Research ArticleTheranostics

Rapid Modulation of PSMA Expression by Androgen Deprivation: Serial 68Ga-PSMA-11 PET in Men with Hormone-Sensitive and Castrate-Resistant Prostate Cancer Commencing Androgen Blockade

Louise Emmett, Charlotte Yin, Megan Crumbaker, George Hruby, Andrew Kneebone, Richard Epstein, Quoc Nguyen, Adam Hickey, Noah Ihsheish, Gordon O’Neill, Lisa Horvath, Venu Chalasani, Phillip Stricker and Anthony M. Joshua
Journal of Nuclear Medicine July 2019, 60 (7) 950-954; DOI: https://doi.org/10.2967/jnumed.118.223099

Article Figures & Data

Figures

  • FIGURE 1.
    FIGURE 1.

    Metastatic bone disease demonstrated marked reduction in PSMA SUVmax from baseline ([A] SUVmax 8) to day 9 ([B] SUVmax 3) (red arrow), in response to LHRH + bicalutamide (patient C in Fig. 2).

  • FIGURE 2.
    FIGURE 2.

    Serial-time-point PSMA PET imaging measuring SUVmax (A) and serial serum PSA (B) in men with hormone-sensitive PCa commencing LHRH ± bicalutamide.

  • FIGURE 3.
    FIGURE 3.

    A man with newly diagnosed extensive bone metastases on PSMA PET (patient E in Fig. 2). PSMA SUVmax of 35 at baseline (A) initially showed a reduction to an SUVmax of 20 at day 9 (B). This then increased to an SUVmax of 65 at day 28 (C), although the total volume of disease was significantly reduced by day 28. There was a marked PSA response to treatment (−90%), although PSA response was short lived on follow-up.

  • FIGURE 4.
    FIGURE 4.

    All men with mCRPC experienced an increase in PSMA SUVmax and SUVmean in response to androgen-signaling inhibition. This man (patient B in Fig. 5) had an increase in SUVmax from 20 at baseline (A) to 30 at day 9 (B) and an increase in the number of metastatic lesions visible on PSMA PET (red arrows).

  • FIGURE 5.
    FIGURE 5.

    Increase in PSMA SUVmax was noted in all men with mCRPC commencing androgen-signaling inhibition. PSA response in men with mCRPC commencing androgen-signaling inhibition after LHRH was slower, with 2 of 7 demonstrating progression of PSA on treatment.

Tables

  • TABLE 1

    Patient Characteristics

    CharacteristicCohort 1Cohort 2
    Age (y)69 (59–82)72 (59–81)
    Time from diagnosis (mo)2.3 (0.7–2.7)24 (11.3–147.4)
    Gleason score
     74/82/7
     81/81/7
     9–103/84/7
    Baseline PSA80 (15–148)9.2 (4.9–490)
    Baseline testosterone (nmol/L)11.6 (6.5–27.7)0.3 (0.3–1.6)
    Prior treatment
     None8/8—
     LHRH—7/7
     Docetaxel—2/7
     Treatment on trial
     LHRH + bicalutamide7/8—
     LHRH1/87/7
     Abiraterone—1/7
     Enzalutamide—6/7

    • Data in parentheses are IQRs.

  • TABLE 2

    Comparison of Clinical and Imaging Parameters between Baseline, Day 9, and Day 28 After Commencing AB in both Hormone-Sensitive (C1) and Castrate-Resistant (C2) Disease States

    VariableBaseline (C1)Day 9 (C1)Day 28 (C1)Baseline (C2)Day 9 (C2)Day 28 (C2)
    Number of men8/87/88/87/76/77/7
    PSA (ng/mL)80 (15.7–148)17 (5–46)6 (1.3–15)9.2 (6.4–49)9.2 (2.5–32)13.3 (2.3–32)
    Testosterone (nmol/L)11.6 (7.6–20)2 (0.8–14.6)0.6 (0.3–.9)0.3 (0.3–0.6)0.3 (0.3–0.350.3 (0.3–0.4)
    PSMA SUVmax tumor23 (8.7–32.5)17 (5–46)14 (0.8–22)20.2 (11–52)42 (15–88)27 (17–55)
    PSMA SUVmean tumor6.7 (3.4–8.4)5.7 (2.9–7.6)5.4 (0.5–6.6)6 (4.4–7.7)7.7 (4.7–12.2)6.1 (5–9.2)
    PSMA tumor volume (mL)61 (11.5–254)42 (7–273)22 (0.5–204)60 (36–293)163 (36–972)149 (22–389)
    PSMA salivary gland SUVmax14.3 (13–16.3)14.1 (10 −18)15.4 (14.3–18)14.7 (9.3–18)14.8 (11.9–18)12.8 (12.4–16)

    • Data in parentheses are IQRs.

Additional Files

Back to top

In this issue

Print
Download PDF
Article Alerts
Email Article
Citation Tools
Bookmark this article

Jump to section

Related Articles

Cited By...

More in this TOC Section

Similar Articles

Keywords