Spontaneous malignant transformation of a supratentorial pilocytic astrocytoma.

Pilocytic astrocytoma (PA) is a circumscribed neoplasia considered as a grade I astrocytoma by the World Health Organization. Its most common location is the cerebellum and it develops during the first two decades of the life. Prognosis is mostly excellent if gross-total resection can be achieved, with 10-year survival rates of up to 80%. Anaplastic or malignant transformation (MT) can rarely occur and is usually related to previous radiation. Spontaneous MT has exceptionally been reported. Histological criteria for diagnosis of MT are unclear, so no consensus exists. We present an atypical case of MT of a frontal PA without previous radiotherapy in a 28 years old patient. Also, we review the literature about prognostic factors of PA and discuss histological features that are considered as anaplastic or malignant in the PA.

Spontaneous malignant transformation of a supratentorial pilocytic astrocytoma

Pilocytic astrocytoma (PA) is a circumscribed neoplasiaconsidered as a grade I astrocytoma by the WorldHealth Organization. Its most common location is thecerebellum and it develops during the first two decadesof the life. Prognosis is mostly excellent if gross-totalresection can be achieved, with 10-year survival ratesof up to 80%. Anaplastic or malignant transformation(MT) can rarely occur and is usually related to previousradiation. Spontaneous MT has exceptionallybeen reported. Histological criteria for diagnosis ofMT are unclear, so no consensus exists. We present anatypical case of MT of a frontal PA without previousradiotherapy in a 28 years old patient. Also, we reviewthe literature about prognostic factors of PA and discusshistological features that are considered as anaplastic ormalignant in the PA (AU)

El astrocitoma pilocítico es un tumor bien delimitado,que según la clasificación de la OrganizaciónMundial de la Salud, se cataloga dentro del grupo de losastrocitomas de grado I. La localización más frecuentede esta neoplasia es el cerebelo y se manifiesta fundamentalmenteen las dos primeras décadas. Siempre ycuando se consiga una resección total, el pronóstico esmuy bueno, alcanzando una tasa de supervivencia del80% a los diez años. De manera excepcional, puedehaber casos de transformación anaplásica o maligna,normalmente asociados a radioterapia previa; se handescrito muy pocas situaciones de transformaciónespontánea. Existe mucha discusión a la hora de considerarlos criterios de malignidad desde un punto devista anatomopatológico. Presentamos un caso excepcionalde transformación anaplásica de un astrocitomapilocítico en un paciente de 28 años, al igual que revisamoslos criterios pronósticos de esta neoplasia y discutimoslos datos anatomopatológicos que se consideran deanaplasia o malignidad (AU)

[Presentation of 2 new cases of cutaneous angiomyolipomas and literature review]. / Angiomiolipomas cutáneos: aportación de dos casos y revisión de la literatura.

We present 2 new cases of cutaneous angiomyolipomas with very similar characteristics, located in the postauricular region of 2 women aged 58 and 52 years. The lesions measured 1.5 cm and 1 cm across and had been present for 5 and 2 years, respectively. Both presented a previously unreported clinical sign: change in size according to the ambient temperature. They had well defined borders and a predominance of smooth muscle and vessels, particularly arteries. In contrast to renal angiomyolipomas, which are often associated with tuberous sclerosis, these angiomyolipomas were negative for melanocytic immunohistochemical markers (human melanoma black-45 antigen and melanoma antigen recognized by T cells 1). The clinical characteristics of the 32 cases published until present are reviewed. The relationship of these tumors with angioleiomyomas and renal angiomyolipomas is discussed.

Angiomiolipomas cutáneos: aportación de dos casos y revisión de la literatura / Presentation of 2 New Cases of Cutaneous Angiomyolipomas and Literature Review

Presentamos dos nuevos casos de angiomiolipomas cutáneos de características muy similares. Se localizaban en región retroauricular de dos mujeres de 58 y 52 años. Tenían un tamaño de 1,5 y 1 cm de diámetro y una evolución de 5 y 2 años, respectivamente. Ambos presentaban un signo clínico no previamente descrito: cambio de tamaño según la temperatura ambiente. Estaban bien delimitados, el elemento predominante era el músculo liso y los vasos, sobre todo arteriales. A diferencia de lo que sucede con los angiomiolipomas renales frecuentemente asociados a esclerosis tuberosa, fueron negativos para los marcadores inmunohistoquímicos melanocitarios (HMB-45 y MART-1). Se revisan las características clínicas de los 32 casos publicados hasta la actualidad. Se discute la relación de estos tumores con los angioleiomiomas y los angiomiolipomas renales (AU)

We present 2 new cases of cutaneous angiomyolipomas with very similar characteristics, located in the postauricular region of 2 women aged 58 and 52 years. The lesions measured 1.5 cm and 1 cm across and had been present for 5 and 2 years, respectively. Both presented a previously unreported clinical sign: change in size according to the ambient temperature. They had well defined borders and a predominance of smooth muscle and vessels, particularly arteries. In contrast to renal angiomyolipomas, which are often associated with tuberous sclerosis, these angiomyolipomas were negative for melanocytic immunohistochemical markers (human melanoma black-45 antigen and melanoma antigen recognized by T cells 1). The clinical characteristics of the 32 cases published until present are reviewed. The relationship of these tumors with angioleiomyomas and renal angiomyolipomas is discussed (AU)

[Palatine tonsil lipoma]. / Lipoma de amígdala palatina.

Lipomatous tumors represent an unfrequent cause for upper aerodigestive tract neoplasms, specially concerning the palatine tonsils, that should be included in their differential diagnosis. A case of palatine tonsil lipoma in a 11 year-old girl is reported and a revision of the available literature and some considerations about this condition are provided.