18F-fluorodeoxyglucose--positron emission tomography/computed tomography aids staging and predicts mortality in patients with muscle-invasive bladder cancer

The Added-value of Staging 18F-FDG PET/CT in the Prediction of Overall Survival in the Patients with Bladder Cancer

Objectives

This retrospective study aimed to evaluate the prognostic importance of 18F-fluorodeoxyglucose (18F-FDG)-positive pelvic lymph nodes (LNs) and extra-pelvic disease on staging 18F-FDG positron emission tomography/computed tomography (PET/CT) in patients with bladder cancer.

Methods

Bladder cancer patients who underwent staging 18F-FDG PET/CT were included in the study. Histopathologic features of tumors, therapy histories, presence of distinguishable tumors on CT and PET images, sizes and maximum standardized uptake value (SUVmax) of primary tumors, total numbers, sizes, and SUVmax of 18F-FDG-positive pelvic and extra-pelvic LNs, and total numbers and SUVmax of distant metastases (M1a/1b) were recorded. Patients were followed up until death or the last medical visit. Factors predicting overall survival were determined using Cox regression analysis.

Results

Fifty-five patients [median age: 70 (53-84), 48 (87.3%) male, 7 (12.7%) female] with bladder cancer were included in this study. Twenty-nine (52.7%) patients had 18F-FDG positive pelvic LNs, while 24 (43.7%) patients had 18F-FDG positive extra-pelvic disease. Patients with 18F-FDGpositive pelvic LNs had a higher rate of extra-pelvic disease (p=0.003). The median follow-up duration was 13.5 months. The median overall survival was 16.3 months [95% confidence interval (CI) 8.9-23.7]. The primary tumor distinguishability on PET (p=0.011) and CT (p=0.009) images, the presence of 18F-FDG-positive pelvic LNs (p<0.001) and 18F-FDG-positive extra-pelvic disease/distant metastases (M1a/M1b) (p<0.001), and the number of distant metastases (p=0.034) were associated with mortality. The 18F-FDG-positive extra-pelvic disease/distant metastases [p=0.029, odds ratio: 4.15 (95% CI 1.16-14.86)] was found to be an independent predictor of mortality in patients with bladder cancer.

Conclusion

The presence of 18F-FDG-positive extra-pelvic disease in pretreatment 18F-FDG PET/CT is an important prognostic factor in bladder cancer patients.

Evaluation of response to gemcitabine plus cisplatin-based chemotherapy using positron emission computed tomography for metastatic bladder cancer

BACKGROUND

The purpose of the present study was to examine retrospectively the contribution of 18Fluorodeoxyglucose positron emission tomography computed tomography (18FDG-PET/CT) to the evaluation of response to first-line gemcitabine plus cisplatin-based chemotherapy in patients with metastatic bladder cancer.

AIM

To evaluate the response to Gemcitabine plus Cisplatin -based chemotherapy using 18FDG-PET/CT imaging in patients with metastatic bladder cancer.

METHODS

Between July 2007 and April 2019, 79 patients underwent 18FDG-PET/CT imaging with the diagnosis of Metastatic Bladder Carcinoma (M-BCa). A total of 42 patients (38 male, 4 female) were included in the study, and all had been administered Gemcitabine plus Cisplatin-based chemotherapy. After completion of the therapy, the patients underwent a repeat 18FDG-PET/CT scan and the results were compared with the PET/CT findings before chemotherapy according to European Organisation for the Research and treatment of cancer criteria. Mean age was 66.1 years and standard deviation was 10.7 years (range: 41-84 years).

RESULTS

Of the patients, seven (16.6%) were in complete remission, 17 (40.5%) were in partial remission, six (14.3%) had a stable disease, and 12 (28.6%) had a progressive disease. The overall response rate was 57.1 percent.

CONCLUSION

18FDG-PET/CT can be considered as a successful imaging tool in evaluating response to first-line chemotherapy for metastatic bladder cancer. Anatomical and functional data obtained from PET/CT scans may be useful in the planning of secondline and thirdline chemotherapy.

