Campbell Prostate Cancer + NCCN 2.2021 Flashcards
(88 cards)
The American Brachytherapy Society guidelines suggest that prostate glands that are greater than ___ are technically more difficult to implant because of: ___ and ___;
___ can reduce prostate volumes by ___ % to optimize gland before brachytherapy
60cm
- increased frequency of pubic arch interference - large number of seeds required
Cytoreductive ADT
25% to 40%
Prostate volumes in excess of ___ may require ___ before RT to reduce volume of rectum or bladder exposed to radiation.
Neoadjuvant ADT for cytoreduction
Transurethral resection of the prostate (TURP) ____ (before or after?) external radiation, rather than after, may be advisable for men in, or at risk of, retention.
BEFORE radiation!
** post-treatment transurethral resection is performed, there may be a higher associated risk of incontinence (Polland et al., 2017), particularly after brachytherapy with up to 18% of men incontinent after TURP
Contraindications to RT for prostate cancer
Previous radical pelvic irradition
Previous pelvic surgery: potentially trap bowel within pelvic field
PResence of substantial or susceptible bowel (hernia ex.)
Poor tissue healing (chronic steroid therapy)
Risk strat:
Very low
• T1c AND
• Gleason score ≤6/grade group 1 AND
• PSA <10 ng/mL AND
• Fewer than 3 prostate biopsy fragments/cores
positive, ≤50% cancer in each fragment/core AND
• PSA density <0.15 ng/mL/g
Imaging: NOT indicated
Risk strat:
Low
- T1–T2a AND
- Gleason score ≤6/grade group 1 AND
- PSA <10 ng/mL
Imaging: NOT indicated
Risk strat:
Favorable intermediate
- T2b–T2c OR
- Gleason score 3+4=7/grade group 2 OR
- PSA 10–20 ng/mL AND
- Percentage of positive biopsy cores <50%
Imaging:
• Bone imaging: not recommended for staging
• Pelvic ± abdominal imaging: recommended if
nomogram predicts >10% probability of pelvic lymph node involvement
Risk Strat:
Unfavorable intermediate
• T2b–T2c OR
• Gleason score 3+4=7/grade group 2 or Gleason
score 4+3=7/grade group 3 OR
• PSA 10–20 ng/mL
Imaging:
- Bone imaging: recommended if T2 and PSA >10 ng/mL
- Pelvic ± abdominal imaging: recommended if nomogram predicts >10% probability of pelvic lymph
Risk strat:
High
• T3aOR
• Gleason score 8/grade group 4 or Gleason score
4 +5=9/grade group 5 OR
• PSA >20 ng/mL
Imaging:
• Bone imaging: recommended
• Pelvic ± abdominal imaging: recommended if
nomogram predicts >10% probability of pelvic lymph
Risk strat:
Very high
• T3b–T4 OR
• Primary Gleason pattern 5 OR
• >4 cores with Gleason score 8–10/grade group 4
or 5
Imaging:
• Bone imaging: recommended
• Pelvic ± abdominal imaging: recommended if
nomogram predicts >10% probability of pelvic lymph
Observation is most frequently employed in ___ .
General ffu consists of:
Men at low risk of prostate cancer death
Periodic PSA testing, clinical exam, use of imaging to monitor progression
SURVEILLANCE should be recommended as the best care option for ___ and preferable care option for ___ localized prostate cancer.
best for VERY LOW RISK
preferable for LOW RISK
Death in men on active surveillance, most commonly from ___
Cardiovascular disease
** Rarely from prostate cancer
Risk factors:
____ race found be associated withdverse pathologic outcomes such as positive surgical margins, upgrading, or upstaging.
African-American race
A history of ___ is significant and may reflect a germline disposition to prostate cancer.
A history of metastatic disease at a young age (<60) in a first-degree relative
Advising men to ____ is the single most cost-effective health intervention in the entire edifice of medical practice.
QUIT SMOKING!
Patients taking ___ in the SELECT trial had an increased risk of prostate cancer.
Patient consuming >=140 micrograms/day of supplemental ___ had 2.6 times greater disease-specific mortality.
Vitamin E
Selenium
Lifestyle recommendations for active surveillance: ___
- Exercise regularly, and include vigorous activity if possible.
- Maintain a healthy weight.
- Stop smoking.
- Eat a vegetable- and grain-based diet; moderate red meat consump-
tion, especially processed meats; if eating meat, rely on fish and
skinless poultry. - Limit saturated fat intake.
- Take vitamin D, 1000 to 2000 IU/day, especially during periods
of reduced sunlight. - Consider a low-dose statin.
IMRT
Intensity-modulated radiation therapy
IMRT employs more complex, dynamic beam shapes wherein the intensity of radiation is varied across the beam (as opposed to uniform intensity across the beam in 3DCRT)
Low-dose-rate Brachytherapy
Permanent seed implantation: Delivers a dose over a number of weeks to months depending on the isotope chosen, hence the term low- dose-rate
125Iodine emits low-energy x-rays at 27 keV, with a half-life of 59.6 days.
103Palladium was introduced in 1986 because it has an energy spectrum similar to that of 125I, with 21-keV x-rays, but with a significantly shorter half-life of 17 days.
131Cesium, which emits x-rays at 30 keV (thereby offering dose characteristics similar to 125I)
High-dose-rate Brachytherapy
Delivers short but high doses of radiation using temporary catheters
Hollow catheters are placed through the perineum into the prostate using the same procedure as for LDR brachytherapy
iridium-192 (192Ir)
Advantages of HDR vs. LDR Brachytherapy:
The use of catheters allows for more ready inclusion of extracapsular
disease and seminal vesicles, if desired.
• There is greater opportunity for dose optimization by modifying
dwell times and positions of the source within the catheters.
• The use of high doses per fraction has a potential biologic dose advantage for prostate cancer if a low alpha/beta ratio exists.
• No need for personnel to handle the radioactive source during
treatment.
• The use of a single source for all patients using a multipurpose
facility makes HDR brachytherapy potentially more cost-effective.
Potential disadvantages for HDR versus LDR brachytherapy include: • There are potential treatment inaccuracies caused by catheter and organ/patient movement between imaging and time of source insertion (during treatment planning) or between fractions, interobserver contouring variabilities, and effects of edemaThe relatively high activity and energy of the 192Ir source requires
availability of a shielded room for treatment delivery.
• There are less favorable pathologic response results from avail- able post-treatment biopsy studies
Major acute toxicity of brachytherapy is ___
Obstructive and irritative uropathy
Low but non-negligible risk of need for temporary catheterization.
Relative contraindications to brachytherapy:
Large TURP defects, TURP within prior 3-6months
Factors assoc. with poor urinary outcomes or obstruction: Qmax < 10, IPSS >20, large median lobe
Prior pelvic RT
Connective tissue disease or IBD
Pubic arch interference
Lithotomy position
Rectal fistula or lack of TRUS access
