I think 4 is a much larger issue. Cancer is hard, and low hanging fruit is easier to find.
Also, adding 4 months of life when you're talking about something 40% of Americans are going to be diagnosed with really is a huge deal. Adding say 1 extra day of life to every cancer patient in the US would be the equivalent of saving ~25 lives each and every year.
It's hard to talk about in aggregate because chemotherapy doesn't have the same effect on all types of cancers.
I went through it. Aside from whatever months it added, it took about 3 of them away because I wasn't doing anything other than barfing, chugging hydrocodone syrup, and sleeping for that time period.
I should also add that I clearly wasn't getting the worst of it. Breast cancer patients seemed to have 6+ months vs my 3+ months for my adenocarcinoma. Also, I didn't lose my hair, finger nails, etc. It was, though, 3+ months lost to nausea, hydrocodone fog, pain, and sleep.
Also, adding 4 months of life when you're talking about something 40% of Americans are going to be diagnosed with really is a huge deal. Adding say 1 extra day of life to every cancer patient in the US would be the equivalent of saving ~25 lives each and every year.