Pineal region tumours

• The pineal region is located in the midline between
• The tectum of the midbrain and
• The roof of the third ventricle.

• Pineal tumours are rare and are more commonly seen in children than adults.

• Modern neurosurgical and neuro-oncology management is determined by tumour type and includes biopsy, open surgery, fractionated radiotherapy, and chemotherapy.

• Most recent advances in the treatment of pineal tumours have mainly been driven by clinical trials in paediatric patients.

• During the late stages of intrauterine life and the early postnatal period, the human pineal gland consists primarily of cells arranged in rosettes similar to those of the developing retina.
• These feature abundant melanin pigment as well as cilia with a 9 + 0 microtubular pattern.

• By the age of 3 months, the number of pigmented cells gradually decreases so that pigment becomes undetectable by histochemical methods.
• As differentiation progresses, cells that are strongly immunoreactive for neuron-specific enolase accumulate.

• By the age of 1 year, pinealocytes predominate.

• To a variable extent, pineal parenchymal tumours mimic the developmental stages of the human pineal gland.

graph TD
    A[Pineal region tumor] --> B[Non-Germ cell tumor]
    A --> C[Germ cell tumor]

    B --> D[Adjacent tissue]
    B --> E[Pineal parenchymal]

    D --> F[Pineal cyst]
    D --> G[Tectal glioma]
    D --> H[Meningioma]
    D --> I[Other]

    E --> J[Pinocytoma]
    E --> K[Pinoblastoma]
    E --> L[Pineal parenchymal tumor of intermediate differentiation]
    E --> M[Papillary tumor of pineal region]

    C --> N[Non-germanomatous]
    C --> O[Germinoma]

    N --> P[Embryonal Origin]
    N --> Q[Non-Embryonal origin]

    P --> R[Teratoma]

    Q --> S["Trophoblast (choriocarcinoma)"]
    Q --> T["Yolk sac (AKA: endodermal sinus tumor)"]

    O --> U[Germinoma]

• Germ cell tumours (GCTs, 60%),

• Pineal parenchymal tumours (PPTs) (30%)

• Gliomas (5%)

• Rare
• Papillary tumour of the pineal region (PTPR),
• Ependymoma,
• Meningioma,
• Lymphoma, and
• Metastases

• Raised intracranial pressure (87%)

• Parinaud’s syndrome (76%) due to midbrain compression (restricted upgaze, loss of accommodation reflex, near-light dissociation, and convergence nystagmus) and

• Cerebellar signs (52%)

• Contrast-enhanced magnetic resonance imaging (MRI) of the brain and whole spine
• For
• HCP diagnosis
• Anatomy for surgical approaches,
• Presence of metastatic spread

• Serum and cerebrospinal fluid (CSF) sampling for tumour markers is also necessary.
• Elevated β human chorionic gonadotrophin (β-HCG) and α-fetoprotein (AFP) may be diagnostic for GCT subtype without the need for biopsy.

• Tissue biopsy
• By endoscopic, stereotactic, or open approach.

• ETV
• Prefered CSF diversion
• Allows biopsy of the tumour in the same operation.