Posterior fossa tumors (PFTs) are prevalent in children, and about half of all childhood brain tumors arise from the structures of the posterior fossa. Studies on PFTs in Iranian children have mainly focused on epidemiological characteristics. This study aimed to evaluate surgical outcomes and predictive factors for survival in children with PFTs in Shiraz, Iran. A prospective cohort study was conducted from March 2014 to September 2019 in Namazi Hospital affiliated with Shiraz University of Medical Sciences (Shiraz, Iran). A total of 87 pediatric patients under the age of 16 who were diagnosed with PFT and had undergone surgery were recruited. The children were followed up for postoperative outcomes such as mortality and neurological complications. Data were analyzed using SPSS software (version 20.0) and R software (version 3.3.1). P<0.05 was considered statistically significant. The mean age of the patients was 6.49±4.14 years and 64.4% were male. Sixteen patients were lost to follow-up, 31 died after surgery, and 40 were in remission during phone calls. The median survival time of the patients was four years. The most common type of PFT was medulloblastoma (n=46, 53%). The result of the multivariate Cox proportional hazards model showed that age (P=0.034) was correlated with postoperative survival, hazard ratio 0.90 (95% confidence interval 0.82 to 0.99). Among various predictive factors, lower age was associated with poor outcomes in pediatric children with PFTs.

Intracranial inflammatory pseudotumors (IIPT) are one of the differential diagnosis for the central nervous system (CNS) tumors. They represent a rare condition that may mimic clinically and radiologically intracranial tumors and induce their complications. Among their etiologies, neurosarcoidosis is one of the less known and less frequent. To the best of our knowledge, only two cases of posterior fossa IIPT have been reported in the literature. We present here the 3rd case related to a neurosarcoidosis.

We report the case of a 55-year-old female patient who presented with an altered state of consciousness associated to severe intracranial hypertension syndrome for four months. Glasgow coma scale on admission was 14/15. Brain imaging revealed bilateral cerebellar micronodular meningeal enhancement regarding the mesencephalon and the pons, as well as a nodular lesion of the 4th ventricle causing a triventricular acute hydrocephalus. The patient had a ventriculo-peritoneal shunt with a favorable outcome. Afterwards, she underwent a salivary gland biopsy which confirmed the diagnosis of neurosarcoidosis.

Posterior fossa IIPT are very rare, mainly when located in the posterior fossa, leading to confusion with other pathologies. MRI has an important role in the diagnosis of these lesions, and the determination of their etiology. It shows other than the IIPT itself, many other signs such as leptomeningeal enhancement, nodular lesions or pituitary stalk thickening. These signs can orientate towards the diagnosis. Treatment may associate to symptomatic approach, corticosteroids. Surgical resection may be proposed when the diagnosis remains doubtful.