The course of cancer development has been presented in this book beginning from normal cells to cancerous form and the genomic instability, the cancer treatment as well as its prevention in the form of the invention of a vaccine. Certain diseases are also elucidated, like leukaemia, glioma, breast cancer, and cervical cancer. Comprehending cancer through its molecular mechanism is required to decrease the cancer incidence. Complications like metastasis and drug resistance and the procedure of treating cancer more efficiently are vividly illuminated in this book along with some research results that could be employed to treat the cancer patients in the not too distant future. The book encompasses topics like HER2 carcinogenesis: treatment, etiology & prevention; DNA repair mechanism & cancer; new approach to cancer mechanism and novel role of oncogenes & tumor suppressor genes.