Management of Fat Necrosis
Context-Specific Management Based on Etiology
Fat necrosis management depends critically on whether it occurs in the context of acute necrotizing pancreatitis versus other causes (trauma, surgery, subcutaneous fat necrosis), as pancreatic fat necrosis requires specialized multidisciplinary care while non-pancreatic fat necrosis can often be managed conservatively or with minimally invasive techniques.
Pancreatic Fat Necrosis (Acute Necrotizing Pancreatitis)
Initial Assessment and Triage
All patients with extensive necrotizing pancreatitis (>30% necrosis) require management in or referral to a specialist unit with multidisciplinary expertise including intensive care, interventional radiology, therapeutic endoscopy, and pancreaticobiliary surgery available on an emergency basis 1, 2.
Obtain dynamic CT scanning within 3-10 days of admission using non-ionic contrast to assess extent of necrosis 2.
Patients with persistent symptoms and >30% pancreatic necrosis should undergo image-guided fine needle aspiration to differentiate sterile from infected necrosis 2, 3.
The "3D" Treatment Algorithm: Delay, Drain, Debride
1. Delay Intervention
Postpone all interventions for at least 4 weeks after disease onset whenever possible, as this significantly reduces mortality by allowing better demarcation between necrotic and viable tissue 4, 2.
Sterile necrosis does not require intervention and should be managed conservatively with fluid resuscitation, early enteral nutrition (within 24 hours via nasogastric or nasojejunal tube), and monitoring for complications 2, 3.
2. Drain First (Step-Up Approach)
For infected pancreatic necrosis, percutaneous or endoscopic drainage is the mandatory first-line treatment before considering any surgical intervention 4.
Percutaneous drainage alone resolves infection in 25-60% of patients without requiring further surgery 4.
Central collections abutting the stomach should be approached with endoscopic transluminal drainage, while collections in the pancreatic tail or not communicating with the pancreas are better treated percutaneously 4.
3. Debride Only When Drainage Fails
When drainage is insufficient, proceed to minimally invasive surgical strategies including video-assisted retroperitoneal debridement (VARD) or transgastric endoscopic necrosectomy 4.
These minimally invasive approaches result in less new-onset organ failure compared to open surgery, though they may require multiple interventions 4.
Specific Management Considerations
For Biliary Pancreatitis:
Urgent therapeutic ERCP (within 24-72 hours) is mandatory for patients with concomitant cholangitis, jaundice, or dilated common bile duct 2, 3.
All patients must undergo definitive cholecystectomy during the same hospital admission or within 2-4 weeks after discharge 2, 3.
For Hypertriglyceridemia-Related Pancreatitis:
- Focus on aggressive fluid resuscitation and early enteral nutrition while managing the underlying metabolic disorder 2.
Critical Pitfalls to Avoid
Never perform early surgical intervention within the first 2 weeks, as this significantly increases mortality 4.
Do not rely solely on percutaneous drainage for definitive treatment of solid necrotic tissue, as success rates are limited (14-32%) 3.
Avoid prophylactic antibiotics, as they do not prevent infection of pancreatic necrosis; use antibiotics only when specific infections are documented 2, 3.
Do not perform emergency necrosectomy during early surgery for other indications such as abdominal compartment syndrome 4.
Non-Pancreatic Fat Necrosis (Subcutaneous, Post-Surgical, Traumatic)
Clinical Assessment
Fat necrosis should be defined as a palpable, discrete, and persistent subcutaneous firmness measuring at least 1 cm on physical examination 5.
Confirm diagnosis with imaging (ultrasound, CT, or MRI) and/or histopathologic examination when malignancy cannot be excluded 6, 5.
Treatment Algorithm Based on Size and Symptoms
Asymptomatic or Small Lesions (<1-2 cm):
- Manage conservatively with observation, as many resolve spontaneously 7.
Symptomatic Oil Cysts and Moderate-Sized Lesions:
First-line treatment is aspiration, ultrasound-assisted liposuction, or needle aeration rather than surgical excision 7.
These minimally invasive techniques avoid contour irregularities that commonly result from surgical excision 7.
Calcified or Large Areas of Fat Necrosis:
- Require surgical excision and debridement of necrotic fat tissue 7.
Special Considerations
In breast fat necrosis, recognize the mammographic spectrum ranges from lipid cysts to findings suspicious for malignancy (clustered microcalcifications, spiculated masses), often requiring biopsy to exclude cancer 8.
Fat necrosis can occur at multiple sites simultaneously without clear etiology; imaging and biopsy help differentiate from malignancy 9.
Post-surgical fat necrosis (after TRAM flaps, reduction mammoplasty, liposuction) may require staged interventions to optimize cosmetic outcomes 7, 5.