Relation Between Atypical Fibroxanthoma and Pleomorphic Dermal Sarcoma: Histopathologic Features and Review of the Literature. / Relación entre fibroxantoma atípico y sarcoma pleomórfico dérmico: histopatología de ambos y revisión de la literatura.

The relation between atypical fibroxanthoma and pleomorphic dermal sarcoma has led to confusion and debate in the literature. Both tumors present on sun-exposed skin, typically on the head and neck, in patients of advanced age. Both are comprised of a variable mix of histiocytoid, spindle, epithelioid, and/or giant multinucleated cells with pleomorphic nuclei. No immunohistochemical diagnostic techniques have emerged to distinguish these tumors. Diagnosis is by exclusion. Histologically, atypical fibroxanthoma is seen as a well-circumscribed dermal nodule but there will be no evidence of extensive subcutaneous invasion, tumor necrosis, or lymphovascular or perineural invasion. Therefore, if any of the aforementioned features is present, the diagnosis would be pleomorphic dermal sarcoma. This narrative review of the literature aims to identify the distinguishing and overlapping histopathologic features of these 2 tumors as they have been described in case series.

Parathyroid gland hyperplasia associated with tuberculous granulomatous inflammation manifesting as primary hyperparathyroidism.

OBJECTIVES: Inflammatory disorders of the parathyroid gland are poorly defined. Only seven cases of granulomatous infection have been reported in the literature. PATIENTS AND METHODS: A 68-year-old woman presented with parathyroid hormone level at 277pg/mL and calcium level at 10.8mg/dL, considered as primary hyperparathyroidism. Parathyroidectomy was performed, normalizing analytical values. RESULTS: Normal-size gland with chief cell hyperplasia, focal pseudofollicular changes, and presence of epithelioid granulomas with Langhans giant cells and caseous necrosis areas, and a positive PCR for M. tuberculosis complex was identified. Chronic granulomatous inflammation could provoke a cascade of immune system activation, resulting in hyperplasia with the consequent increase in parathyroid function, and therefore primary hyperparathyroidism. CONCLUSIONS: In populations with a high incidence of tuberculosis, the coexistence of these pathologies must be kept in mind. This theory needs further biomolecular studies to be confirmed, but it provides a new perspective within the possible etiologies of hyperparathyroidism.

Relación entre fibroxantoma atípico y sarcoma pleomórfico dérmico: histopatología de ambos y revisión de la literatura / Relation Between Atypical Fibroxanthoma and Pleomorphic Dermal Sarcoma: Histopathologic Features and Review of the Literature

La relación entre el fibroxantoma atípico (FXA) y el sarcoma pleomórfico dérmico (SPD) ha sido confusa y objeto de debate a lo largo de los años en la literatura científica. Son tumores que se presentan en pacientes de edad avanzada en piel fotoexpuesta, típicamente cabeza y el cuello. Están formados por una mezcla variable de células histiocitoides, fusiformes, epitelioides y gigantes multinucleadas con núcleos pleomórficos. No existen técnicas inmunohistoquímicas diagnósticas de estas entidades y su diagnóstico debe ser de exclusión. El FXA es una neoplasia dérmica, bien delimitada, con ausencia de infiltración difusa de tejido subcutáneo, necrosis tumoral o invasión linfovascular o perineural. Estando alguna de las características anteriores presente, debe hacerse el diagnóstico de SPD. En esta revisión narrativa de la literatura intentaremos determinar cuáles son las características histopatológicas precisas de ambas entidades, según las series publicadas en la literatura y aquellos aspectos que las diferencian o relacionan (AU)

The relation between atypical fibroxanthoma and pleomorphic dermal sarcoma has led to confusion and debate in the literature. Both tumors present on sun-exposed skin, typically on the head and neck, in patients of advanced age. Both are comprised of a variable mix of histiocytoid, spindle, epithelioid, and/or giant multinucleated cells with pleomorphic nuclei. No immunohistochemical diagnostic techniques have emerged to distinguish these tumors. Diagnosis is by exclusion. Histologically, atypical fibroxanthoma is seen as a well-circumscribed dermal nodule but there will be no evidence of extensive subcutaneous invasion, tumor necrosis, or lymphovascular or perineural invasion. Therefore, if any of the aforementioned features is present, the diagnosis would be pleomorphic dermal sarcoma. This narrative review of the literature aims to identify the distinguishing and overlapping histopathologic features of these 2 tumors as they have been described in case series (AU)