Introduction: Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly changed the treatment strategy for patients with locally advanced or metastatic hormone receptor positive (HR+), human epidermal growth factor 2 negative (HER2) breast cancer. The purpose of the study was to determine the prevalence of drug-drug interactions (DDI) in breast cancer patients using CDK 4/6 inhibitors and the extent of DDI reflected in the clinic and to increase clinical awareness among physicians. Method: The data of 115 metastatic breast cancer patients using CDK 4/6 inhibitors who were admitted to the Medical Oncology outpatient clinic between July 2021 and July 2023 were retrospectively reviewed. The Drugs.com® Drug Interaction Checker application was used for the interaction between the CDK 4/6 inhibitor and other drugs. Results: Among patients included in the study, 97.3% had at least one additional drug use. We have identified a total of 170 potential DDI risks in 63.5 % of patients. Among these, 50.5% had a major potential DDI. In our study, there was a potential risk of QT prolongation in 45.2% of 170 DDI, an increase in the potential toxicity of the additional drug in 44.1%, an increase in the potential toxicity of the CDK 4/6 inhibitor in 5.3%, a decrease in the potential efficacy of the CDK 4/6 inhibitor in 2.9%, a decrease in the potential efficacy of the additional drug in 1.1%, and a serious potential infection risk in 1.1%. Most of the drug interactions were QT prolongation and increased toxicity of the additional drug. In terms of cardiovascular events, grade-2 and grade-3 QTc prolongation was found in 4.3% and 1.7% of these interactions, respectively. When evaluated in terms of CDK 4/6 inhibitor subtype, there was a potential risk of DDI at major level with Ribocilib and at moderate level with Palbociclib. Conclusion: If CDK 4/6 inhibitors interact with concomitant drugs, they may cause an increase in the incidence of cardiac side effects and a decrease in the effect of the CDK 4/6 inhibitor or additional drug or an increase in toxicity. Increasing awareness of this issue will help to reduce the rates of side effects or toxicity and provide effective antitumour therapy.

Angiosarcomas originating from the gastrointestinal tract are rare but highly aggressive tumors with poor prognosis. These tumors can be misdiagnosed as benign and malignant gastrointestinal tract lesions. The definitive histological diagnosis of angiosarcomasis made by pathologists based on immunohistochemical analysis demonstrating cluster of differentiation 31 (CD31), factor VIII-related antigen (FVIIIRAg), erythroblast transformation specific related gene (ERG), and cluster of differentiation 34 (CD34). Angiosarcomas are treated with a single or multimodality approach that may include resection, radiotherapy, chemotherapy, and palliative care, depending on the stage of disease and the condition of the patient. No matter the treatment option, metastasis and death rates are substantially highin patients with angiosarcoma. In this context, a 59-year-old male with synchronous double primary angiosarcoma arising from the gastric and rectum who presented with the complaint of abdominal pain and distention to the outpatient clinic is presented in this case report, along with a brief literature review.

Introduction: Cyclin-dependent kinase (CDK) 4/6 inhibitors are widely used in combination with aromatase inhibitors or fulvestrant for the treatment of locally advanced or metastatic hormone receptor-positive (HR+), human epidermal growth factor 2-negative (HER2-) breast cancer. Hematological toxicities (e.g. neutropenia, thrombocytopenia, anemia, lymphopenia, or febrile neutropenia), infections, decreased appetite, exhaustion, headache, dizziness, cough, nausea, vomiting, diarrhea, alopecia, rash, increased alanine aminotransferase and aspartate aminotransferase levels, and QT interval prolongation are frequent side effects associated with the use of CDK 4/6 inhibitors. However, to our knowledge, no case of hallucination associated with CDK 4/6 inhibitor use has been described in the English-language literature. Case report: We report a case of a 72-year-old woman with metastatic breast cancer who developed visual hallucinations after receiving ribociclib, a CDK 4/6 inhibitor, and letrozole for 3 days. Cranial imaging and blood tests did not reveal the cause of the hallucinations. Management and outcome: The visual hallucinations completely resolved within 4 days after the ribociclib treatment was terminated. The patient received only letrozole for 2 weeks, and ribociclib treatment was restarted 2 weeks later. Visual hallucinations recurred on the third day of treatment, and ribociclib treatment was discontinued again. The patient recovered completely from visual hallucinations 4 days after discontinuation. Subsequently, treatment was continued with letrozole and palbociclib, another CDK 4/6 inhibitor. Hallucinations did not recur during follow-up. Discussion: To our knowledge, this is the first reported case of hallucinations caused by ribociclib; notably, it shows that symptoms may develop in the early stage of treatment.

