Added Clinical Value of 18F-FDG-PET/CT to Stage Patients With High-Risk Non-Muscle Invasive Bladder Cancer Before Radical Cystectomy.

INTRODUCTION AND OBJECTIVES: 18F-fluorodeoxyglucose positron-emission tomography-computed tomography (FDG-PET/CT) is increasingly used in the preoperative staging of patients with muscle-invasive bladder cancer. The clinical added value of FDG-PET/CT in high-risk non-muscle invasive bladder cancer (NMIBC) is unknown. In this study, the value of FDG-PET/CT in addition to contrast enhanced (CE)-CT was evaluated in high-risk NMIBC before radical cystectomy (RC). MATERIALS AND METHODS: This is a retrospective analysis of consecutive patients with high risk and very-high risk urothelial NMIBC scheduled for RC in a tertiary referral center between 2011 and 2020. Patients underwent staging with CE-CT (chest and abdomen/pelvis) and FDG-PET/CT. We assessed the clinical disease stage before and after FDG-PET/CT and the treatment recommendation based on the stage before and after FDG-PET/CT. The accuracy of CT and FDG-PET/CT for identifying metastatic disease was defined by the receiver-operating curve using a reference-standard including histopathology/cytology (if available), imaging and follow-up. RESULTS: A total of 92 patients were identified (median age: 71 years). In 14/92 (15%) patients, FDG-PET/CT detected metastasis (12 suspicious lymph nodes and 4 distant metastases). The disease stage changed in 11/92 (12%) patients based on additional FDG-PET/CT findings. FDG-PET/CT led to a different treatment in 9/92 (10%) patients. According to the reference standard, 25/92 (27%) patients had metastases. The sensitivity, specificity and accuracy of FDG-PET/CT was 36%, 93% and 77% respectively, versus 12%, 97% and 74% of CE-CT only. The area under the ROC curve was 0.643 for FDG-PET/CT and 0.545 for CT, P = .036. CONCLUSION: The addition of FDG-PET/CT to CE-CT imaging changed the treatment in 10% of patients and proved to be a valuable diagnostic tool in a selected subgroup of NMIBC patients scheduled for RC.

Prevalence, Treatment, and Prognosis of Tumor Thrombi in Renal Cell Carcinoma.

Background: Renal cell carcinoma (RCC) can be complicated by a venous tumor thrombus (TT), of which the optimal management is unknown. Objectives: This study sought to assess the prevalence of TT in RCC, its current management, and its association with venous thromboembolism (VTE), arterial thromboembolism (ATE), major bleeding (MB), and mortality. Methods: Patients diagnosed with RCC between 2010 and 2019 in our hospital were included and followed from RCC diagnosis until 2 years after, or until an outcome of interest (VTE, ATE, and MB) or death occurred, depending on the analysis. Cumulative incidences were estimated with death as a competing risk. Cause-specific hazard models were used to identify predictors and the prognostic impact. Results: Of the 647 patients, 86 had a TT (prevalence 13.3%) at RCC diagnosis, of which 34 were limited to the renal vein, 37 were limited to the inferior vena cava below the diaphragm, and 15 extended above the diaphragm; 20 patients started therapeutic anticoagulation and 45 underwent thrombectomy with/without anticoagulation. During follow-up (median 24.0 [IQR: 7.0-24.0] months), 17 TT patients developed a VTE, 0 developed an ATE, and 11 developed MB. TT patients were more often diagnosed with VTE (adjusted HR: 6.61; 95% CI: 3.18-13.73) than non-TT patients, with increasing VTE risks in more proximal TT levels. TT patients receiving anticoagulation still developed VTE (HR: 0.56; 95% CI: 0.13-2.48), at the cost of more MB events (HR: 3.44; 95% CI: 0.95-12.42) compared with those without anticoagulation. Conclusions: Patients with RCC-associated TT were at high risk of developing VTE. Future studies should establish which of these patients benefit from anticoagulation therapy.

Phase 1 Study of Chemoradiotherapy Combined with Nivolumab ± Ipilimumab for the Curative Treatment of Muscle-invasive Bladder Cancer.

