What is the treatment for adenomyomatosis of the gallbladder?

Treatment of Adenomyomatosis of the Gallbladder

Cholecystectomy is the definitive treatment for symptomatic adenomyomatosis of the gallbladder, while asymptomatic cases can be managed conservatively with observation except for segmental and diffuse types which may warrant surgical intervention due to increased malignancy risk. 1, 2

Understanding Adenomyomatosis

Adenomyomatosis (AMM) is a benign, acquired condition characterized by:

• Excessive epithelial proliferation with hypertrophy of the muscularis propria 1
• Formation of Rokitansky-Aschoff sinuses (outpouchings of mucosa into or beyond the muscle layer) 1
• Three recognized types: fundal, segmental, and diffuse 1
• Prevalence in cholecystectomy specimens between 1-9%, with incidence increasing after age 50 2
• Equal sex distribution in general, though some studies report female predominance (ratio 1:3.7) 2, 3

Diagnostic Approach

Diagnosis is primarily based on imaging findings:

• Ultrasound (US): First-line imaging showing thickened gallbladder wall with intramural cysts, "comet-tail" artifacts, and "twinkling" artifacts 1, 2
• MRI with cholangiography sequences: Reference examination demonstrating characteristic "pearl necklace" sign 1, 2
• CT scan: May show "rosary sign" but has lower diagnostic accuracy than MRI 1, 4
• Contrast-enhanced ultrasound (CEUS): Can help differentiate adenomyomatosis from other gallbladder lesions 4

Treatment Algorithm

1. For Symptomatic Adenomyomatosis (any type):

• Cholecystectomy is indicated - provides complete resolution of symptoms 2, 5
• Laparoscopic approach is preferred when feasible 4
• Surgery should be performed by experienced surgeons to minimize complications 4

2. For Asymptomatic Adenomyomatosis:

Fundal type:

• Observation with ultrasound follow-up is appropriate 1
• No consensus on frequency or duration of surveillance 1

Segmental type:

• Consider cholecystectomy due to increased risk of malignancy 1, 6
• Studies show segmental type is associated with more advanced gallbladder cancer when malignancy develops 6

Diffuse type:

• Consider cholecystectomy due to difficulty in visualizing any coexisting malignancy 1
• Diffuse wall thickening may obscure early malignant changes 1

3. Special Considerations:

• When diagnostic uncertainty exists: Cholecystectomy is justified to avoid overlooking malignancy 1, 2
• When adenomyomatosis is combined with gallstones (occurs in 59-90% of cases): Cholecystectomy is generally recommended 3, 2
• When adenomyomatosis is combined with polyps: Cholecystectomy should be considered due to potential malignant transformation 3, 5

Surgical Approach

• Open or laparoscopic cholecystectomy are both appropriate options 4
• Laparoscopic cholecystectomy offers reduced recovery time but requires appropriate surgical expertise 4
• The potential risk of bile duct injury should be considered, especially with laparoscopic approach 4

Post-Treatment Follow-up

• No special surveillance is required after complete removal of adenomyomatosis 2
• The discovery of adenomyomatosis in a cholecystectomy specimen does not necessitate additional follow-up 2

Important Caveats

• Adenomyomatosis has historically not been considered premalignant, but recent studies suggest segmental type may have increased malignancy risk 6
• Diagnostic accuracy is crucial - if there is any doubt about malignancy, surgical intervention is warranted 1, 2
• Adenomyomatosis is often associated with other gallbladder conditions including cholesterosis (56.7% of cases) and lipomatosis (64.9% of cases) 3
• The presence of adenomyomatosis may prevent early detection of gallbladder cancer, which is why some experts consider preventive cholecystectomy in asymptomatic cases 6