This study shows the economic impact of FN jointly with the demographics and clinical characteristics of this population, showing high compliance with the clinical guidelines  and the administered antibiotics, antifungal, imaging, and laboratory tests. These occurred mainly in advanced-stage solid tumors and in MASCC low-risk patients. The overall mean total cost per FN episode was $967 ± $777 with a mean LOS of 5.1 days. There was a negligible variation in cost and LOS estimates among different types of patients (by risk score group or by type of cancer). The main cost-driver was hospital stay by contrasting physician visits−a component seen to be the lowest in estimating the cost of FN.
A systematic review that examined cost of FN among patients with lymphoma reported a cost estimate of FN in the United States, Singapore, Europe, Australia, Canada, and Spain. As expected, the cost varied largely among those counties from $5,819 to $13,823 (2013, US$) . These findings appear to be different from those of this study, since the cost represents less than half of the cost found in this study. However, in all studies, the LOS in hospital was the main cost driver, which is consistent with the results of this study. The ratio of ward cost per unit among the rest of the components of total cost is important. In Colombia, the cost of hematopoietic growth factor was 11 times higher than the cost associated to hospital ward. However, in other countries, the hematopoietic growth factor was 2–3 times higher than ward cost [18, 19], and even hospital ward was higher .
Overall LOS reported in this study was lower compared to other studies, the means of which were 8 to 9 days [12, 21, 22]. However, the study showed similar tendency among the type of cancer associated with longer LOS such as leukemias, non-Hodking lymphoma and Hodking lymphoma.
Colombian studies have estimated that the direct medical costs for colorectal and breast cancer range from $ 1,556 for early-stage disease to $ 44,744 for advance-stage disease [23, 24]. Accordingly, the FN episode cost accounted for 2% of total direct costs in advance stages, and up to 67% in early stages. The vast majority of cases in Colombia are in advanced stages of the disease , and therefore, FN costs comprised a marginal proportion of the healthcare costs of overall cancer.
There were some limitations to this study. Of note: Firstly, data was limited by that available in the patient's medical history. Consequently, data related to medical services provided outside of this care setting could not be obtained. Secondly, the sample size was relatively small, since the information is only part of an institution, limited to the clinical practice of such an institution. Thus, results may not be generalizable.
This study provides accurate and conservative estimates of the costs of a FN episode. Given that the costs of procedures are calculated from the description or unique code of healthcare procedures, the information in the medical records and tariff manuals, therefore. a misclassification of neutropenia patients as FN patients could not be carried out, and the costs used are benchmarks for negotiation in the country, although they may differ from those established in some institutions.
Issues raised in this paper have provided an understanding of the factors that drive FN costs stratifying care by risk group and type of cancer. This may be the starting point to design efficient care management programs and targeted strategies related to the cost of cancer care.
Further work should be done in evaluating the indirect and intangible costs, as this may represent a substantial burden for the society and families of patients, which also contributes to the economic burden of FN episodes.
Stratifying care by risk group may be helpful in identifying alternative strategies for FN treatment that may potentially result in cost savings to the healthcare system.