Comparison of Conventional Imaging and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnostic Accuracy of Staging in Patients with Intrahepatic Cholangiocarcinoma

We aimed to examine the accuracy of tumor staging of intrahepatic cholangiocarcinoma (ICC) by using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET-CT). From January 2001 to December 2021, 202 patients underwent PET-CT, CT, and MRI for the initial staging of ICC in two institutions. Among them, 102 patients had undergone surgical treatment. Ninety patients who had a histopathological diagnosis of ICC were retrospectively reviewed. The sensitivity and specificity of 18F-FDG PET-CT, CT, and magnetic resonance imaging (MRI) in detecting tumors, satellite focus, vascular invasion, and lymph node metastases were analyzed. Ninety patients with histologically diagnosed ICC were included. PET-CT demonstrated no statistically significant advantage over CT and MR in the diagnosis of multiple tumors and macrovascular invasion, and bile duct invasion. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET-CT in lymph node metastases were 84%, 86%, 91%, 84%, and 86%, respectively. PET-CT revealed a significantly higher accuracy compared to CT or MRI (86%, 67%, and 76%, p < 0.01, respectively) in the diagnosis of regional lymph node metastases. The accuracy of tumor staging by PET-CT was higher than that by CT/MRI (PET-CT vs. CT vs. MRI: 68/90 vs. 47/90 vs. 51/90, p < 0.05). 18F-FDG PET-CT had sensitivity and specificity values for diagnosing satellite focus and vascular and bile duct invasion similar to those of CT or MRI; however, PET-CT showed higher accuracy in diagnosing regional lymph node metastases. 18F-FDG PET-CT exhibited higher tumor staging accuracy than that of CT/MRI. Thus, 18FDG PET-CT may support tumor staging in ICC.

PET/CT in Bladder Cancer: An Update

In the urinary tract, bladder cancer is the most common malignancy. It is a heterogenous cancer type with approximately 30% presenting as muscle invasive bladder cancer with a high risk of metastatic spread associated with risk of death from distant metastases. The other 70% of bladder cancer patients present with superficial tumors with tendency of recurrence but in general not life-threatening. Like in other malignancies, accurate and precise staging of bladder cancer is one of the mainstays at the time of diagnosis to select the optimal treatment for each patient. The detection of metastatic spread is of utmost importance for selection of treatment strategy. Hybrid imaging med with FDG PET/CT is widely used in the clinical management of a variety of malignancies. FDG PET/CT is increasingly used for primary staging of muscle invasive bladder cancer and for detection of recurrence after radical cystectomy. Few studies have used FDG PET/CT for response evaluation of neoadjuvant, induction chemotherapy or immunotherapy. Furthermore, small studies have tested non-FDG PET agents with little or no urinary excretions of the tracer. This review provides an update on PET/CT in bladder cancer.

Complete metabolic response with [18 F]fluorodeoxyglucose-positron emission tomography/computed tomography predicts survival following induction chemotherapy and radical cystectomy in clinically lymph node positive bladder cancer

OBJECTIVE

To determine whether repeated [¹⁸ F]fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET-CT) scans can predict increased cancer-specific survival (CSS) after induction chemotherapy followed by radical cystectomy (RC).

PATIENTS AND METHODS

Between 2007 and 2018, 86 patients with clinically lymph node (LN)-positive bladder cancer (T1-T4, N1-N3, M0-M1a) were included and underwent a repeated FDG-PET-CT during cisplatin-based induction chemotherapy. The 71 patients that had a response to chemotherapy underwent RC. Response to chemotherapy was evaluated in LNs through repeated FDG-PET-CT and stratified as partial response or complete response using three different methods: maximum standardised uptake value (SUV_max ), adapted Deauville criteria, and total lesion glycolysis (TLG). Progression-free survival (PFS) and CSS were analysed for all three methods by Cox regression analysis.

RESULTS

After a median follow-up of 40 months, 15 of the 71 patients who underwent RC had died from bladder cancer. Using SUV_max and the adapted Deauville criteria, multivariable Cox regression analyses adjusting for age, clinical tumour stage and LN stage showed that complete response was associated with increased PFS (hazard ratio [HR] 3.42, 95% confidence interval [CI] 1.20-9.77) and CSS (HR 3.30, 95% CI 1.02-10.65). Using TLG, a complete response was also associated with increased PFS (HR 5.17, 95% CI 1.90-14.04) and CSS (HR 6.32, 95% CI 2.06-19.41).

CONCLUSIONS

Complete metabolic response with FDG-PET-CT predicts survival after induction chemotherapy followed by RC in patients with LN-positive bladder cancer and comprises a novel tool in evaluating response to chemotherapy before surgery. This strategy has the potential to tailor treatment in individual patients by identifying significant response to chemotherapy, which motivates the administration of a full course of induction chemotherapy with a higher threshold for suspending treatment due to toxicity and side-effects.

