Stewart–Treves syndrome

Overview

Stewart–Treves syndrome is a rare and aggressive cutaneous angiosarcoma that arises in the setting of chronic lymphedema, most commonly affecting the upper limbs following mastectomy and lymph node dissection for breast cancer. First described by Drs. Fred Stewart and Norman Treves in 1948, this syndrome represents a malignant transformation of lymphatic vessels in chronically swollen tissues.

The syndrome is notable for its rapid progression and poor prognosis. It underscores the serious complications that can arise from longstanding lymphedema, highlighting the importance of vigilant monitoring in at-risk patients.

Causes

The primary cause of Stewart–Treves syndrome is chronic lymphedema, which leads to lymphatic stasis, tissue hypoxia, and immune dysregulation. These factors contribute to malignant transformation of endothelial cells in the lymphatic vessels. Key contributing factors include:

• Chronic lymphedema: Typically develops after lymph node dissection, radiation therapy, or trauma disrupting normal lymphatic drainage.

• Previous breast cancer treatment: Most commonly occurs in patients who have undergone mastectomy with axillary lymph node dissection and/or radiotherapy.

• Immunological impairment: Chronic lymphedema impairs local immune surveillance, increasing susceptibility to malignancy.

• Genetic and environmental factors: May play a role but are not well defined.

Symptoms

Stewart–Treves syndrome typically presents several years after the onset of chronic lymphedema. Symptoms include:

• Appearance of bruised, purplish, or erythematous plaques or nodules on the chronically swollen limb

• Rapidly enlarging skin lesions that may ulcerate or bleed

• Pain or tenderness in the affected area

• Progressive worsening of lymphedema

• Regional lymphadenopathy or systemic symptoms in advanced disease

Early lesions may resemble benign skin changes, delaying diagnosis.

Diagnosis

Diagnosis requires a high index of suspicion in patients with chronic lymphedema presenting with suspicious skin lesions. Diagnostic steps include:

• Clinical examination: Inspection and palpation of skin lesions and assessment of lymphedema severity.

• Skin biopsy: Essential for definitive diagnosis, revealing malignant endothelial cells forming irregular vascular channels consistent with angiosarcoma.

• Immunohistochemistry: Positive staining for endothelial markers such as CD31, CD34, and factor VIII-related antigen.

• Imaging studies: MRI or CT scans to assess local invasion and metastatic spread.

• Staging workup: Including PET scans and chest imaging to detect distant metastases.

Treatment

Treatment of Stewart–Treves syndrome is challenging due to its aggressive nature and high recurrence rates. Management strategies include:

Surgical Intervention

• Wide local excision: Removal of the tumor with clear margins.

• Amputation: Often required in extensive or recurrent disease to achieve local control.

Radiation Therapy

• Used as an adjunct to surgery or for unresectable tumors.

• May help reduce local recurrence.

Chemotherapy

• Systemic chemotherapy agents such as paclitaxel, doxorubicin, or ifosfamide may be used, especially in metastatic or advanced cases.

• Newer targeted therapies and immunotherapies are under investigation but are not yet standard of care.

Supportive Care

• Management of lymphedema with compression therapy, physiotherapy, and skincare.

• Pain control and wound care for ulcerated lesions.

Prognosis

Stewart–Treves syndrome carries a poor prognosis due to its aggressive behavior and tendency for local recurrence and distant metastasis. The overall 5-year survival rate is estimated to be less than 10–20%. Early detection and radical treatment improve outcomes but are often hampered by delayed diagnosis.

Close monitoring of patients with chronic lymphedema is essential to detect early malignant changes. Multidisciplinary management involving oncologists, surgeons, dermatologists, and lymphedema specialists is crucial to optimize care and improve quality of life.