Background: A wide variety of myelosuppressive chemotherapy regimens are used for the treatment of cancer in clinical practice. Neutropenic complications, such as febrile neutropenia, are among the most common side effects of chemotherapy, and they often necessitate delays or reductions in doses of myelosuppressive agents. Reduced relative dose intensity (RDI) may lead to poorer disease-free and overall survival. Methods: Using the McKesson Specialty Health/US Oncology iKnowMed electronic health record database, we retrospectively identified the first course of adjuvant or neoadjuvant chemotherapy received by patients without metastases who initiated treatment between January 1, 2007, and March 31, 2011. For each regimen, we estimated the incidences of dose delays (≥7 days in any cycle of the course), dose reductions (≥ 15% in any cycle of the course), and reduced RDI (<85% over the course) relative to the corresponding standard tumor regimens described in the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines). Results: This study included 16,233 patients with 6 different tumor types who received 1 of 20 chemotherapy regimens. Chemotherapy dose delays, dose reductions, and reduced RDI were common among patients treated in community oncology practices in the United States, but RDI was highly variable across patients, regimens, and tumor types (0.486–0.935 for standard tumor regimen cohorts). Reduced RDI was more common in older patients, obese patients, and patients whose daily activities were restricted. Conclusions: In this large evaluation of RDI in US clinical practice, physicians frequently administered myelosuppressive agents at dose intensities lower than those of standard regimens.
Neelima Denduluri, Debra A. Patt, Yunfei Wang, Menaka Bhor, Xiaoyan Li, Anne M. Favret, Phuong Khanh Morrow, Richard L. Barron, Lina Asmar, Shanmugapriya Saravanan, Yanli Li, Jacob Garcia, and Gary H. Lyman
Derek Weycker, Xiaoyan Li, Rich Barron, Hongsheng Wu, P.K. Morrow, Hairong Xu, Maureen Reiner, Jacob Garcia, Shivani K. Mhatre, and Gary H. Lyman
Background: Clinical practice guidelines recommend prophylaxis in patients with cancer receiving a colony-stimulating factor (CSF) when the risk of febrile neutropenia (FN) is high (>20%). For patients receiving chemotherapy regimens not documented as high-risk, the decision regarding CSF prophylaxis use can be challenging, because some patients may be at high risk based on a combination of the regimen and individual risk factors. Methods: A retrospective cohort design and US private health care claims data were used. Study subjects received chemotherapy regimens classified as “low” or “intermediate,” or unclassified, in terms of FN risk, and were stratified by cancer and regimen. For each subject, the first chemotherapy course, and each cycle and FN episode within the course, were identified. FN incidence proportions were estimated by the presence and number of risk factors and chronic comorbidities. Results: Across the 17 tumor/regimen combinations considered (n=160,304 in total), 74% to 98% of patients had 1 or more risk factor for FN and 41% to 89% had 2 or more. Among patients with 1 or more risk factor, FN incidence ranged from 7.2% to 29.0% across regimens, and the relative risk of FN (vs those without risk factors) ranged from 1.1 (95% CI, 0.8–1.3) to 2.2 (95% CI, 1.5–3.0). FN incidence increased in a graded and monotonic fashion with the number of risk factors and comorbidities. Conclusions: In this retrospective evaluation of patients with cancer receiving chemotherapy regimens not classified as high-risk for FN in US clinical practice, most patients had 1 or more FN risk factor and many had 2 or more. FN incidence was found to be elevated in these patients, especially those with multiple risk factors.