Foot metastasis: Current knowledge

Foot metastasis are rare and often overlooked due to non-specifical symptoms. This often leads to misdiagnosis delaying the right diagnosis. Metastatic disease of the foot is rare. Foot pain and swelling may be the presenting symptom of an occult malignancy. If metastatic disease is not kept in the differential diagnosis of foot pain, diagnosis and treatment will be delayed. The purpose of this study was to analyze articles presenting cases of foot metastasis to provide a more accurate incidence of symptomatic foot acrometastasis as well as to review the clinical course and outcomes. Studies were searched on PubMed/Medline from the inception to February 2020. All studies included in the review presented foot metastasis either with or without a known primary tumor. Most of the articles were case reports, to which we added two case reports of foot acrometastasis produced by our Institute. Forty-three studies with a total of 45 patients were included in this review. The literature published mostly concerning case reports about old patients (average age: 63,2), in a late phase of their disease. Lung cancer appeared to be the most common primary tumor, followed by endometrial and breast cancer. In the 36% of the cases foot metastasis were found when the primary site was still unknown. Calcaneus and metatarsal bones were the most common bones involved. Surgical solution is rare, the chosen treatments are often of palliative care. Prognosis was often poor, death occurred within 2 years since the discovery of foot metastasis in about 50% of cases.