Definition: Macrotyloma is a type of tumor that starts in the cells lining the blood vessels, usually in the arteries or veins. It's characterized by abnormal growths called microtubules, which can grow uncontrollably and disrupt normal cell function. This condition can be caused by genetic mutations, but it also involves environmental factors such as exposure to certain chemicals or toxins. Macrotyloma can lead to serious health issues if not properly managed.