Cutaneous Metastasis: A Prelude to a Sinister Outcome

Abstract

Cutaneous metastasis is an uncommon presentation of primary internal malignancy presenting for dermatology cross-referrals with an incidence ranging from 0.7 to 10%. It may be the first presentation of an underlying primary malignancy. The primary may remain unknown in up to 3 to 5% cases. Detailed evaluation of clinical presentation with emphasis on cytomorphological features, immunohistochemistry, and imaging aids in identification of an unknown primary. Incidence of leukemia cutis has been reported to be as high as 22% and is associated with poor prognosis. In majority of the patients, presentation of cutaneous metastasis signifies advanced disease with ominous outcome. It correlates with either treatment failure or reoccurrence of previously treated malignancy. Though cutaneous metastatic lesions are amenable to early visual detection, this entity may be easily mistaken for common dermatological conditions and hence goes unrecognized. Lesions of cutaneous metastasis may bear therapeutic and prognostic implications. Therefore, a very high index of suspicion is warranted to accurately and timely diagnose such manifestations of hidden malignancies. We report three such cases that highlight the protean manifestations of internal malignancies.

Keywords

• adenocarcinoma
• cutaneous metastasis
• carcinoma of unknown primary
• malignancy