Hi dear,
I know that it is very hard for you to believe that your 44 years old sister is suffering from Gall bladder cancer. I know the pain. My beloved mom has just been diagnosed with stage IV GB cancer. She is totally asymtomatic and we found this on routine USG abdomen.
The most important for you at this time is to determine the stage of GB cancer. Ask your doctors to determine the stage of GB cancer. If you sister has few suspicious nodes, then she might have crossed stage II and might be in stage III. Up to stage II surgery can be done which will be a major surgery removing part of liver with Gallbladder and nodes around GB. The role of surgery is not there in stage III and stage IV.
If your oncosurgeon is advicing you to for the surgery, if the rumor is fairly localized then you should go ahead with it. For Gb cancer, surgery is the only way to treat the cancer and remove the GB. GB cancer is very aggressive and without surgery/chemo, it will spread in couple of months.
On the other hand your sister might not be suitable candidate for chemo because as you said, she is very weak. Gemcitabin with cisplatin is standard regimen for advanced GB cancer. Gemcitabin is relatively safer drug compared to some other chemo drugs. no hair loss with Gemcitabin, very few nause and vomitting which can be controlled with prior medication, very few drop in WBC count which comes back to normal once the drug is stopped.
So ask your doctor about the benefit vs adverse effect of surgery as well as chemo. Because without doing anything GB cancer will spread lightening fast.
Good luck adn will pray for your sister.