GCSF primary prophylaxis reduces febrile neutropenia and hospitalization in docetaxel-treated breast cancer patients

The use of granulocyte colony-stimulating factors (GCSFs) as primary prophylaxis (PP) reduces the incidence of febrile neutropenia (FN) and associated hospitalization among breast cancer patients receiving docetaxel-containing chemotherapy, with 4–5 days of PP offering similar efficacy and greater healthcare expenditure savings vs 7-day PP, results of a retrospective cohort study in Hong Kong have shown.

“Further utility and economic analysis could be considered to evaluate the effectiveness of using GCSF as PP in reducing the risk of FN and associated hospitalization in public hospitals in Hong Kong,” suggested the researchers. [Support Care Cancer 2020;28:3801-3812]

In the study, researchers retrieved data of 2,518 breast cancer patients (mean age, 53.62 years; female, 99.8 percent) who had received docetaxel-cyclophosphamide (TC; n=855), doxorubicin-cyclophosphamide followed by docetaxel (AC-T; n=372), fluorouracil-epirubicin-cyclophosphamide followed by docetaxel (FEC-T; n=925), docetaxel-carboplatin-trastuzumab (TJH; n=257), or docetaxel-doxorubicin-cyclophosphamide (TAC; n=109) from 1 January 2014 to 31 December 2016 through the Query Template System in Pharmacy Management System. GCSFs were offered within 5 days of administering docetaxel-containing regimens.

About half (52.90 percent) and 28.51 percent of the patients had stage II and III disease, respectively, and these patients were predominately managed by TJH, FEC-T, AC-T or TAC. FEC-T was used mostly in nodal-positive breast cancer patients (82.9 percent for 0-day PP; 81.6 percent for 4- or 5-day PP; 81.9 percent for 7-day PP).

More treatment delay (of at least one cycle) and chemotherapy dosage adjustment were required in patients on 4- or 5-day PP than those on 0-day PP or 7-day PP (treatment delay, 19.2 percent vs 6.6 percent vs 13.1 percent) (dosage adjustment, 10.9 percent vs 5.1 percent vs 5.5 percent).

The incidence of FN was 23.3 percent, 6.50 percent and 9.01 percent in patients on 0-day PP, 4- or 5-day PP and 7-day PP, respectively.

The use of PP led to significant reductions in the risk of FN vs 0-day PP in the entire cohort (p<0.001; number needed to treat [NNT], 6 for 4- or 5-day PP and 7 for 7-day PP) and across most treatment groups (p>0.035), except for those on 7-day PP within the FEC-T group (p=0.396) and the AC-T group (p=0.564).

Comparable reductions in risk of FN were observed between patients on 7-day PP and 4- or 5-day PP across most treatment groups (p>0.190), except for those in the AC-T group (p=0.007), in which 7-day PP was associated with a 2.76-fold increase in the risk of FN (95 percent confidence interval, 1.32 to 5.78) compared with 4- or 5-day PP.

Overall, the use of 4- or 5-day PP and 7-day PP was associated with a significant reduction in mean time to first hospitalization as a result of FN compared with 0-day PP (7.64 days vs 7.63 days vs 9.37 days; both p<0.001), without an increase in the number of days of hospitalization (4.37 days vs 5.12 days vs 4.66 days).

The use of 4- or 5-day PP in patients treated with TC, TJH or AC-T was associated with a cost saving of USD 90.7, USD 376.7 and USD 241.7 per patient with FN, respectively, compared with 0-day PP. “The cost savings translated to a reduction in healthcare resource utilization with a lowered incidence of FN,” said the researchers. “The savings in healthcare expenditure was of particular importance in patients treated with TJH, who were found to have a higher incidence of FN, and to a lesser extent, in those treated with FEC-T.”