Developing a Diagnostic Multivariable Prediction Model for Urinary Tract Cancer in Patients Referred with Haematuria: Results from the IDENTIFY Collaborative Study

BACKGROUND

Patient factors associated with urinary tract cancer can be used to risk stratify patients referred with haematuria, prioritising those with a higher risk of cancer for prompt investigation.

OBJECTIVE

To develop a prediction model for urinary tract cancer in patients referred with haematuria.

DESIGN, SETTING, AND PARTICIPANTS

A prospective observational study was conducted in 10 282 patients from 110 hospitals across 26 countries, aged ≥16 yr and referred to secondary care with haematuria. Patients with a known or previous urological malignancy were excluded.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcomes were the presence or absence of urinary tract cancer (bladder cancer, upper tract urothelial cancer [UTUC], and renal cancer). Mixed-effect multivariable logistic regression was performed with site and country as random effects and clinically important patient-level candidate predictors, chosen a priori, as fixed effects. Predictors were selected primarily using clinical reasoning, in addition to backward stepwise selection. Calibration and discrimination were calculated, and bootstrap validation was performed to calculate optimism.

RESULTS AND LIMITATIONS

The unadjusted prevalence was 17.2% (n = 1763) for bladder cancer, 1.20% (n = 123) for UTUC, and 1.00% (n = 103) for renal cancer. The final model included predictors of increased risk (visible haematuria, age, smoking history, male sex, and family history) and reduced risk (previous haematuria investigations, urinary tract infection, dysuria/suprapubic pain, anticoagulation, catheter use, and previous pelvic radiotherapy). The area under the receiver operating characteristic curve of the final model was 0.86 (95% confidence interval 0.85-0.87). The model is limited to patients without previous urological malignancy.

CONCLUSIONS

This cancer prediction model is the first to consider established and novel urinary tract cancer diagnostic markers. It can be used in secondary care for risk stratifying patients and aid the clinician's decision-making process in prioritising patients for investigation.

PATIENT SUMMARY

We have developed a tool that uses a person's characteristics to determine the risk of cancer if that person develops blood in the urine (haematuria). This can be used to help prioritise patients for further investigation.

O6 Reshaping the diagnostic pathways for investigation of haematuria during and after the COVID-19 pandemic: Diagnostic accuracy of strategies for the detection of bladder cancer from the IDENTIFY cohort study

Background

Haematuria often requires investigation with an imaging test and flexible cystoscopy to rule out urinary tract cancers. With a reduction in diagnostic services due to the COVID-19 pandemic there is a risk of compromise in the care of patients referred with haematuria. We aimed to provide a pragmatic strategy that optimises the use of scarce resources by reducing patient visits to hospital and allocating the appropriate diagnostic tests according to risk of bladder cancer.

Methods

The IDENTIFY study was an international, prospective, multicentre cohort study of over 11,000 patients referred to secondary care for investigation of newly suspected urinary tract cancer. Patients underwent cystoscopy, imaging tests, urine cytology and transurethral resection of bladder tumour (TURBT), where indicated. We developed strategies using combinations of imaging and cytology as triage tests to flexible cystoscopy. These strategies aimed to maximise cancer detection within a pragmatic pathway in a resource-limited environment.

Findings

8112 patients (74·4%) received an ultrasound or a CT urogram, with or without cytology. 5737 (70·7%) patients had visible haematuria (VH) and 2375 (29·3%) had non-visible haematuria (NVH). Amongst all patients, 1474 (18·2%) had bladder cancer; 1333 (23·2%) in VH group and 141 (5·94%) in NVH group. Diagnostic test performance was used to determine optimal age cut-offs for each proposed strategy. We recommended proceeding directly to TURBT for patients of any age with positive triage tests for cancer. Patients with negative triage tests under 35-years-old with VH, or under 50-years-old with NVH can safely be discharged without undergoing flexible cystoscopy. The remaining patients may undergo flexible cystoscopy, with a greater priority for older patients (threshold of 60-years-old with VH, or 70-years-old with NVH) to capture high risk bladder cancer.

Interpretation

We suggest diagnostic strategies in patients with haematuria, which focus on detection of bladder cancer, whilst reducing the burden to healthcare services in a resource-limited setting.

Bone marrow mesenchymal stem cells increase motility of prostate cancer cells via production of stromal cell-derived factor-1α

Prostate cancer frequently metastasizes to the bone, and the interaction between cancer cells and bone microenvironment has proven to be crucial in the establishment of new metastases. Bone marrow mesenchymal stem cells (BM-MSCs) secrete various cytokines that can regulate the behaviour of neighbouring cell. However, little is known about the role of BM-MSCs in influencing the migration and the invasion of prostate cancer cells. We hypothesize that the stromal cell-derived factor-1α released by BM-MSCs may play a pivotal role in these processes. To study the interaction between factors secreted by BM-MSCs and prostate cancer cells we established an in vitro model of transwell co-culture of BM-MSCs and prostate cancer cells DU145. Using this model, we have shown that BM-MSCs produce soluble factors which increase the motility of prostate cancer cells DU145. Neutralization of stromal cell-derived factor-1α (SDF1α) via a blocking antibody significantly limits the chemoattractive effect of bone marrow MSCs. Moreover, soluble factors produced by BM-MSCs greatly activate prosurvival kinases, namely AKT and ERK 1/2. We provide further evidence that SDF1α is involved in the interaction between prostate cancer cells and BM-MSCs. Such interaction may play an important role in the migration and the invasion of prostate cancer cells within bone.