Cancer. Many types of cancer can be found, like, lung cancer, breast cancer, prostate cancer, skin cancer, stomach cancer, colorectal cancer etc. So I believe Cancer would be the best answer
Cancer is a disorder that can occur in multiple organ systems. A cell becomes cancerous when that cell divides and grows uncontrollably. A cancerous cell shows metastasis which means it can move from its original place and can invade other tissues and organs.
This metastasis property allows a cancer cell to form secondary malignant growth and form cancer in multiple organ systems. Cancer can affect many organs that is why there are several types of cancer like lung cancer, blood cancer, mouth cancer, etc.
