The pineal gland is a small midline structure in the brain responsible for melatonin secretion. Several types of tumors can arise from it; one group being the primitive neuroectodermal tumor (PNET), including the pineoblastomas. They are formed by pinealocytes and their precursor cells [1]. They are extremely malignant, and poorly differentiated in comparison to other pineal gland tumors, hence they are classified as grade IV tumors by the World Health Organisation (WHO).

Pineoblastomas are rare, and their etiology is still unknown. They constitute up to 50% of all malignancies that arise from the pineal parenchyma, yet they make up only 0.1% of all central nervous system (CNS) tumors [2] [3]. They primarily affect children, with similar incidence rates between females and males [4]. The occurrence of pineoblastomas is common in individuals with hereditary retinoblastomas [1] [5]. Most cases are thought to be sporadic, however, there are a minority of cases where a link to genetic mutations has been suggested, for example, mutations in the adenomatous polyposis coli (APC) or retinoblastoma (RB1) genes [4] [6]. The former has been associated with the increased likelihood of growth of the brain and gastrointestinal tract (GIT) tumors, while the latter is a risk factor for retinoblastomas [4] [7]. Familial cases have also been recorded in the literature [8].

Clinically, patients usually present with obstructive hydrocephalus. This is the result of the mass effect that the tumors have on surrounding structures, such as the cerebral aqueduct, as pineoblastomas tend to be large. Some children may present with signs and symptoms of Parinaud syndrome, which is the outcome of compression of the tectal plate.

CNS spread of the tumors is common, as they have a propensity to metastasize via the cerebral spinal fluid (CSF). This phenomenon precedes the diagnosis of pineoblastoma in about 15% of patients. The prognosis or pineoblastomas is poor, and this may be partly due to their locally invasive nature, or to their tendency to metastasize. The 5-year survival rate is estimated to be around 58%.

• Soft Tissue Mass

  tissue mass in the region of the pineal gland with eccentric calcification (anterior) and evidence of hydrocephalus. [21] Pre-contrast CT scan demonstrating moderate internal obstructive hydrocephalus, due to a large, partially calcified, dense mass [wikidoc.org]

  • Soft tissue mass lesion measureing2.9 X 2.7 X 2.7 cm • Hypointense T1,hyperintense T2 / FLAIR signal & homogenous post-contrast enhancement • Lesion is compressing the superior portion of the cerebral aqueduct with moderate supratentorial hydrocephalus [slideshare.net]

• Long Arm

  Chromosomal analysis of cultured cells from the tumor of a 10-week-old white male revealed an interstitial deletion of the long arm of chromosome 11, del(11)(q13.1q13.5). [ncbi.nlm.nih.gov]

• Short Arm

  The short arm was involved in two of the three cases; in the third case, the anomaly was in the long arm. Two cases showed unbalanced gain of chromosome 17q, one of them showing i(17)(q10). [ncbi.nlm.nih.gov]

• Incontinence

  Pain in the lower extremities and urinary incontinence with paraplegia improved during irradiation of the spinal cord after two courses of PVB therapy administered during a period of 6 weeks. [ncbi.nlm.nih.gov]

  Side Effect (1-6 months after Treatment) • Skin Burns • Hair Loss • Fatigue • Occasional Worsening of Neurological Symptoms • Headaches • Nausea / Vomiting • Hearing Loss • Dry Eyes • Late Side Effects (6-24 months after Treatment) • Ataxia, • Urinary Incontinence [slideshare.net]

• Urinary Incontinence

  Pain in the lower extremities and urinary incontinence with paraplegia improved during irradiation of the spinal cord after two courses of PVB therapy administered during a period of 6 weeks. [ncbi.nlm.nih.gov]

  Incontinence • Hearing Loss • Dry Eyes • Endocrine Disorders • 10-20% risk of cognitive change, which include memory loss and apathy 58. [slideshare.net]

