0000000000135749
AUTHOR
Gema Nieto
Congenital undifferentiated sarcoma associated to BCOR-CCNB3 gene fusion
Small round cell sarcomas are aggressive bone and soft tissue tumors that predominantly affect children and young adults. A new group of sarcomas with a recurrent BCOR-CCNB3 gene fusion has been recently identified in previously unclassifiable small round cell sarcomas. BCOR-CCNB3 sarcomas share clinical and pathologic similarities with Ewing sarcoma, but show a stronger male predilection and less aggressiveness, as well as distinct gene expression profiling and pangenomic SNP array analyses. We report the unusual case of a congenital BCOR-CCNB3 retroperitoneal sarcoma in a female born at 34th gestational week, which was diagnosed in necropsy after 21hours of life. Immunohistochemical analy…
Assessing molecular subtypes of gastric cancer: microsatellite unstable and Epstein-Barr virus subtypes. Methods for detection and clinical and pathological implications.
Background The molecular classification of gastric cancer recognises two subtypes prone to immune checkpoint blockade: the microsatellite unstable and the Epstein-Barr virus (EBV)-related tumours. We aim to assess the concordance between immunohistochemistry and PCR for microsatellite status evaluation, and explore the value of microsatellite instability (MSI) and EBV as predictive survival factors. Material and methods We collected 246 consecutively diagnosed gastric cancer cases in all stages and evaluated the microsatellite status using immunohistochemistry for mismatched repair (MMR) proteins and PCR. EBV expression was studied through in situ hybridisation. Results Forty-five (18%) cas…
Sarcoma fibromixoide de bajo grado, un diagnóstico diferencial esencial en los tumores mixoides de apariencia benigna
Resumen El sarcoma fibromixoide de bajo grado es una neoplasia poco frecuente que afecta preferentemente a adultos jovenes. Se trata de un tumor fibroblastico de apariencia enganosamente benigna que puede presentar recurrencias locales y metastasis a distancia tardias. Presentamos el caso de una nina de 11 anos que presentaba una lesion en el muslo, de la que se realizo exeresis completa. El estudio histologico mostro una neoplasia bien delimitada de estroma mixoide, con celularidad fusiforme sin atipia ni mitosis. La expresion inmunohistoquimica de MUC4, junto con el estudio de biologia molecular que detecto la expresion del gen de fusion FUS-CREB3L2, confirmaron el diagnostico de sarcoma …
Rabdomiosarcoma alveolar. Dos casos negativos para la fusión PAX3-FOXO1 y PAX7-FOXO1
Resumen Los rabdomiosarcomas son los tumores de partes blandas mas frecuentes en la edad pediatrica y en adultos jovenes. Morfologicamente se distinguen dos subtipos principales: el rabdomiosarcoma alveolar y el rabdomiosarcoma embrionario. El subtipo alveolar se asocia generalmente con un peor pronostico y presenta una fusion genica caracteristica que clasicamente se ha utilizado para confirmar el diagnostico: PAX3/7-FOXO1. Presentamos dos casos que fueron remitidos a nuestro centro. Ambos mostraron morfologia alveolar clasica y diferenciacion muscular basada en la inmunohistoquimica; no obstante, carecian de la fusion caracteristica PAX3/7-FOXO1. El objetivo de este articulo es resaltar l…
Primary cutaneous biphasic sarcomatoid basal cell carcinoma with myoepithelial carcinoma differentiation: A new variant
Isolated cases of basal cell carcinoma (BCC) with partial myoepithelial component have been described. However, myoepithelial differentiation has not been described in sarcomatoid basal cell carcinomas, which usually show features resembling osteosarcoma, chondrosarcoma, or leiomyosarcoma. We report a case of an 87-year-old man with a forehead lesion that histologically showed a minor component of conventional nodular BCC in transition with a major biphasic sarcomatoid growth composed of invasive spindle-cell and epithelial-like components, the latter with a reticular pattern and scattered ductal structures. Both components showed cytological atypia and high mitotic rate (26/10HPF), with at…
The Amount of Melanin Influences p16 Loss in Spitzoid Melanocytic Lesions: Correlation With CDKN2A Status by FISH and MLPA.
AIMS The risk assessment of spitzoid lesions is one of the most difficult challenges in dermatopathology practice. In this regard, the loss of p16 expression and the homozygous deletion of CDKN2A, have been pointed in the literature as reliable indicators of high risk. However, these findings are poorly reproducible, and the molecular bases underlying the loss of p16 expression remain unclear. We aimed to identify the underlying events causing loss of CDKN2A/p16 in spitzoid tumors. MATERIALS AND METHODS We evaluated the immunohistochemical expression of p16, and the presence of CDKN2A genetic alterations detected through fluorescence in situ hybridization (FISH) and multiplex ligation-depen…
Extra-Adrenal Adult Neuroblastoma With Aberrant Germ Cell Marker Expression: Maturation After Chemotherapy as an Important Clue to a Challenging Diagnosis
Adult neuroblastoma is an extremely infrequent neoplasm, usually occurring in the adrenal medulla or in the paraspinal sympathetic ganglia, as its childhood counterpart. We report a very unusual case of a Schwannian stroma-poor adult neuroblastoma of inguinal location, showing aberrant expression of germ cell markers: SALL4 and OCT4. This aberrant marker expression, the unusual positivity for NKX2.2 and the very scattered (instead of diffuse strong) PHOX2B expression, complicated the initial diagnosis. In this case, the posttreatment histological evaluation revealed the neuroblastic nature of the lesion. Neuroblastoma maturation after treatment is an unusual finding in adults, and in this …
Differential diagnosis of myxoid soft tissue tumors. Experience in the Clinical University Hospital of Valencia.
Abstract Soft tissue tumors with myxoid components are often a diagnostic challenge for the pathologist. We retrospectively reviewed 41 cases of soft tissue tumors with myxoid components diagnosed in our center over a five-year period. The most frequent diagnoses were myxofibrosarcoma and myxoid liposarcoma, followed by low-grade fibromyxoid sarcoma, low-grade fibromyxoid tumor and myxoid neurofibroma. Other diagnoses included were extraskeletal myxoid chondrosarcoma, myxoinflammatory fibroblastic sarcoma, low-grade myxoliposarcoma, myofibrosarcoma, fibromatosis, solitary fibrous tumor, non-ossifying variant of ossifying fibromyxoid tumor and ancient neurinoma with myxoid degeneration. Immu…
Cutaneous Lymphadenoma Is a Distinct Trichoblastoma-like Lymphoepithelial Tumor With Diffuse Androgen Receptor Immunoreactivity, Notch1 Ligand in Reed-Sternberg-like Cells, and Common EGFR Somatic Mutations.
The term "cutaneous lymphadenoma" was coined in this journal for an unusual lymphoepithelial cutaneous adnexal neoplasm, possibly with immature pilosebaceous differentiation. Some authors further proposed that cutaneous lymphadenoma was an adamantinoid trichoblastoma. However, although a hair follicle differentiation is widely accepted, the fact that this is a lymphoepithelial tumor is not appropriately explained by the trichoblastoma hypothesis. Our goal was to further clarify the phenotypic and genotypic features of cutaneous lymphadenoma in a series of 11 cases. Histologically, a lobular architecture surrounded by a dense fibrous stroma was present in all cases. The lobules were composed…