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Introduction
The treatment of cancer often requires chemotherapy (CT). Adjuvant chemotherapy (ACT) is often prescribed after surgery and required to eradicate residual tumour cells. The appropriate doses and regimens of CT depend on the type of cancer, stage, performance status of patient, and several other factors. The dose intensity is known to be critically important to increase the disease-free and overall survival in patients with potentially curable tumours, such as diffuse B-cell lymphoma or germ cell tumours. However, for ACT used in early breast cancer, colorectal cancer, non-small cell lung cancer (NSCLC) and pancreatic tumours, the decision to commence cytotoxic therapy is not an easy one since, for some patients, ACT may be unnecessary and accompanied by significant, even fatal adverse effects (1).
Despite the use of guideline recommended doses, in real clinical practice, the rate of patients with serious manifestations of treatment-associated toxicity can be significantly higher compared to the data published in randomised trials. For example, in a retrospective study by Lakhanpal (2) (real practice) the febrile neutropenia rate in patients with breast cancer, who had received docetaxel/cyclophosphamide ACT, accounted for 25% of cases. Likewise, the Jones et al (3) clinical trial showed that only 2.4% of patients had this severe adverse event. Poor tolerability of anticancer drugs often requires dose decrease or treatment discontinuation. A study of oxaliplatin in patients with colorectal cancer showed that the rate of patients who discontinued participation early in the study rose up to 31%, and the rate of those who required dose reduction accounted for 62% of cases (4,5). Reduction of doses and even treatment cessation may be caused by several undesirable effects: Haematological toxicity, hepatic toxicity, renal toxicity, severe mucositis, poor nutritional status, progressive weakness. Therapy toxicity and side effects are associated with poor quality of life (QoL) that in turn may negatively affect patients' mood, appetite, compliance and decision-making regarding CT continuation (6).
To maintain QoL and effective CT dosages, the use of all available supportive therapy options needs to be explored. In this regard, the development of new approaches to maintain QoL and comply with recommended CT regimens is an important task to increase the survival of patients with ACT.
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