More results...

Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Abdominal Radiology, Original Research
Abdominal Radiology, Pictorial Essay
Anthropology and Dental Radiology, Original Research
Breast Imaging, Case Report
Breast Imaging, Original Research
Breast Imaging, Pictorial Essay
Breast Imaging, Review Article
Cardiopulmonary Imaging, Case Report
Cardiopulmonary Imaging, Case Series
Cardiopulmonary Imaging, Education
Cardiopulmonary Imaging, Original Research
Cardiopulmonary Imaging, Pictorial Essay
Cardiopulmonary Imaging, Review Article
Case Report
Case Report, Breast Imaging
Case Report, Cardiopulmonary Imaging
Case Report, Diagnostic Radiology
Case Report, Neuroradiology/Head and Neck Imaging
Case Report, Vascular and Interventional Radiology
Case Series
Case Series, Diagnostic Radiology
Case Series, Vascular and Interventional Radiology
DENTAL ARTICLE
Dental Radiology, Case Report
Dental Radiology, Case Series
Dental Radiology, Original Research
Diagnostic Radiology, Case Report
Diagnostic Radiology, Case Series
Diagnostic Radiology, Original Research
Diagnostic Radiology, Pictorial Essay
Diagnostic Radiology, Review Article
Editorial
Education, Original Research
Emergency, Original Research
Erratum
Gastrointestinal Imaging, Case Report
Gastrointestinal Imaging, Case Series
Gastrointestinal Imaging, Original Research
Gastrointestinal Imaging, Pictorial Essay
General and Emergency Radiology, Original Research
General and Emergency Radiology, Review Article
Genitourinary and Gynecologic Imaging, Case Report
Genitourinary and Gynecologic Imaging, Original Research
Imaging Science, Original Research
Interventional Radiology, Original Research
Letter to Editor
Musculoskeletal Imaging, Case Report
Musculoskeletal Imaging, Original Article
Musculoskeletal Imaging, Original Research
Musculoskeletal Imaging, Pictorial Essay
Musculoskeletal Imaging, Review Article
Neuroradiology , Review Article
Neuroradiology Head and Neck Imaging, Pictorial Essay
Neuroradiology, Case Report
Neuroradiology, Pictorial Essay
Neuroradiology/Head and Neck Imaging, Case Report
Neuroradiology/Head and Neck Imaging, Case Series
Neuroradiology/Head and Neck Imaging, Original Research
Neuroradiology/Head and Neck Imaging, Review Article
Neuroradiology/Spine Imaging, Original Research
Nuclear Medicine, Case Report
Nuclear Medicine, Original Research
Nuclear Medicine, Pictorial Essay
Original Article
Original Article, Neuroradiology
Original Research
Original Research Article
Original Research, Dental Radiology
Original Research, Descriptive Study
Original Research, Diagnostic Radiology
Original Research, Gastrointestinal Imaging
Original Research, Genitourinary and Gynecologic Imaging
Original Research, Musculoskeletal Imaging
Original Research, Neuroradiology/Head and Neck Imaging
Original Research, Nuclear Medicine
Original Research, Vascular and Interventional Radiology
Pediatric Imaging, Case Report
Pediatric Imaging, Pictorial Essay
PICTORIAL ESSAY
PICTORIAL REVIEW
Radiologic-Pathologic Correlation
RADIOLOGICAL-PATHOLOGICAL CORRELATION
Radiology Business, Original Research
Research Article
Review Article
Review Article, Diagnostic Radiology
Review Article, Gastrointestinal imaging
Review Article, Musculoskeletal
Review Article, Vascular and Interventional Radiology
Technical Innovation
Technical Innovation, Gastrointestinal Imaging
Ultrasound, Case Report
Ultrasound, Original Research
Ultrasound, Review Article
Vascular and International Radiology, Case Report
Vascular and Interventional Radiology, Case Report
Vascular and Interventional Radiology, Case Series
Vascular and Interventional Radiology, Original Research
Vascular and Interventional Radiology, Pictorial Essay
Vascular and Interventional Radiology, Review Article
Vascular and Interventional Radiology, Short Communication
Vascular and Interventional, Original Research

More results...

Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Abdominal Radiology, Original Research
Abdominal Radiology, Pictorial Essay
Anthropology and Dental Radiology, Original Research
Breast Imaging, Case Report
Breast Imaging, Original Research
Breast Imaging, Pictorial Essay
Breast Imaging, Review Article
Cardiopulmonary Imaging, Case Report
Cardiopulmonary Imaging, Case Series
Cardiopulmonary Imaging, Education
Cardiopulmonary Imaging, Original Research
Cardiopulmonary Imaging, Pictorial Essay
Cardiopulmonary Imaging, Review Article
Case Report
Case Report, Breast Imaging
Case Report, Cardiopulmonary Imaging
Case Report, Diagnostic Radiology
Case Report, Neuroradiology/Head and Neck Imaging
Case Report, Vascular and Interventional Radiology
Case Series
Case Series, Diagnostic Radiology
Case Series, Vascular and Interventional Radiology
DENTAL ARTICLE
Dental Radiology, Case Report
Dental Radiology, Case Series
Dental Radiology, Original Research
Diagnostic Radiology, Case Report
Diagnostic Radiology, Case Series
Diagnostic Radiology, Original Research
Diagnostic Radiology, Pictorial Essay
Diagnostic Radiology, Review Article
Editorial
Education, Original Research
Emergency, Original Research
Erratum
Gastrointestinal Imaging, Case Report
Gastrointestinal Imaging, Case Series
Gastrointestinal Imaging, Original Research
Gastrointestinal Imaging, Pictorial Essay
General and Emergency Radiology, Original Research
General and Emergency Radiology, Review Article
Genitourinary and Gynecologic Imaging, Case Report
Genitourinary and Gynecologic Imaging, Original Research
Imaging Science, Original Research
Interventional Radiology, Original Research
Letter to Editor
Musculoskeletal Imaging, Case Report
Musculoskeletal Imaging, Original Article
Musculoskeletal Imaging, Original Research
Musculoskeletal Imaging, Pictorial Essay
Musculoskeletal Imaging, Review Article
Neuroradiology , Review Article
Neuroradiology Head and Neck Imaging, Pictorial Essay
Neuroradiology, Case Report
Neuroradiology, Pictorial Essay
Neuroradiology/Head and Neck Imaging, Case Report
Neuroradiology/Head and Neck Imaging, Case Series
Neuroradiology/Head and Neck Imaging, Original Research
Neuroradiology/Head and Neck Imaging, Review Article
Neuroradiology/Spine Imaging, Original Research
Nuclear Medicine, Case Report
Nuclear Medicine, Original Research
Nuclear Medicine, Pictorial Essay
Original Article
Original Article, Neuroradiology
Original Research
Original Research Article
Original Research, Dental Radiology
Original Research, Descriptive Study
Original Research, Diagnostic Radiology
Original Research, Gastrointestinal Imaging
Original Research, Genitourinary and Gynecologic Imaging
Original Research, Musculoskeletal Imaging
Original Research, Neuroradiology/Head and Neck Imaging
Original Research, Nuclear Medicine
Original Research, Vascular and Interventional Radiology
Pediatric Imaging, Case Report
Pediatric Imaging, Pictorial Essay
PICTORIAL ESSAY
PICTORIAL REVIEW
Radiologic-Pathologic Correlation
RADIOLOGICAL-PATHOLOGICAL CORRELATION
Radiology Business, Original Research
Research Article
Review Article
Review Article, Diagnostic Radiology
Review Article, Gastrointestinal imaging
Review Article, Musculoskeletal
Review Article, Vascular and Interventional Radiology
Technical Innovation
Technical Innovation, Gastrointestinal Imaging
Ultrasound, Case Report
Ultrasound, Original Research
Ultrasound, Review Article
Vascular and International Radiology, Case Report
Vascular and Interventional Radiology, Case Report
Vascular and Interventional Radiology, Case Series
Vascular and Interventional Radiology, Original Research
Vascular and Interventional Radiology, Pictorial Essay
Vascular and Interventional Radiology, Review Article
Vascular and Interventional Radiology, Short Communication
Vascular and Interventional, Original Research

More results...

Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Abdominal Radiology, Original Research
Abdominal Radiology, Pictorial Essay
Anthropology and Dental Radiology, Original Research
Breast Imaging, Case Report
Breast Imaging, Original Research
Breast Imaging, Pictorial Essay
Breast Imaging, Review Article
Cardiopulmonary Imaging, Case Report
Cardiopulmonary Imaging, Case Series
Cardiopulmonary Imaging, Education
Cardiopulmonary Imaging, Original Research
Cardiopulmonary Imaging, Pictorial Essay
Cardiopulmonary Imaging, Review Article
Case Report
Case Report, Breast Imaging
Case Report, Cardiopulmonary Imaging
Case Report, Diagnostic Radiology
Case Report, Neuroradiology/Head and Neck Imaging
Case Report, Vascular and Interventional Radiology
Case Series
Case Series, Diagnostic Radiology
Case Series, Vascular and Interventional Radiology
DENTAL ARTICLE
Dental Radiology, Case Report
Dental Radiology, Case Series
Dental Radiology, Original Research
Diagnostic Radiology, Case Report
Diagnostic Radiology, Case Series
Diagnostic Radiology, Original Research
Diagnostic Radiology, Pictorial Essay
Diagnostic Radiology, Review Article
Editorial
Education, Original Research
Emergency, Original Research
Erratum
Gastrointestinal Imaging, Case Report
Gastrointestinal Imaging, Case Series
Gastrointestinal Imaging, Original Research
Gastrointestinal Imaging, Pictorial Essay
General and Emergency Radiology, Original Research
General and Emergency Radiology, Review Article
Genitourinary and Gynecologic Imaging, Case Report
Genitourinary and Gynecologic Imaging, Original Research
Imaging Science, Original Research
Interventional Radiology, Original Research
Letter to Editor
Musculoskeletal Imaging, Case Report
Musculoskeletal Imaging, Original Article
Musculoskeletal Imaging, Original Research
Musculoskeletal Imaging, Pictorial Essay
Musculoskeletal Imaging, Review Article
Neuroradiology , Review Article
Neuroradiology Head and Neck Imaging, Pictorial Essay
Neuroradiology, Case Report
Neuroradiology, Pictorial Essay
Neuroradiology/Head and Neck Imaging, Case Report
Neuroradiology/Head and Neck Imaging, Case Series
Neuroradiology/Head and Neck Imaging, Original Research
Neuroradiology/Head and Neck Imaging, Review Article
Neuroradiology/Spine Imaging, Original Research
Nuclear Medicine, Case Report
Nuclear Medicine, Original Research
Nuclear Medicine, Pictorial Essay
Original Article
Original Article, Neuroradiology
Original Research
Original Research Article
Original Research, Dental Radiology
Original Research, Descriptive Study
Original Research, Diagnostic Radiology
Original Research, Gastrointestinal Imaging
Original Research, Genitourinary and Gynecologic Imaging
Original Research, Musculoskeletal Imaging
Original Research, Neuroradiology/Head and Neck Imaging
Original Research, Nuclear Medicine
Original Research, Vascular and Interventional Radiology
Pediatric Imaging, Case Report
Pediatric Imaging, Pictorial Essay
PICTORIAL ESSAY
PICTORIAL REVIEW
Radiologic-Pathologic Correlation
RADIOLOGICAL-PATHOLOGICAL CORRELATION
Radiology Business, Original Research
Research Article
Review Article
Review Article, Diagnostic Radiology
Review Article, Gastrointestinal imaging
Review Article, Musculoskeletal
Review Article, Vascular and Interventional Radiology
Technical Innovation
Technical Innovation, Gastrointestinal Imaging
Ultrasound, Case Report
Ultrasound, Original Research
Ultrasound, Review Article
Vascular and International Radiology, Case Report
Vascular and Interventional Radiology, Case Report
Vascular and Interventional Radiology, Case Series
Vascular and Interventional Radiology, Original Research
Vascular and Interventional Radiology, Pictorial Essay
Vascular and Interventional Radiology, Review Article
Vascular and Interventional Radiology, Short Communication
Vascular and Interventional, Original Research
View/Download PDF

Translate this page into:

