The answer to the question "what is the worst type of cancer?" is not straightforward, as different sources provide different answers based on various criteria. Here are some of the deadliest cancers based on different sources:

• Lung and bronchus cancer: According to multiple sources, including the American Cancer Society and the Centers for Disease Control and Prevention, lung and bronchus cancer is responsible for the most cancer deaths in both men and women in the United States. This cancer is often caused by smoking and tobacco products, and it is difficult to treat, especially in advanced stages.

• Pancreatic cancer: Pancreatic cancer is also considered one of the deadliest cancers, with a low survival rate and a high mortality rate. It is often diagnosed at an advanced stage, and it is difficult to treat due to its location and aggressive nature.

• Liver and intrahepatic bile duct cancer: This type of cancer is also among the deadliest, especially in men. It is often caused by chronic liver disease, such as cirrhosis, and it is difficult to treat due to its location and the lack of effective therapies.

• Esophageal cancer: Esophageal cancer is another deadly cancer that is often diagnosed at an advanced stage and has a low survival rate. It is more common in men than women, and it is often caused by chronic acid reflux and Barretts esophagus.

• Colorectal cancer: Colorectal cancer is one of the most common cancers, and it is also among the deadliest. It is often preventable through screening and early detection, but it can be difficult to treat in advanced stages.

It is important to note that cancer is a complex disease, and the severity and prognosis of each type of cancer depend on various factors, such as the stage at diagnosis, the location of the cancer, the patients age and overall health, and the available treatments. Therefore, it is crucial to consult with a healthcare professional for personalized information and advice.