BACKGROUND: Muscle-invasive bladder cancer (MIBC) has a poor prognosis. Chemoradiotherapy (CRT) in selected patients has comparable results to radical cystectomy. Results of neoadjuvant immune checkpoint inhibitors (ICIs) before radical cystectomy are promising. We hypothesize that ICI concurrent to CRT (iCRT) is safe and may improve treatment outcomes. OBJECTIVE: To determine the safety of iCRT for MIBC. DESIGN, SETTING, AND PARTICIPANTS: This multicenter, phase 1b, open-label, dose-escalation study determined the safety of CRT with three ICI regimens in patients with nonmetastatic (T2-4aN0-1) MIBC. Twenty-six patients received mitomycin C/capecitabine and 20 × 2.75 Gy to the bladder. Tolerability was evaluated in a cohort of up to ten patients. If two or fewer out of the first six patients or three or fewer of ten patients experienced dose-limiting toxicity (DLT), accrual continued in the next cohort. INTERVENTION: Patients received nivolumab 480 mg (NIVO480), nivolumab 3 mg/kg and ipilimumab 1 mg/kg (NIVO3 + IPI1), or nivolumab 1 mg/kg and ipilimumab 3 mg/kg (IPI3 + NIVO1). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was safety. Secondary objectives were response rate, disease-free survival, metastatic-free survival (MFS), and overall survival (OS). RESULTS AND LIMITATIONS: In the NIVO480 cohort, no patients experienced DLT. The NIVO3 + IPI1 2 patients experienced DLT, thrombocytopenia (grade 4), and asystole (grade 5). IPI3 + NIVO1 was discontinued after three out of six patients experienced DLT. Clinically significant adverse events (AEs) of grade ≥3 occurred in zero, three, and five patients in the NIVO480, NIVO3 + IPI1, and IPI3 + NIVO1 groups, respectively. The most common AEs were immune related and gastrointestinal. MFS and OS were 90% at 2 yr for NIVO480 and 90% at 1 yr for NIVO3 + IPI1. Limitations include the absence of a centralized pathology and radiology review, and a lack of biomarker analysis. CONCLUSIONS: In this dose-finding study of iCRT, the regimens of nivolumab monotherapy and nivolumab 3 mg/kg with ipilimumab 1 mg/kg have acceptable toxicity. PATIENT SUMMARY: We tested the safety of a new bladder-sparing treatment modality for muscle-invasive bladder cancer patients, combining immune checkpoint inhibitors simultaneously with chemoradiotherapy. We report that two regimens, nivolumab monotherapy and nivolumab 3 mg/kg with ipilimumab 1 mg/kg, are safe and can be used in phase 3 trials.

Evaluation of the Hybrid Tracer Indocyanine Green- 99m Tc-Nanocolloid for Sentinel Node Biopsy in Bladder Cancer-A Prospective Pilot Study.

RATIONALE: In muscle-invasive bladder cancer (MIBC), lymph node invasion has proven to be an independent predictor of disease recurrence and cancer-specific survival. We evaluated the feasibility of targeting the sentinel node (SN) for biopsy in MIBC patients using the hybrid tracer indocyanine green (ICG)- 99m Tc-nanocolloid for simultaneous radioguidance and fluorescence guidance. METHODS: Twenty histologically confirmed cN0M0 MIBC patients (mean age, 63.3 years; range, 30-82 years), scheduled for radical cystectomy with SN biopsy and extended pelvic lymph node dissection (ePLND), were prospectively included. Twelve patients were operated on following neoadjuvant chemotherapy. The patients received lymphoscintigraphy as well as SPECT/CT after 4 transurethral injections of ICG- 99m Tc-nanocolloid (mean, 208 MBq; range, 172-229 MBq) around the tumor/scar in the detrusor muscle of the bladder on the day before radical cystectomy. Sentinel node resection was performed under radioguidance and fluorescence guidance. RESULTS: Nineteen patients could be analyzed. On preoperative imaging, SNs could be identified in 10 patients (53%; mean, 1.6 SN/patient), which revealed drainage pathways outside the ePLND in 20% of the patients. Interesting to note is that 2 patients (10%) with preoperative nonvisualization displayed fluorescent and radioactive SNs during surgery. Location of the primary tumor near the left lateral side of the bladder seemed to be a factor for nonvisualization. Nodal harvesting with ePLND varied among patients (mean, 23.3). Histopathology confirmed tumor-positive nodes in 4 (21%) of all patients. In the 2 patients where an SN could be identified, the ePLND specimens were tumor-negative. All patients with tumor-positive nodes had advanced disease (stage III). CONCLUSION: Sentinel node biopsy in bladder cancer using the hybrid tracer ICG- 99m Tc-nanocolloid is feasible, and preoperative imaging is predictive for the ability to perform SN biopsy in 83% of the patients who displayed an SN. In patients with a successful preoperative SN mapping using lymphoscintigraphy and SPECT/CT, the intraoperative SN guidance and detection were effective, even outside the ePLND area. As such, this study underscores the critical role that preoperative imaging plays in challenging image-guided surgery applications.

