What is the appropriate evaluation and management approach for a patient presenting with a gallbladder lump, potentially indicating gallbladder cancer or other serious conditions?

Evaluation and Management of Gallbladder Lump

For a patient presenting with a gallbladder lump, immediately obtain transabdominal ultrasound with liver function tests, followed by high-quality cross-sectional imaging (CT or MRI/MRCP) to evaluate for gallbladder cancer, as this is a rare but lethal malignancy that requires urgent surgical evaluation if resectable. 1, 2

Initial Diagnostic Workup

Laboratory Assessment:

• Complete blood count and liver function tests to assess hepatic reserve 1, 2
• Tumor markers CEA and CA 19-9, though these are not specific for gallbladder cancer and can be elevated in biliary obstruction, inflammatory bowel disease, and other malignancies 2, 3
• If jaundice is present, obtain these markers before any biliary intervention 4

First-Line Imaging:

• Transabdominal ultrasound is the initial investigation of choice 1, 3
• Look specifically for: sessile versus pedunculated morphology, size >10mm, focal wall thickening ≥4mm adjacent to the lesion, and signs of invasion (liver involvement, vascular compression, lymphadenopathy) 2

Advanced Imaging Protocol

High-Quality Cross-Sectional Imaging is Mandatory:

• MRI with MRCP is the optimal modality, providing information on gallbladder wall penetration, direct tumor invasion of adjacent organs, major vascular involvement, nodal metastases, and extent of biliary involvement 2, 1
• Contrast-enhanced CT is acceptable if MRI unavailable, particularly spiral/helical CT for suspected vascular involvement 2, 4
• Chest imaging to exclude distant metastases 2, 4

Additional Cholangiography if Jaundice Present:

• MRCP is preferred over ERCP or PTC unless therapeutic intervention is planned 2, 4
• This evaluates hepatic and biliary invasion by tumor 2, 4

Distinguishing Benign from Malignant Lesions

High-Risk Features Suggesting Malignancy:

• Size >15mm (neoplastic polyps average 18-21mm versus 4-7.5mm for benign) 2
• Sessile morphology rather than pedunculated 2
• Focal wall thickening ≥4mm adjacent to polyp 2
• Age >50 years, presence of gallstones, or porcelain gallbladder 2, 5

If Differentiation from Tumefactive Sludge is Challenging:

• Short-interval follow-up ultrasound in 1-2 months with optimized technique and patient preparation 2
• Contrast-enhanced ultrasound (CEUS) if available—sludge will not enhance, whereas vascular masses will show enhancement 2
• MRI with post-gadolinium sequences as alternative to CEUS 2

Surgical Decision-Making

Staging Laparoscopy:

• Perform laparoscopy in conjunction with surgery if no distant metastasis found on imaging, to identify occult peritoneal or liver metastases 2, 4

Surgical Approach Based on Suspicion:

• If gallbladder cancer is suspected preoperatively, do not perform laparoscopic cholecystectomy 5
• For confirmed or highly suspected malignancy: radical cholecystectomy with hepatic resection (segments IVb/V) and lymphadenectomy of hepatoduodenal ligament 4, 6
• Only 10-30% of patients are candidates for curative resection at diagnosis 5, 7

Incidental Finding After Simple Cholecystectomy:

• If pathology reveals T1b or greater tumor, patient requires re-evaluation and radical surgery 2, 5, 6
• Port-site excision is necessary if initial removal was laparoscopic 5

Management of Unresectable Disease

Systemic Therapy:

• First-line chemotherapy with cisplatin-gemcitabine-durvalumab for unresectable disease 4
• Adjuvant capecitabine (eight 3-weekly cycles) after R0 resection improves median overall survival from 36 to 53 months 4

Palliative Biliary Drainage:

• Metal stents preferred over plastic stents if estimated survival exceeds 6 months 4

Critical Pitfalls to Avoid

• Do not rely on imaging alone—tissue confirmation is mandatory before initiating non-surgical oncological therapy 3
• Do not request FISH testing for gallbladder masses, as this test is only validated for biliary strictures and cholangiocarcinoma, not gallbladder cancer 3
• Do not delay surgical evaluation in lesions >10mm with high-risk features, as gallbladder cancer is often diagnosed late with overall 5-year survival <5% 5, 7
• Do not miss the diagnosis—47% of gallbladder cancers are discovered incidentally after cholecystectomy for presumed benign disease, emphasizing the need for routine pathological examination of all cholecystectomy specimens 3, 6
• Recognize that clinical presentation mimics benign disease—sudden change in symptoms in a patient with known gallstones should raise suspicion for malignancy 5, 8