Bladder cancer imaging: an update

Eligibility and Radiologic Assessment in Adjuvant Clinical Trials in Bladder Cancer

Objective

To harmonize eligibility criteria and radiographic disease assessments in clinical trials of adjuvant therapy for muscle-invasive bladder cancer (MIBC).

Methods

National experts in bladder cancer clinical trial research, including medical and urologic oncologists, radiologists, biostatisticians, and patient advocates, convened at a public workshop on November 28, 2017, to discuss eligibility, radiographic entry criteria, and assessment of disease recurrence in adjuvant clinical trials in patients with MIBC.

Results

The key workshop conclusions for adjuvant MIBC clinical trials included the following points: (1) patients with urothelial carcinoma with divergent histologic differentiation should be allowed to enroll; (2) neoadjuvant chemotherapy is defined as at least 3 cycles of neoadjuvant cisplatin-based combination chemotherapy; (3) patients with muscle-invasive, upper-tract urothelial carcinoma should be included in adjuvant trials of MIBC; (4) patients with severe renal insufficiency can enroll into trials using agents that are not renally excreted; (5) patients with microscopic surgical margins can be included; (6) patients should undergo a standard bilateral lymph node dissection prior to enrollment; (7) computed tomographic (CT) imaging should be performed within 4 weeks prior to enrollment. For patients with renal insufficiency who cannot undergo CT imaging with contrast, noncontrast chest CT and magnetic resonance imaging of the abdomen and pelvis with gadolinium should be done; (8) biopsy of indeterminate lesions to evaluate for malignant disease should be done when feasible; (9) a uniform approach to evaluate indeterminate radiographic lesions when biopsy is not feasible should be included in any trial design; (10) a uniform approach to determining the date of recurrence is important in interpreting adjuvant trial results; and (11) new high-grade, upper-tract primary tumors and new MIBC tumors should be considered recurrence events.

Conclusions and Relevance

A uniform approach to eligibility criteria, definitions of no evidence of disease, and definitions of disease recurrence may lead to more consistent interpretations of adjuvant trial results in MIBC.

FDG PET-CT for lymph node staging of bladder cancer: a prospective study of patients with extended pelvic lymphadenectomy

BACKGROUND

The purpose of this study was to evaluate the diagnostic accuracy of [(18)F] fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) for lymph node (LN) staging of bladder cancer patients undergoing radical cystectomy (RC) with extended pelvic lymphadenectomy compared to conventional CT.

METHODS

A total of 61 patients underwent FDG PET-CT before RC and extended pelvic lymphadenectomy. A template for extended pelvic lymphadenectomy to the level of the inferior mesenteric artery was divided into 11 anatomic nodal packets. Definitive pathologic findings of resected LNs were correlated with the results of FDG PET-CT and CT alone in a patient- and nodal packet-based manner.

RESULTS

Among the 61 patients, pathological staging confirmed LN metastasis in 17 patients (27.9 %). In total, 627 LN packets (2580 LNs) were resected and histologically evaluated. The mean number of LNs removed was 42 (median 40; range 22-118). Of the 627 LN packets removed, 27 packets (4.3 %) were positive for LN metastasis based on pathologic analysis. On a patient-based analysis, FDG PET-CT and conventional CT showed a sensitivity of 47.1 and 29.4 %, respectively, specificity of 93.2 and 97.7 %, respectively, positive predictive value (PPV) of 72.7 and 78.2 %, respectively, and negative predictive value (NPV) of 82.0 and 78.2 %, respectively. On a nodal packet-based analysis, sensitivity, specificity, PPV, and NPV were 14.8, 97.8, 23.5, and 96.2 %, respectively, for PET-CT and 11.1, 98.7, 27.3, and 96.1 %, respectively, for conventional CT.

CONCLUSIONS

Combined FDG PET-CT did not improve the diagnostic accuracy of conventional CT for the detection of LN metastasis in bladder cancer patients scheduled for RC.

NLR is predictive of upstaging at the time of radical cystectomy for patients with urothelial carcinoma of the bladder

OBJECTIVE

To evaluate the ability of preoperative neutrophil-lymphocyte ratio (NLR) to predict pathologic upstaging and nonorgan-confined (NOC) (≥pT3) disease.

METHODS AND MATERIALS

After institutional review board approval, the records of consecutive patients undergoing radical cystectomy (RC) for urothelial carcinoma from 2002 to 2012 at the University of Wisconsin Hospital were reviewed. A total of 102 patients with NLR within 100 days of surgery were eligible for analysis. The primary outcome was difference in stage from preoperative assessment to time of RC. Differences in preoperative NLR between groups were evaluated with an unequal variance t test. A univariate analysis assessed whether NLR, preoperative stage, grade, associated lymphovascular invasion, preoperative hydronephrosis, gender, previous pelvic radiotherapy, previous intravesical bladder cancer treatments, or nodal stage were related to upstaging. Multivariate analyses were performed to evaluate the relationship of NLR to upstaging and relative organ-confined (≤pT2) and NOC disease.

RESULTS

Of 390 consecutive patients undergoing RC, 102 patients met study criteria. Overall, 55 (53.9%) patients were upstaged, 25 (25.5%) were unchanged, and 21 (20.6%) were downstaged. Fifty-one patients (50%) were upstaged to more advanced disease (≥pT3). NLR and preoperative hydronephrosis were significantly related to pathologic tumor staging. NLR, preoperative hydronephrosis, and preoperative tumor stage were significantly related to upstaging to NOC disease. Patients who were upstaged to≥pT3 demonstrated statistically significant greater NLRs (4.33±0.87) compared with patients who remained at≤pT2 stage (2.66±0.29) (P<0.001).

CONCLUSIONS

Preoperative NLR is a simple measurement that can be used to identify high-risk patients who may be upstaged at the time of RC and may benefit from neoadjuvant chemotherapy.

CLT1 targets bladder cancer through integrin α5β1 and CLIC3

High-grade non-muscle-invasive bladder cancer is commonly treated with Bacillus Calmette-Guérin, an immunotherapeutic that depends on fibronectin and tumor cell integrin α5β1 for internalization into bladder cancer cells. We previously showed that the anti-angiogenic peptide CLT1 forms cytotoxic complexes with fibronectin that are cooperatively internalized into proliferating endothelium through ligation of integrins and chloride intracellular channel 1. While CLT1 has no effect on mature, differentiated cells, we show here that CLT1 is highly cytotoxic for a panel of bladder tumor cell lines as well as a variety of cell lines derived from kidney, lung, breast, and prostate cancer. Paralleling our previous results, we found CLT1-induced tumor cell death to be increased in the presence of fibronectin, which mediated CLT1 internalization and subsequent autophagic cell death in a mechanism that depends on tumor cell integrin α5β1 and chloride intracellular channel 3 (CLIC3). This mechanistic link was further supported by our results showing upregulation of α5β1 and CLIC3 in CLT1-responsive tumor cell lines and colocalization with CLT1 in tumor tissues. Incubating tumor tissue from patients with bladder cancer with fluorescein-conjugated CLT1 resulted in a strong and specific fluorescence whereas normal bladder tissue remained negative. On the basis of its affinity for bladder tumor tissue and strong antitumor effects, we propose that CLT1 could be useful for targeting bladder cancer.