Recurrence rate after radical prostatectomy following primary staging of high-risk prostate cancer with ⁶⁸Ga-PSMA PET/CT

Figures & data

Figure 1. Flow chart of inclusion of high-risk prostate cancer patients treated by radical prostatectomy in the study. *Refers to treatment with antiandrogens, surgical or chemical castration therapy, ²²³Radium, and early or late chemotherapy (most commonly Docetaxel or Cabazitaxel).

Table 1. Characteristics of radical prostatectomy (RP) specimens in the ⁶⁸Ga-PSMA PET/CT cohort and in the ^99mTc bone scintigraphy and CT-TAP cohort.

Characteristics of radical prostatectomy (RP) specimens
	All ^68Ga-PSMA PET/ CT patients	^68Ga-PSMA PET/ CT BCR patients	All ^99mTc bone scintigraphy and CT-TAP patients	^99mTc bone scintigraphy and CT-TAP BCR patients
Patients, n (%)	247 (100.0%)	63 (25.5%)	137 (100.0%)	68 (49.6%)
Patients with PLND*
Yes, n (%)	177 (71.7%)	55 (31.1%)	69 (50.4%)	45 (66.2%)
No, n (%)	70 (28.3%)	8 (11.4%)	68 (49.6%)	23 (33.8%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	8 (5.8%)	5 (7.4%)
Any positive lymph nodes from PLND**
Yes, n (%)	36 (20.3%)	25 (45.5%)	10 (14.5%)	9 (20.0%)
No, n (%)	141 (79.7%)	30 (54.5%)	59 (85.5%)	36 (80.0%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)
Positive resection margin
Yes, n (%)	67 (27.1%)	30 (47.6%)	50 (36.5%)	34 (50.0%)
No, n (%)	180 (72.9%)	33 (52.4%)	80 (58.4%)	28 (41.2%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	7 (5.1%)	6 (8.8%)
ISUP grade in RP specimens
1, n (%)	10 (4.0%)	1 (1.6%)	16 (11.7%)	2 (2.9%)
2, n (%)	96 (38.9%)	13 (20.6%)	76 (55.5%)	33 (48.5%)
3, n (%)	60 (24.3%)	18 (28.6%)	17 (12.4%)	8 (11.8%)
4, n (%)	47 (19.0%)	13 (20.6%)	17 (12.4%)	15 (22.1%)
5, n (%)	34 (13.8%)	18 (28.6%)	3 (2.2%)	2 (2.9%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	8 (5.8%)	8 (11.8%)
Pathological stage
pT1, n (%)	0 (0.0%)	0 (0.0%)	8 (5.8%)	2 (2.9%)
pT2, n (%)	139 (56.3%)	13 (20.6%)	81 (59.1%)	27 (39.7%)
pT3, n (%)	108 (43.7%)	50 (79.4%)	41 (29.9%)	32 (47.1%)
pT4, n (%)	0 (0.0%)	0 (0.0%)	1 (0.7%)	1 (1.5%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	6 (4.4%)	6 (8.8%)
Prostate weight (g), formalin-fixed
Median (range)	61.0 (30.0–175.0)	59.0 (33.0–175.0)	–	–
<50, n (%)	57 (23.1%)	15 (23.8%)	–	–
50–100, n (%)	162 (65.6%)	43 (68.3%)	–	–
>100, n (%)	28 (11.3%)	5 (7.9%)	–	–
Unknown, n (%)	0 (0.0%)	0 (0.0%)	–	–
Prostate volume (cm^3)
Median (range)	44.8 (13.4–185.1)	41.9 (15.3–121.0)	–	–
<50, n (%)	149 (60.3%)	43 (68.3%)	–	–
50–100, n (%)	85 (34.4%)	19 (30.2%)	–	–
>100, n (%)	13 (5.3%)	1 (1.6%)	–	–
Unknown, n (%)	0 (0.0%)	0 (0.0%)	–	–
Primary tumor volume (cm^3)
Median (range)	5.9 (0.2–49.2)	9.0 (1.7–48.4)	–	–
<5, n (%)	104 (42.1%)	15 (23.8%)	–	–
5–10, n (%)	72 (29.1%)	19 (30.2%)	–	–
>10, n (%)	71 (28.7%)	29 (46.0%)	–	–
Unknown, n (%)	0 (0.0%)	0 (0.0%)	–	–

*Pelvic lymph node dissection. **If pathological examination of resected lymph nodes revealed any metastases.

