Medical oncology is the branch of oncology dealing with administration of chemotherapeutic drugs to achieve cure/control of malignant diseases. While surgery and radiotherapy are modalities that deal with locoregional disease, chemotherapy addresses metastatic disease (gross/microscopic) and to some extent the locoregional disease with varying efficacy depending upon the chemosensitivity of the tumor. Presently metastatic disease is mostly treated with palliative intent with the aim of prolongation of life and palliation of symptoms with few exceptions like testicular cancer, osteogenic sarcoma, pediatric tumors and lymphomas. Presently combined modality treatment viz. Surgery + chemotherapy + radiotherapy are commonly used for majority of cancers.