Description

• Accumulation of lymphatic fluid in the interstitial tissue causing swelling
• Lymphedema can develop when lymphatic vessels are missing or impaired (primary) or when lymph vessels are damaged or lymph nodes are removed (secondary).
• Most commonly occurs in the lower limb(s) (80% of cases) but also can occur in the arm(s), face, trunk, and external genitalia

Epidemiology

Incidence

• More common in females than in males
• Occurs in 13% of patients with breast cancer treated with surgery and 42% of those treated with surgery and radiation therapy
• Occurs in 25% of patients after gynecologic cancer surgery

Prevalence

• 120 million people worldwide are affected with primary lymphatic filariasis.
• 10 million people are affected by nonfilarial secondary lymphedema in the United States.

Etiology and Pathophysiology

• Primary lymphedema results from inherited conditions affecting the lymph nodes or lymphatic vessels.
• Secondary lymphedema:
  • Postoperative: gradual failure of distal lymphatics, which have to “pump” lymph at a greater pressure through damaged proximal ducts; the risk is higher with postoperative radiation because radiation reduces regrowth of ducts due to fibrous scarring.
  • Other causes include trauma, recurrent infection, malignancy (including metastatic disease), and marked obesity.
  • Most common cause in developing countries is filariasis (Wuchereria bancrofti).

Genetics

• Milroy disease is autosomal dominant and is diagnosed either at birth or within the 1st year of life.
• Lymphedema praecox has onset between the ages of 1 and 35 years.
• Lymphedema tarda occurs in those >35 years of age.
• Genetics referral is indicated with primary lymphedema and lymphedema tarda.

Risk Factors

• Filariasis: most common cause worldwide
• Lymphadenectomy or radiation therapy of lymph nodes, especially nodes of the underarm, groin, pelvis, and neck regions in cancer treatment (mastectomy, melanoma)
• Prior trauma, serious burns, infection of affected limb
• Obesity (body mass index: >50 kg/m²)
• Inflammatory disorders: arthritis, sarcoidosis, dermatitis

General Prevention

Maintenance of healthy body weight, treatment of congestive heart failure, and early recognition of infection, cancer, and venous insufficiency

Commonly Associated Conditions

Venous disease, morbid obesity, regional cancer, filarial disease (Africa and Asia)