Long Term
Side Effects of Prostate Radiation
| Long term side effects (or
complications) are those that show up after 6 to 9 months and may last for months, years
or be permanent. These are caused by damage to normal structures that does not heal
completely and is related to the volume (amount) or normal tissue hit by the beam (the
more tissue hit, the more likely a complication) the dose (the the higher the dose the
greater the risk) and individual sensitivity (some patients will have problems even with
relatively low or 'safe' doses.) The risk of delayed bowel problems may last
for 5 years (go
here)..
Read the more complete section on side effects of
radiation to the abdomen/pelvis (here)
and rectum (here)
and the nursing instruction sheets
here. |
Radiation Complications (from RTOG Trials)
|
Total |
12.6% |
|
Bowel or Rectal |
3.3% |
|
Bladder or Urethra |
7.7% |
|
Other |
1.6% |
The chance of such a serious
complication that surgery would be required (e.g. colostomy) is very small
Radiation Complications Requiring
Surgery
ACR Patterns of Care Studies
| 1973 |
1.8% |
| 1978 |
2.3% |
| 1983 |
1.6% |
The complications are lower if less of the normal tissue is hit, so smaller (S) fields or
3D conformal (C) therapy will have less side effects than whole pelvis (W) radiation as
noted:
|
Complications from Prostate
Radiation by Technique
(short and long term side effects, Harvard study, dose 66Gy)
|
effect |
W |
S |
C |
All |
|
diarrhea |
15% |
8% |
12% |
11% |
|
nocturia |
57% |
38% |
42% |
43% |
|
impotency |
44% |
32% |
20% |
31% |
J Clin Onc 1997:15:227
The higher the dose of radiation
the more likely the complications as noted:
Bowel Complications by Dose of
Conventional Technique Radiation
|
Dose |
Grade 2 Injury |
Grade 3 Injury |
|
6500 - 6790cGy |
6.5% |
0% |
|
6800 - 7090cGy |
9.4% |
1.4% |
|
7100 - 7400cGy |
27% |
1.8% |
IJROBP 1997;37:3
| Compared to surgery (radical
prostatectomy) radiation is more likely to cause bowel problems but less likely to cause
bladder control problems or impotence as noted: |
Side Effects at 12 Months (Harvard Study)
|
symptom |
Radical Prostatectomy |
Radiation |
|
diarrhea |
6% |
12% |
|
urinary frequency |
19% |
10% |
|
incontinence (using pads) |
35% |
5% |
|
impotence |
93% |
67% |
J Clin Onc 1998;16:269
| The risk of impotence after surgery
(even with 'nerve sparing' surgery) is much higher than after radiation particularly in
older men as noted: |
Potency Rate by Age comparing conformal
radiation
(XRT) with nerve sparing radical prostatectomy (S)
| Age |
< 50y |
50-59y |
60-69y |
70y+ |
| XRT |
na |
88% |
71% |
79% |
| Surg |
79% |
79% |
60% |
33% |
Mantz IJROBP 1997;37:551
| Patients who develop impotence after
radiation may respond to Viagra, though this drug does carry some risks and you should
consult a urologist about other treatments (e.g. prostatglandins like alprostadil) see
below: |
Deaths of Men Treated for Impotence (data though 7/8/99 from JAMA 2000;283:590)
|
Drug |
deaths reported |
prescriptions |
death/million prescriptions |
|
Caverject (alprostadil injection) |
5 |
~ 1.3 million |
4.5 |
|
MUSE (transurethral alprost) |
2 |
~ 1.3 million |
1.5 |
|
Yacon (yohimbine) |
1 |
~4.0 million |
0.25 |
|
Viagra (sildenafil) |
564 |
~11.0 million |
49 |
