Management of Lipomas in Both Flanks

Diagnostic Approach

Initial evaluation should include ultrasound as an effective triage tool to determine if the masses are indeed lipomas, particularly in patients with a history of similar growths, according to the British Journal of Cancer 3, 4
If the ultrasound confirms lipomatous appearance but there is diagnostic uncertainty, MRI should be performed to further evaluate the masses, as recommended by the British Journal of Cancer 1, 2
MRI with expert review can differentiate between benign lipomas and atypical lipomatous tumors (ALT) in up to 69% of cases, with a high degree of accuracy, as reported by the British Journal of Cancer 5, 1
For definitive diagnosis in cases of uncertainty, percutaneous core needle biopsy to analyze for MDM-2 amplification should be performed, as suggested by the British Journal of Cancer 5, 1

Complete en bloc surgical excision is the standard treatment for symptomatic lipomas, with a high success rate and low recurrence rate, as reported by the British Journal of Cancer 5, 1
Marginal resections as a complete en bloc specimen will give excellent rates of long-term local control, according to the British Journal of Cancer 5, 1
Observation with radiological surveillance can be considered for asymptomatic, small lipomas or in patients with significant comorbidities, as recommended by the British Journal of Cancer 5, 1

ALT/well-differentiated liposarcoma tends to be larger, deep-seated, and more common in the lower limb, with distinct MRI features, as reported by the British Journal of Cancer 3, 6
MRI features suggesting ALT include nodularity, septations, stranding, and larger relative size, with a high degree of specificity, as described by the British Journal of Cancer 5, 1
The definitive diagnostic test is molecular demonstration of MDM-2 cell cycle oncogene amplification by fluorescence in-situ hybridization, as recommended by the British Journal of Cancer 5, 1

Consider urgent referral if the lipoma is rapidly increasing in size, larger than 5 cm, deep-seated, painful, or shows concerning features on imaging, as suggested by the British Journal of Cancer 7, 6

Following surgical excision and post-operative wound care, patients can be discharged to primary care, with a low risk of recurrence, as reported by the British Journal of Cancer 5, 1
Re-referral is only necessary if there is clinical suspicion of recurrence, with a high degree of accuracy, as recommended by the British Journal of Cancer 5, 1
Recurrence rates for properly excised lipomas are low, with a high degree of success, as reported by the British Journal of Cancer 1, 2