Role of PET/CT in muscle-invasive bladder cancer

The purpose of this study covered the diagnostic accuracy and usefulness of positron emission tomography/computed tomography (PET/CT) imaging in muscle invasive bladder cancer patients through previously published literature. Through 30 September, 2019, the PubMed database was searched for eligible articles that evaluated PET/CT imaging in bladder cancer patients. In general, FDG PET/CT, the most commonly used PET/CT imaging, does not show good performance for the detection of primary lesions; however, according to the literature it could accurately assess pelvic lymph node (LN) status better than other imaging technologies and it was especially helpful in determining extra-pelvic recurrences. More recently, non-FDG PET/CT imaging, such as C-11 acetate and C-11 choline, has been introduced. Although further research is required, preliminary results show the potential of these techniques to overcome the drawbacks of FDG. This concise study will overview the role of PET/CT when treating muscle-invasive bladder cancer (MIBC).

The Role of 18F-FDG PET/CT in Guiding Precision Medicine for Invasive Bladder Carcinoma

Bladder cancer (BC) is the 10th most common cancer worldwide. Approximately one quarter of patients with BC have muscle-invasive disease (MIBC). Muscle-invasive disease carries a poor prognosis and choosing the optimal treatment option is critical to improve patients’ outcomes. Ongoing research supports the role of 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography (18F-FDG PET) in guiding patient-specific management decisions throughout the course of MIBC. As an imaging modality, 18F-FDG PET is acquired simultaneously with either computed tomography (CT) or MRI to offer a hybrid approach combining anatomical and metabolic information that complement each other. At initial staging, 18F-FDG PET/CT enhances the detection of extravesical disease, particularly in patients classified as oligometastatic by conventional imaging. 18F-FDG PET/CT has value in monitoring response to neoadjuvant and systemic chemotherapy, as well as in localizing relapse after treatment. In the new era of immunotherapy, 18F-FDG PET/CT may also be useful to monitor treatment efficacy as well as to detect immune-related adverse events. With the advent of artificial intelligence techniques such as radiomics and deep learning, these hybrid medical images can be mined for quantitative data, providing incremental value over current standard-of-care clinical and biological data. This approach has the potential to produce a major paradigm shift toward data-driven precision medicine with the ultimate goal of personalized medicine. In this review, we highlight current literature reporting the role of 18F-FDG PET in supporting personalized management decisions for patients with MIBC. Specific topics reviewed include the incremental value of 18F-FDG PET in prognostication, pre-operative planning, response assessment, prediction of recurrence, and diagnosing drug toxicity.

Diagnostic Value of 18F-fluorodeoxyglucose Positron Emission Tomography with Computed Tomography for Lymph Node Staging in Patients with Upper Tract Urothelial Carcinoma

BACKGROUND

Presence of lymph node metastases (LNM) is an important prognostic factor for cancer-specific survival (CSS) in patients with upper tract urothelial carcinoma (UTUC). In various neoplasms, ¹⁸F-fluorodeoxyglucose positron emission tomography with computed tomography (FDG-PET/CT) is an established modality for preoperative lymph node (LN) staging. In UTUC, the diagnostic value of FDG-PET/CT for LN staging is unknown.

OBJECTIVE

To determine the diagnostic value of FDG-PET/CT for LN staging in patients with UTUC.

DESIGN, SETTING, AND PARTICIPANTS

Data of 152 patients with UTUC who underwent FDG-PET/CT followed by surgical treatment in eight centers between 2007 and 2017 were retrospectively collected. Patients receiving neoadjuvant chemotherapy were excluded.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

FDG-PET/CT results were compared with histopathology after lymph node dissection (LND). Recurrence-free survival (RFS), CSS, and overall survival (OS) were analyzed using Kaplan-Meier estimates, and compared for patients with and without suspicious LNs on FDG-PET/CT.

RESULTS AND LIMITATIONS

We included 117 patients, of whom 62 underwent LND. Seventeen patients had LNM at histopathological evaluation. Sensitivity and specificity of FDG-PET/CT for diagnosis of LNM were 82% (95% confidence interval [CI]: 57-96) and 84% (95% CI: 71-94), respectively. RFS was significantly worse in patients with LN-positive FDG-PET/CT than in those with LN-negative FDG-PET/CT (p=0.03). CSS (p=0.11) and OS (p=0.5) were similar between groups. This study is limited by its retrospective design and by its sample size. Our results warrant further validation.

