Immunotherapy

I lost my husband 2 weeks ago after an 11 week fight with SCLC. He was 56 years old, fit and healthy before this. He was given platinum chemo and immunotherapy. He took the 1st cycle in his stride with barely any symptoms which seemed strange at the time. He was playing golf 4 days afterwards. After the 2nd cycle, he got really hit, with fatigue etc, he did not pick up after the 3rd week and ended up in hospital with inflamed lymph nodes etc which filled with fluid which pressed on his Superior vena cava. His cancer was chemo resistant as well. A massive dose of steriods had little effect - he never got the 'manic' phase or energy boost nor raging appetite. Just a little reduction in the swelling. He then filled with fluid, swelled up everywhere and was dead within 4 weeks. I am struggling to come to terms with this as I feel he was not monitored enough and the doctors just sent him home to die, saying 'oh well you should have 3 months together, go and enjoy life'. We never got that just a horrific time of me nursing him at home, whilst he fought extreme fatigue, breathlessness etc. I feel like the chance of imuunotherapy not working and shortening his life was never discussed with us during his initial consultation. I suppose hindsight is a great thing but if we had known we would not have started treatment and then at least he would have had some quality of life for a couple of months before this terrible disease took him. Why can't they test at the beginning to see if the type of cancer he had would respond to chemo or immunotherapy instead of just taking a risk to 'see if it worked', I feel like they treated him worse than a lab rat because at least they are monitored etc. Just seems like treatment has not moved on very much in the last 50 years. My husband was an amazing big, beautiful, kind, funny, generous man.