As the good old Wiki article points out, neither of these DIRECTLY
infectious cancers are Human.

I thought that, in general Cancers were regarded as a good example of MULTIPLE CAUSALITY, in that most have no single attributal cause, but many assosciations apparent from statistical evidence.

There are comparitively recent examples where single cases of overwhelming evidence emerges from statistical evidence. Smoking and lung cancer? Strong evidence that smoking leads to lung cancer, but not all smokers get lung cancer, and some non smokers do.

Similarly Cervical Cancer - strongly assosciated with HPV - but not all HPV sufferers get Cervical Cancer, and some people get Cervical Cancer without HPV.

I do not think we have ANY human cancer with a direct and exclusive cause, let alone an infectious one.

Again, not everyone who gets infectious Hepatitis goes on to get Liver cancer - in fact MOST don't. Others get Liver Cancer with no sign of infectious Liver disease. Infectious means that something is passed from one person to another, i.e. one person catches Liver or Cervical Cancer from another - this does not happen.

Again in the Liver case, Disease is only one of a number of trigger factors which include Alcohol/drug/chemical damage. The liver has to deal with the removal of all toxins we take in and therefore has to put up with a lot in the average lifetime.

It is well worth getting vaccinated against Hepatitis A and B and HPV in their own right, and as contributary factors in the cancer story. Sensible Alcohol consumption is also a good idea, since alcohol abuse is a major factor in Liver Cirrosis, often leading to Cancer.

Hepatitis B carriers number between 3 and 6% of the global population, with as many as 1 in 3 exposed in some countries. It does kill in its own right. Most healthy people recover completely, eliminate the virus and become immune for life. Excepting blood transfusion, they are non infectious. A small number descend into a long term cronicity, with slow liver damage occuring, with infectivity. Some remain asymptomatic, but permanently infectious. Many countries have started vaccination programs and others offer it on demand.

"a growing and highly respected community of researchers
in cancer and infectious diseases believes that
microorganisms-viruses, bacteria, and parasites-play a
significant role in cancer, heart disease, diabetes, and other
illnesses that are not traditionally regarded as infectious. "

Full article

Gee, look at the list of oncoviruses and cancer bacteria...OK, some can be sexually transmitted...but hey, some you can get from a kiss!

F word would be in order here!