68 Ga-PSMA-11 and 18 F-FDG PET/CT in a Case of Ductal Adenocarcinoma of the Prostate

68Ga-PSMA PET/CT and 18F-FDG PET/CT in the diagnosis of prostatic ductal cancer

PURPOSES

To explore the characteristics of PSMA PET/CT and FDG PET/CT images in prostatic ductal adenocarcinoma (DA) patients.

METHODS

We retrospectively enrolled prostatic DA patients with PET/CT scans at Tongji Hospital from 2018 to 2022. Patients with prostatic acinar adenocarcinoma (AA) and benign pathology (BP) were enrolled by 1:1 matching. Differences in the uptake of primary and metastatic foci on PET among the groups were analyzed.

RESULTS

A total of 42 patients were enrolled: 14 in each group. In primary foci, the mean PSMA uptake in the DA group was lower than that in the AA group (14.2 ± 9.6 vs. 27.1 ± 14.3, P = 0.009) and greater than that in the BP group (14.2 ± 9.6 vs. 4.7 ± 1.3, P = 0.003). The AUCs of the DA-AA ROC curve and DA-BP ROC curve were 0.781 and 0.872, respectively. The median PSMA uptake of metastatic lymph nodes in the DA group was lower than that in the AA group (5.6 vs. 14.2, P = 0.033), with no significant difference in metastatic bone lesions (9.5 vs 19.1, P = 0.485). No significant difference was found in the FDG uptake of primary and metastatic foci between the DA and AA groups (P > 0.05).

CONCLUSION

Prostatic DA has greater PSMA uptake than BP diseases, but lower uptake in both primary foci and metastatic lymph nodes than AA on PSMA PET/CT, aiding in the differential diagnosis of DA, AA and BP diseases. Clinicians should combine traditional imaging with PSMA PET/CT to avoid underestimating the clinical stage of DA patients.

Ductal prostate cancer staging: Role of PSMA PET/CT

INTRODUCTION

To evaluate the accuracy of PSMA PET/CT in the diagnosis and clinical staging of prostatic ductal adenocarcinoma (DAC).

MATERIALS AND METHODS

Two Caucasian men 58 and 62 years old were admitted to our Department for dysuria: the patients had not familiarity for prostate cancer (PCa), PSA values were 5.6 and 2.8 ng/ml, digital rectal examination was positive, multiparametric magnetic resonance image (mpMRI) showed for both the presence of an index lesion PIRADS score 5. The patients underwent extended transperineal prostate biopsy combined with four mpMRI/TRUS fusion biopsy under sedation and antibiotic prophylaxis; biopsy histology demonstrated the presence of a mixed PCa characterized by DAC and acinar PCa (Grade Group 4/Gleason score 8). The patients underwent clinical staging performing lung and abdominal CT, bone scan and fluoride 18 (18F) PSMA PET/CT.

RESULTS

Conventional imaging was negative for distant metastases; 18F-PSMA PET/CT showed in both patients an intraprostatic lesion characterized by a standardized uptake value (SUVmax) equal to 4.6 and 4.9 in the absence of distant lesions suspicious for metastases. Following multidisciplinary evaluation, the patients underwent radical prostatectomy plus extended pelvic lymphadenectomy. Definitive specimen showed the presence in both cases of a mixed pT3bN1 PCa (ductal plus acinar pattern Grade Group 4) with positive surgical margins, neuronal invasion, and nodes metastases (5/20 and 6/24, respectively). Post-operative PSA in the two patients was 0.8 and 0.3 ng/ml, therefore patients underwent adjuvant therapy.

CONCLUSIONS

Conventional imaging and PSMA PET/CT could result inadequate in clinical staging of DAC, the use of more imaging data (i.e. mpMRI and/or F-18 FDG) could improve overall accuracy.

18 F-FDG PET/CT Imaging of Prostatic Epithelioid Hemangioendothelioma

ABSTRACT

Epithelioid hemangioendothelioma of the prostate is a rare malignant vasogenic tumor. We report a case of epithelioid hemangioendothelioma of the prostate in a 65-year-old man with lymph nodes and lung metastases on 18 F-FDG PET/CT imaging. The patient presented with symptoms of frequent and urgent urination. On 18 F-FDG PET/CT, intense FDG uptake was observed in the prostate mass along with multiple FDG-avid lesions involving the lung and lymph nodes. Histopathological examination confirmed epithelioid hemangioendothelioma in both the prostate mass and lung nodule.