Nuclear Medicine
Pictorial Essay
2020
:10;
67
doi:
10.25259/JCIS_88_2020

Combined Intravenous Urogram and 68Ga-PSMA PET/ CT for Improved Staging and Restaging of Prostate Cancer

I-MED Radiology, The Wesley Hospital, Auchenflower, Queensland, Australia
Corresponding author: Rhiannon McBean, I-MED Radiology, The Wesley Hospital, 30 Chasely Street, Auchenflower 4066, Queensland, Australia. rhiannon.mcbean@i-med.com.au
Licence
This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: McBean R, Kumari A, McEwan L, Walters J, Wong D. Combined intravenous urogram and 68Ga-PSMA PET/CT for improved staging and restaging of prostate cancer. J Clin Imaging Sci 2020;10:67.

Abstract

Staging/restaging of prostate cancer utilizing Gallium-68 (68Ga) prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in combination with an intravenous urogram allows improved discrimination between radiotracer activity in the renal tract and small pelvic nodes or local recurrences. Within this pictorial essay, we describe the imaging protocol utilized at our institution and present cases which demonstrate the utility of this combined imaging approach.

Keywords

Prostate cancer imaging
Prostate-specific membrane antigen positron emission tomography/ computed tomography
Urogram
Prostate cancer staging
Positron emission tomography

INTRODUCTION

Staging and restaging of prostate cancer is critical in determining prognosis and strategies for disease management. Gallium-68 (68Ga) prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) has gained prominence for prostate cancer staging at Australian centers, as well as internationally. 68Ga-PSMA PET/CT has shown high sensitivity and specificity for prostate cancer recurrence in several studies.[1] However, at this time, no high-level evidence from randomized control trials is available. This situation, where adoption in clinical practice has outstripped the availability of high-level evidence, means each center offering 68Ga-PSMA PET/CT will have a protocol based on their own experiences.

At our center, 68Ga-PSMA PET/CT was introduced in June 2014. In April 2017, we updated our protocol to include a modified intravenous urogram. This method quickly became our standard practice, based on radiologist consensus that it enabled improved discrimination between radiotracer activity in the renal tract, normal variants, physiological uptake, and small pelvic nodes or local recurrences.

Imaging protocol

Our protocol commences with the administration of an intravenous (IV) bolus of 150–250 MBq 68Ga-PSMA-11 ligand complex (1.8–2.2 MBq per kilogram of body weight) and an uptake period ranging from 45 to 60 min. Administration of 25 mL of IV contrast occurs 10 min before imaging acquisition. A low-dose CT (120 KeV and 10–30 mAs) is performed first, from the calvarial vertex to proximal thighs with the patient lying supine. Concurrent PET imaging is performed of the same region, commencing proximal thighs to calvarial vertex with 8–11 bed frames (depending on the length of the patient), with an acquisition time of 3 min/bed (4 min/bed over pelvis). Finally, a second dose of 75 mL of IV contrast is administrated for the IVU and diagnostic CT, incorporating the pelvis, abdomen, chest, neck, and head. PET/CT systems are used for sequential low-dose CT, PET, and diagnostic CT image acquisition (Phillips Ingenuity TF 128 slice PET/CT, Phillips Healthcare, Amsterdam, Netherlands or GE Discovery MI DR PET/CT, GE Healthcare, Chicago, USA). Reconstructions on PET/CT emissions data are applied for attenuation correction, to minimize scatter and decay, reconstructions are also applied to diagnostic CT data. Further processing is done on appropriate workstations to create fusion images, MIPs, and plane reconstructions.

