Rising CA19-9 in Lung Cancer patient

Dear Doctor,

My mother is a small Asian woman, 60 years old, and in 2009 she has been diagnosed of non-small cell lung cancer at stage III-IV. There has been metastasis to the lymph node and the brain. Over the past 4 years she has received a number (of different recipes) of systemic chemotherapy, radiation, whole brain radiation, and gamma-knife at a research center in Kobe (IBRI), and she has gotten rid of most the tumors (apart from a small tumor in her brain and in her lungs that is left, but is presumed inactive by her oncologist because it hasn't been growing). On the side she also has tried a number of alternative treatments such as Immunotherapy, traditional Chinese medicines, and others.

I actually have a simple question... because all of a sudden her recent CA19-9 reading has increased from around 180-200 U/mL to 379 U/mL and that has gotten our family very worried. Though her CA125 has decreased from 115 to 98.5 U/mL, and her CEA is at 3.29 U/mL. She also recently loss the strength to walk on her own, her weight is currently 40Kg, but she was never heavy, she weighted 49Kg at her best health. Everything at this point seems to indicate that she has been weakened by the treatments that she has received over the past four years. But it doesn't seem like she can stop any time soon because if we do, then the cancer might grow again. But now she is becoming too weak ...

She has trouble sleeping at night because of frequent urination (almost every hour)... Is there anything we can do about that? Another note is, she also recently requires the use of an oxygen machine occasionally when she exerts too much force, talk too much, etc, she gets tired and couldn't breathe as well.

I would very much appreciate any thoughts, tips, and advice on how to go about beating this disease, we never lost hope, not since the very first month she was diagnosed and her first doctor said she only had 6 months left...

Thank you so so much,
Natasha