An early diagnosis of gallbladder cancer is difficult since the early stages of the cancer go unnoticed due to the lack of specific signs or symptoms. The clinical features produced by gallbladder are mimicked by a number of other conditions. Early symptoms mime gallbladder inflammation due to gallstones. The later symptoms are similar to those produced by biliary and stomach obstruction.
The cancer may be an incidental finding when the gallbladder is removed for other reasons or if an ultrasound may show a mass in the gall-bladder.
Diagnosis begins with physical examination and elicitation of history. Signs of the disease, such as lumps are searched for.
Once suspected an ultrasound examination of the abdomen helps in diagnosis gallbladder cancer. Other Imaging techniques employed include:

CT scan

MRI scan

ERCP (endoscopic retrograde cholangiopancreatography): This aids in visualising the duct system that carry bile

Chest X-ray

PTC: Percutaneous transhepatic cholangiography is used to x-ray the liver and bile ducts

Laparoscopy aids in direct visualisation of organs

Blood tests-
Liver function tests are performed to know if the liver has been affected due to gallbladder cancer.

Levels of
Carcinoembryonic Antigen (CEA) are checked for. CEA is a protein produced by both cancer cells and normal cells. Higher levels of CEA may indicate gallbladder cancer or other conditions.

Another similar test is
CA 19-9 assay. CEA and CA 19-9 are referred to as ‘tumour markers’.