Colorectal cancer is a common and often fatal malignancy, and predicting survival can help guide treatment decisions. This study aimed to investigate the impact of clinicopathological characteristics and nutritional status on survival in patients with metastatic colorectal cancer receiving first-line treatment with 5-fluorouracil in combination with monoclonal antibodies (bevacizumab, cetuximab, or panitumumab). This prospective, non-interventional, observational, single-center study included 150 adult patients with metastatic colorectal cancer undergoing first-line therapy. Demographic data, cancer-related characteristics, laboratory parameters, and nutritional status assessed via the Mini Nutritional Assessment-Short Form were recorded prior to treatment initiation. Mini Nutritional Assessment-Short Form scores of 12-14, 8-11, and 0-7 were used to define normal nutritional status, risk of malnutrition, and malnutrition, respectively. The mean ages of patients without and with malnutrition were 60±11 and 62±11 years, respectively. Median progression-free survival and overall survival were 12 and 22 months, respectively. Multivariate analysis identified alcohol history (HR=2.83; 95%CI 1.27-6.34; p=0.011) and Mini Nutritional Assessment-Short Form≤7 (HR=1.93; 95%CI 1.09-3.45; p=0.025) as significant predictors of shorter progression-free survival. Mini Nutritional Assessment-Short Form ≤7 (HR=2.96; 95%CI 1.80-4.89; p<0.001) was also significantly associated with decreased overall survival. Among patients with metastatic colorectal cancer receiving first-line therapy, malnutrition (Mini Nutritional Assessment-Short Form≤7) and a history of alcohol use were associated with poorer survival outcomes. These findings underscore the importance of routine nutritional assessment and support the need for further prospective multicenter studies to validate these results.

Background: Hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer frequently involves liver metastases, which are linked to poor outcomes. The optimal first-line treatment strategy in this subgroup remains unclear. Methods: This multicenter, retrospective study evaluated 121 patients with HR-positive, HER2-negative breast cancer and liver metastasis who had not received prior systemic chemotherapy or cyclin-dependent kinase (CDK) 4/6 inhibitors (e.g., palbociclib, ribociclib). Patients were classified based on their initial treatment during the liver metastatic phase (CDK4/6 inhibitors or chemotherapy). Clinical characteristics, treatment patterns, and survival outcomes were assessed. Cox regression analysis identified independent prognostic factors. Results: The median age was 53 years; 62% were postmenopausal. Chemotherapy was administered to 36.4%, and CDK4/6 inhibitors to 63.6% of patients. Most cases (59.5%) were recurrent disease. Baseline characteristics were comparable, except for the use of local liver-directed therapies. Progression-free survival favored CDK4/6 inhibitors (10.9 vs. 4.8 months; p < 0.01), while overall survival favored chemotherapy (42.2 vs. 25.9 months; p = 0.042). In multivariate analysis, initial treatment modality, local liver-directed therapy, hormonal status, and the size of the largest liver lesion were independent predictors of survival. Conclusions: In patients with HR-positive, HER2-negative breast cancer and liver metastasis, first-line chemotherapy was associated with improved overall survival compared to CDK4/6 inhibitors. Local liver-directed therapies contributed to longer survival, while larger liver lesions and endocrine-resistant disease correlated with worse outcomes. These findings support considering chemotherapy as first-line treatment in selected patients with aggressive liver metastatic disease.