Diagnostics plays an essential role throughout cancer cure. Before treatment, to accurately diagnose Tumors, stage the illness, and regulate an appropriate combination of cancer diagnosis. Diagnostics are used to trail the size of the tumor, evolution of the disease, and patient response to treatment, and revise your treatment accordingly. To verify the diagnosis of most cancers, a liquid Biopsy needs is to be done in which a tissue sample is removed from the tumor which results initially and examined under a microscope for detecting tumor cells. Endoscopy is done by implanting a flexible plastic tube with a minute camera into body cavities or organs. Cancer Screening tests are used to identify the possibility of tumor cells which is present before symptoms result. To detect cancer at its initial stage, various types of diagnostic tests are used to Screen at-risk individuals, Monitor treatment efficacy and illness progression or recurrence, Predict prognosis and control treatment, Monitor an asymptomatic population for the early detection of cancer and treatment therefore drops cancer fatality, analyze a primary cancer and recognize the cancer subtype after whole cancer treatment, to feature for any signs of metastasis or recurrence.