682 692
2.3.
Plasma collection and RNA extraction from exosomes
Overall, 3 ml of blood were collected before the start of
abiraterone or enzalutamide; in seven participants, a
sample was also available at disease progression. Blood
was transferred in ethylenediaminetetraacetic acid tubes
and centrifuged at 1900
g
for 10 min at 4
8
C within 2 h after
drawing. Plasma was stored at 80
8
C until analysis. Plasma
Table 1 – Characteristics of patients and androgen receptor splice variant 7 status
Baseline characteristic
All patients
AR-V7
S
AR-V7
+
n
= 36
n
= 22
n
= 14
Age, median (range), y
66 (51–81)
67 (51–81)
66 (57–73)
Race,
n
(%)
White
36 (100)
22 (100)
14 (100)
Nonwhite
0 (0)
0 (0)
0 (0)
ECOG performance status,
n
(%)
0
26 (72)
17 (77)
9 (64)
1 or 2
10 (28)
5 (23)
5 (36)
Time since diagnosis, median (range), yr
4.86
(0.32–17.03)
5.64
(0.91–17.03)
3.60
(0.32–12.80)
Tumor stage at diagnosis,
n
(%)
T1/2
3 (8)
2 (9)
1(7)
T3/4
13 (36)
9 (41)
4 (29)
Unknown
20 (56)
11 (50)
9 (64)
Gleason sum at diagnosis,
n
(%)
7
16 (44)
12 (55)
4 (29)
8
19 (53)
9 (41)
10 (71)
Unknown
1 (3)
1 (4)
0 (0)
Type of local treatment,
n
(%)
Surgery
17 (47)
11 (50)
6 (43)
Radiation therapy
10 (28)
8 (36)
2 (14)
None
9 (25)
3 (14)
6 (43)
No. of prior hormonal therapies, median
2
2
2
Current treatment,
n
(%)
Abiraterone
26 (72)
18 (82)
8 (57)
Enzalutamide
10 (28)
4 (18)
6 (43)
Docetaxel
0 (0)
0 (0)
0 (0)
Cabazitaxel
0 (0)
0 (0)
0 (0)
Prior use of abiraterone,
n
(%)
Yes
4 (11)
0 (0)
4 (28)
No
32 (89)
22 (100)
10 (72)
Prior use of enzalutamide,
n
(%)
Yes
0 (0)
0 (0)
0 (0)
No
36 (100)
22 (100)
14 (100)
Prior use of docetaxel,
n
(%)
Yes
24 (67)
11 (50)
13 (93)
No
12 (33)
11 (50)
1 (7)
Prior use of cabazitaxel,
n
(%)
Yes
5 (14)
1 (5)
4 (29)
No
31(86)
21(95)
10 (71%)
Presence of bone metastases,
n
(%)
Yes
30 (83)
16 (73)
14 (100)
No
6 (17)
6 (27)
0 (0)
Presence of lymph node metastases,
n
(%)
Yes
23 (64)
13 (59)
10 (71)
No
13 (36)
9 (41)
4 (29)
Presence of visceral metastases,
n
(%)
Yes
7 (19)
1 (5)
6 (43)
No
29 (81)
21 (95)
8 (57)
Baseline PSA level, ng/ml, median (range)
26.3
(0.63–4581)
22.3
(0.78–4581)
99.6
(0.63–521)
Baseline alkaline phosphatase level, U/l, median (range)
180
(49–917)
152
(49–917)
258
(53–575)
Baseline lactase dehydrogenase level, U/l, median (range)
220
(110–1723)
220
(110–1723)
266
(150–1720)
Baseline Hb level, g/dl, median (range)
12.3
(7.9–14.9)
13.25
(9.9–14.9)
10
(7.9–12)
Use of opioid,
n
(%)
Yes
14 (39)
5 (23)
9 (75)
No
22 (61)
17 (77)
5 (25)
AR-V7 = androgen receptor splice variant 7; ECOG = Eastern Cooperative Oncology Group; Hb = hemoglobin; PSA = prostate-specific antigen.
E U R O P E A N U R O L O G Y 7 1 ( 2 0 1 7 ) 6 8 0 – 6 8 7
682