Intermediate Risk Prostate Ca.: CAB or just LHRH agonist?

[Scatter]

In select intermediate risk prostate ca, do you recommend short-term complete androgen blockade (i.e., LHRH agonist + antiandrogen) vs LHRH agonist alone? Thanks.

---

Members don't see this ad.

 

[Gfunk6]

LHRH agonist + 1-2 weeks of antiandrogen to blunt testosterone 'flare.'

 

[medgator]

LHRH agonist + 1-2 weeks of antiandrogen to blunt testosterone 'flare.'

Another option is a monthly LHRH "antagonist" like firmagon and switch to Lupron after three months. I do that. No casodex/testosterone flare to worry about.

 

[Neuronix]

LHRH agonist + 1-2 weeks of antiandrogen to blunt testosterone 'flare.'

Have you ever seen symptoms related to flare? We don't use the oral antiandrogens and we've never seen it. Once and awhile we'll get nervous and add bicalutamide with bulky high or very high risk disease, but that's pretty uncommon.

Though I think in the main trials they did complete androgen blockade including four months of oral antiandrogens, so that's probably the best to say for exam purposes.

 

[Gfunk6]

Have you ever seen symptoms related to flare? We don't use the oral antiandrogens and we've never seen it. Once and awhile we'll get nervous and add bicalutamide with bulky high or very high risk disease, but that's pretty uncommon.

Though I think in the main trials they did complete androgen blockade including four months of oral antiandrogens, so that's probably the best to say for exam purposes.

I've never see symptoms of flare. The rationale for short-term biclutamide is probably the fear that a short spike in testosterone will adversely impact prostate cancer prognosis.

 

[Palex80]

The only data showing you "should" give bicalutamide come from patients who were treated initially for metastatic PC with LHRH.
Some of these very advanced disease patients had then paralysis due to growing spinal mets.

There is no evidence whatsoever that if you withhold bicalutamide when giving an LHRH before definitive RT for cT2a cN0 cM0 GS 4+3=7 PSA 13 ng/ml tumor you are actually worsening local / distant control or overall survival.

 

[Cancerdancer]

There is some retrospective data
PMID: 19540066
PURPOSE:
To assess whether short-course total androgen blockade vs. a luteinizing hormone-releasing hormone (LHRH) agonist alone affects the risk of prostate cancer-specific mortality (PCSM) in men with localized but high-risk disease treated with radiotherapy.

METHODS AND MATERIALS:
The study cohort comprised 628 men with T1-T4, N0, M0 prostate cancer with high-risk disease (prostate-specific antigen level >20 ng/mL, Gleason score >or=8, or clinical category >or=T3) treated with 45 Gy of external beam radiotherapy followed by a brachytherapy boost in addition to receiving a median of 4.3 (interquartile range [IQR], 3.6-6.4) months of hormonal blockade with an LHRH agonist plus an antiandrogen or monotherapy with an LHRH agonist. Fine and Gray's multivariable regression analysis was used to determine whether combination androgen suppression therapy (AST) vs. monotherapy affected the risk of PCSM, adjusting for treatment year, duration of AST, age, and known prognostic factors.

RESULTS:
After a median follow-up of 4.9 (IQR, 3.5-6.5) years, men receiving combination AST had a lower risk of PCSM than those treated with monotherapy (adjusted hazard ratio [AHR], 0.18; 95% confidence interval [CI], 0.04-0.90; p = 0.04). An increasing prostate-specific antigen level (AHR, 2.70; 95% CI, 1.64-4.45; p < 0.001) and clinical category T3/4 disease (AHR, 29.6; 95% CI, 2.88-303.5; p = 0.004) were also associated with an increased risk of PCSM.

CONCLUSIONS:
In men with localized but high-risk prostate cancer treated with external beam radiotherapy and brachytherapy, short-course AST with an LHRH agonist plus an antiandrogen is associated with a decreased risk of PCSM when compared with monotherapy with an LHRH agonist.

 

[Palex80]

That is not the same thing.

You are quoting a paper comparing LHRH vs. LHRH+Bicalutamide. Median duration of antihormonal treatment was 4+ months either as sole LHRH or combination treatment.

We were discussing whether or not giving 1 month of Bicalutamid when starting LHRH-therapy in combination with RT may change prognosis. That's a totally different situation, since you are merely giving the bicalutamide to prevent a PSA flare, not as more powerful (total) androgen blockade.

 

[medgator]

That is not the same thing.

You are quoting a paper comparing LHRH vs. LHRH+Bicalutamide. Median duration of antihormonal treatment was 4+ months either as sole LHRH or combination treatment.

We were discussing whether or not giving 1 month of Bicalutamid when starting LHRH-therapy in combination with RT may change prognosis. That's a totally different situation, since you are merely giving the bicalutamide to prevent a PSA flare, not as more powerful (total) androgen blockade.

It's confusing because of the OP. The op asked about CAB in his title but then asked about short term antiandrogen therapy in his actual post.

 

[Cancerdancer]

Yeah, I presumed when he asked short-term CAB vs LHRH alone he was asking "4-6 mo CAB vs 4-6 mo lupron alone" using the short-term to indicate that this is the intermediate risk protocol of ADT as opposed to 28 mo or whatever. There is no reason to block the flare in intermediate risk disease as someone above pointed out, only if concerned for cord compression or worsened obstructive problems in bulky/metastatic disease. The data I quoted gets to the pertinent question (albeit not in int-risk pts specifically), which is do we need to use CAB (as used by all trials establishing ADT+RT as superior to RT alone) or just LHRH agonist as often done currently.

 

[Scatter]

Thanks everyone, esp. Cancer Dancer -- I was looking for this.