2012 EDUCATIONAL BOOK - American Society of Clinical Oncology

SAFETY OF DIPG BIOPSY IN CHILDREN
Fig. 1. Plan neuroimaging that shows the trajectory
from a trancerebellar approach. E � Entry; T � Target.
(A) Three-dimensional neuroimaging plan. (B) Axial
gadolinium-enhanced T1-weighted magnetic resonance
image. (C) Sagittal gadolinium-enhanced T1-weighted
magnetic resonance image. (D) Coronal gadoliniumenhanced
T1-weighted magnetic resonance image.
In addition, to increase direct application of chemotherapeutic
agents to the DIPG, attempts have been pursued to
circumvent the blood-brain barrier using the convectionenhanced
delivery technique. Theoretically, the safety of
this procedure is similar to that of biopsy. Preclinical models
and clinical trials have demonstrated the feasibility, efficacy,
and safety of this technique. 24 Moreover, two children
with brainstem lesions demonstrated no neurologic deficits
after infusion. 25 Therapeutic protocols are currently under
way, but the choice of the appropriate agent to deliver with
this technique remains in question.
Fig. 2. Plan neuroimaging showing the trajectory
with a transfrontal approach. E � Entry; T � Target.
(A) Three-dimensional neuroimaging plan. (B) Axial
gadolinium-enhanced T1-weighted magnetic resonance
image. (C) Sagittal gadolinium-enhanced T1-weighted
magnetic resonance image. (D) Coronal Gadoliniumenhanced
T1-weighted magnetic resonance image.
Why Perform a Biopsy for Patients with Newly
Diagnosed DIPG?
The lack of samples from patients with newly diagnosed
DIPG has limited our understanding of tumor biology, which
hinders the development of newer therapies for patients
with these devastating tumors. As targeted therapy development
undoubtedly requires tissue, it could be argued that
such advances will only be optimized with the knowledge
that biopsies provide in terms of tumor biology and the
identification of new targets. In recent papers, authors
defend the idea that a biopsy of patients with newly diag-
631