This protocol shows the contrast in the pelvic ureters and bladder 3 times over the imaging course, thus enabling a detailed assessment of high-risk structures, including both ureters with peristalsis, small nodes, and the bladder base. In early images, a small amount of contrast is seen in the pelvicalyceal systems and ureters. In mid images, contrast is seen in the pelvic arteries, the distal third of the ureters, and the bladder. In late images, contrast is seen in the aorta, inferior vena cava, pelvic arteries and veins, pelvicalyceal systems, ureters, and bladder. Ultimately, this combined method allows for differentiation based on contrast opacification and PSMA uptake. For example, a malignant node adjacent to the ureter [Figure 1] or bladder [Figure 2] will show PSMA uptake and no contrast opacification, compared to the adjacent structures which will show both PSMA uptake and contrast opacification. Similarly, tumor recurrence at a surgical site, either from previous TURP [Figure 3] or prostatectomy [Figure 4], can be differentiated from surgical changes as the tumor will show PSMA uptake and no contrast opacification. Similarly, in Figure 5, PSMA uptake observed at a suspected site of tumor recurrence was difficult to differentiate from the adjacent non-dilated ureter. In this scenario, IVU imaging allows tracing of contrast opacification down the ureters, aiding in differentiation. Further, this imaging approach is of utility in assessing prospective radioligand therapy patients, as in addition to disease restaging, kidney function is also demonstrated [Figure 6].

Figure 1:
A 79-year-old male with newly diagnosed prostate cancer (Gleason 4+5, PSA 31 ug/L). (a) IVU imaging demonstrated contrast in both ureters. (b and c) PSMA PET demonstrated a small malignant right proximal internal iliac node measuring 5 × 3.2 mm showing intense PSMA uptake with maximum SUV of 26 and no contrast opacification (a, arrow). This node lies adjacent to the right ureter posteromedially, creating a “double dot” sign (b and c, circle).
Figure 2:
A 79-year-old male with prostate cancer in the setting of biochemical recurrence following radical prostatectomy and salvage radiotherapy (Gleason 4+5, PSA 0.4 ug/L). (a) IVU imaging demonstrated small elongated left posterolateral bladder diverticulum containing contrast (arrow). (b and c) PSMA PET imaging demonstrated small intensely avid tumor recurrence measuring 8 × 6.5 mm with a maximum SUV of 6.6. Tumor recurrence was adjacent to bladder and posteromedial to bladder diverticulum which also showed intense PSMA avidity.
Figure 3:
A 77-year-old male with prostate cancer in the setting of biochemical recurrence following radical prostatectomy and pelvic node dissection (Gleason 4+3, PSA 1.2 ug/L). (a) IVU imaging demonstrated a small soft-tissue recurrence without contrast uptake measuring 10 × 8 mm in the surgical bed adjacent to the bladder (arrow). (b and c) PSMA PET imaging showed intense PSMA uptake of the recurrence with maximum SUV of 9.
Figure 4:
Staging in newly diagnosed prostate cancer (ISUP 5 + 5, PSA 27 ug/L). (a) IVU axial image shows prior TURP site demonstrating contrast uptake (arrow). (b and c) On PSMA PET primary tumor was located in PZ bilaterally in mid-prostate and demonstrated intense PSMA uptake with maximum SUV of 19 (c, circle). The TURP site also showed PSMA uptake (c, arrow).
Figure 5:
A 69-year-old male with prostate cancer in the setting of biochemical recurrence following radical prostatectomy (Gleason 4+5, PSA 0.51 ug/L). (a and b) PSMA PET images demonstrated an intensely avid region of soft tissue at prior resection site of the left seminal vesicle measuring 14 × 11.5 mm with a maximum SUV of 21 (orange arrows). This suspected recurrence was adjacent to the left ureter which was non-dilated. (c) IVU imaging allowed the non-dilated left ureter (green arrow) to be traced and thus differentiated from the tumor recurrence (orange arrow) and calcified phlebolith (green circle) also observed in the area.
Figure 6:
A 74-year-old male with prostate cancer with a 5-year history of treatment failure presenting for assessment for Lutetium-177-PSMA radioligand therapy (PSA 53 ug/L). An undiagnosed left kidney obstruction was discovered. (a) IVU imaging showed delayed left nephrogram and pyelogram contrast opacification. (b and c) PSMA PET showed tracer build-up in obstructed kidney, secondary to a large left paraaortic lymph node impinging the mid-left ureter (arrow), extensive malignant retroperitoneal, and pelvic nodes also seen. A subsequent nuclear medicine renal scan with technetium-99m mercaptoacetyltriglycine (99mTc-MAG3) showed the left differential renal function of 22%.