• Headache

  We present the very rare case of a pineoblastoma with large central cyst in a 7-year-old boy who presented with a short history of gradually worsening headache and upward gaze palsy. [ncbi.nlm.nih.gov]

• Nystagmus

  […] such as the one in this case commonly present with the signs and symptoms of obstructive hydrocephalus and/or Parinaud's syndrome which is characterized by the following: upward gaze paralysis, normal vertical eye movement with doll's head maneuver, nystagmus [path.upmc.edu]

  Also noted were a right exotropia of 10 and nystagmus. Fixation was poor with the right eye. Nasal retinal traction, but no apparent mass, was noted. [healio.com]

  […] pineoblastoma include: [13] [16] HEENT Bulging soft spots ( fontanelles ) Eyes that are constantly looking down ( sunsetting sign ) Deficiency in upward-gaze Pupillary light-near dissociation (pupils respond to near stimuli but not light) Convergence-retraction nystagmus [wikidoc.org]

• Apathy

  Headaches • Nausea / Vomiting • Hearing Loss • Dry Eyes • Late Side Effects (6-24 months after Treatment) • Ataxia, • Urinary Incontinence • Hearing Loss • Dry Eyes • Endocrine Disorders • 10-20% risk of cognitive change, which include memory loss and apathy [slideshare.net]

The diagnosis of pineoblastomas incorporates medical imaging, laboratory analysis of specimens, as well as the clinical presentation. Macroscopically, the tumors appear as poorly defined lesions containing necrotic tissue and numerous bleeds. Microscopically, they consist of small, undifferentiated blue cells that often have no identifiable pattern, but display Homer Wright or Flexner-Wintersteiner rosette patterns in some instances [2]. Screening for CNS metastases is routine in many cases [2].

Imaging techniques play a role in differentiating pineoblastomas from other pineal gland neoplasms. The modalities employed are:

• Computerized tomography (CT) scanning: This often shows a hyperdense mass, poorly demarcated, with visible calcifications.
• Magnetic resonance imaging (MRI): Typically, the invasion of adjacent structures by an isointense or hypointense mass is visualized [5].

1. de Jong MC, Kors WA, de Graaf P, Castelijns JA, Moll AC, Kivelä T. The Incidence of Trilateral Retinoblastoma: A Systematic Review and Meta-Analysis. Am J Ophthalmol. 2015;160(6):1116-1126.e5
2. Dumrongpisutikul N, Intrapiromkul J, Yousem DM. Distinguishing between germinomas and pineal cell tumors on MR imaging. AJNR Am J Neuroradiol. 2012;33(3):550-555.
3. Lee JY, Wakabayashi T, Yoshida J. Management and survival of pineoblastoma: an analysis of 34 adults from the brain tumor registry of Japan. Neurol Med Chir (Tokyo). 2005;45(3):132-141; discussion 141-142.
4. Li MH, Bouffet E, Hawkins CE, Squire JA, Huang A. Molecular genetics of supratentorial primitive neuroectodermal tumors and pineoblastoma. Neurosurg Focus. 2005;19(5):E3.
5. Rodjan F, de Graaf P, Moll AC, et al. Brain abnormalities on MR imaging in patients with retinoblastoma. AJNR Am J Neuroradiol. 2010;31(8):1385-1389.
6. Wong FL, Boice JD Jr, Abramson DH, et al. Cancer incidence after retinoblastoma. Radiation dose and sarcoma risk. JAMA. 1997;278(15):1262-1267.
7. Ikeda J, Sawamura Y, van Meir EG. Pineoblastoma presenting in familial adenomatous polyposis (FAP): random association, FAP variant or Turcot syndrome? Br J Neurosurg. 1998;12(6):576-578.
8. Lesnick JE, Chayt KJ, Bruce DA, et al. Familial pineoblastoma. Report of two cases. J Neurosurg. 1985; 62(6):930-932.