Nial Wheate, Senior Lecturer in Pharmaceutical Chemistry at University of Sydney provides a quick but very useful guide that we can use to assess whether proposed treatments are likely to do us any good:
I'm fairly certain that we've all been recommended different supplements by well meaning friends that want us to overcome this incurable cancer. Unfortunately, just because they know someone who was helped by what they are recommending, as the article says "anecdotes are not evidence". Blood cancers are fairly rare and it is unlikely you'll be suggested something that helped someone with blood cancer. Our cancerous lymphocytes can be found all throughout our body, including fairly inaccessible places to even traditional chemotherapy drugs - i.e. our bone marrow. Also CLL is just one of many blood cancers; there are many lymphocyte blood cancers too and drugs that work well on other B-lymphocyte cancers don't necessarily work well on CLL or SLL. Finally we know from clinical trials that even CLL specific drugs don't work well on every CLL patient - it depends on the specific genetic damage your CLL cells actually have. So it's a pretty small likelihood that substance X is going to do you any good. By all means thank your friend and say you'll check it out. This article gives you the tips you need to assess those well meaning suggestions so that you can report back that you did investigate your friend's suggestion and tell them what you found.