cervical cancer

hello i am new to this, but my mother has the re occurance of cervical cancer. About a year ago she was told that the cervical cancer was back with a big lymph node just below the rib cage. She has gone through a entire year of chemo and radiation and her tumor marks have gone down to where her last treatment was last month meaning what we thought she was cancer free. Now come to find out she has been retaining fluid and her oncologist had sent the fluid to pathology and came back negative for cancer tumors. Her tumor marks has gone up to 141. Still no signs of cancer but retaining fluid. doctors do think that she could have liver disease. Also a PET Scan was done about a week ago also no signs of cancer but really can't tell because her doctor says its hard to tell with fluid in her body. She is already on diuretics. Does anyone or has anyone gone through this before. my brother and i have been doing some non stop research and we could use some help. Thanks