TY - CHAP M1 - Book, Section TI - Cutaneous Metastases A1 - Sannaa, Ghadah Al A1 - Lazar, Alexander J. A2 - Barnhill, Raymond L. A2 - Crowson, A. Neil A2 - Magro, Cynthia M. A2 - Piepkorn, Michael W. A2 - Kutzner, Heinz A2 - Desman, Garrett T. PY - 2020 T2 - Barnhill's Dermatopathology, 4e AB - A metastasis is a neoplasm that has spread from its original site such that it is no longer in continuity with, and often not in close proximity to, the primary lesion. Neoplasms can invade the skin by contiguous spread or may spread into the skin by direct extension into surgical scars and needle biopsy tracts, but the usual pathway of regional or distant metastases is believed to involve lymphatic or blood vessels.1-3 Such lymphatic and vascular spread may be not only intraluminal but also extravascular by means of tumor cell migration along the abluminal surfaces of vascular channels. The frequency of cutaneous metastases in patients with cancer ranges from 0.6% to 10.4% in various studies, accounting for approximately 2% of all skin tumors.4-10 Autopsy studies reporting lower incidence rates ranging from 1% to 5.3% might underestimate the frequency of cutaneous metastases both due to successful antecedent therapy and incomplete postmortem skin examination.11 In a study of 4,020 patients with metastatic carcinoma and melanoma, 420 patients (10.4%) had cutaneous metastases, and cutaneous metastases were the first sign of extranodal metastatic disease in 306 patients (7.6%).10 In another study of 7,316 cancer patients, 5% had skin involvement. Skin involvement was the first sign of cancer in less than 1% of patients.9 A little more than a third of these rare patients had direct extension of the primary cancer into the skin, a third had local (satellite) metastases, and only about a quarter represented distant metastases to the skin. Thus, although skin metastases are in general relatively uncommon, they can quite rarely be the initial presentation of an internal malignancy. SN - PB - McGraw Hill Education CY - New York, NY Y2 - 2024/04/18 UR - dermatology.mhmedical.com/content.aspx?aid=1178407978 ER -