Case Report
A 12 year-old male, previously fit and well, presented with a 2-week
history of headache, nausea, vomiting, ataxia and drowsiness. A head CT
scan showed a homogenous enhancing lobulated lesion within the right
thalamic/pineal region which extended inferiorly to the right midbrain.
The head and spine magnetic resonance (MR) examination demonstrated a
lobular mass which appeared to be extra-axial and in continuity with the
pineal gland with no evidence of disease involvement of the spine
(Figure 1). Testicular ultrasound was normal. Serum alpha-fetoprotein
(AFP) was 1,832 ng/ml and serum beta-human chorionic gonadotropin
(β-HCG) was 16 IU/L. Cerebrospinal fluid (CSF) cytology did not show any
malignant cells and AFP in CSF was 34.9 ng/ml (β-HCG not available).
The child underwent endoscopic third ventriculostomy, stereotactic
biopsy of the posterior third ventricular lesion, and insertion of a
Rickham reservoir. The initial biopsy was inconclusive. A second biopsy
was obtained together with insertion of an external ventricular drain,
which was later replaced by a ventriculo-peritoneal shunt. The second
biopsy showed a malignant GCT with predominant features of YST (Figure
2). Immunohistochemistry confirmed focal positivity with AFP,
pan-cytokeratin and in occasional cells with HCG. PLAP, synaptophysin
and GFAP were negative while INI1 (BAF47) was normally expressed in the
tumour cells. The tumour showed high proliferation index (Ki67: 70%).
The child was treated as per SIOP CNS GCT 96 protocol off-trial with 4
cycles of cisplatin, etoposide and ifosfamide (PEI). Following the
4th cycle of chemotherapy, MR assessment showed
partial response according to Response Evaluation Criteria in Solid
Tumors, version 1.114. Serum tumour markers also
normalized. Subsequently, he received radical volumetric modulated arc
therapy (VMAT) to the residual tumour (54 Gy in 30 fractions) with a
single arc VMAT plan. Following that, MR brain scan revealed a stable
subcentimetre tumour residuum with negative serum tumour markers.
Two years after the end of treatment, routine serum tumour markers
showed AFP 56.6 ng/ml with β-HCG <2 IU/L. MR brain and spine
demonstrated stable intracranial disease, with a new solitary plaque of
enhancing tissue over the surface of the spinal cord posteriorly on the
left side at the level of T10 disc space (Figure 1). The child received
alternating carboplatin/etoposide and ifosfamide/etoposide for a total
of 4 cycles as per SIOP CNS GCT II trial (NCT01424839). After 4 cycles
of chemotherapy, shrinkage of the T10 meningeal spinal metastasis was
seen on MRI; serum AFP was 4.8 ng/ml. He then received high dose
thiotepa and etoposide followed by autologous stem cell transplant
(ASCT). Finally, he received craniospinal irradiation CSI (30 Gy in 16
fractions) with a boost to the site of recurrence at T10 (20.8 Gy in 13
fractions).
The end of treatment MRI showed maintained response and serum AFP was
normal. This young man is currently alive, with normal serum tumour
markers and no evidence of further recurrence 5 years after completion
of treatment.