Stereotactic radiotherapy for prostate cancer: A review and future directions

Table 1 Summary of stereotactic body radiotherapy prostate trials and retrospective analyses

Study	No. of patients	Dose	Median follow-up	Biochemical RFS	Overall survival	PSA response	BF1	PSA bounce
Madsen (IJROBP, 2007)	40	6.7 Gy × 5 Fx	41 mo	90% at 48 mo		18 mo time to nadir	3	“Few"
Pham (IJROBP, 2010)	40	6.7 Gy × 5 Fx	60 mo	93% at 60 mo	75% at 60 mo	Median nadir of 0.65 ng/mL at median time of 24 mo		22.50%
Boike (JCO, 2011)	15/15/15 (45 tot)	9/9.5/10 Gy × 5 Fx	30/18/12 mo	100% at median follow-up	100% at median follow-up	Mean < 0.4 ng/mL at 12 mo for all cohorts	0	"Multiple"
Katz (BMC Urol, 2010)	50/254 (304 tot)	7/7.25 Gy × 5 Fx	30/17 mo	35 Gy: 88% < 1 ng/mL PSA at 30 mo 36.25 Gy: 81% < 1 ng/mL PSA at 24 mo2	94%/99% at median follow-up. No deaths due to prostate cancer	28.1% < 0.5 ng/mL at 12 mo	4	37
Jabarri (IJROBP, 2012)	20/18 (38 tot)	9.5 Gy × 4/2 Fx	18.1/23.5 mo	100% at median follow-up		Median of 0.35 ng/mL at 18.3 mo	0
King (IJROBP, 2012)	67	7.25 Gy × 5 Fx	2.7 yr	94% at 4 yr		Median of 0.50 ng/mL at follow-up	2
McBride (Cancer, 2012)	34/10/1 (45 tot)	7.5/7.25 Gy × 5 Fx, 1 received "other regimen"	44.5 mo	95.5%/97.5% at 3 yr	97.7% at 3 yr	Median of 0.2 ng/mL at follow-up	0	9
Anwar (Rad Oncol, 2016)	24/26 (50 tot)	9.5/10.5 Gy boost in 2 Fx	42.7 mo	95%/95%/90% at 3/4/5 yr		Median nadir of 0.05 ng/mL at median time of 26.2 mo	4	2
Mantz (Fontiers Rad Oncol, 2014)	102	8 Gy × 5 Fx	Min. of 5 yr	99% at 6 yr		Mean of 0.27 ng/mL at 24 mo	1	15
Hannan (Eur J Cancer, 2016)	92	9/9.5/10 Gy × 5 Fx	54 mo (pooled phase I/II)	98.6% at 5 yr	94%/89.7% at 3/5 yr	Median of 0.125 ng/mL at 42 mo	1	19
Freeman (Rad Oncol, 2011)	41	7-7.25 Gy × 5 Fx	5 yr	93% at 5 yr		Median nadir of 0.3 ng/mL at follow-up	3
Davis (Cureus, 2015)	437	7-7.4 Gy × 5 Fx, 9.5 Gy × 4 Fx, 19.5-29 Gy boost	20 mo	96.1% combined at 2 yr 99.0%/94.5%/89.8% for low/intermediate/high-risk at 2 yr		Median of 0.4 ng/mL at 24 mo	15	35

¹Biochemical failure;

²Values reflect only patients who did not receive hormone therapy.

Table 2 Summary of genitourinary toxicities for included stereotactic body radiotherapy trials

Study	Acute			Late			Clinical notes
	Gr. 1	Gr. 2	Gr. ≥ 3	Gr. 1	Gr. 2	Gr. ≥ 3
Madsen (IJROBP, 2007)	28%	21.50%	1 tot	25%	20%	0%	Gr. 3 event was urinary obstruction that resolved
Pham (IJROBP, 2010)				22.50%	12.50%	2.50%	All toxicities resolved
Boike (JCO, 2011)1	28.80%	22.20%	0%	13.30%	8.80%	2 tot	Gr. 3 events due to dysuria and cystitis
Katz (BMC Urol, 2010)1	74.60%	4.60%	0%	4.70%	5.10%	1 tot
Jabarri (IJROBP, 2012)	29%	42%	0%	1 tot	8%	2 tot	One case each of urge incontinence and irritation requiring catheterization
King (IJROBP, 2012)1	Not reported	Not reported	Not reported	22.80%	5.30%	2 tot	Gr. 3 patients both underwent repeated urologic instrumentation for post-SBRT dysuria
McBride (Cancer, 2012)	59%	19%	0%	17%	17%	1 tot	Gr. 3 event was urinary obstruction requiring TURP
Anwar (Rad Oncol, 2016)	48%	37%	0%	21%	25%	1 tot	Gr. 3 event was urinary obstruction
Mantz (Fontiers Rad Oncol, 2014)	32.3% frequency, 16.6% dysuria, 7.8% retention		2 tot	19.6% frequency, 2.9% dysuria, 4.9% retention		0%	Gr. 3 events were urinary frequency
Hannan (Eur J Cancer, 2016)1	48.40%	22.00%	0%	24.20%	20.90%	5.50%	1 late Gr. 4 event (cystitis requiring ureteroileal diversion)
Freeman (Rad Oncol, 2011)	Not reported	Not reported	Not reported	25%	7%	1 tot	Gr. 3 event after repeated urologic instrumentation
Davis (Cureus, 2015)	19%/3%/3%2	2%/1%/1%2	0%	25%/4%/5%2	8%/2%/2%2	0%

¹Aggregate values for all cohorts;

²Notation as follows: urinary frequency/urinary retention/cystitis. TURP: Transurethral resection of the prostate.

Table 3 Summary of gastrointestinal toxicities for included stereotactic body radiotherapy prostate trials

Study	Acute			Late			Clinical notes
	Gr. 1	Gr. 2	Gr. ≥ 3	Gr. 1	Gr. 2	Gr. ≥ 3
Madsen (IJROBP, 2007)	26%	13%	0%	30%	7.50%	0%	Gr. 2 events were proctitis
Pham (IJROBP, 2010)				22.50%	7.50%	0.00%	All toxicities resolved
Boike (JCO, 2011)1	33%	22.50%	0%	22.20%	2 tot	1 tot	Gr. 4 event due to rectal ulcer
Katz (BMC Urol, 2010)1	74.90%	3.60%	0%	5.10%	2.30%	0%
Jabarri (IJROBP, 2012)	21%	11%	0%	2 tot	1 tot	0%
King (IJROBP, 2012)1	Not reported	Not reported	Not reported	14.00%	1 tot	0%
McBride (Cancer, 2012)	31%	7%	0%	7%	7%	2 tot	Gr. 3 events were proctitis requiring ablation
Anwar (Rad Oncol, 2016)	42%	10%	0%	12.50%	0%	0%
Mantz (Fontiers Rad Oncol, 2014)	0%	0%	0%	3 tot	0%	0%	Toxicity was rectal bleeding
Hannan (Eur J Cancer, 2016)1	37.40%	20.90%	2 tot	25.30%	13.20%	6.60%	1 acute and 2 late Gr. 4 events (one rectal bleed)
Freeman (Rad Oncol, 2011)	Not reported	Not reported	Not reported	13%	1 tot	0%
Davis (Cureus, 2015)	4%/1%/1%2	1%/0%/0%2	0%	4%/3%/3%2	0%	0%

¹Aggregate values for all cohorts;

²Notation as follows: Diarrhea/constipation/proctitis.