Kaposi's sarcoma is primarily a cancer of which body part?

Kaposi's sarcoma is primarily a cancer that affects the skin. This type of cancer is characterized by the formation of purple, red, or brown patches on the skin, which occur due to abnormal blood vessel formation. It is most closely associated with immunocompromised states, such as in patients with HIV/AIDS.

While Kaposi's sarcoma can spread to other parts of the body, including the lymph nodes and internal organs, its most commonly recognized manifestation is through skin lesions. This visibility on the skin makes it a distinct cancer, leading to its identification primarily as a skin cancer in medical literature. The other options represent different types of cancers that do not specifically correlate with Kaposi's sarcoma.