Comparing risk models guiding growth factor use in chemotherapy
Background The National Comprehensive Cancer Network (NCCN) and the American Society of Clinical Oncology (ASCO) have guidelines for using colony-stimulating factors (CSF) for chemotherapy-induced neutropenia (CIN). Both groups recommend CSF if the chemotherapy has a risk for febrile neutropenia of more than 20%. The guidelines are less definitive if the risk is intermediate (10%-20%). Two risk models developed by Hosmer and Bozcuk and their respective colleagues may provide guidance regarding CSF decision making in this intermediate risk population.
Objective To examine whether risk models developed by Hosmer and Bozcuk had adjunct value to the NCCN and ASCO guidelines when applied to patients with lung cancer who were receiving intermediate-risk chemotherapy.
Methods Male and female patients aged 18-75 years with a diagnosis of any stage lung cancer, small or non-small cell, who required and received their initial chemotherapy at Drexel University in Philadelphia were included in this study. Patients who received growth factor before their chemotherapy were excluded. The Hosmer and Bozcuk calculators for febrile neutropenia risk and the NCCN and ASCO guidelines for using CSF for CIN were applied to this group of patients.
Results 43 patients were included in the study. The Hosmer and Bozcuk calculators and NCCN and ASCO guidelines recommended giving CSF to 26, 22, 25, and 38 patients, respectively. The sensitivities for detecting severe CIN were 89%, 78%, 67%, and 97%, and the specificities were 44%, 56%, 45%, and 14%, respectively.
Limitations Small cohort size; data were limited in scope.
Conclusions In lung cancer patients receiving intermediate-risk chemotherapy, the Hosmer calculator had the best combination of sensitivity, specificity, and ease of use. The NCCN guidelines were less sensitive, whereas the ASCO guidelines were the least specific. Based on these findings, we recommend using the Hosmer calculator because it lends to accurate but judicious use of CSF.
Accepted for publication November 2, 2018
Correspondence Chetan Jeurkar, DO; jeurkar2@gmail.com
Disclosures The authors report no disclosures/conflicts of interest.
©2018 Frontline Medical Communications
doi https://doi.org/10.12788/jcso.0429
Current guidelines
NCCN guidelines. If one were to use the NCCN guidelines on our cohort of 43 patients, 25 would have been recommended to receive prophylactic CSF. Of those 25, 6 developed severe CIN (2 with FN), 2 moderate CIN, and 5 mild CIN. Of the 18 patients who would not have been recommended to receive CSF, 3 developed severe CIN (with 2 FN), 2 moderate CIN, and 3 mild CIN. Sensitivity and specificity values are listed in Table 2.
ASCO guidelines. Using the ASCO guidelines on our cohort of 43 patients, 38 had 1 or more of the high-risk features, and, therefore, CSF would have been considered for them. Of those 38 patients, 8 developed severe CIN (4 with FN), 4 developed moderate CIN, and 7 developed mild CIN. Of the 5 patients who would not have received CSF, 1 developed severe CIN and 1 mild CIN. Sensitivity and specificity values are listed in Table 2.
Discussion
In our study, we looked at 2 CIN risk models and compared them with the current NCCN and ASCO guidelines. The models were created to predict risk of FN, but we also looked at their predictive value for any level of CIN. To this end, we found that the Hosmer and Bozcuk calculators both were acceptable for predicting risk of severe CIN and FN. Because of the small number of patients in this study, differences in sensitivities and specificities cannot be quantitatively compared. Nevertheless, qualitatively, it can be said that both calculators were accurate in assigning high-risk scores to patients who developed severe CIN or FN. However, both calculators had many patients with high-risk scores who never developed CIN.
,When comparing the 2 risk models with the NCCN and ASCO guidelines, the ASCO guidelines tended to be more liberal in their consideration of CSF use, whereas the NCCN guidelines tended to be more conservative and more similar to the 2 risk models we tested. The NCCN guidelines suggested not giving prophylactic CSF to 2 of our patients who developed FN and to not give CSF to an additional patient who developed severe CIN. The ASCO guidelines suggested considering using CSF for most of our patients, with only 5 patients not to be considered for CSF administration.
The differences in efficacy between the current guidelines and the 2 risk models may be indicative of the fact that the risk models are more accurate in assigning risk in older patients who are clinically more complicated. In our patients, the chemotherapies used were all considered to be intermediate risk, so patient-specific factors were used to guide the administration of CSF. However, because many our patients had at least 1 of the risk factors listed by the NCCN or ASCO, they were automatically deemed to be high risk and to receive prophylactic CSF.
Consequently, the Hosmer and Bozcuk calculators may be of greatest utility in more clinically complicated patients and those who have more comorbidities. The best approach may be a combination of either the NCCN or ASCO guidelines with 1 of the calculators, in our opinion the Hosmer system, for these complicated patients. Likely, the 2 risk models would not be as useful for chemotherapies deemed to have a high risk for FN because, in those situations, the efficacy and benefit of prophylactic CSF are clear. 9 Rather, their use could be beneficial in the grayer areas in which the risk is intermediate and decision-making is more difficult.
