Peer Reviewed

Photoclinic

Pilocytic Astrocytoma

Volume 58 - Issue 10 - October 2018

Authors:
Syed A. A. Rizvi, PhD, MS, MBA
Hampton University School of Pharmacy, Hampton, Virginia

Zafar Qureshi, MD
UHI CommunityCare Clinic, Miami, Florida

Citation:
Rizvi SAA, Qureshi Z. Pilocytic astrocytoma. Consultant. 2018;58(10):283-284.

 

An 11-year-old girl presented to the clinic with concern for worsening vision and daily headaches for the past 6 months, which were located diffusely and mildly relieved with ibuprofen. She also reported having nausea and vomiting.

Physical examination. On examination, the patient was alert, awake, and talking. She was normocephalic without obvious head abnormality. Her pupils were equal and reactive to light and accommodation. Neurologic examination revealed no gross deficit, appropriate interaction for her age, and good motor strength, with no apparent abnormalities in function of cranial nerves II through XII. Findings of examinations of the heart, lungs, abdomen, extremities were normal. The patient’s temperature was 37°C, her blood pressure was 104/77 mm Hg, her pulse was 86 beats/min, and her respiratory rate was 20 breaths/min. Her height was 140 cm and her weight was 32 kg.

Diagnostic tests. Laboratory test results included the following: hemoglobin, 10.8 g/dL (reference range, 11.5-15.5 g/dL); sodium, 134 mEq/L (reference range, 135-146 mEq/L); potassium, 5.3 mEq/L (reference range, 3.8-5.1 mEq/L); albumin, 3.3 g/dL (reference range, 3.6-5.1 g/dL), and glucose, 69 mg/dL (reference range, 65-99 mg/dL).

Given her headaches and worsening vision, computed tomography (CT) scans of the head were obtained, the results of which showed a brain mass, and the patient was sent to the emergency department, where further tests (including magnetic resonance imaging [MRI]) were done.

The MRI with contrast showed a large, 4.8 × 4.4 × 3.5-cm, mildly hyperintense, lobular lesion in the third ventricle and left foramen of Monro (Figure 1). The growth pattern appeared to be predominantly noninfiltrative, although parenchymal infiltration was present in some areas. Molecular testing for BRAF mutations on the resected tumor reveled a duplication at 7q34 and KIAA1549-BRAF fusion, findings consistent with sporadic pilocytic astrocytoma (PA).

astrocytoma 1
Figure 1. Preoperative T1-weighted MRI showing a lobular lesion in the third ventricle and left foramen of Monro.

Histological, histochemical, and immunohistochemical studies eventually confirmed the diagnosis of PA, World Health Organization (WHO) grade I (the least aggressive type).

NEXT: Discussion and Outcomes of the Case

Discussion. PA is a benign glial tumor that predominantly affects children and arises most often in the cerebellum but can also occur near the brainstem, in the optic nerve, or in the hypothalamic region of the brain.1,2 The prognosis in young children (5-19 years) is excellent, with a 5-year survival rate of 96.5%, but that rate declines significantly with age to 52.9% among patients aged 60 or older.3 It also has been reported that patients with PA in the hypothalamus have a less favorable prognosis.4,5 The genetics of PA most commonly involves KIAA1549 and BRAF oncogenic fusion, and thus it has been used as a diagnostic marker.6-9

PAs are typically removed surgically. If complete resection is not possible, adjuvant therapy (chemotherapy and radiotherapy) can be used.10,11

Outcome of the case. Our patient underwent left craniotomy and resection of the intraventricular mass (Figure 2). Postoperatively, right-sided hemiplegia and a very slow verbal response were noted. Due to the location of the resection, she developed diabetes insipidus, panhypopituitarism, and cerebral salt-wasting syndrome and was closely monitored by endocrinologist. The patient is currently taking medications and undergoing physical therapy to address her symptoms and is in stable condition.

astrocytoma 2
Figure 2. Postoperative MRI showing no residual or recurrent tumor.

 

References:

  1. Sharifi G, Rahmanzadeh R, Lotfinia M, Rahmanzade R. Pilocytic astrocytoma of fornix mimicking a colloid cyst: report of 2 cases and review of the literature. World Neurosurg. 2018;109:31-35.
  2. Ohgaki H, Kleihues P. Population-based studies on incidence, survival rates, and genetic alterations in astrocytic and oligodendroglial gliomas. J Neuropathol Exp Neurol. 2005;64(6):479-489.
  3. Johnson DR, Brown PD, Galanis E, Hammack JE. Pilocytic astrocytoma survival in adults: analysis of the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. J Neurooncol. 2012;108(1):187-193.
  4. Colosimo C, Cerase A, Maira G. Regression after biopsy of a pilocytic opticochiasmatic astrocytoma in a young adult without neurofibromatosis. Neuroradiology. 2000;42(5):352-356.
  5. Koeller KK, Rushing EJ. From the archives of the AFIP: pilocytic astrocytoma: radiologic-pathologic correlation. Radiographics. 2004;24(6):1693-1708.
  6. Collins VP, Jones DTW, Giannini C. Pilocytic astrocytoma: pathology, molecular mechanisms and markers. Acta Neuropathol. 2015;129(6):775-788.
  7. Sadighi Z, Slopis J. Pilocytic astrocytoma: a disease with evolving molecular heterogeneity. J Child Neurol. 2013;28(5):625-632.
  8. Chourmouzi D, Papadopoulou E, Konstantinidis M, et al. Manifestations of pilocytic astrocytoma: a pictorial review. Insights Imaging. 2014;5(3):387-402.
  9. Rodriguez FJ, Lim KS, Bowers D, Eberhart CG. Pathological and molecular advances in pediatric low-grade astrocytoma. Annu Rev Pathol. 2013;8:361-379.
  10. Khan MA, Godil SS, Tabani H, Panju SA, Enam SA. Clinical review of pediatric pilocytic astrocytomas treated at a tertiary care hospital in Pakistan. Surg Neurol Int. 2012;3:90.
  11. Cinalli G, Aguirre DT, Mirone G, et al. Surgical treatment of thalamic tumors in children. J Neurosurg Pediatr. 2018;21(3):247-257.