**Abstract**

Immunosuppressants offer some benefits and disadvantages. Like a blade with two edges, immunosuppressants are categorized as drugs but also cause decreased immunity, which eventually cause cancer. Immunosuppressants are widely used in organ transplantation patients and autoimmune illnesses to suppress the immune response and provide a significant risk of cancer. According to epidemiological and cancer research, malignancies are higher among transplant patients. However, the risk varies significantly between studies due to methods and patient selection variations. A more accurate illustration of the effects of mild-to-moderate immunosuppression concerning the risk of cancer can be seen in the rising use of immunosuppressant medications in non-transplant patients. Generally, cancer cells have an approach to avoid immune surveillance and create a complex balance in which many immune subtypes may be responsible for controlling tumor development, metastasis, and resistance. Therefore, the main objective of most cancer immunotherapies is to reestablish effective immune control. Immunomodulators help to maintain immune system function and promote the immune system's capacity to fight and defeat cancer. One of them is immune checkpoint inhibitors.

**Keywords:** immune system, immunosuppressant, immunomodulator, immune checkpoint inhibitor, cancer
