^(68)Gallium-labelled PSMA-PET/CT as a diagnostic and clinical decision-making tool in Asian prostate cancer patients following prostatectomy

Objective: Prostate cancers(PCa) in Asian individuals are molecularly distinct from those found in their Caucasian counterparts.There is no risk stratification tool for Asian men with rapid biochemical recurrence(BCR) following radical prostatectomy(Rad P). This study aims to assess the detection rate of ^(68)Ga-prostate-specific membrane antigen-positron emission tomography/computed tomography(PSMA-PET/CT) for diagnosis of clinical recurrence and as a treatment decision making tool in Asian patients with BCR post-Rad P.Methods: ^(68)Ga PSMA-PET and CT body with/without bone scan [conventional workup(CWU)] were performed in 55 Asian patients with BCR within 36 months post-Rad P. Two blinded reviewers assessed the images. Detection rates of ^(68)Ga PSMAPET/CT were evaluated, and impact on management was reviewed by comparison with CWU.Results: Median time to BCR post-Rad P was 8.1 months. Detection rate for ^(68)Ga PSMA-PET/CT was 80%(44/55). A positive scan was significantly associated with increasing prostate-specific antigen(PSA) level [odds ratio(OR) = 1.13(95% CI 1.05–1.30), P =0.017], but not with higher Gleason grade or shorter PSA doubling time. Compared to CWU, ^(68)Ga PSMA-PET/CT detected an additional 106 lesions in 33/44 patients with a positive scan, resulting in a change in management in 25/44(56.8%) patients: 10 to hormonal therapy(HT) and whole pelvis radiotherapy(RT) in addition to bed RT, and 15 to palliative HT alone.Conclusions: In the present report, we demonstrated the diagnostic and treatment decision utility of ^(68)Ga PSMA-PET/CT in Asian men with rapid BCR. Detection of small volume nodal and systemic recurrences at low PSA levels(< 1.0 ng/mL) highlights the role of the tool in assigning patients to treatment intensification with HT-RT or palliative HT in polymetastatic disease.

Transcriptomic analyses of localized prostate cancers of East Asian and North American men reveal race-specific luminal-basal and microenvironmental differences

Dear editor,Prostate cancer(PCa)remains a major healthcare burden in men globally[1].Most patients present with localized disease,and treatment is recommended based on risk classification systems like the National Comprehensive Cancer Network(NCCN)[2].However,these methods are imprecise for estimating metastasis-free survival and prostate cancer-specific mortality and thus biomarkers that can predict tumor aggression are needed[3–5].Several studies have since characterized the molecular landscape of localized PCa in White[4,5]and Black/African-American men[6],but data is lacking in Asian men.The Chinese Prostate Cancer Genome and Epigenome Atlas(CPGEA)reported on the genomic and epigenomic landscape of 208 PCa of men from China[7].Comparative analyses between the CPGEA cohort and data from The Cancer Genome Atlas(TCGA)revealed higher frequencies of Forkhead box A1(FOXA1)and chromodomain-helicase DNA-binding 1(CHD1)mutations,and lower frequencies of phosphatase and tensin homolog(PTEN)mutations and transmembrane protease serine 2-E26 transformationspecific related gene(TMPRSS2-ERG)fusion in Chinese compared with White men[7].These preliminary findings highlight the presence of race-specific differences in molecular phenotypes of PCa.