A 30-year-old woman developed a slowly progressive reddish-violet multinodular rubbery lesion, measuring 20 x 10 cm in diameter, on the upper outer quadrant of her right breast four years after the surgical excision of a dermatofibrosarcoma protuberans (DFSP) in the same area. The diagnosis of DFSP was confirmed histologically and by positive immunomarkers at immunohistochemistry. A complete excision was performed and after a 2-year follow-up no recurrence was observed. It should be emphasized that DFSP of the breast is a rare occurrence.

Presentamos a una paciente de 30 años de edad, que desarrolla en forma lenta y progresiva una tumoración rojo violácea multinodular de consistencia duroelástica de 20cm por 10cm en el cuadrante superoexterno de su mama derecha, a los cuatro años de habérsele extirpado un dermatofiborsarcoma protuberans (DFSP) en dicha localización. El estudio histopatológico y la imnunomarcación confirmaron la recidiva. A los dos años de la nueva intervención quirúrgica no existen evidencias de lesión neoplásica. Debe considerarse infrecuente la localización mamaria de esta patología.

The family Polyomaviridae is composed of small, non-enveloped, double-stranded DNA viruses widely used to study cell transformation in vitro and tumor induction in vivo. The development of pilomatricomas in mice experimentally infected with polyomavirus led us to detect the viral major capsid protein VP-1 in human pilomatricomas. This tumor, even uncommon, is one of the most frequent benign hair follicle tumors in humans and is composed of proliferating matrix cells that undergo keratinization, and form cystic neoplasms. The detection of VP-1 was performed using the peroxidase-antiperoxidase technique in paraffin-embedded slides with a specific primary serum. Adjacent slides treated with normal rabbit serum as a primary were employed as internal control. Positive and negative controls were also employed as well as slides of lesions caused by human papillomavirus to rule out any unspecific cross-reactivity. In 4 out of 10 cases polyomavirus VP-1 was clearly detected in nuclei of human pilomatricomas proliferating cells, in a patchy pattern of distribution. The controls confirmed the specificity of the immunocytochemical procedure. These results could indicate either an eventual infection of the virus in already developed tumors or alternatively, a direct involvement of polyomavirus in the pathogenesis of some pilomatricomas. The recent discovery of a new human polyomavirus associated with Merkel cell carcinomas has been a strong contribution to better understand the pathogenesis of some human uncommon skin cancers. Hopefully the results reported in this work will encourage further research on the role of polyomavirus in other human skin neoplasms.

La familia Poliomaviridae está compuesta por virus oncogénicos pequeños, no envueltos, con ADN de doble cadena. En un modelo experimental murino pudimos desarrollar pilomatricomas inducidos por la inoculación de virus polioma. Eso nos llevó a estudiar la posibilidad de que otro virus polioma estuviera involucrado en la génesis de pilomatricomas humanos. Los pilomatricomas son neoplasias benignas originadas en las células de la matriz del folículo piloso, que van madurando hacia la queratinización y terminan formando tumores quísticos. Se empleó la técnica de peroxidasa-antiperoxidasa para detectar VP-1 de polioma en cortes parafinados, usando un suero primario específico contra esa proteína. Como controles internos se trataron cortes adyacentes con suero normal de conejo como primario. Se emplearon, además, controles positivos y negativos y cortes de lesiones producidas por el virus papiloma humano. En 4 de los 10 casos estudiados se observó la presencia de VP-1 en los núcleos de células tumorales distribuidas en focos dispersos. Los controles empleados permitieron descartar cualquier inespecificidad de la reacción inmunocitoquímica. Estos resultados podrían indicar una eventual replicación del virus en tumores en desarrollo o, alternativamente, podrían significar un compromiso directo de poliomavirus en la etiopatogenia de algunos pilomatricomas. Recientemente se ha descubierto un nuevo virus polioma humano asociado al carcinoma de células de Merkel. Quizás los resultados descriptos en este trabajo permitan profundizar en el estudio de la asociación entre poliomavirus y neoplasias cutáneas humanas.

A pitiríase rósea purpúrica constitui doença rara e 10 casos foram publicados na Europa e EUA. O quadro clínico cutâneo é a forma hemorrágica ou purpúrica com variável descamação marginal. Relata-se o caso de um homem de 25 anos de idade com lesões na região escapular. A revisão da literatura enfatiza o diagnóstico diferencial das lesões purpúricas. Segundo Lilacs e Medline, não foram relatados casos na literatura latino-americana.

Purpuric pityriasis rosea is an unusual disease with ten published cases in the American and European literature. The main feature is an hemorrhagic or purpuric eruption with or without scaling. A case is reported of a 25-year-old man with skin lesions affecting the scapular region. The review emphasizes the differential diagnosis of purpuric cutaneous diseases. According to LILACS and MEDLINE, no similar case has been reported in the Latin-American literature.