Management of Lipomas
For most lipomas, observation without intervention is the recommended management approach unless they become symptomatic, rapidly enlarging, or have concerning features.
Diagnostic Approach
- Lipomas are adipose tumors that typically present as nonpainful, round, mobile masses with a characteristic soft, doughy feel, usually appearing between 40-60 years of age 1
- Ultrasound is an effective initial diagnostic tool to confirm the lipomatous nature of masses, particularly in patients with a history of similar growths 2
- MRI with expert review should be performed if there is diagnostic uncertainty, as it can differentiate between benign lipomas and atypical lipomatous tumors (ALT) in up to 69% of cases 2, 3
- For definitive diagnosis in cases of uncertainty, percutaneous core needle biopsy to analyze for MDM-2 amplification should be performed 2
Treatment Algorithm
Observation
- Most lipomas are best left alone if they are asymptomatic and small 1
- Asymptomatic lipomas can be managed with observation and radiological surveillance 2
Indications for Treatment
- Symptomatic lipomas (causing pain, functional limitations)
- Rapidly growing lipomas 4
- Large lipomas (typically >5 cm) 2
- Lipomas with concerning features on imaging 2
- Cosmetic concerns (patient preference)
Treatment Options
Surgical Management (Primary Approach)
- Complete en bloc surgical excision is the standard treatment for symptomatic lipomas, with high success rates and low recurrence rates 2, 3
- Marginal resections as a complete en bloc specimen provide excellent rates of long-term local control 2
Alternative Non-Surgical Options
- High-intensity focused ultrasound (HIFU) has shown efficacy in noninvasively reducing lipoma size (mean volume reduction of 58.1%) without significant adverse effects 5
- Ultrasound-guided injection therapy using specialized agents (such as Aqualyx™) has shown promise with complete removal achieved in 70.59% of lipomas in one study 6
Special Considerations
Red Flags Requiring Urgent Referral
- Rapid increase in size 4
- Size larger than 5 cm 2
- Deep-seated location 2
- Pain not explained by size or location 2
- Concerning features on imaging (nodularity, septations, stranding) 2
Distinguishing Between Lipoma and Atypical Lipomatous Tumor (ALT)
- ALT/well-differentiated liposarcoma tends to be larger, deep-seated, and more common in the lower limb 2
- MRI features suggesting ALT include nodularity, septations, stranding, and larger relative size 2
- The definitive diagnostic test is molecular demonstration of MDM-2 cell cycle oncogene amplification by fluorescence in-situ hybridization 2, 7
Post-Treatment Follow-up
- Following surgical excision and post-operative wound care, patients can be discharged to primary care 2, 3
- Re-referral is only necessary if there is clinical suspicion of recurrence 2
- Recurrence rates for properly excised lipomas are low 2