Mario Alexander Melo-Uribe

Spindle cell oncocytoma of the adenohypophysis

Spindle cell oncocytoma of the adenohypophysis (SCO) is defined as spindle to epithelioid cells with oncocytic appearance presenting in the adenohypophysis. In contrast to pituitary adenomas, the SCO does not show immunoreactivity for neuroendocrine markers and pituitary hormones but co-expressed vimentin, S-100 protein, epithelial membrane antigen (EMA), and antimitochondrial antibody MU213-UC clone 131-1. We describe an SCO in an adult, a 42-year-old woman whose magnetic resonance (MR) images documented an intrasellar lesion located in the hypophysis. Histopathological examination showed a tumor composed predominantly of spindle cells. Immunohistochemical studies showed positivity for vimentin, S10, EMA, and antimitochondrial antibody MU213-UC clone 131. Cytokeratin (CK) (AE1/AE3), glial fibrillary acidic protein (GFAP), chromogranin, synaptophysin, PGP9.5, CD57, desmin, D2-40, smooth muscle actin (SMA), Bcl-2, progesterone receptor, and CD34 were negative. Neuropeptides were negative. With electron microscopy, the neoplastic cells appear filled with mitochondria, well-formed desmosomes, but lacked secretory granules. SPO is a rare non-endocrine neoplasm of the adenohypophysis with benign biological behavior corresponding to WHO grade I.

Primary Yolk Sac Tumor of the Urachus

Introduction. Neoplasms originating from the urachus are rare. The most common urachal malignancy is adenocarcinoma, whereas extragonadal germ cell tumors, primarily of the urachus, are an extremely rare finding. Objective. To describe a primary yolk sac tumor (YST) of the urachus in an adult. Case report. A 44-year-old woman presented with 6 months of pelvic pain associated with a sensation of progressive mass growth. At the time of tumor resection, the tumor was found to be attached by a pedicle to the dome of the bladder, with no injury to the adjacent organs. Pathological study showed a neoplasm with epithelioid cells, pseudocysts, a myxomatous background, and Schiller-Duval body formations. Immunohistochemistry stains showed positivity to AE1/AE3, α-1-fetoprotein, and α-1-antitrypsin and negativity to other markers. Conclusion. An unusual case of a YST in the urachus is presented. This is the first reported adult case based on the authors’ bibliographic search.

Hamartoma mesenquimal rabdomiomatoso

Resumen El hamartoma mesenquimal rabdomiomatoso es una lesion congenita extremadamente rara, con caracteristicas macro y microscopicas que ayudan a su facil diagnostico; a pesar de lo anterior, se han descritomuy pocos casos. Presentamos el caso de una paciente de 18 anos de edad, con una masa en la region medial de cuello, pediculada, la cual se extirpo quirurgicamente obteniendo el diagnostico de hamartoma mesenquimal rabdomiomatoso. Se analizan las caracteristicas clinicas, macroscopicas, histologicas e inmunohistoquimicas, que permiten diagnosticar esta entidad. La asociacion con anomalias congenitas, aunque poco frecuente, debe ser valorada por el clinico.

Rhabdomyomatous Mesenchymal Hamartoma

Rhabdomyomatous mesenchymal hamartoma is an extremely rare congenital lesion, and very few cases have been reported even though its macroscopic and microscopic features make diagnosis easy. An 18-year-old woman consulted with a pedunculated mass in the medial region of her neck. The mass was surgically removed, and rhabdomyomatous mesenchymal hamartoma was diagnosed. The clinical, macroscopic, histologic, and immunochemical characteristics that allow diagnosis of this entity are discussed. Although association with congenital abnormalities is uncommon, this possibility should be assessed by the clinician.

Carcinomatosis meníngea como primera manifestación de carcinoma gástrico

Resumen La carcinomatosis meningea se define como la infiltracion maligna y generalizada de las meninges debido a la siembra y crecimiento de celulas cancerigenas dentro del espacio leptomeningeo. Se presenta mas a menudo en pacientes con enfermedad neoplasica diseminada, pero se puede presentar despues de un intervalo libre de enfermedad e, incluso, ser la primera manifestacion de cancer. Los tumores primarios mas habituales en la poblacion adulta son los de mama (30%-50%), pulmon (15%-25%), melanoma (11%) y cancer gastrico (0,16%- 0,69%); ello, en marcado contraste con la poblacion pediatrica, en la cual la leucemia linfocitica aguda es mas comun. Se describe un caso de autopsia realizada a un paciente con sintomas psiquiatricos, sin antecedentes de importancia, que cursa con deterioro neurologico progresivo y fatal, y en quien los estudios anatomopatologicos realizados evidencian carcinomatosis meningea por un adenocarcinoma gastrico avanzado que es descubierto de novo post mortem.

Oncocytoma of the Lacrimal Caruncle

1. Huang YH, Chuang YH, Kuo TT, Yang LC, Hong HS. Vulvar syringoma: a clinicopathologic and immunohistologic study of 18 patients and results of treatment. J Am Acad Dermatol. 2003;48:735-9. 2. Tay YK, Tham SN, Teo R. Localized vulvar syringomas-an unusual cause of pruritus vulvae. Dermatology. 1996; 192:62-3. 3. Mahiques L, Martinez-Menchon T, Martinez-Aparicio A, Fortea JM. Siringomas vulvares. Actas Dermosifiliogr. 2004;95:397-8. LETTERS TO THE EDITOR

Cutaneous Collision Tumor Associated With Porocarcinomatous and Angiosarcomatous Components: A Potential Diagnostic Pitfall.

Sarcomatoid eccrine porocarcinoma (SEP) is a very rare malignancy including epithelial and mesenchymal components exhibiting pleomorphic cells, nuclear hyperchromasia, and high mitotic activity in both elements. To date, only 6 cases of this uncommon neoplasm have been reported, corresponding to women over 70 years of age with ulcerated skin lesions. The authors describe the first sarcomatoid eccrine porocarcinoma in a 75-year-old male patient with a right hallux lesion, presenting a collision tumor with a mixed population of epithelial cells and a spindle cell angiosarcomatous mesenchymal component each expressing distinct and nonoverlapping morphologic and immunohistochemical features of epithelial and mesenchymal differentiation.

Sarcoma sinovial digital

Resumen El sarcoma sinovial es una entidad bien definida clinica y morfologicamente y, a pesar de su nombre, es muy raro en las cavidades articulares. Este sarcoma afecta zonas sin relacion aparente con las estructuras sinoviales y representa entre el 5% y el 10% de todos los sarcomas de los tejidos blandos. Se encuentra con mayor frecuencia en las extremidades, especialmente en las inferiores, donde tiende a localizarse en la vecindad de las grandes articulaciones; se han informado muy pocos casos de sarcomas sinoviales en las manos o los pies, con una evolucion clinica favorable. Asi mismo, es mas frecuente de 15 a 40 anos de edad (con una edad media de 34 anos). Este articulo presenta el caso de una mujer adulta a quien se le realizo el diagnostico histopatologico e inmunohistoquimico de un sarcoma sinovial en el quinto dedo de la mano derecha.