CNS Prognosis & RT Side Effects

Question 1

What is the prognosis for younger patients?

Answer 1

Prognosis tends to be better in younger patients with one exception; children younger than 4 present a particular problem due to radiosensitivity of developing brain tissue.

Question 2

What is the most important prognostic factor?

Answer 2

Tumor grade is the most important prognostic factor. The higher the grade, the shorter the survival time.

Question 3

What is the prognosis for benign lesions?

Answer 3

Benign lesions are indicative of a better prognosis and the potential for a cure with the use of surgery or radiation therapy.

Question 4

What are acute side effects of radiation therapy?

Answer 4

Acute side effects can occur up to 3 months after treatment, are usually temporary, and disappear without therapy.

Examples include edema, erythema, and alopecia.

Question 5

What are the doses associated with alopecia from radiation therapy?

Answer 5

Alopecia can occur at 20Gy (temporary) and 40Gy (permanent).

Question 6

What are chronic side effects of radiation therapy?

Answer 6

Chronic side effects occur 6 months to many years after irradiation, are usually irreversible and progressive.

Examples include alopecia, decreased mental function, cataract formation/blindness, and necrosis.

Question 7

How can chronic side effects be avoided?

Answer 7

Chronic side effects can be avoided by shielding or keeping eyes out of the field.