The technology

Immunoscore (HalioDx) is an in vitro diagnostic test designed to predict the risk of relapse in people with localised colon cancer. The technology is designed to assess the microenvironment surrounding tumour cells, providing a measurement of the person's immune response at the tumour site.

The technology uses image analysis and software to measure the density of specific immune cells (CD3+ and CD8+ T lymphocytes) in digital images of tumour samples from resection surgery. Data have shown that assessing immune status with a scoring system that quantifies the density of these specific immune cells in the core and invasive margins of the tumour can indicate tumour recurrence and survival beyond microsatellite-instability staging (see Mlecnik et al. 2016). The software uses computer vision and neural network-based algorithms to distinguish the tumour zone from healthy tissue before measuring the density of CD3+ and CD8+ tumour-infiltrating lymphocytes at both the core and periphery (or invasive margins) of the tumour and automatically assigning an Immunoscore. There are 5 Immunoscore values (IS 0 to 4). A high Immunoscore of 2 to 4 indicates a higher level of immune cell infiltration, suggesting that the person's immune system is actively fighting the cancer and the risk of relapse is low. A low Immunoscore of 0 or 1 indicates a higher risk of relapse. The technology is intended to be used with the tumour, node, metastasis (TNM) cancer staging system to help guide treatment strategies. This could potentially lead to fewer people having more, or less, chemotherapy treatment than is needed.

The Immunoscore test is done at dedicated HalioDx laboratories (France and the US) using tumour samples in the form of a formalin-fixed paraffin-embedded (FFPE) block or microscope slides. HalioDx organises shipment of the unstained tumour sample to the laboratory using a specimen collection kit containing a prepaid courier company airway bill and test request form. In the HalioDx laboratory, the tumour FFPE block or slides are stained for CD3+ and CD8+ T lymphocytes using an Immunoscore CE‑IVD-marked kit and digitally scanned and analysed by the Immunoscore software. Results are reported back to the referring clinician through the HalioDx secure web platform within 10 working days of receiving tumour samples. The company states that the maximum turnaround time of 10 days is guaranteed by standardisation of the process and has been validated by a feasibility study (see Belaloui et al. 2018). The results give the Immunoscore category and risk group. They also give an overview of a clinical management decision tree based on the risk profile. Images are not provided with the test report but the company states that they can be made available on request.


Immunoscore uses a novel approach to predict risk of relapse in people with early‑stage colon cancer by measuring the person's immune response to the tumour instead of tumour cell biology. It is a tissue‑based immune assay, which uses digital pathology alongside deep learning-based algorithms (a type of artificial intelligence) to assess the infiltration of CD3+ and CD8+ T-cells in the tumour core and at the invasive margin. It is the first commercially available tool to do this. It is a non‑invasive test that uses already available resection tumour samples, meaning people will not need to have further procedures.

Current care pathway

The main treatments for localised colon cancer are surgery and chemotherapy. The treatment offered depends on the stage and grade of cancer, as well as the general health and fitness of the person having the treatment. The TNM staging system is the most widely used histological classification system for staging cancer.

Standard care for localised colon cancer is to offer surgery to people who are able to have it, to remove the section of the colon containing the cancer. Some people may be offered chemotherapy before surgery.

Adjuvant chemotherapy is recommended after surgery in people with stage 3 colon cancer to reduce the risk of the cancer returning (relapse). Current standard care for this is capecitabine with oxaliplatin (CAPOX) for 3 months. If this is not suitable, oxaliplatin with 5‑fluorouracil and folinic acid (FOLFOX) for 3 to 6 months or single‑agent fluoropyrimidine (for example, capecitabine) for 6 months may be an option. The type and duration of chemotherapy treatment is based on the stage and characteristics of the cancer, and the person's performance status, comorbidities, age and personal preferences. Adjuvant chemotherapy is not recommended for routine treatment of stage 1 or 2 colon cancer but may be considered in people with stage 2 disease who have a higher risk of relapse.

The following publications have been identified as relevant to this care pathway:

Population, setting and intended user

Immunoscore is intended to be used for risk classification in people with localised colon cancer (stage 1 to 3) in addition to TNM classification.

Colorectal cancer (cancer of the colon or rectum, or bowel cancer) is the fourth most common cancer in the UK, with around 42,300 new cases diagnosed each year (Cancer Research UK, 2017). Risk factors include increasing age, genetics and family history (particularly syndromes such as familial adenomatous polyposis and Lynch syndrome), inflammatory bowel disease, and other dietary and lifestyle factors. Survival rates have improved over time, and almost 60% of people diagnosed with colorectal cancer live for at least 5 years. Survival is linked to disease stage at presentation, with better survival the earlier the disease is detected and treated.

The technology would be used in secondary care by healthcare professionals, such as medical oncologists involved in making decisions about a person's treatment.


Technology costs

The company states that the cost per Immunoscore test is £2,250 (VAT exempt). This includes costs associated with ordering and shipping the sample to HalioDx laboratories, as well as the costs associated with processing the sample, running the assay and reporting the Immunoscore test results.

Costs of standard care

Immunoscore is intended to be used in addition to standard TNM risk classification for the staging of localised colon cancer.

Resource consequences

Immunoscore is not currently used in the NHS but has been used by private hospitals in the UK. Adopting Immunoscore is likely to present an additional cost to standard care. However, using the test to refine cancer staging has the potential to be resource releasing if it can help identify people with low risk of relapse who would benefit from more intense surveillance instead of chemotherapy, which is costly and associated with toxicity. Minimal to no training is needed for healthcare professionals using the test, and no changes to facilities or infrastructure are needed to adopt the technology because the test is done at HalioDx laboratories. The test is also done using available resected tumour samples without the need for additional test-specific procedures.