Hamartoma fibroso de la infancia: una serie de 21 casos y revisión de la literatura

Abstract

Resumen: Introducción: El hamartoma fibroso de la infancia (HFI) es tumor poco frecuente de tejidos blandos en lactantes y niños, caracterizado histopatólogicamente por su morfología trifásica y curso benigno. Métodos: Presentamos las características histopatológicas e inmunohistoquímicas de una serie de 21 casos de HFI y revisamos sus principales diagnósticos diferenciales. Resultados: Las lesiones predominaron en varones con una edad media de 3,7 años (5 meses-24 años) en localizaciones previamente descritas. Histopatológicamente, se caracterizaron por proporciones variables de tejido fibroblástico, mesenquimal y adiposo maduro. Tres casos (21%) mostraron zonas hialinizadas con artefactos en grietas, que imitaban al fibroblastoma de células gigantes. Presentaron tinción positiva para actina de músculo liso 8/13 (61%) en el componente fibroblástico, CD34 en 6/8 (75%) en el mesenquimal inmaduro y fibroblástico; y S100 en el tejido adiposo en 7/7 (100%). Conclusión: Nuestros hallazgos histopatológicos son superponibles a los descritos en series amplias. No obstante, la heterogeneidad clínica obliga a conocer las variantes de esta entidad dentro de su típica histomorfología trifásica, para lograr un correcto diagnóstico y manejo terapéutico. Abstract: Background: Fibrous hamartoma of infancy (FHI) is a rare soft-tissue tumor usually seen in infants and young children. Histologically, the tumor is characterized by a triphasic morphology, and the clinical course is benign. Methods: We described the histopathologic and immunohistochemical features in a series of 21 cases of FHI and reviewed the main entities to consider in differential diagnosis. Results: Most patients in the series were male. The mean age was 3.7 years (range, 5 months–24 years), and lesions were found in locations that have been previously reported. Histopathologically, the tumors were composed of variable proportions of fibroblastic, mesenchymal, and mature adipose tissue. Three of the 13 immunohistochemically stained biopsies (14%) contained hyalinized zones with cracking artifacts, mimicking giant cell fibroblastoma. Eight of the 13 stained with smooth-muscle actin (61%) were positive in the fibroblastic component, 6 of the 8 stained with CD34 (75%) were positive in the immature mesenchymal and fibroblastic components, and all 7 stained with S100 were positive (100%) in adipose tissue. Conclusions: Our histopathologic findings are consistent with those described in larger series. However, in order to reach a precise diagnosis and plan treatment, clinical heterogeneity obliges us to become familiar with variations in the characteristic triphasic histology of FHI.

Keywords

• Fibrous hamartoma of the infancy
• Connective tissue
• Fibrous tissue
• Pediatric tumors