Objective:

To evaluate the clinical value of technetium-

99m

labelled small molecule against prostate specific membrane antigen (PSMA) (HYNIC-Glu-Urea-A

99m

Tc-PSMA) in the detection of primary and metastatic prostate cancers.

Methods:

A total of 69 consecutive prostate cancer patients wh

o received

99m

Tc-PSMA SPECT/CT were retrospectively analyzed. The sensitivity of

99m

Tc-PSMA for the detection of the primary and metastatic lesions was evaluated. The relationships between positive

99m

Tc-PSMA and prostate specific antigen (PSA) level and Gleason score were analyzed.

Results:

Of all patients

6 cases with PSA0.2 ng/mL after radical prostatectomy remained biochemically disease-free. Based on per patient

in 77.8% (49/63) of thepatients at least one lesion indicative of prostate cancer was detected by

99m

Tc-PSMA SPECT/CT. The level of PSA in the patients with positive

99m

Tc-PSMA imaging was significantly higher than that in the patients with negative

99m

Tc-PSMA imaging (PSA median 25.52 ng/mL

range: 0.85-3 239 ng/mL)

vs.

(PSA median 0.35 ng/mL

range: 0.003-9.28 ng/mL)(

P

0.001). Among newly diagnosed patients and recurrent patients with PSA1.0 ng/mL

99m

Tc-PSMA imaging was able to detect lesions with improved sensitivity of 97.4% (37/38); furthermore

among recurrent patients with PSA10.0 ng/mL

the number and extent of lesions detected by

99m

Tc- PSMA SPECT/CT increased significantly. Gleason score in the patients with positive

99m

Tc-PSMA imaging was significantly higher than that in the patients with negative

99m

Tc-PSMA imaging (

P

0.001).

Conclusion:

Among newly diagnosed prostate cancer patients and recurrent patients with PSA1.0 ng/mL

99m

Tc-PSMA SPECT/CT can detect prostate cancer and metastases in a high number of patients and can provide important information for clinical treatment decision.