I had a chance to attend a webinar by an immunologist who has been working on immuno-oncology for bladder cancer, so I asked your question to her. She also told me that the best source of the information is your doctor/urologist. She also said a pharmacist can be a good source of the information. Anyway, below is her answer to your question.
In terms of how NSAIDs might affect the BCG-induced anti-tumor immune responses, I think the worry stems from the fact that an inflammatory response to BCG is an important part of its anti-tumor effect. COX enzymes can contribute to inflammation (including the pain associated with inflammation) by producing things called prostaglandins. Inhibiting the COX enzymes reduces the pain caused by these prostaglandins, but it can also reduce their other inflammatory effects. That being said, there are many things that contribute to immune activation in response to BCG, and so blocking prostaglandins is not necessarily going to prevent this immune activation. Also, when you take an NSAID you are not completely getting rid of all prostaglandins, you are just decreasing them for a short period of time, so you are not preventing all their inflammatory effects.
Another important thing to remember is that there is not only one type of immune response, and certain kinds of inflammation and immune responses can actually help tumors grow. Certain types of prostaglandins have been found to support a pro-tumor immune response and so scientists are actually looking into COX inhibitors as potential anti-cancer drugs. I am not saying you should start taking NSAIDs to treat cancer, the point I want to make is that the biology involved in the interaction between cancer and the immune system is really complex, and our understanding of it is incomplete. So even when things seem to make sense (i.e. inflammation is involved in BCG efficacy and NSAIDs can decreased inflammation, so it might make sense that NSAIDs would limit BCG efficacy) they often do not turn out to work that way.
At the end of the day what matters is the outcome in the clinic, and as far as I know, they have not seen reduced efficacy of BCG when people take ibuprofen for pain. Your doctor can advise you on the best ways to manage the side effects of BCG, including when taking an NSAID would be appropriate/advisable. She also suggested that pharmacists can be also a good source of information.
I have found that the Canadian Urological Association published Guidelines for NMBIC recommends NSAIDS in addition to UTI specific pain drug. Table 1 / page E698.
Below recent study indicates the use of NSAIDs does not affect the efficacy of BCG treatment.
Because Ibuprofen is non-specific COX enzyme inhibitor, I will be careful of other side effects of the drug.
A case in point, 15 years ago, my brother who had chronic asthma died from taking aspirin to relieve his headache. I was not there myself but his wife told me that after taking aspirin he looked like he was choking. Though he was taken to a hospital by ambulance. He has soon announced brain death. Back then, neither my brother and I did not know that COX enzymes relax airways in the lungs. Aspirin inhibits COX enzymes, thus constricting the already constricted airways of asthmatic patients. So, I believe that patients should learn as much as possible about their diseases and treatments.
Has anyone heard that you shouldn't take ibuprofen when undergoing BCG treatment "since it is an inflammatory and you want inflammation"? I read it somewhere (perhaps I'm reading too much about all of this!) and wondered what others were told. thank you for your input
8/20 tumor found, 2 TURB with stent, tumor resected from bladder, another portion lasered from ureter, Toa,papillary urothelial carcinoma, non-invasive, high grade, BCG began Oct 22,2020