Ramathibodi Ga-68 PSMA cases

ผศ. พญ. วชิชนา จํารูญรัตน์

Wichana Chamroonrat, MD9 Nov 2018

Adapted from “Prostate cancer update” on 14 Jun 2017

“Thai SNM meeting” on 15 Dec 2017

“RT topic” dated 16 May 2018

PSMA

• Prostate Specific Membrane Antigen

• Overexpressed 100-1000times in PC compared to normal prostate tissues

• Expressed in normal tissues as salivary glands, duodenal mucosa, proximal renal tubular cells, colonic crypt

• Overexpressed in TCC, RCC, colon CA, (thyroid) endothelial cell of neovasculature

Increased PSMA expression: Prostate CA

• Increased tumor grade

• Pathologic stage

• Aneuploidy

• Biochemical recurrence

• Up-regulated when androgen independent

– Early indicator for tumor progression after ADT

– Prognostic factor for disease recurrence

– CRPC and metastatic PC

PET tracers for Prostate cancer

F-18 NaF F-18 FDG F-18 FCH Ga-68 PSMA

Tc-99m MDP

*References: PET clinics, Calabria F et.al NMB 2017

* *

F-18 FDG Ga-68 PSMA

Commercially available for prostate cancerDx F-18 PSMARx Lu-177 PSMA

2018 Urology Clinic of North America

Ga-68 PSMA

• Dose 0.05-0.06mCi/kg

• Furosemide 20mg IV immediate after Ga-68 PSMA

• Uptake time 1hour

• Philips Gemini TF CT 64slides

• 2min/bed position

• 500cc plain water within 2hours prior scanning

• Urinate prior scanning

27scans(24patients)

23pt Prostate CA

6staging 17restaging

1pt

Pancreatic CA

14 Sep 2017 – 4 Oct 2018

Display favor FDG reading

FDG PSMA

More suitable for PSMA

FDG PSMA

Staging of locally advanced case with diuretic

but different display setting

Two negative PSMA casesboth: NO underling of renal impairment

NO diuretic WITH diuretic

• Primary staging in high risk disease before Sxor RT

– GS >7, PSA >20, clinical stage T2-3a

– Increase likelihood of LN and bone metastases.

– Can replace abdomen CT for nodal metastasis.

– Can’t replace pelvic MRI for local tumor delineation.

– Bone scan may add value in PSMA negative tumor or densely sclerotic bone lesion.

Ga-68 PSMA AUC by SNMMI EANM

AUC: Appropriate Use CriteriaReferences: Fendler WP EJNM 2017

27scans(24patients)

23pt Prostate CA

6staging 17restaging

1pt

Pancreatic CA

14 Sep 2017 – 4 Oct 2018

6staging

4single scan

31incidental thyroid CA

2FU

Rx response

14 Sep 2017 – 4 Oct 2018

65M PSMA PSA 13.16ng/ml, Cr 0.99mg/dlBx GS10

ST

ST

75M PSMA PSA 67ng/ml, Cr 1.07mg/dlBx GS 8

61M PSMA PSA 4.34ng/ml, Cr 0.9mg/dlBx GS3+4, plan surgery

GS 7

ST

ST

59M PSMA PSA 0.013ng/ml, Cr 0.98mg/dlPost radical prostatectomy, GS4+5

R L

63M PSMA PSA 0.108-21.25ng/ml, Cr 0.9-1.1 mg/dlPost radical prostatectomy, GS9, on ADT (PSA 189 pre ADT)

Initial PSA 21.25

Follow upPSA 0.108

ST+Res

77M PSMA PSA 4.24-7.28 ng/ml, Cr 0.68-0.76mg/dlPost TURP, GS10

Initial PSA 7.28

Follow upPSA 4.24

ST+Res

6staging (PSA)

4+ scan

1 Primary only:

67

3 primary+other

Avg 69.81

(7.28-189)

2-

-Post RP: 0.013 (+PTC)

-GS7, subcm: 4.34

14 Sep 2017 – 4 Oct 2018

• Localization of tumor tissue in recurrence prostate cancer

– PSA0.2-10ng/ml

– Higher sensitivity with shorter doubling time

– Higher initial Gleason score

Ga-68 PSMA AUC by SNMMI EANM

AUC: Appropriate Use CriteriaReferences: Fendler WP EJNM 2017

Ga-68 PSMA PET

• Meta-analysis 16articles and 1309patients

• Positive Ga-68 PSMA PET 76% with biochemical recurrence

Detection rate

• PSA 0-0.2 = 42%

• PSA 0.2-1 = 58%

• PSA 1-2 = 76%

• PSA >2 = 95%

References: Perera M EU 2016

27scans(24patients)

23pt Prostate CA

6staging 17restaging

1pt

Pancreatic CA

14 Sep 2017 – 4 Oct 2018

17restaging

biochemical recurrence

10positive

2known8

(1with FU)

7negative

14 Sep 2017 – 4 Oct 2018

FDG PET 6 mo prior

Bone scan 10mo prior

80M PSMA rising PSA 100+ ng/ml, Cr ? mg/dlProstate cancer with known bone met post bilateral orchidectomy

BR

75M PSMA PSA 0.582ng/ml, Cr 0.9mg/dlCRPC post Abiraterone (pre PSA 25.17)

Bone scan 1.5 years ago

BR+Res

77M PSMA PSA 2.22-2.71ng/ml, Cr 0.98-1.11mg/dlPost radical prostatectomy, and RT, on ADT, GS8

Before PSA 2.22

Follow upPSA 2.71

BR+Res

80M PSMA PSA 30.67ng/ml, Cr 0.73mg/dlPost radical prostatectomy

BR

Bone scan 4mo prior

68M PSMA rising PSA 32.38 ng/ml, Cr 0.98 mg/dlProstate CA post RP >10yr with local recurrence

BR

WITH diuretic

60M PSMA rising PSA 1.54 ng/ml, Cr 1 mg/dlProstate CA post brachytherapy and external RT 5 years on ADT

BR

+node FNA SBRT, later PSA 0.3

78M PSMA PSA 5.36ng/ml, Cr 1.18mg/dlBx GS3+3 with rectal cancer post CCRT and APR

?insuff Fx?

BR

Eq

85M PSMA PSA 14.1ng/ml, Cr 1.09mg/dlBx 2012 on ADT, PSA rising

BR

Pri

82M PSMA PSA 5.63ng/ml, Cr 0.92mg/dlProstate and urinary bladder cancer

BR

Pri

66M PSMA PSA 9.66ng/ml, Cr 0.77mg/dlDx 2008 post RT and ADT

BR

Pri

17restaging (PSA)

biochemical recurrence

10positive

Primary(3) No&Dis(7)

Avg 9.79

Min 5.63

Max 14.1

Avg 24.68

Min 0.582

Max >100

7negative

Avg 0.34

Min 0.003

Max 0.83

14 Sep 2017 – 4 Oct 2018

Equivocal insuff FxPSA 5.36, GS6

Emerging clinical applications

• Staging before or during PSMA directed radiotherapy (e.g. Lu-177 PSMA)

• Targeted biopsy after previous negative biopsy in patients with high suspicion of prostate cancer

• Monitoring of systemic treatment in metastatic prostate cancer

Ga-68 PSMA AUC by SNMMI EANM

AUC: Appropriate Use CriteriaReferences: Fendler WP EJNM 2017

ขอบคุณค่ะ

เวชศาสตร์นิวเคลียร์ รามาธิบดี