Background: Pathological complete response (pCR) following neoadjuvant therapy (NAT) is a key surrogate marker for long-term outcomes in HER2-positive breast cancer. Identifying clinical and biological predictors of pCR, including systemic inflammatory and nutritional markers such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), neutrophil-to-albumin ratio (NAR), C-reactive protein-to-albumin ratio (CAR), systemic immune-inflammation index (SII), and prognostic nutritional index (PNI), may help refine treatment strategies and improve patient outcomes. Methods: We retrospectively analyzed 174 patients with stage II–III HER2-positive breast cancer who received neoadjuvant anti-HER2-based regimens at multiple centers between 2010 and 2025. Demographic, clinicopathological, and laboratory data were collected, and inflammatory and nutritional indices (NLR, PLR, LMR, NAR, CAR, SII, PNI) were calculated. Predictors of pCR were evaluated using univariate and multivariate logistic regression analyses. Results: Overall, 49% of patients achieved pCR. In multivariate analysis, independent predictors of pCR were hormone receptor negativity, smaller tumor size, HER2 IHC 3+ expression, dual HER2 blockade, and a higher prognostic nutritional index (PNI ≥ 55). In contrast, systemic inflammatory indices such as NLR, PLR, LMR, NAR, CAR, and SII were not significantly associated with pCR. Conclusions: This multicenter real-world study demonstrates that conventional inflammatory markers have limited predictive value, whereas the PNI emerges as a simple and practical biomarker reflecting nutritional and immune status. Integrating PNI with clinicopathological factors may enhance risk stratification and help guide individualized neoadjuvant treatment strategies in HER2-positive breast cancer.

Adjuvant chemotherapy decision-making in stage II colon cancer remains challenging. Although multidisciplinary tumor boards (MDTs) guide treatment, their recommendations vary. Artificial intelligence (AI) tools such as ChatGPT may support decision-making, but direct comparative evidence with MDTs is limited. We retrospectively analyzed 179 patients with stage II colon cancer who underwent surgery between 2019-2024. MDT recommendations (observation, fluoropyrimidine monotherapy, or oxaliplatin-based chemotherapy) were compared with ChatGPT-5 outputs. Clinical factors - including age, ECOG performance status (PS), tumor stage, minor risk factors, and mismatch repair (MMR) status - were incorporated. Agreement was evaluated using Cohen's kappa (κ) and McNemar's test. Across the three treatment categories, agreement between MDT and AI was moderate (70.4%, κ = 0.542, p < 0.001), while in the binary comparison of adjuvant therapy versus observation, concordance improved to substantial (91.1%, κ = 0.719, p < 0.001). Discordance mainly reflected AI's tendency to escalate therapy. Agreement decreased in patients ≥70 years, those with ECOG PS 2, and those with multiple risk factors. AI showed moderate agreement with MDTs in detailed three-category recommendations but substantial concordance in binary adjuvant decisions. While AI may serve as a supportive tool, clinical judgment remains essential, particularly for elderly and frail patients.

Background and Objectives: Breast cancer is a leading cause of cancer-related mortality, particularly in aggressive subtypes such as HER2-positive and triple-negative breast cancer (TNBC). Achieving a pathological complete response (pCR) after neoadjuvant therapy is strongly associated with improved survival outcomes in these subgroups, making the prediction of pCR a clinical priority. Sarcopenia, a progressive loss of skeletal muscle mass and strength, is increasingly recognized in cancer patients and has been linked to chemotherapy toxicity and poorer survival. However, its specific impact on pCR in HER2-positive and TNBC patients remains unclear. This study aimed to evaluate the association between radiologically defined sarcopenia, or a low skeletal muscle index (SMI), and pathological response in these subtypes, and to explore its potential as a predictive biomarker. Materials and Methods: This retrospective study included patients with HER2-positive or TNBC who received neoadjuvant therapy between January 2015 and October 2023. SMI was assessed using pre-treatment positron emission tomography images at the L3 vertebral level, with values < 38.5 cm²/m² considered as low. Univariate and multivariate logistic regression analyses were performed to identify factors associated with pCR. Results: A total of 85 patients were included, with low SMI present in 35 (41.2%). In univariate analysis, clinical stage and low SMI were associated with pCR. However, in the multivariate model, only low SMI remained an independent predictor. Patients without low SMI had higher odds of achieving pCR (odds ratio [OR] 4.13; 95% confidence interval [CI] 1.55–10.95; p = 0.004). Low SMI was also associated with higher rates of treatment-related toxicity (42.9% vs. 20.0%, p = 0.023). Conclusions: Pre-treatment low SMI is strongly associated with lower pCR rates in patients with HER2-positive and TNBC undergoing neoadjuvant therapy. These findings underscore the importance of early identification and management of radiologically defined sarcopenia to optimize treatment response and improve clinical outcomes.

