Abstract Porokeratosis is a skin disorder clinically characterized by annular plaques with keratotic borders resembling the Great Wall of China and histopathologically by cornoid lamellae. The disease has several clinical variants. Porokeratosis ptychotropica, which has recently become part of these variants, is quite rare and little known. The entity is characterized by verrucous plaques – which may resemble a psoriasis plaque – that affect the regions of the buttocks, most commonly the gluteal cleft, with or without extremity involvement. Itching is often present. We report a rare case of porokeratosis ptychotropica and highlight its unusual manifestation (single plaque), the first case reported in the Brazilian literature.

AbstractCutaneous metastasis is a rare manifestation of visceral malignancies that indicates primarily advanced disease. Due to its low incidence and similarity to other cutaneous lesions, it is not uncommon to have a delayed diagnosis and a shortened prognosis. We describe the case of a patient who presented with a cutaneous nodule in the sternal region as a first sign of malignancy.

Abstract Glomus tumors originate from modified perivascular muscle cells. The most common form is the solitary one. The multiple form may be associated with dominant genetic inheritance. We report a case of a patient with hemangiomatous lesions on the calcaneus and wrist since birth. In 6 years, there was progression of lesions throughout the body. Multiple glomangiomas are asymptomatic and more common in childhood. They can be confused with other vascular malformations. Histopathological diagnosis is essential. The case shows a type 2 segmental manifestation that can be explained by genetic mutation leading to the loss of heterozygosity. As the child grows, the lesions may disseminate due to mutation in distant parts of the skin. Literature shows few reports. The treatment is conservative.

Sarcoidosis is a multisystem granulomatous disease of unknown cause. The osteoarticular involvement in sarcoidosis is rare and is often associated with cutaneous and long-standing chronic multisystem disease. More common in black women, osseous sarcoidosis is difficult to diagnose, with an incidence of 3 to 13%. The most characteristic radiological clinical picture evidences rounded, well-defined cysts, with no periosteal reaction and without peripheral sclerosis. The small bones of hands and feet are the most frequently involved sites. This report aims to demonstrate a rare case of osteoarticular sarcoidosis with characteristic clinical presentation, and highlight the importance of detecting osteoarticular involvement in this pathology.

Ewing sarcoma is a primitive neuroectodermal tumor rarely occurs in the skin and sobcutaneous tissues. Generally Ewing's sarcoma is a primary bone tumor, but when present in soft tissues it characterizes an extremely uncommon clinical picture. It usually involves the deep subcutaneous tissue or muscles, and more rarely occurs like a primary skin cancer. Most patients are white, women, and in the second decade of life. The clinical features are a superficial mass, in average measuring 2-3 cm, of soft consistency, freely mobile and sometimes painful. The more affected locations are upper and lower extremities, trunk, head, neck or multiple lesions. The presence of metastases is very rare.