Recurrent Kaposi sarcoma associated with Koebner phenomenon in two HIV-seronegative patients: Two case reports and a review of the literature.

Rationale: Koebner phenomenon is occasionally reported in patients affected by classic Kaposi sarcoma (KS).
Patient Concerns: Here, we report 2 cases of KS associated with Koebner phenomenon and the correlation of human herpesvirus 8 molecular analysis with the clinical outcome.
Interventions: In the first case, a patient with a history of sporadic cutaneous KS developed a recurrent lesion at the laryngeal tract, the site of a previous nodulectomy. In our second case, immunodeficiency induced by chemotherapy triggered the development of KS and Koebner phenomenon was limited to the skin at the site of safenectomy.
Lessons: Our observations suggest that careful planning of surgical treatment is required in immunocompetent and immunocompromised patients with a medical history of KS. Moreover, mucosal sites (both respiratory and in the gastrointestinal tract) should be considered as potential sites for KS development.
(Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.)