Background/Objectives: Uveal melanoma (UM) is a subtype of melanoma that originates from the uveal layer of the eye (iris, ciliary body, choroid) and is biologically distinct from cutaneous melanoma. The real-world evidence on treatment patterns and survival outcomes, particularly from non-Western populations, remains limited. This study provides a comprehensive national overview of local and systemic management of UM across Türkiye. Methods: This multicenter retrospective cohort study, coordinated by the Turkish Oncology Group (TOG), included patients diagnosed with UM between 2012 and 2025 across 19 tertiary oncology centers. Clinical characteristics, treatment patterns, and outcomes were analyzed. Systemic therapies were subgrouped as immunotherapy or cytotoxic chemotherapy. Progression-free survival (PFS) and overall survival (OS) were assessed by the Kaplan–Meier method; prognostic factors for OS were analyzed by Cox regression. Results: A total of 113 patients were included; 89.4% presented with localized disease. During follow-up, 43.4% developed metastases, predominantly hepatic (93.5%). 47.4% of metastatic patients received liver-directed treatments; the most common treatment was radioembolization, and these treatments were associated with longer OS. Among 59 patients receiving systemic therapy, immunotherapy demonstrated higher ORR and DCR than chemotherapy across treatment lines, although small subgroup sizes limited statistical significance. Dual immune checkpoint blockade emerged as an independent favorable prognostic factor in multivariate analysis. Median OS for metastatic patients was 16 months (95% CI: 9.3–22.7). HLA-A*02:01 was positive in 29.4% of patients tested, and only three patients received tebentafusp. Conclusions: This large national cohort highlights substantial real-world heterogeneity in treatment patterns and confirms the limited efficacy of chemotherapy, the prognostic benefit of dual ICI therapy, and the potential survival advantage of liver-directed treatments in selected patients. Low HLA-A*02:01 positivity and limited access to tebentafusp remain major challenges in Türkiye. These findings provide an essential benchmark for improving treatment strategies in metastatic UM.

Background: This retrospective study compared the effectiveness and preliminary cost evaluation of denosumab and zoledronic acid (ZA) in patients with bone metastases from breast, prostate, and lung cancer. Methods: Patients treated with ZA or denosumab between January 2016 and August 2023 were analyzed. Outcomes included the incidence of skeletal-related events (SREs), time to first SRE, and cost per prevented SRE. An incremental cost-effectiveness analysis (ICER framework) was also performed, using prevention of SREs as the effectiveness outcome. Results: A total of 192 patients in the denosumab group and 239 in the ZA group were included. Denosumab significantly reduced the incidence of SREs compared with ZA (34.8% vs. 51.8%, p < 0.001). The median time to first SRE was longer with denosumab (34.5 vs. 29.1 months), but the difference was not statistically significant (p = 0.593). Stratified analyses showed significant benefit in breast (29.5% vs. 49.2%, p = 0.002) and prostate cancer (43.9% vs. 66.0%, p = 0.035), but not in lung cancer (39.1% vs. 45.9%, p = 0.484). Denosumab was more costly, with an additional USD 4686 per prevented SRE. Conclusions: Denosumab was more effective than ZA in reducing SREs, particularly in breast and prostate cancer patients, but it was associated with higher costs. These findings should be interpreted as preliminary due to the retrospective design and the absence of QALY-based outcomes.

Background and Objectives: The prognostic significance of body mass index (BMI) in metastatic HER2-positive breast cancer (BC) remains unclear, with previous studies yielding conflicting results. This multicenter real-world study aimed to investigate the prognostic role of BMI in this patient population. Materials and Methods: A total of 169 female patients with metastatic HER2-positive BC who received trastuzumab-based treatment between 2010 and 2024 were included. Patients were categorized by BMI (<30 kg/m² vs. ≥30 kg/m²). The primary endpoints were overall survival (OS) and progression-free survival (PFS). Kaplan–Meier and Cox regression analyses were performed overall and in subgroups stratified by hormone receptor (HR) status. Results: In the overall cohort, a BMI ≥ 30 was not significantly associated with OS or PFS. However, in the HR-positive/HER2-positive subgroup, BMI ≥ 30 kg/m² was linked to significantly shorter OS (p = 0.024) and PFS (p = 0.047) by Kaplan–Meier analysis. However, these associations did not remain statistically significant in multivariate analyses. No significant BMI-related differences were observed in the HR-negative subgroup. Other independent negative prognostic factors included recurrent disease, the presence of brain metastases, and a high Ki-67 index. Conclusions: BMI was not identified as an independent prognostic factor in the overall population. However, among HR-positive/HER2-positive patients, obesity was associated with poorer survival in univariate analysis, but this was not confirmed in multivariate analysis. These findings underscore the need for prospective studies to clarify the prognostic role of adiposity, considering biological subtypes.