cancer of the blood vs leukemia

cancer of the blood and leukemia both are nouns.

Word	Noun	Adjective	Verb	Adverb
cancer of the blood	Yes	No	No	No
leukemia	Yes	No	No	No

As nouns, cancer of the blood and leukemia are synonyms defined as:

cancer of the blood and leukemia: malignant neoplasm of blood-forming tissues; characterized by abnormal proliferation of leukocytes; one of the four major types of cancer

Other synonyms of cancer of the blood include leucaemia, leukaemia.

cancer of the blood (noun)	leukemia (noun)
malignant neoplasm of blood-forming tissues; characterized by abnormal proliferation of leukocytes; one of the four major types of cancer	malignant neoplasm of blood-forming tissues; characterized by abnormal proliferation of leukocytes; one of the four major types of cancer