Hi, Thanks for writing in. Chemotherapy is known to raise cholesterol and triglyceride levels in many people like your mother in law. Medical literature demonstrates increased receptor-mediated uptake of low density lipoprotein (LDL) in many types of malignant cells compared with normal cells. The person undergoing chemothrapy will not get fate. Increase in choestero does not mean becoming fat. It refers to the increased concentration of chlesterol in the blood with trilycerides. This pattern is seen as a result of change due to increased absorption of fats and also metablic changes leading to high circulating levels of these components. It also means that the patient might have incrased risk to cardiovascular disease. Regular follow up is required. Please do not worry.