Staging 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Changes Treatment Recommendation in Invasive Bladder Cancer.

Given the high risk of systemic relapse following initial therapy for muscle-invasive bladder cancer (MIBC), improved pretreatment staging is needed. We evaluated the incremental value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) after standard conventional staging, in the largest cohort of MIBC patients to date. This is a retrospective analysis of 711 consecutive patients with invasive urothelial bladder cancer who underwent staging contrast-enhanced CT (chest and abdomen) and FDG-PET/CT in a tertiary referral center between 2011 and 2020. We recorded the clinical stage before and after FDG-PET/CT and treatment recommendation based on the stage before and after FDG-PET/CT. Clinical stage changed after FDG-PET/CT in 184/711 (26%) patients. Consequently, the recommended treatment strategy based on imaging changed in 127/711 (18%) patients. In 65/711 (9.1%) patients, potential curative treatment changed to palliative treatment because of the detection of distant metastases by FDG-PET/CT. Fifty (7.0%) patients were selected for neoadjuvant/induction chemotherapy based on FDG-PET/CT. Moreover, FDG-PET/CT detected lesions suspicious for second primary tumors in 15%; a second primary malignancy was confirmed in 28/711 (3.9%), leading to treatment change in ten (1.4%) patients. Contrarily 57/711 (8.1%) had false positive secondary findings. In conclusion, FDG-PET/CT provides important incremental staging information, which potentially influences clinical management in 18% of MIBC patients, but leads to false positive results as well. PATIENT SUMMARY: In this report, we investigated the impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scanning on treatment of bladder cancer patients. We found that FDG-PET/CT potentially influences the treatment of almost one-fifth of patients. We therefore suggest performing FDG-PET/CT as part of bladder cancer staging.

Multi-wavelength fluorescence imaging with a da Vinci Firefly-a technical look behind the scenes.

The field of fluorescence-guided surgery builds on colored fluorescent tracers that have become available for different clinical applications. Combined use of complementary fluorescent emissions can allow visualization of different anatomical structures (e.g. tumor, lymphatics and nerves) in the same patient. With the aim to assess the requirements for multi-color fluorescence guidance under in vivo conditions, we thoroughly characterized two FDA-approved laparoscopic Firefly camera systems available on the da Vinci Si or da Vinci Xi surgical robot. In this process, we studied the cameras' performance with respect to the photophysical properties of the FDA-approved dyes Fluorescein and ICG. Our findings indicate that multi-wavelength fluorescence imaging of Fluorescein and ICG is possible using clinical-grade fluorescence laparoscopes, but critical factors for success include the photophysical dye properties, imaging system performance and the amount of accumulated dye. When comparing the camera performance, the Xi system provided more effective excitation (adaptions in the light source) and higher detection sensitivity (chip-on-a-tip and/or enhanced image processing) for both Fluorescein and ICG. Both systems can readily be used for multi-wavelength fluorescence imaging of Fluorescein and ICG under clinically relevant conditions. With that, another step has been made towards the routine implementation of multi-wavelength image-guided surgery concepts.

