A 43-year-old women presented with a 5-mm violaceous papule with a surrounding annular, eccymotic halo on the right side of the flank (Fig. 1). The patient stated that the lesion had appeared 1-week ago. She described the onset of a similar lesion at the same place 1-year ago and the lesion had regressed completely within 2 months without any treatment. The patients past medical history included diabetes mellitus, depression and lower extremity venous insufficiency and she had been using metmofine, sertraline and calcium dobesilat therapies. The patient did not give any history of trauma to the area of the lesion. Histopathology of the lesion revealed ectatic vascular spaces lined with a single layer of prominent plump endothelial cells protruding in to the lumen of vessels and the patient was diagosed as THH (Fig. 2).

The patient’s informed consent was obtained.

Prior to the study, patient gave written consent to the examination and biopsy after having been informed about the procedure

THH is a solitary vascular neoplasm which was first described by Santa Cruz and Aronburg in 1988 [4]. Though the etiology of THH is not clear trauma to a pre-existing hemangioma and influence of sex hormones have been proposed [5,6]. THH occurs predominanly on the proximal extremities and trunk and often presents as a small violaceous papule or nodule with an ecchymotic halo, which leads to a targetoid appearance [2,3]. The halo may expand peripherally and eventually disappear [3]. However the halo may not be present in all cases and the term hobnail hemangioma is used to describe the non-targetoid variant [2]. Cyclic changes have been described in palpability, size and color of THH [5,7].

Histopathologically ectatic vascular spaces which are often lined with a single layer of prominent plump endothelial cells protruding in to the lumen of vessels are observed in the papillary dermis and vascular spaces and collagen dissecting narrow vessels are observed in the deeper dermis [5,6].

The clinical differantial diagnosis includes melanocytic nevus, melanoma, dermatofibroma, hemangioma, insect bite reaction and the histopathological differential diagnosis includes Kaposi’s sarcoma, retiform hemangioendothelioma, eosinophilic hemangioma, progressive lymphangioma and angiokeratoma [6,7].

THH may be removed for diagnostic and cosmetic purposes and there is no recurrence after excision [3].

We present this case as complete and spontaneous regression with subsequent recurrence has been very rarely reported in the literature.

The examination of the patient was conducted according to the Declaration of Helsinki principles. Written informed consent was obtained from the patient for publication of this article