Survival benefits of patients with a malignant tumor have been improved significantly over the years, partially attributed to the employment of novel anti-cancer therapies. Recent success in immunotherapy propels cancer treatment to an exciting new era after traditional chemotherapy and targeted therapy. To date, approximately 4000 clinical trials focusing on programmed cell death protein-1/programmed cell death protein ligand-1 (PD-1/PD-L1) inhibitors have been carried out in at least 20 types of cancer, including both solid and hematological tumors; the total number of subjects worldwide is more than 20,000. For the moment, approximately six PD-1/PD-L1 inhibitors are commonly used in clinical practice: Nivolumab, Pembrolizumab, Atezolizumab, Avelumab, Durvalumab, and Cemiplimab. These PD-1/PD-L1 inhibitors are demonstrated to have the preeminent potential for long-term survival, but along with dramatic high drug costs. Although the rapid development of novel therapies has provided insights into the future direction of treatments for malignancy, the high cost of cancer treatment has become a major concern for patients and the society. The financial toxicity may lead to psychosocial distress, poor quality of life (QOL), and worse patient outcomes. Thus, the focus that if the survival benefit and living quality are in proportion to the economics expenditure has been in the spotlight...