Follow-up/Surveillance

Question 1

What is the radiographic appearance of radionecrosis?

Answer 1

Central hypodensity, ring enhancement, edema, and low PET avidity (occurs >6 mos post-RT)

Question 2

What was the grade 3–4 toxicity rate from the Stupp R et al. trial (NEJM 2005) for the RT + TMZ arm? What main toxicity was noted?

Answer 2

7%; mostly hematologic from TMZ (thrombocytopenia and lymphocytopenia)

Question 3

What does the f/u entail after RT for HGGs?

Answer 3

MRI 2–6-wks post-RT, then q2–4mos for yrs, then q6mos; weekly labs (blood counts) while on TMZ (NCCN 2018)

Question 4

What % of HGG recurrences are local?

Answer 4

80%–90% of HGG recurrences are local.

Question 5

What % of pts may show pseudoprogression after RT + TMZ?

Answer 5

Up to 50% (Taal W et al., Cancer 2008). Associated w improved survival

Question 6

Does MGMT promoter methylation status influence the incidence of pseudoprogression in HGGs?

Answer 6

Yes. MGMT methylation status increases the incidence of pseudoprogression after TMZ + RT. (Brandes AA et al., JCO 2008). If pseudoprogression 2/3 have methylated MGMT (Brandes, JCO 2008)