The lymphatic and immune system consists of lymphatic vessels, lymph nodes, spleen, thymus gland and tonsils that collect excess fluid, transport substances around the body, and serve as the primary defense against pathogens. Hodgkin's disease is a type of lymphoma originating in lymphocytes that is characterized by orderly spread between lymph node groups and associated symptoms. It is treated with radiation and chemotherapy depending on factors like age and sex, and has a high survival rate if detected early. Kaposi's sarcoma is a tumor caused by the human herpes virus 8 that presents as lesions on the skin and other areas, and its transmission can be prevented through safe sexual practices and screening of organs before transplantation.