18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in muscle-invasive bladder cancer.

PURPOSE OF REVIEW: In this narrative review, we assessed the role of F-fluoro-2-deoxy-D-glucose-positron emission tomography/CT (FDG-PET/CT) in preoperative staging and response evaluation of neoadjuvant chemotherapy in muscle-invasive bladder carcinoma (MIBC), and to assess its incremental value to contrast-enhanced (CE)CT and MRI in terms of patient management at initial diagnosis and detection of recurrence. RECENT FINDINGS: A literature search in PubMed yielded 46 original reports, of which 15 compared FDG-PET/CT with CECT and one with MRI. For primary tumor assessment, FDG-PET/CT proved not accurate enough (13 reports; n = 7-70). For lymph node assessment, sensitivity of FDG-PET/CT is superior to CT with comparable specificity in 19 studies (n = 15-233). For detection of distant metastases, data from eight studies (n = 43-79) suggests that FDG-PET/CT is accurate, although comparative studies are lacking. Limited evidence (four studies, n = 19-50) suggests that FDG-PET/CT is not accurate for response evaluation of neoadjuvant chemotherapy. FDG-PET/CT incited change(s) in patient management in 18-68% of patients (five reports; n = 57-103). For detection of recurrence, seven studies (n = 29-287) indicated that FDG-PET/CT is accurate. SUMMARY: Most studies evaluated FDG-PET/CT for lymph node assessment and reported higher sensitivity than CT, with comparable specificity. FDG-PET/CT showed incremental value to CECT for recurrence and often incited change(s) in patient management.

An ex vivo Tissue Culture Model for the Assessment of Individualized Drug Responses in Prostate and Bladder Cancer.

Urological malignancies, including prostate and bladder carcinoma, represent a major clinical problem due to the frequent occurrence of therapy resistance and the formation of incurable distant metastases. As a result, there is an urgent need for versatile and predictive disease models for the assessment of the individualized drug response in urological malignancies. Compound testing on ex vivo cultured patient-derived tumor tissues could represent a promising approach. In this study, we have optimized an ex vivo culture system of explanted human prostate and bladder tumors derived from clinical specimens and human cancer cell lines xenografted in mice. The explanted and cultured tumor slices remained viable and tissue architecture could be maintained for up to 10 days of culture. Treatment of ex vivo cultured human prostate and bladder cancer tissues with docetaxel and gemcitabine, respectively, resulted in a dose-dependent anti-tumor response. The dose-dependent decrease in tumor cells upon administration of the chemotherapeutic agents was preceded by an induction of apoptosis. The implementation and optimization of the tissue slice technology may facilitate the assessment of anti-tumor efficacies of existing and candidate pharmacological agents in the complex multicellular neoplastic tissues from prostate and bladder cancer patients. Our model represents a versatile "near-patient" tool to determine tumor-targeted and/or stroma-mediated anti-neoplastic responses, thus contributing to the field of personalized therapeutics.

Multispectral-Fluorescence Imaging as a Tool to Separate Healthy from Disease-Related Lymphatic Anatomy During Robot-Assisted Laparoscopy.

To reduce the invasive nature of extended pelvic lymph node (LN) dissections in prostate cancer, we have developed a multispectral-fluorescence guidance approach that enables discrimination between prostate-draining LNs and lower-limb-draining LNs. Methods: In 5 pigs, multispectral-fluorescence guidance was used on da Vinci Si and da Vinci Xi robots. The animals received fluorescein into the lower limb and indocyanine green-nanocolloid into the prostate. Results: Fluorescein was detected in 29 LNs (average of 3.6 LNs/template), and indocyanine green-nanocolloid was detected in 12 LNs (average of 1.2 LNs/template). Signal intensities appeared equal for both dyes, and no visual overlap in lymphatic drainage patterns was observed. Furthermore, fluorescein supported both the identification of leakage from damaged lymphatic structures and the identification of ureters. Conclusion: We demonstrated that the differences in lymphatic flow pattern between the prostate and lower limbs could be intraoperatively distinguished using multispectral-fluorescence imaging.