Four medicinal cancer biological blockbusters will end their patent lifespan by 2020. It is estimated that the total market for cancer biologicals will reach approximately US$68 billion at that time. Approximately 20 biosimilars have entered the European market since the launch of the original approval guidelines in 2005, and four biosimilars have been approved in the USA since 2015. Data from European countries with the highest market entrance of biosimilars suggest that the incorporation of biosimilars into healthcare systems worldwide may result in a 30-45% cost savings. Initial levels of apprehension expressed by healthcare providers regarding the safety and efficacy of integrating biosimilars into the treatment of cancer patients have gradually decreased through active educational programs. The trust generated by regulatory agencies and drug manufacturers will ultimately make the adoption of biosimilars by healthcare providers and patients a smooth process. Future efforts to improve on the global acceptance and safety of biosimilars must include standardization of naming, regulatory requirements, and pharmacovigilance programs worldwide. High expectations are being placed on the cost savings, safety, and efficacy of these products. The entry costs for biosimilars and the pricing reaction of their originator products will determine the true savings by troubled health systems in dire need of cost cuts. This article discusses basic principles of biosimilars in hematology and oncology, the current status of their clinical development, and trends of acceptance by healthcare providers, and provides insight into potential future challenges.