Risk of hospitalization according to chemotherapy regimen in early-stage breast cancer

Abstract

Purpose: To compare the risk of hospitalization between patients with early-stage breast cancer who received different chemotherapy regimens.

Patient and methods: We identified 3,567 patients older than age 65 years from the SEER/Texas Cancer Registry-Medicare database and 9,327 patients younger than age 65 years from the MarketScan database who were diagnosed with early-stage breast cancer between 2003 and 2007. The selection was nonrandomized and nonprospectively collected. We categorized patients according to the regimens they received: docetaxel (T) and cyclophosphamide (C), doxorubicin (A) and C, TAC, AC + T, dose-dense AC + paclitaxel (P) or AC + weekly P. We compared the rates of chemotherapy-related hospitalizations that occurred within 6 months of chemotherapy initiation and used multivariable logistic regression analysis to identify the factors associated with these hospitalizations.

Results: Among patients younger than age 65 years, the hospitalization rates ranged from 6.2% (dose-dense AC + P) to 10.0% (TAC), and those who received TAC and AC + T had significantly higher rates of hospitalization than did patients who received TC. Among patients older than age 65 years, these rates ranged from 12.7% (TC) to 24.2% (TAC) and the rates of hospitalization of patients who received TAC, AC + T, AC, or AC + weekly P were higher than those of patients who received TC.

Conclusion: TAC and AC + T were associated with the highest risk of hospitalization in patients younger than age 65 years. Among patients older than age 65 years, all regimens (aside from dose-dense AC + P) were associated with a higher risk of hospitalization than TC. Results may be affected by selection biases where less aggressive regimens are offered to frailer patients.

Fig 1.

Chemotherapy regimen use according to year of diagnosis of patients with early-stage breast cancer (A) younger than age 65 years and (B) older than age 65 years. A, doxorubicin; C, cyclophosphamide; dd, dose dense; P, paclitaxel; T, docetaxel; w, weekly.

Fig 2.

(A) Proportions of patients with early-stage breast cancer younger than age 65 years (blue) and older than age 65 years (gold) hospitalized for chemotherapy-related reasons (neutropenia, fever, infection, thrombocytopenia, anemia, adverse effects of chemotherapy, dehydration, delirium) per chemotherapy regimen. (B) Hospitalization rates adjusted for granulocyte colony-stimulating factor primary prophylaxis. A, doxorubicin; C, cyclophosphamide; dd, dose dense; P, paclitaxel; T, docetaxel; w, weekly.