By Dr. Laverne Rufaro Hamadziripi-Sober
Abstract:
CLINICAL DATA
A four-year-old female patient presented with a posterior fossa
tumour with a year history of postprandial vomiting,
headaches, partial vision loss and inability to walk. A biopsy
revealed it to be classic medulloblastoma. A VP shunt was
inserted and mass excision was performed to debulk the
tumour.
IMAGING AND PATHOLOGY
Post craniotomy, an MRI and CT scan revealed a residual
tumour measuring (1.6x 3.2 x 2.0) cm with no leptomeningeal
or spinal drop lesions. The patient was then referred for
chemo-radiotherapy. A CT scan was done for treatment
planning. The patient was positioned supine using a vacuum
bag, headrest, and beam-directional shell for immobilization,
ensuring precision during treatment. Whole-body images were
obtained with 5mm slices from vault of the skull to the bottom
of the sacrum, with 3mm slices throughout the primary tumour.
CLINICAL COURSE
3D-Conformal radiotherapy commenced one month
post-surgery and included craniospinal irradiation using 2
parallel opposed cranial fields and one direct posterior field to
the spine (23.4 Gy in 13 fractions) followed by a posterior fossa
boost (30.6 Gy in 17 fractions), totalling 54 Gy. Treatment
employed multi-leaf collimators and weekly field feathering to
optimize dose distribution and minimize toxicity.
Dexamethasone was used to cater for vasogenic oedema. The
patient was able to complete treatment without severe late
effects and with a single interruption. Reactions noted were
erythema, vasogenic oedema and fatigue, these resolved post
treatment and the patient since regained the ability to walk
DISCUSSION
The patient showed significant clinical improvement, including
regaining ability to walk, indicating effective tumour control,
neurological recovery and reduced treatment-toxicity. This
case shows the importance of timely, precise radiotherapy and supportive care in achieving favourable outcomes in
low-resource countries when treating paediatric brain tumours