Diferencias y controversias entre el reporte de patología y la interpretación clínica en patología tiroidea. II PARTE: Aspectos patológicos y métodos diagnósticos con impacto terapéutico / Thyroid diseases: Differences and controversies between the pathology report and clinical interpretation. PART II: Pathological aspects and diagnostic methods with therapeutic impact

Resumen Como revisamos en la primera parte1 hay algunos conceptos que deben ser considerados para el adecuado manejo médico por parte del equipo clínico que recibe el reporte de patología, de esta misma manera existen aspectos por parte del patólogo que este debe conocer, los cuales tienen impacto terapéutico. En esta segunda parte queremos revisar algunos conceptos que son de importancia por parte del patólogo que aplican directamente sobre la interpretación del clínico, como: procesamiento macroscópico; estudio de la citología por aspiración con aguja fina (FNA) vs. biopsia trucut, utilidad de la biopsia por congelación y de la inmunohistoquímica, así como los métodos e imágenes diagnósticas.

Abstract As was reviewed in the first part, there are some concepts that should be considered for the appropriate medical management by the medical team that receives the pathology report. Similarly, there are some aspects that the pathologist should know, such as those that can have therapeutic impact. In this second part, a short review is presented on some of the concepts that are of importance to the pathologist that apply directly to the interpretation by the clinician, such as the macroscopic processing, the cytology study of the fine-needle aspirate (FNA) vs. "tru-cut" biopsy, the usefulness of the frozen biopsy, and immunohistochemistry, as well as diagnostic methods and diagnostic images.

Diferencias y controversias entre el reporte de patología y la interpretación clínica en patología tiroidea. I parte: Factores pronósticos / Thyroid pathology: differences and controversies between the pathology report and clinical interpretation. Part I: prognostic factors

Resumen El cáncer de la glándula tiroides es una neoplasia cuya detección, diagnóstico y tratamiento se realiza de manera interdisciplinaria, por lo tanto el diagnóstico definitivo histopatológico debe ser completo y claro; de modo que pueda ser interpretado de la misma manera por parte del grupo médico tratante. De manera frecuente, los médicos no patólogos que reciben el reporte de un estudio histopatológico de tiroides se enfrentan con dificultades al momento de interpretar el reporte histopatológico y，por lo tanto, en definir la posterior conducta médica. El objetivo de este primer artículo es revisar de manera breve algunos de los diferentes temas que más generan dudas en la interpretación del reporte histopatológico y de las técnicas diagnósticas usadas en patología por parte de los médicos tratantes que tienen un impacto en las decisiones clínicas originadas a partir de la clasificación, estadificación, pronóstico y seguimiento de la enfermedad.

Abstract Cancer of the thyroid gland is a neoplasia for which its detection, diagnosis and treatment is interdisciplinary. For this reason, the definitive diagnosis by histopathology should be complete and clear so that it can be interpreted in the same way by the treating medical group. Non-pathology physicians who receive the report of a histopathological study of the thyroid often have difficulties when interpreting the report and therefore in defining the subsequent medical behaviour. The objective of this first article is to review briefly some of the different subjects that generate most doubts in the interpretation of the histopathology report, and the diagnostic techniques used in pathology by the attending physicians that have an impact on clinical decisions arising from the classification, staging, prognosis, and follow-up of the disease.

Linfoma leptomeníngeo primario. Reporte de tres casos y revisión de la literatura / Primary leptomeningeal lymphoma. Report of three cases and review of the literature

El linfoma leptomeníngeo primario (LLMP) es una entidad con baja frecuencia de presentación, representa del 1% al 2,4% de los linfomas primarios del sistema nervioso central; las variedades histológica más observadas son el linfoma de la zona marginal tipo MALT, el linfoma B de célula grande difuso y el linfoma linfoblástico de células B. La localización y su extensión determinan las manifestaciones clínicas; en radiología se prefieren las imágenes con medios de contraste, ya que tienden a confundirse con meningiomas como la primera impresión diagnóstica y son la cirugía y los estudios de patología los que confirman el diagnóstico. La quimioterapia es la base del tratamiento en esta entidad, la radioterapia se deja como una opción secundaria. El propósito de este trabajo es presentar tres casos clínicos representativos de LLMP y las variantes por imágenes de radiología, la revisión enfocada de la literatura y el tratamiento de esta infrecuente patología.

Primary Leptomeningeal lymphmoma (PLML) is a low frequency neoplasm representing 1% to 2,4% of primary lymphomas of the central nervous system (CNS). The most frequent histological variety is the extranodal marginal zone lymphoma (MALT lymphoma), but other variants are reported such as diffuse large cell B-cell lymphoma (DLBCL). The location and extent determine the clinical manifestations. In radiology, images with contrast are preferred to difference from meningiomas which are the main differential diagnosis; nevertheless surgery and histology confirm the diagnosis. Chemotherapy is the mainstay of treatment and radiation therapy is a secondary alternative. The purpose of this paper is to present three cases of PML, the radiological variants and to conduct a focused literature review with treatment of this pathology.