CONCLUSIONS

FDG-PET/CT has 82% sensitivity and 84% specificity for the detection of LNM in patients with UTUC. Presence of suspicious LNs on FDG-PET/CT is associated with worse RFS.

PATIENT SUMMARY

In patients with upper tract urothelial cancer, positron emission tomography with computed tomography (PET/CT) scans can detect lymph node metastases with noteworthy accuracy. Presence of suspicious lymph nodes on ¹⁸F-fluorodeoxyglucose PET/CT is associated with worse recurrence-free survival.

A glance at imaging bladder cancer

Purpose

Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons.

Methods

Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as "bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging".

Results

A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using ¹⁸F-FDG or ¹¹C-choline and recently PET/MRI using ¹⁸F-FDG also play a prominent role in detection of BCa.

Conclusion

For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted.

PET-CT and PET-MR in urological cancers other than prostate cancer: An update on state of the art

Hybrid positron emission tomography with computed tomography (PET/CT) and magnetic resonance imaging (PET/MRI) have enabled the combination of morphologic and functional imaging with the promise of providing better information in guiding therapy. Further advance has been made in the past decade with the development of newer radiotracers and optimization of the technical aspects. We performed a search in PubMed, Scopus, and Google Scholar for peer-reviewed literature concerning the advances and newer developments in the imaging of nonprostate urologic cancers between 2005 and 2017. This review aims at summarizing the current evidence on PET imaging in nonprostate urologic cancers and their impact on the diagnosis, staging, prognostication, response assessment, and restaging of these malignancies. However, much of the evidence is still in infancy and has not been incorporated into routine management or the practice guidelines of National Comprehensive Cancer Network or European Society for Medical Oncology (ESMO).

Update on advances in molecular PET in urological oncology

Integrated positron emission tomography/computed tomography (PET/CT) with 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG) has emerged as a powerful tool for the combined metabolic and anatomic evaluation of many cancers. In urological oncology, however, the use of (18)F-FDG has been limited by a generally low tumor uptake, and physiological excretion of FDG through the urinary system. (18)F-FDG PET/CT is useful when applied to specific indications in selected patients with urological malignancy. New radiotracers and positron emission tomography/magnetic resonance imaging (PET/MRI) are expected to further improve the performance of PET in uro-oncology.

[Positron-emission tomography in urooncology]

The use of positron emission tomography (PET) is an established method for the diagnosis of urological malignancies. Several tracers are currently available to obtain metabolic information or directly detect molecular targets. While (18)F-FDG-PET is recognized in current guidelines for the staging of seminoma, PET is not used in clinical routine in renal malignancies due to the lack of specific tracers. Despite initial promising results in bladder cancer, no relevant additional diagnostic value with PET using (18)F-FDG or choline-based tracers could be obtained in most patients and therefore should be used with caution or only within clinical trials. In prostate cancer, however, after development of new tracers that, for example, target prostate-specific membrane antigen (PSMA), a paradigm shift in imaging can be recognized. Here, (68)Ga-PSMA-PET might be included in the future as part of standard imaging work-up.

Recurrent ureteric transitional cell carcinoma presenting as an isolated brain metastasis: incidental detection with 18F-FDG PET/CT

Brain metastasis from transitional cell carcinoma (TCC) of the ureter is extremely rare. Here we present a case of a 73-year-old woman, a follow-up case of ureteric TCC in whom isolated brain metastasis was incidentally detected at follow-up 18F-FDG PET/CT. This was corroborated with MRI. She underwent excision of the lesion, and histopathology confirmed metastatic TCC.

Evolving role of positron emission tomography (PET) in urological malignancy

We present a review on the increasing indications for the use of positron emission tomography (PET) in uro-oncology. In this review we describe the details of the different types of PET scans, indications for requesting PET scans in specific urological malignancy and the interpretation of the results.

PET/Computed Tomography in Renal, Bladder, and Testicular Cancer

Imaging plays an important role in the clinical management of cancer patients. Hybrid imaging with PET/computed tomography (CT) is having a broad impact in oncology, and in recent years PET/CT is beginning to have an impact in urooncology. In both bladder and renal cancers, there is a need to study the efficacy of other tracers than F-18 fluorodeoxyglucose (FDG), particularly tracers with limited renal excretion. Thus, new tracers are being introduced. This review focuses on the clinical role of FDG and other PET agents in renal, bladder, and testicular cancers.

