Atypical and aggressive diffuse leptomeningeal glioneuronal tumor in a young adult: A case report and review of the literature

Abstract

Background: DLGNT is a rare tumor, commonly diagnosed in pediatric age; in most cases, the pathology presents a slow and indolent evolution. We present a case report of a young adult affected by DLGNT characterized by aggressive and atypical behavior. Case Description: A 21-year-old male presented with mild paraparesis and hypoesthesia with a D2 level. MRI scan of the brain and spine showed a dorsal intramedullary lesion; a diffuse craniospinal leptomeningeal thickening was also present. After a week, the neurological status deteriorated rapidly with paraparesis worsening and onset of acute hydrocephalus. The patient underwent external ventricular drain positioning; a C7-D4 laminectomy was subsequently performed with partial tumor resection. Histological examination revealed a DLGNT with aggressive aspects (Ki67 30%). Postoperatively, the patient showed an immediate mild worsening of the lower limbs deficit. After a few days, severe further neurological deterioration occurred with progressive motor deficit to the upper limbs and ultimately respiratory failure. Mechanical ventilation was necessary and the patient was transferred to the ICU; during the following weeks, he developed tetraplegia and underwent ventriculoperitoneal shunt positioning. By the time, the histological diagnosis was available, the clinical status would not allow radiotherapy or chemotherapy. The patient deceased approximately 90 days after hospitalization due to respiratory complications. Conclusion: DLGNT is a rare tumor; diagnosis requires a high index of suspicion and confirmation with biopsy. Although most cases have an indolent course, some patients may have aggressive forms. High proliferation index, hydrocephalus occurrence, and massive craniospinal leptomeningeal spread appear to be associated with worse prognosis.

Aggressive Diffuse Leptomeningeal Glioneuronal Tumor in a Pediatric Patient Presenting With Mismatch Repair Gene Mutations

“…Children are most commonly affected by DLGNT, with the frequently being twice males [ 5 , 7 ]. Clinical presentation can be variable because of its extremely low incidence.…”

“…Symptoms can vary depending on the rate at which the tumor is growing and the specific neural structures involved. Radiological imaging can demonstrate leptomeningeal enhancement, discrete intramedullary spinal masses, communicating hydrocephalus, or combinations of these findings [ 5 ]. DLGNT can be misdiagnosed for infectious or inflammatory pathologies [ 8 ].…”

“…A WHO grade has yet to be assigned. In most cases, the tumor behaves like a low-grade tumor with prolonged overall survival; however, several cases with aggressive clinical courses have been described [ 5 ]. Existing reports are insufficient to develop adequate management guidelines and establish prognostic factors [ 5 ].…”

“…DLGNT is usually diagnosed in children, although adult cases have also been reported [ 5 ]. The clinical presentation of DLGNT is often nonspecific, which may include symptoms of hydrocephalus, spinal cord compression, and seizures.…”

“…The clinical presentation of DLGNT is often nonspecific, which may include symptoms of hydrocephalus, spinal cord compression, and seizures. Signs and symptoms related to hydrocephalus are the most common clinical onset presentation [ 5 ]. Communicating hydrocephalus is secondary to the high protein content of the cerebrospinal fluid (CSF), creating an absorption deficiency [ 6 ].…”