High GLUT1 membrane expression and low PSMA membrane expression in Ductal Adenocarcinoma and Intraductal Carcinoma of the prostate

BACKGROUND

Both Ductal Adenocarcinoma (DAC) and Intraductal Carcinoma (IDC) of the prostate are generally associated with aggressive clinical behavior and poor prognosis, which were linked with discordant FDG positivity and low Prostate-Specific Membrane Antigen (PSMA) expression. A recent study only cited a DAC patient with low 68Ga-PSMA-11 PET/CT uptake but high 18F-FDG PET/CT uptake, however, there is lack of directly compared articles nor large data sets. Hence, the objective of this study was to investigate the expression of PSMA and GLUT1 in DAC and IDC-P patients.

METHODS

The study was conducted on 87 DAC or/and IDC-P patients without any treatment and 97 PAC patients with a Gleason score ≥8 of prostate biopsies and prostatectomy samples between August 2017 and August 2022. We performed immunohistochemical staining and scoring of various cancer component samples from the patients to reflect the protein expression levels of PSMA and GLUT1.

RESULTS

PSMA expression in PAC was significantly higher than in DAC/IDC-P (141.2 vs 78.6, p < 0.001). There was no significant difference in PSMA expression between DAC/IDC-P and adjacent PAC (78.6 vs 93.4, p = 0.166). GLUT1 expression was higher in DAC/IDC-P than in adjacent PAC (68.6 vs 51.3, p = 0.007), but was still lower than that in pure PAC (68.6 vs 93.1, p = 0.0014). It is worth noting that GLUT1 membrane expression in DAC/IDC-P was significantly increased than in pure PAC (13.0 vs 6.6, p = 0.025), and in PAC adjacent to DAC/IDC-P (13.0 vs 2.0, p < 0.001).

CONCLUSIONS

In DAC/IDC-P tissues, PSMA expression is low, while GLUT1 expression, especially GLUT1 membrane expression is high. These findings imply that DAC/IDC-P may have higher glucose metabolic and raise interest in targeting membrane GLUT1 as a novel anticancer strategy for DAC/IDC-P and other prostate cancer with high glucose metabolism.

FDG PET/CT in a Case of Pure Ductal Adenocarcinoma of the Prostate With Osteolytic Metastases and Normal PSA Level

ABSTRACT

Prostatic ductal adenocarcinoma is an uncommon aggressive subtype of prostate carcinoma. It is more likely to present with advanced stage and lower prostate-specific antigen. We describe FDG PET/CT findings in a case of pure prostatic ductal adenocarcinoma with lymph node, bone and lung metastases, normal serum prostate-specific antigen level, and elevated serum carbohydrate antigen 19-9 and carbohydrate antigen 724 levels. The primary tumor, and lymph node and bone metastases were hypermetabolic. All the bone metastases were osteolytic. The multiple lung metastases showed no significant FDG uptake, which may be due to small size.

Prostate-Specific Membrane Antigen Uptake Heterogeneity in Mixed Ductal-Acinar Adenocarcinoma of the Prostate

ABSTRACT

Prostate-specific membrane antigen (PSMA) PET findings of mixed ductal-acinar adenocarcinoma of the prostate are rarely reported. We describe 18F-PSMA-1007 PET/CT and delayed pelvic 18F-PSMA-1007 PET/MRI findings in a case of prostatic mixed ductal-acinar adenocarcinoma with multiple lymph node and bone metastases. The primary tumor showed heterogeneous PSMA uptake. The metastases in the right ilium and acetabulum showed intense PSMA uptake, but the pelvic lymph node and left iliac bone metastases showed no significant PSMA uptake. Knowledge of the intraprimary and intermetastatic heterogeneity of PSMA uptake in mixed ductal-acinar adenocarcinoma of the prostate may be helpful for accurate interpretation.