Acrometastasis: a literature review

Acrometastases are a rare observation, and account for approximately 0.1% of metastases. Every age can be affected, with a male predominance. The most common primary cancer site is the lung, followed by the colo-rectal, breast and genito-urinary tract. They are most commonly seen in pre-terminal patients with wide-spread disseminated disease. Rarely, they may be the first presentation of occult silent cancer, mimicking a benign condition. There is no standard treatment. We reviewed last 20 years literature in order to describe the most common sites of primary tumours and the more commonly used treatments.

We searched the Cochrane Central Library (CENTRAL), MEDLINE/PubMed (from 1940 to February 2014), SCOPUS database, and EMBASE/Ovid using a combination of controlled vocabulary and text word terms.

Lung cancer was the first most common cause of acrometastases both in hands and feet, with 32.9% of all the cases; 20% of cases were renal cell cancer (RCC) metastases, followed by breast (12.9%) and colon (10%). Primary malignancies and site of metastasis (hand vs foot) suggest that the tumour cells reach the bones through the circulation and not the lymphatic system; in foot acrometastases Batson's plexus may play a fundamental role in dissemination.

Treatment depends on staging and tumor extent. Amputation or disarticulation is the most common approach. It allows a wide margin resection and pain control. In some cases palliative treatment with radiation therapy, bisphosphonates and chemotherapy have been attempted with good results. The prognosis of the patients with acrometastases is poor; the mean survival time after diagnosis is 7 (±7) months. Special reference needs to be made to metastasis from renal cell carcinoma; if treated with radical surgical resection and nephrectomy a better outcome and survival rate shall be expected.