WordNet records no synonym and no antonym for kaposi's sarcoma. It is the only member of its synset, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a sarcoma that starts with purplish spots on the feet and legs and spreads from the skin to lymph nodes and internal organs; a common manifestation of AIDS
“until 1980 Kaposi's sarcoma occurred almost exclusively with Jewish or Italian or black men”
Synonyms, antonyms and the broader and narrower relations for kaposi's sarcoma come from Princeton University’s WordNet. Full sources and licences.