Advice

Summary

Summary

The Prolaris test is a multi-gene assay designed to predict the aggressiveness (growth and spread) of prostate cancer. Most of the relevant evidence is on clinical validity, and evidence for the prognostic value of Prolaris is based only on the retrospective analyses of archived material. No studies examined the prospective use of Prolaris on patient outcomes. Two studies examined whether Prolaris results affected clinicians' treatment decisions. In 1 study, 65% of clinicians changed their treatment recommendation based on Prolaris results. In the second study results caused a change in treatment in 47.8% of patients. Limited economic evidence was identified. The list price for Prolaris is £1,800, excluding VAT.

Product summary and likely place in therapy

  • Prolaris is an in vitro diagnostic test that measures gene expression levels to generate a Prolaris score, a measure of the aggressiveness (growth and spread) of prostate cancer. The Prolaris score is combined with patient and tumour information to generate either the 10-year prostate cancer-specific mortality risk (from biopsy samples) or the 10-year risk of biochemical recurrence (from prostatectomy specimens), which may indicate the need for further treatment.

  • The Prolaris score would be used in addition to existing risk stratification information and is likely to be used in place of available nomograms, where these are used.

Effectiveness and safety

  • The published evidence summarised in this briefing comes from 9 studies including 4,548 patients. No studies examined the prospective use of Prolaris on clinical outcomes.

  • Two retrospective UK-based studies (n=747 and n=349) demonstrated that the Prolaris score was associated with biochemical recurrence or cancer-related mortality. Another retrospective UK study (n=761) found the Prolaris score predicted the 10-year risk of cancer-related mortality, both independently and in combination with standard clinical variables.

  • One retrospective study (n=582) with 3 cohorts (2 in the US and 1 in Germany) found that the Prolaris score was a statistically significant predictor of biochemical recurrence.

  • Another retrospective study (n=141) based in the US found that the Prolaris score was a statistically significant predictor of biochemical recurrence and mortality.

  • Two studies (n=331 and n=1,206) examined the effect of the Prolaris score on clinicians' treatment decisions. The studies found that clinicians would change their treatment plan based on the Prolaris test results in at least 47% of cases.

  • One study (n=413) validated the Prolaris score against the cancer of the prostate risk assessment post-surgical score that is used to predict biochemical recurrence and cancer-related mortality. The study found that the scores were weakly but significantly correlated (r=0.21, p<0.001).

  • One analytical validation study (n=18 samples) examined the reproducibility and precision of the Prolaris gene signature, the quantity and stability of extracted RNA and the linear and dynamic range of the Prolaris score. The study found that the score is reproducible and robust.

Technical and patient factors

  • The Prolaris test measures the expression profiles of 31 cell cycle progression genes in prostate biopsy samples.

  • The patient's 10-year prostate cancer-specific mortality risk and 10-year biochemical recurrence risk is estimated based on the addition of the Prolaris score to other scores which combine prostate-specific antigen levels, Gleason score and other tumour characteristics.

  • The tissue samples must be prepared by a hospital pathology department using detailed standard operating procedures before being sent to a Myriad Genetics laboratory in Germany for logging and processing. The total turnaround time, from the date the sample is shipped to the laboratory until the report is sent back to the referring clinician (via secure email), is 14 days.

Cost and resource use

  • Each Prolaris test costs £1,800, excluding VAT.

  • Two economic studies showed that the use of Prolaris reduced costs per patient in a hypothetical US-based cohort and was cost effective in a study based in France.