Patient-reported outcomes and symptom clusters pattern of chemotherapy-induced toxicity in patients with early breast cancer.

OBJECTIVE: This study aims to characterize patient-reported chemotherapy-induced toxicity in patients with breast cancer, determine its association with treatment regimens and patient characteristics, identify toxicity symptom clusters within a specific chemotherapy timeframe and analyze the correlation between symptom clusters within and between the timeframe to understand the changes and influences across chemotherapy. METHODS: Forty-six patient-reported toxicities during neoadjuvant/adjuvant chemotherapy for breast cancer were evaluated using adapted CTCAE version 4.0. Chi-Square/Fisher's Exact test was performed to analyze the difference in the incidence of toxicity symptoms by chemotherapy regimens. Poisson regression performed to assess factors associated with patient's total chemotherapy toxicity. Exploratory factor analysis (EFA) conducted to identify symptom clusters at T1 (first half) and T2 (second half of planned cycle). Factor scores were generated and Spearman correlation performed to explore the factor scores correlation between symptom clusters. RESULTS: A total of 142 patients with stage I-III breast cancer were included. The incidence of several toxicities differed significantly among three chemotherapy regimens. Subjects age ≥51 years are associated with lower number of reported toxicity (IRR/incidence rate ratio = 0.94, 95% confidence interval/CI 0.88 to 0.99, p = 0.042). Receiving more chemotherapy cycles are associated with higher number of reported toxicity (IRR = 1.06, 95% CI 1.03 to 1.10, p<0.001). Two symptom clusters identified at T1 (psychoneurological-pain/PNP-T1 and gastrointestinal-psychological/GIP-T1 cluster) and three at T2 (psychoneurological-pain/PNP-T2, epithelial/EPI-T2, and gastrointestinal cluster/GI-T2), with moderate-strong positive correlation between PNP-T1 and GIP-T2 (p<0.001), PNP-T1 and PNP-T2 (p<0.001), and GIP-T1 and PNP-T2 (p<0.001). CONCLUSIONS: This study investigated 46 patient-reported toxicities prospectively during adjuvant/neoadjuvant chemotherapy for early breast cancer. Anthracycline-taxane combination regimen had higher proportions of toxicity incidence. Subject's age and number of chemotherapy cycles significantly associated with total number of toxicity symptoms. Two symptom clusters at T1 and three at T2 were identified, with significant correlation between symptom clusters within and between chemotherapy timeframe.

Chemotherapy-Induced Nausea and Vomiting in Patients With Breast Cancer: Risk Factor and Predictive Model Using Classification and Regression Tree (CART).

Introduction Chemotherapy-induced nausea and vomiting (CINV) is a common and debilitating adverse effect of breast cancer chemotherapy. The incidence of CINV in the first cycle of chemotherapy is essential, as it sets the tone for anticipatory CINV and the overall patients' treatment experience. We aimed to investigate the risk factors of first cycle CINV in breast cancer patients and to develop a classification and regression tree (CART) model to predict its occurrence. Methods This is a cross-sectional study that nested in a prospective cohort. One hundred and thirty-seven female breast cancer patients receiving highly emetogenic chemotherapy were included. We used the Common Toxicity Criteria for Adverse Events (CTCAE) version 4.0 to assess patient-reported nausea and vomiting in the first chemotherapy cycle. The proportional difference of CINV between sociodemographic and clinicopathologic variables was analyzed using chi-square, and the strength and direction of the relationship with CINV were analyzed using bivariable logistic regression analysis. Multivariable logistic regression and CART analysis included variables with a p-value <0.250. Results The incidence of first-cycle CINV was 43.1%. The chi-square test revealed a significant association between insurance status and CINV (p<0.001) and between the stage at diagnosis and CINV (p<0.001). Underweight to normal body mass index (BMI) patients are significantly associated with an increased risk of first-cycle CINV (OR =2.17, 95% CI 1.03-4.56, p =0.041). In hierarchical order, three variables (stage at diagnosis, BMI, and age) were included in the CART model, which significantly influenced the probability of first cycle CINV. With an accuracy of 61.3%, the CART model had a sensitivity of 28.8%, a specificity of 85.9%, a positive predictive value of 60.7%, a negative predictive value of 61.5%, and an area under curve (AUC) of 0.602.  Conclusion Breast cancer patients with an underweight to normal BMI have a higher risk of developing first-cycle CINV. Our CART model was better at identifying patients who would not develop CINV than those who would. The CART model may provide a simple and effective way to individualize patient care for first-cycle CINV.

The occurrence and risk factors of chemotherapy-induced neutropenia in patients with breast cancer not receiving primary G-CSF prophylaxis.

Background: Chemotherapy-induced neutropenia (CIN) is a substantial side effect in chemotherapy of breast cancer patients. Administration of granulocyte colony stimulating factor (G-CSF) that may reduce CIN occurrence is not commonly available to many local cases. Objectives: To investigate the occurrence of grade 4 CIN and the influencing factors in breast cancer patients not receiving G-CSF prophylaxis. Methods: One-hundred and eighty-six newly diagnosed breast cancer patients who received a 3-weekly (neo)adjuvant or palliative chemotherapy without primary G-CSF prophylaxis were included. Grade 4 CIN was defined as absolute neutrophil count (ANC) <0.5 × 103/mm3 during any chemotherapy cycle. We used logistic regression to explore the association of clinical, pathological and treatment factors with the risk of grade 4 CIN in the first cycle and in any given cycle. Results: Fifty-seven (30.6%) patients experienced grade 4 CIN in the first cycle and 145 (78%) had it at least once during chemotherapy. In the first cycle, haemoglobin, ANC, and albumin levels were associated with grade 4 CIN (OR = 1.48, p = 0.031; OR = 0.68, p = 0.006; and OR = 2.07, p = 0.042). In any cycle, pre-treatment ANC levels and anthracycline-taxane combination regimen were associated with grade 4 CIN (OR = 0.78, p = 0.032 and OR = 3.64, p = 0.012). Conclusions: A significant proportion of the local breast cancer cases undergoing chemotherapy without primary G-CSF prophylaxis experienced grade 4 CIN. Haemoglobin, ANC, and albumin levels are the risk factors for first cycle CIN, while pre-treatment ANC levels and anthracycline-taxane chemotherapy regimen are associated with CIN in any given cycle. These risk factors may be used to direct a recommendation of G-CSF prophylaxis to the most at-risk individuals in the local setting or other settings in similar situations.