An Evolution in the Use of Radiation

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Slide 1

Talk Outline

Overview of Germ Cell tumors

Case Presentation

Traditional Radiation Treatment for Germinoma

Alternate therapeutic Approaches

Chemotherapy alone (International study)

Reduced Field Radiation without Chemotherapy (Royal Marsden Lancet Review)

Combined Approaches

COG ACNS 0232

Slide 2

Overview of Germ Cell Tumors

Rare-2% of pediatric tumors in North America

Germinoma-60-70%

“Malignant” subtypes 15-20%

Embryonal, endodermal sinus, choriocarcinomas

Teratomas benign, immature and malignant 15-20%

Malignant-admixture of benign teratoma with one or more malignant germ cell lines

Slide 3

Overview of Germ Cell Tumors

Anatomy

occur in diencephalic structures-almost exclusively midline 3rd ventricle

Pineal region

Most Frequent 50-60%

Suprasellar

30-35%

Rare

Basal ganglia and thalamic nuclei

Multifocal – Pineal and suprasellar “multiple midline germinomas” 20%

Slide 4

Overview of Germ Cell Tumors

Epidemiology

Pineal germioma

Adolescent males

Suprasellar

First 2 decades no gender predilection

Teratomas

Teratomas-young children

“Malignant” histiotypes

Older childrem adolescent and young adults

Slide 5

Overview of Germ Cell Tumors

Presentation

Pineal tumors

Elevated intracranial pressure-compression of sylvian aquaduct

Parinaud’s syndrome-ocular symptoms of decrease upward gaze, near-light dissociation, diminished convergence

Suprasellar

Diabetes insipidus, precocious or delayed sexual development, visual deficits

Serum Markers

AFP-serum or CSF in embryonal, endodermal sinus or malignant teratoma-if posistive excludes a pure germinoma

Β-HCG- 10IU-70IU in 10-20% pure germinomas, >1000IU choriocarcinoma

Slide 6

Overview of Germ Cell Tumors

Diagnosis

Need for biopsy controversial

Recommended for pineal tumors

Suprasellar – biopsy considered essential

If elevated tumor marke-any AFP orβ-HCG more then 100 some consider adequate to diagnose “malignant” GCT

Slide 7

Case Presentation MN

CC: Headache

HPI: 11 year old boy who presented to OSH with a 1 month history of HA, polyuria, polydypsia and a several day history of double vision.

Imaging: MRI revealed a tumor in the pineal and pituitary region with associated hydrocephalus.