Recent advances in cancer treatment and a better insight into the molecular pathways regulating tumorigenesis and metastasis have dramatically enhanced overall survival rates of several childhood cancers with consequent greater life expectancy. Therefore, there is an increasing number of pediatric patients formerly treated for cancers [1]. The acute and chronic consequences of cancer, caused not only by the cancer itself but also by the treatment methods employed, are impacting the life of many children. Cancers can trigger an immune response that could damage various components of the organ systems not primarily involved by the cancer. Radiation therapy (RT), chemotherapy, hematopoietic stem-cell transplantation (HSCT), and surgery are the mainstays of treatment of pediatric solid tumors as well as hemato-lymphoid malignancies. All of these treatment methods can instigate acute life-threatening complications, as well as the late consequences like chronic organ dysfunction or secondary cancers. Even though there have been advancements in decreasing toxicity from cancer therapy, several complications stay unavoidable [2]. Additionally, the evolution of new treatment regimes inevitably leads to the development of novel complications. According to present estimations, greater than 75% childhood cancer survivors will suffer nonetheless 1 late effect post treatment [3]. Early detection of treatment-related complications (TRCs) and their management have become pivotal for better patient outcomes. TRCs can be early or late. Early complications present during treatment or arise in a few months after treatment, whereas late complications usually take months to years to develop after treatment and could cause long-lasting morbidity [4]. Understanding of these potential after-effects makes the clinicians more vigilant for the signs and symptoms guiding the further management of pediatric cancer patients. Early in the treatment course (i.e., within 1 year), the complications are usually due to infections or treatment toxicity, whether chemotherapy-related or toxic effects resulting from radiation therapy. Secondary cancers that develop due to treatment complications most often involve the bone marrow, brain, thyroid, and breast [4, 5].