ALK+ Overall Survival prospects - 1293683

I was diagnosed with stage IV adenocarcinoma in Sept 2017. I’ve successfully had radiation for lung tumor and spine tumor reduction. I’ve completed two cycles of chemo (carbo/peme/avastin) before learning I was ALK+. The chemo + radiation reduced my lung tumor by ~65% and the lymph nodes and spine tumors are stabilized. I’m now on Alectinib since mid Dec 2017. I’ve been doing a lot of research on my survival prospects on ALK+ mutation but most of the data is old (some Canadian study had data that was dated). Given the advancement of the new TKIs I’m looking for something more recent. I know most people go through 3+ TKIs before they’ve exhausted targeted treatment and then jump to chemo or I’ve even heard of some trying immunotherapy in the final stages. With the lack of recent overall survival data should I just add the median PFS numbers for 3 TKIs (e.g. 25.7 mos for Alectinib + 12.9 mos for brigatinib + 7.7 for Crizotinib) and then make an assumption for chemo after the TKIs wear off? I know people don’t like to talk about this because it involves your own mortality but it gives me a baseline to try and beat.