actionable findings were identified across all age groups, including patients ≥70 years These findings indicate that focusing on age to determine eligibility for genetic testing is insufficient. Expanding testing accessibility to individuals regardless of their age at diagnosis may enhance the identification of genetic cancer risk and optimize patient management.

Background: Breast cancer and gynecological malignancies, including cervical, ovarian, and endometrial cancers, remain leading causes of cancer incidence and mortality among women worldwide. This study investigated hereditary predisposition rates in women diagnosed with breast or gynecological cancer, focusing on the effect of age on germline pathogenic/likely pathogenic (P/LP) variant detection. We sought to determine whether younger age at diagnosis should be used as a criterion for patient selection for genetic testing. Methods: A total of 9084 consecutive females with breast cancer or gynecological tumors underwent germline NGS-based genetic testing (52 cancer-relevant genes) at Genekor laboratory from 2020–2026. Multivariable logistic regression evaluated factors associated with P/LP variant detection, adjusting for tumor type and family history. Results: Overall P/LP prevalence was approximately 20% (one in five patients), with tumor-specific rates of 19.24% in breast cancer, 27.59% in ovarian cancer, and 26.67% in endometrial cancer. P/LP prevalence declined significantly with age from 24.37% in patients <40 years to 15.90% in those ≥70 years, while Variants of Uncertain Significance (VUS) remained stable (40–43%). P/LP patients had earlier diagnosis (median 45 vs. 46 years, p < 0.001), driven predominantly by high-risk genes (13.87% in <40 y vs. 7.11% in ≥70 y). BRCA1 showed stronger age enrichment than BRCA2 (8.14% vs. 3.16% in <40 y; median diagnosis 43 vs. 45 years). Age remained independently associated with P/LP detection in multivariable analysis, with an 18% reduction in odds per 10-year increase for any P/LP (OR 0.82, 95% CI 0.78–0.86) and a stronger 28% reduction for high-risk variants (OR 0.72, 95% CI 0.67–0.78). Family history also independently predicted P/LP detection (OR 1.40, 95% CI 1.19–1.66). Conclusions: Although derived from a referral-based (and thus selected) population, these findings show that while younger patients have a higher prevalence of high-risk P/LP variants, clinically actionable findings are present across all age groups, including those ≥70 years. These results suggest that reliance on age alone to determine eligibility for genetic testing may be insufficient. Broadening access to testing beyond strict age-based criteria could improve the identification of hereditary cancer risk and inform patient management, although further evaluation in less selected populations is warranted.