Dose Constraints

Question 1

What is the dose constraint for the kidney?

Answer 1

One-third of contralat kidney <14.4 Gy

Question 2

What is the dose constraint for the liver?

Answer 2

One-half of uninvolved liver <19.8 Gy; with liver mets, 75% of liver ≤30.6 Gy

Question 3

Pts are at risk for what late effects with flank RT? WLI?

Answer 3

Scoliosis of the spine, muscular hypoplasia, kyphosis, iliac wing hypoplasia, SBO, veno-occlusive Dz of the liver.

Breast hypoplasia (four-fifths of females who get WLI will have underdeveloped breasts), pneumonitis, CHF, 2nd malignancy, and renal failure

Question 4

What is the risk of SBO at 15 yrs after flank/abdominal RT?

Answer 4

15%.

Question 5

What is the risk of a 2nd malignancy at 15 yrs?

Answer 5

1.6%–2%.

Question 6

The reirradiation tolerance of which organ decreases with time after initial RT?

Answer 6

Reirradiation tolerance of the kidney decreases with time.

Question 7

What is the TD 5/5 for an entire kidney?

Answer 7

The TD 5/5 is 23 Gy.

Question 8

What is the cumulative max total dose (including prior RT) for WT pts?

Answer 8

30.6 Gy (if <3 yrs) or 39.5 Gy (if >3 yrs)