Detecting Metastatic Bladder Cancer Using (18)F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography

PURPOSE

The purpose of this study was to retrospectively investigate the contribution of (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG-PET/CT) to detection of metastatic bladder cancer.

MATERIALS AND METHODS

The present study included 79 patients (69 men and 10 women) undergoing (18)F-FDG-PET/CT upon suspicion of metastatic bladder cancer between July 2007 and April 2013. The mean age was 66.1 years with a standard deviation of 10.7 years (range, 21 to 85 years). Patients were required to fast for 6 hours prior to scanning, and whole-body PET scanning from the skull base to the upper thighs was performed approximately 1 hour after intravenous injection of 555 MBq of (18)F-FDG. Whole body CT scanning was performed in the cranio-caudal direction. FDG-PET images were reconstructed using CT data for attenuation correction. Suspicious recurrent or metastatic lesions were confirmed by histopathology or clinical follow-up.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of (18)F-FDG-PET/CT were 89%, 78%, 90%, 75%, and 86%, respectively.

CONCLUSION

(18)F-FDG-PET/CT can detect metastases with high sensitivity and positive predictive values in patients with metastatic bladder carcinoma.

[(18)F]Fluorodeoxyglucose - positron emission tomography/computed tomography improves staging in patients with high-risk muscle-invasive bladder cancer scheduled for radical cystectomy

OBJECTIVE

The aim of this study was to evaluate the clinical use of [(18)F]fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in addition to conventional preoperative radiological investigations in a defined group of patients with high-risk muscle-invasive bladder cancer.

MATERIALS AND METHODS

In total, 103 patients with high-risk muscle-invasive bladder cancer defined as stage T3/T4 disease or as stage T2 with hydronephrosis or high-risk histological features, who were provisionally scheduled to undergo cystectomy, were prospectively recruited to the study. The patients were referred to FDG-PET/CT in addition to standard preoperative investigation with computed tomography (CT). The final treatment decision was reached at a multidisciplinary conference based on all available information including the FDG-PET/CT findings.

RESULTS

Compared to CT alone, FDG-PET/CT provided more supplemental findings suggesting malignant manifestations in 48 (47%) of the 103 patients. The additional FDG-PET/CT findings led to an altered provisional treatment plan in 28 out of 103 patients (27%), detection of disseminated bladder cancer and subsequent cancellation of the initially intended cystectomy in 16 patients, and identification of disseminated disease and treatment with induction chemotherapy before radical cystectomy in 12 patients.

CONCLUSIONS

Preoperative FDG-PET/CT changed the treatment plan for a considerable proportion (27%) of the present patients. Accordingly, such examination can potentially improve the preoperative staging of cystectomy patients with high-risk features, and may also reduce the number of futile operations in patients with advanced disease who are beyond cure.

Efficacy of 18F-fluorodeoxyglucose-positron emission tomography/computed tomography in restaging muscle-invasive bladder cancer following radical cystectomy

The aim of the present study was to retrospectively evaluate the contribution and effectiveness of ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) scans in the restaging of patients following radical cystectomy due to muscle-invasive bladder carcinoma (MIBC). A total of 51 patients (45 males and six females) who underwent radical cystectomy due to invasive bladder cancer, and had an ¹⁸F-FDG-PET/CT scan for restaging between July 2007 and April 2013, were included in the present study. The mean age was 62.3±9.79 years (range, 40–82 years). Patients underwent a six-hour fast prior to scanning, and whole-body PET scanning from the skull base to the upper thighs was performed ~1 h after the intravenous injection of 555 MBq ¹⁸F-FDG. Whole-body CT scanning was performed in a cranio-caudal direction. ¹⁸F-FDG-PET images were reconstructed using CT data for attenuation correction. Histopathology or clinical follow-up was used to confirm any suspicious recurrent or metastatic lesions. The results for sensitivity, specificity, positive predictive value (PPV), negative predictive value and accuracy of ¹⁸F-FDG-PET/CT were 92, 83, 94, 77 and 90%, respectively. In conclusion, ¹⁸F-FDG-PET/CT efficiently detects local recurrence and distant metastases with high sensitivity and PPV in the restaging of patients who underwent radical cystectomy due to invasive bladder cancer. This procedure could play an important role in rendering decisions regarding radiotherapy or chemotherapy and post-operative follow-up, and could influence the entire decision-making process.