DISCUSSION

Normal variants, physiological uptake, and excretion of 68GaPSMA through the renal system present significant challenges in the assessment of 68Ga-PSMA PET/CT examinations. This challenge is clinically important as pelvic lymph nodes and the bladder base are common sites of metastasis.[2] Other authors have proposed alternative methods for this problem. These include the administration of furosemide concurrently with 68Ga-PSMA;[3,4] furosemide 60 min post-injection followed by delayed imaging at 180 min;[5] and early pelvic images to avoid tracer accumulation.[6] At our center, we do not utilize furosemide as this requires close attention to the patient’s hydration status and can be limited by comorbidities that contraindicate the use of diuretics. Further, methods which incorporate large delays and multiple time-points are impractical in high-throughput centers, and those which incorporate early pelvic images can result in false negatives given low lesional uptake.[6] Of note, a similar protocol to ours, combining 68Ga-PSMA PET/CT and IVU, but without the diagnostic quality CT, have been reported by Iravani et al., who retrospectively determined this approach assisted in the interpretation of 17.5% of cases.[7] We believe that our imaging protocol is likely to improve the interpretation of a similar, if not higher, number of cases as our urogram protocol contains more phases, with the added advantage of also being able to detect other pathologies on the diagnostic CT component, as reported by McEwan et al.[8] In this retrospective review of 1200 prostate cancer scans at our center, significant pathologies, often of greater clinical importance than the patient’s prostate cancer, were identified in 5.7% of examinations due to the parallel interpretation of PET and diagnostic quality CT images.

CONCLUSION

There is no consensus regarding the optimal protocol for 68Ga-PSMA PET/CT. Our method was implemented as an in-house solution to the difficulties posed by renal excretion of 68Ga-PSMA and we do not have prospective data comparing our method with alternative imaging approaches. Within this pictorial essay, we present multiple examples of cases which would have presented significant interpretation difficulties if a combined protocol had not been utilized.

Declaration of patient consent

Patient’s consent not required as the patient’s identity is not disclosed or compromised.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

  1. , , , , , , et al. Sensitivity, specificity, and predictors of positive 68Ga-prostate-specific membrane antigen positron emission tomography in advanced prostate cancer: A systematic review and meta-analysis. Eur Urol. 2016;70:926-37.
    [CrossRef] [PubMed] [Google Scholar]
  2. , , , , , , et al. The use of 68Ga-PSMA PET CT in men with biochemical recurrence after definitive treatment of acinar prostate cancer. BJU Int. 2016;118:49-55.
    [CrossRef] [PubMed] [Google Scholar]
  3. , , , , , . 68Ga-PSMA ligand PET/CT in patients with prostate cancer: How we review and report. Cancer Imaging. 2016;16:14.
    [CrossRef] [PubMed] [Google Scholar]
  4. , , , , , , et al. Frusemide aids diagnostic interpretation of 68Ga-PSMA positron emission tomography/CT in men with prostate cancer. J Med Imaging and Radiat Oncol. 2017;61:739-44.
    [CrossRef] [PubMed] [Google Scholar]
  5. , , , , , , et al. 68Ga-PSMA I&T PET/CT for assessment of prostate cancer: Evaluation of image quality after forced diuresis and delayed imaging. Eur J Radiol. 2016;26:4345-53.
    [CrossRef] [PubMed] [Google Scholar]
  6. , , , , , , et al. Evaluation of PSMA PET/CT imaging using a 68Ga-HBED-CC ligand in patients with prostate cancer and the value of early pelvic imaging. Nucl Med Commun. 2015;36:582-7.
    [CrossRef] [PubMed] [Google Scholar]
  7. , , , , , , et al. 68Ga PSMA-11 PET with CT urography protocol in the initial staging and biochemical relapse of prostate cancer. Cancer Imaging. 2017;17:31.
    [CrossRef] [PubMed] [Google Scholar]
  8. , , , . Unexpected significant findings non-related to prostate cancer identified using combined prostate-specific membrane antigen positron emission tomography/CT and diagnostic CT scan in primary staging for prostate cancer. J Med Imaging and Radiat Oncol. 2019;63:318-23.
    [CrossRef] [PubMed] [Google Scholar]
Show Sections