Acrometastases.

Area of Science:

• Oncology
• Skeletal Metastasis Research

Background:

• Acrometastases (limb metastases distal to elbow/knee) are rare (0.1% of cancers).
• Lung cancer is the most common primary site (>50%), followed by colon, breast, and genitourinary tract.
• These metastases typically occur in patients with widespread disease but can be the initial presentation of occult cancers.

Purpose of the Study:

• To review the incidence, pathophysiology, clinical presentation, treatment, and prognosis of acrometastases.
• To elucidate the routes of tumor cell spread to the extremities.
• To discuss management strategies and outcomes for acrometastatic disease.

Main Methods:

• Review of existing literature on acrometastases.
• Analysis of proposed mechanisms for tumor cell dissemination to distal extremities.
• Summary of current treatment modalities and prognostic factors.

Main Results:

• Acrometastases predominantly affect men and are most commonly linked to lung cancer.
• Hematogenous spread through arterial circulation is the primary route to upper extremities; venous embolization via Batson's plexuses is implicated in lower extremity metastases.
• Amputative surgery is the main treatment, with palliative options including radiation and chemotherapy for unresectable cases.

Conclusions:

• Acrometastases have a poor prognosis (median survival <6 months).
• Surgical resection offers better outcomes in select cases, particularly for renal cell carcinoma with a long latency period.
• Understanding the unique spread patterns is crucial for diagnosis and management.