Primary intracranial peripheral primitive neuroectodermal tumor: lessons from an exceptionally rare neoplasm. Illustrative case.

BACKGROUND: The primary intracranial peripheral primitive neuroectodermal tumor (pPNET) is a lesion subtype within the Ewing sarcoma family of tumors. pPNETs are extremely uncommon pathologies, accounting for 0.03% of intracranial tumors and 1% to 2% of Ewing sarcoma cases. Given its histological aspect similar to other highly proliferative malignant neuroectodermal neoplasms, pPNET merits extensive workup for accurate diagnosis and treatment. OBSERVATIONS: A 36-year-old male presented to the emergency department with a 1-year history of headaches in the right frontoparietal area, generalized tonic-clonic seizures, and a history of the resection of a tumor labeled as a meningioma 5 years before admission. He was neurologically intact. Brain magnetic resonance imaging revealed a heterogeneous focal lesion of 25 × 35 × 23 mm with a necrotic center and neoformative appearance in the right frontal cortex. The patient underwent multimodal treatment with gross-total resection, radiotherapy, and chemotherapy. Histopathological examination results supported the diagnosis of pPNET. At the 2-year follow-up, the patient had no new-onset symptoms, and brain imaging revealed absent signs of tumor recurrence. LESSONS: The present case describes an extraordinary pPNET case, initially confounded as a clear cell meningioma. Managing pPNET requires thorough investigation, careful differentiation from similar neuroectodermal lesions, and multimodal treatment to improve the patient's prognosis.

Modelo predictivo de la no unión de tibia / Tibia non union predictive model

OBJETIVOS: Estimar un modelo predictivo para la no-unión en pacientes que presentan fractura de tibia. MATERIALES Y MÉTODOS: Estudio de cohorte retrospectivo, en pacientes con fractura de tibia operadas entre 2012 y 2018, con un mínimo de 12 meses de seguimiento, excluyendo amputaciones traumáticas. Realizamos un modelo de regresión logística con 13 variables descritas en la literatura. Se descartaron las variables estadísticamente no significativas y las que no causaban efecto de confusión. Se evaluó la bondad de ajuste mediante el test de Hosmer-Lemeshow y la discriminación del modelo con la curva ROC. RESULTADOS: Se incluyeron 411 fracturas de tibia, las variables estadísticamente significativas fueron: exposición ósea OR » 2,57(IC:1,15­5,75, p » 0,022), diabetes OR » 3,29 (IC:1,37­7,91, p » 0,008) y uso de tutor externo OR » 1,77(IC:0,81­3,85), el que tuvo efecto de confusión. La bondad de ajuste demostró que los datos se ajustan adecuadamente al modelo (p » 0,35). La curva ROC demuestra un 70,91% de poder discriminatorio. Al evaluar aisladamente las fracturas expuestas, no hubo asociación estadísticamente significativa con ninguna variable. DISCUSIÓN: Al evaluar el modelo, obtuvimos una asociación estadísticamente significativa entre: no unión, exposición ósea, diabetes y uso de tutor externo, información concordante con la literatura. Al estudiar el subgrupo de fracturas expuestas, las demás variables son estadísticamente no significativas. Eso refleja que la exposición ósea es la variable que confiere mayor riesgo. El seguimiento adecuado de esos pacientes es fundamental dado este alto riesgo de evolucionar con no-unión. CONCLUSIÓN: En nuestra serie, la exposición ósea es el factor de riesgo más importante para presentar no unión de tibia.

OBJECTIVES: Estimate a predictive model for non-union in patients presenting with a tibial fracture. MATERIALS AND METHODS: Retrospective cohort study in patients with tibia fractures operated between 2012 and 2018, with a minimum follow-up of 12 months, excluding traumatic amputations. We performed a multivariate logistic regression model with 13 variables described in the literature. The variables that were statistically non-significant and those variables that do not cause confusion, were discarded. Goodness of fit was evaluated using the Hosmer-Lemeshow test and the discrimination of the model with the ROC curve. RESULTS: 411 tibial fractures were included, the statistically significant variables were: bone exposure OR » 2.57(CI:1.15­5.75, p » 0.022), diabetes OR » 3.29(CI:1.37­7.91, p » 0.008) and use of external fixation OR » 1.77(CI:0.81­3.85), being included in the model because of its confounding effect. Goodness of fit demonstrates that the data fit the model adequately(p » 0.35). The ROC curve demonstrates 70.91% discriminatory power. When evaluating the exposed fractures in isolation, there was no statistically significant association with any variable. DISCUSSION: When evaluating the model, we obtained a statistically significant association between non-union, bone exposure, diabetes and use of external fixation, being consistent with the literature. When studying the subset of exposed fractures, the other variables are statistically non-significant. This reflects that bone exposure is the variable that confers the greatest risk. Proper follow-up of these patients is essential given this high risk of evolving with non-union. CONCLUSION: In our series, bone exposure is the most important risk factor for presenting tibial non-union.

Pilomatricoma como diagnóstico diferencial de adenitis cervical granulomatosa

El niño con una masa cervical representa un desafío para el pediatra. Lo más frecuente en niños son los procesos benignos de origen infeccioso. Presentamos un niño con tumoración laterocervical posterior con diagnóstico de pilomatricoma, tumor benigno poco conocido en Pediatría . No presenta características específicas, por lo que su diagnóstico se base en el estudio de anatomía patológica. El único tratamiento posible es la exéresis completa. El pilomatricoma se debe incluir en el diagnóstico diferencial de adenitis cervical en niños para evitar intervenciones y tratamientos innecesarios.

Children with neck masses are an everyday challenge for pediatricians. Infectious diseases are the most common etiology in childhood. We report a child with a neck mass who was diagnosed with pilomatrixoma. It is a quite unknown benign skin tumor in pediatrics. It cannot be easily differentiated from other skin tumors, and biopsy is necessary to make the definitive diagnosis. Treatment of pilomatrixoma consists of total surgical excision. Pilomatrixoma should be considered in the differential diagnosis of cervical lymphadenitis in children to avoid unnecessary interventions and antibiotic treatment.