SHERLOCK Study

SHERLOCK stands for Study of High-Precision Evaluation of Molecular ResiduaL Disease through a PlatfOrm for Cancer TracKing and Interception.

The goal of the SHERLOCK study is to improve cancer outcomes by detecting molecular residual disease (MRD) as early as possible and supporting research that aims to prevent cancer from returning.

MRD means there may be a very small amount of cancer still in the body after treatment. It can be too small to see on CT or MRI scans or find on a physical exam. In some people, MRD may later grow into a cancer recurrence, while in others it may never cause problems. SHERLOCK studies MRD so we can better understand who is at risk and how to prevent recurrence. 

A liquid biopsy is a blood test that looks for traces of cancer in the blood stream. One common way to detect these traces of cancer is to look for fragments of DNA. When these fragments come from cancer cells, they are called circulating tumour DNA (ctDNA). SHERLOCK uses ctDNA testing among other liquid biopsy tests to look for signs of MRD.

You may be able to join SHERLOCK if you are 18 years or older, have been diagnosed with cancer, and are receiving (or have recently completed) treatment. Eligibility depends on your cancer type, treatment plan, and what samples are available. Your care team and the study team will review this with you.

If you choose to join, a member of the study team will review the study with you and ask you to sign a consent form. Blood samples are then collected at planned time points (often coordinated with routine visits), up to a total of 6 times over approximately 12 months. The study team may also use leftover tumour tissue from your surgery/biopsy if it is available, and collect relevant information from your medical records and follow you for up to five years, or until relapse or progression of cancer.

Taking part in SHERLOCK is your choice and you can change your mind at any time without affecting your medical care.

There are no costs to take part in this study, and you will not have to make any extra trips to the hospital. Participants will not be compensated if they choose to join SHERLOCK.

Results will be shared with your treating doctor and placed in your electronic medical records. Other tests done on your blood or tumour samples may be for research only and won't be placed in your medical record.

MRD-positive means the test found a cancer DNA signal in your blood. Your doctor may recommend closer follow-up or additional tests and may discuss whether you could be eligible for a separate MRD-guided “interception” clinical trial to escalate or give additional treatment, if one is available.

MRD-negative means the test did not find a cancer DNA signal at that time. MRD tests are not perfect, so there is a risk of incorrect results. Your MRD result should not replace your usual follow-up care or guideline-recommended surveillance. Your doctor may discuss whether you could be eligible for a separate clinical trial to de-escalate or give less treatment.

SHERLOCK does not include cancer treatment, and there are no treatment studies available for all participants. If your MRD test is positive or negative, it may help determine whether you are eligible for a separate clinical trial to escalate or de-escalate treatment.​​