RESUMO
Background: "Ping-pong" fractures are a type of depressed fracture in which there is no rupture of the inner or outer table of the skull. It is produced by incomplete bone mineralization. Its appearance is frequent during neonatal and infant ages and is extremely rare outside of these age periods. The objective of this article is to present the case of a 16-year-old patient who presented a "ping-pong" fracture after a traumatic brain injury (TBI) and discuss the underlying physiopathogenesis of these types of fractures. Case Description: A 16-year-old patient presented to the emergency department with a TBI, referring headaches and nausea. Non-contrast brain computed tomography displayed a left parietal "ping-pong" fracture. Laboratory tests showed hypocalcemia, subsequently diagnosing hypoparathyroidism. The patient remained under observation for 48 h. He was managed conservatively and started on calcium carbonate and vitamin D supplements with a favorable evolution. Hospital discharge was granted with TBI discharge instructions and warning signs. Conclusion: The age of presentation of our case was atypical, according to the reported literature. When faced with a "ping-pong" fracture outside of an early age, underlying bone pathologies must be ruled out, which could potentially generate incomplete bone mineralization of the skull.
RESUMO
Background: Renal cell carcinoma (RCC) represents 1% of all cancers and its brain metastases amount to 8.1% of all metastatic tumors. Late brain metastases are defined as tumors that appear 10 years after diagnosis of the primary lesion. The objective of this work is to discuss which biological pathways are responsible for the late appearance of these metastases analyzing eight cases. Case Description: We report here eight cases of late brain metastases of RCC treated between 2018 and 2021. Patients consulted for different clinical complaints. Brain magnetic resonance imaging and computed tomography scan were performed on all patients. They were treated by complete surgical resection plus radiosurgery or by radiosurgery alone. The histology of most metastases showed clear cell RCC. Conclusion: In the presence of a patient with an intracranial tumor and a history of RCC with more than 10 years of evolution, the presence of late metastasis should always be considered. There are many theories described in the literature that try to explain the late appearance of brain metastases from RCC (low mitotic index, impaired immune system, cross talk, self-seeding, and among others).