Massive localized lymphedema (MLL) is a benign overgrowth of lymphoproliferative tissue that is primarily observed in adults with class III obesity. Patients present with a painless mass that has usually been present for a considerable period. Consultation of a healthcare professional typically takes place when MLL-related complaints interfere with daily living. Massive localized lymphedema is often termed “pseudosarcoma” due to its clinical similarity to sarcoma. Surgical excision is necessary to improve mobility, prevent recurrent infections, and rule out malignancy, but can be high-risk for individuals with class III obesity and multiple comorbidities. In this report, the authors present the case of a 47-year-old woman with a body mass index of 73 kg/m2 and MLL of the right medial thigh. She was successfully diagnosed and managed by local necrosectomy, wound debridement, maggot debridement therapy, and negative-pressure wound therapy by using a vacuum-assisted closure device. The diagnosis of MLL can be challenging because of its similarity to sarcoma; its pathogenesis and management are not completely elucidated. Despite surgery being the best described treatment, such an intervention itself can be challenging because patients often have multiple comorbidities and delayed diagnosis. The authors recommend that clinicians should consider nonsurgical treatment of MLL in high-risk patients who have necrotic wounds with fluid loss. The use of less invasive methods such as maggot debridement therapy followed by negative-pressure wound therapy can be useful in high-risk patients.