Table 2. Baseline and clinicopathological characteristics of the ⁶⁸Ga-PSMA PET/CT cohort and the ^99mTc bone scintigraphy and CT-TAP cohort.

Baseline and clinicopathological characteristics
	All ^68Ga-PSMA PET/ CT patients	^68Ga-PSMA PET/ CT BCR patients	All ^99mTc bone scintigraphy and CT-TAP patients	^99mTc bone scintigraphy and CT-TAP BCR patients
Patients, n (%)	247 (100.0%)	63 (25.5%)	137 (100.0%)	68 (49.6%)
Age, years
Median (range)	68.2 (46.9–78.9)	69.2 (51.0–78.9)	63.9 (48.5–84.8)	64.9 (48.9–84.8)
Follow-up time (months)
Median (range)	45.5 (27.6–62.7)	46.4 (27.8–62.6)	100.3 (6.0–231.5)	102.6 (6.0–231.5)
SUVmax*
Median (range)	14.29 (3.15–85.99)	15.60 (4.75–66.58)	–	–
Pre-operative PSA (ng/mL)
<10, n (%)	113 (45.7%)	25 (22.1%)	57 (41.6%)	23 (33.8%)
10–20, n (%)	79 (32.0%)	23 (29.1%)	33 (24.1%)	17 (25.0%)
>20, n (%)	55 (22.3%)	15 (27.3%)	46 (33.6%)	27 (39.7%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	1 (0.7%)	1 (1.5%)
ISUP grade in biopsies
1, n (%)	26 (10.5%)	3 (11.5%)	25 (18.2%)	7 (10.3%)
2, n (%)	38 (15.4%)	6 (15.8%)	29 (21.2%)	16 (23.5%)
3, n (%)	27 (10.9%)	8 (29.6%)	6 (4.4%)	6 (8.8%)
4, n (%)	116 (47.0%)	32 (27.6%)	21 (15.3%)	13 (19.1%)
5, n (%)	40 (16.2%)	14 (35.0%)	2 (1.5%)	2 (2.9%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	54 (39.4%)	24 (35.3%)
Clinical stage
cT1, n (%)	73 (29.6%)	9 (12.3%)	3 (2.2%)	0 (0.0%)
cT2, n (%)	121 (49.0%)	32 (26.5%)	128 (93.4%)	64 (94.1%)
cT3, n (%)	53 (21.4%)	22 (41.5%)	5 (3.6%)	3 (4.4%)
cT4, n (%)	0 (0.0%)	0 (0.0%)	0 (0.0%)	0 (0.0%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	1 (0.7%)	1 (1.5%)
Regional lymph node metastases
cN0, n (%)	231 (93.5%)	50 (21.6%)	0 (0.0%)	0 (0.0%)
cN1, n (%)	16 (6.5%)	13 (81.3%)	0 (0.0%)	0 (0.0%)
Unknown, n (%)	0 (0.0%)	0 (0.0%)	137 (100.0%)	68 (100.0%)

*Maximum standardized uptake value (SUV_max) is defined as the hottest voxel within the primary tumor (volume of interest, VOI) on the ⁶⁸Ga-PSMA PET/CT scan.

Figure 2. ⁶⁸Ga-PSMA PET/CT compared with conventional imaging in relation to recurrence-free survival (RFS) in Kaplan-Meier curve analysis with 0.95 CI. Primary staging with ⁶⁸Ga-PSMA PET/CT was significantly associated with a longer 5-year RFS rate compared with conventional imaging. The median duration of follow-up was 45.5 months in the ⁶⁸Ga-PSMA PET/CT cohort and 100.3 months in the ^99mTc bone scintigraphy and CT-TAP (thorax, abdomen, pelvis) group. The follow-up data of the conventional imaging cohort is censored at 60 months due to much longer follow-up time compared with the ⁶⁸Ga-PSMA PET/CT cohort to improve visualization.

Data availability statement

Most data supporting the reported results are provided in the paper and further data are stored by the authors.