GI junction cancer with liver mets.

My dad is suffering from GI junction cancer with liver Mets from Feb 2016. Doctor advised for palliative chemotherapy of 6 cycles. Her2neu is negative. Had 3 cycle of chemotherapy where his numbers and size of tumours reduced by 30 percent. Then after 2 more cycles it reduced by more 50 percent. He couldn't able to take 6th cycle due to sepsis. Due to chemo side effects his sodium potassium and magnesium levels dipped. But it got controlled. After 5 cycles report was showing that he was responding good. But there was pleural effusion and ascites. Which was drained out and protein and albumin infusion are given. Then in the month of December disease again increased by 33 percent. Again dctr advised for chemo. After 3 cycles it reduced slightly but pleural effusion and ascites are seen. Again after 3 cycle secondary cancer increased. Pleural effusion increased. Ascites increased. My question how after chemo cancer is increasing? What are the chances of survival here.