Carcinoma anficrino de glándula mamaria. Reporte de un caso inusual / Breast amphicrine carcinoma. Report of an unusual case

Los tumores anficrinos de la glándula mamaria son lesiones duales muy poco frecuentes con diferenciación epitelial y neuroendocrina de una misma célula. Nosotros presentamos el caso de una mujer con masa en el seno derecho. El estudio histopatológico mostró un tumor maligno constituido por células pequeñas entremezcladas con algunas células con aspecto en anillo de sello. El uso de anticuerpos monoclonales mostró inmunoreactividad para marcadores epiteliales y neuroendocrinos en las células malignas. Estas características permitieron hacer el diagnóstico de un tumor anficrino basado en la expresión en la misma célula de marcadores epiteliales y neuroendocrinos. El diagnóstico diferencial debe realizarse con los tumores de colisión o con metástasis. La interpretación rigurosa de la inmunohistoquímica en las células neoplásicas en un tumor anficrino es útil para distinguir esta entidad de otras patológicas con características morfológicas similares.

Amphicrine tumours of the mammary gland are very rare dual lesions with epithelial and neuroendocrine differentiation in the same cell. We report the case of a woman with a mass in the right breast. The histopathology study showed a malignant tumour formed by small cells inter-mixed with some cells with a signet ring appearance. The use of antibodies showed immunoreactivity for epithelial and neuroendocrine markers in the malignant cells. These characteristics enable the diagnosis of an amphicrine tumour, based on the expression of epithelial and neuroendocrine markers in the same cell. The differential diagnosis must be made with collision tumours or with metastasis. The rigorous interpretation of the immunohistochemistry in the malignant cells in an amphicrine tumour is useful in order to distinguish this tumour from other diseases with similar morphological characteristics.

Tumor del estroma gastrointestinal gástrico con metástasis inusual al cráneo / Gastric gastrointestinal stromal tumor with unusual skull metastasis

Los tumores del estroma gastrointestinal GIST, se originan en la pared del tracto digestivo desde el esófago al ano. Aproximadamente 25% de los GIST gástricos son clínicamente malignos y desarrollan metástasis principalmente al hígado, menos comúnmente a tejidos blandos y hueso. Se presenta el caso de un paciente con GIST gástrico y metástasis al hígado e inusualmente al cráneo.

Gastrointestinal stromal tumors (GISTs) originate in the wall of the digestive tract from the esophagus to the anus. Approximately 25% of gastric GISTs are clinically malignant. Most often they metastasize to the liver, less commonly to soft tissues and bone. The clinical case of a patient with a gastric GIST, liver and unusual cranial metastasis is presented.

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 malignant solitary fibrous tumor/hemangiopericytoma of the parotid gland / Tumor fibroso solitario maligno primario/hemangiopericitoma de la glándula parótida

Solitary fibrous tumor (SFT) was first described in the pleura by Lietaud in 1767; later in 1870, Wagner described the localized nature of this type of tumor and Klemperer and Rabin classified pleural tumors into two types: diffuse mesotheliomas and localized mesotheliomas. Recent years have seen the redefinition of this neoplasm, due to better technology; it is now proven that this neoplasm may have multiple different extrapleural origins including the head and neck regions. This diversity of locations is related to the particular mesenchymal histogenesis of SFT which allows its development from very unusual sites such as the salivary glands (SGs). In this particular site, this neoplasm is very infrequent and most of reported cases refer to benign disease, with just one case informed so far of primary malignant SFT (AU)

El tumor fibroso solitario (TFS) fue primeramente descrito en la pleura por Lietaud en 1767; posteriormente en 1870, Wagner describió la naturaleza localizada de este tipo de tumor y Klemperer y Rabin, en 1931, clasificaron los tumores pleurales en dos tipos: mesoteliomas difusos y mesoteliomas localizados. En los últimos años se ha redefinido esta neoplasia, debido a la mejora de las tecnologías; ahora se ha probado que puede tener múltiples y diferentes orígenes extra-pleurales, incluyendo la región de cabeza y cuello. Esta diversidad de localizaciones se relaciona con la histogénesis mesenquimal particular del TFS, que permite su desarrollo desde localizaciones muy inusuales tales como las glándulas salivares (GS). En esta localización particular este tumor es muy infrecuente, y muchos casos reportados se refieren a una enfermedad benigna, con un único caso informado hasta la fecha de TFS maligno primario (AU)

[Primary malignant solitary fibrous tumor/hemangiopericytoma of the parotid gland]. / Tumor fibroso solitario maligno primario/hemangiopericitoma de la glándula parótida

Solitary fibrous tumor (SFT) was first described in the pleura by Lietaud in 1767; later in 1870, Wagner described the localized nature of this type of tumor and Klemperer and Rabin classified pleural tumors into two types: diffuse mesotheliomas and localized mesotheliomas. Recent years have seen the redefinition of this neoplasm, due to better technology; it is now proven that this neoplasm may have multiple different extrapleural origins including the head and neck regions. This diversity of locations is related to the particular mesenchymal histogenesis of SFT which allows its development from very unusual sites such as the salivary glands (SGs). In this particular site, this neoplasm is very infrequent and most of reported cases refer to benign disease, with just one case informed so far of primary malignant SFT.

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.