--- title: Simsen Diagnostics | ctDNA analysis, in your lab or ours description: Detect circulating tumour DNA at the lowest levels with SiMSen-Seq. Run it in your own lab or send samples to ours, for trials, research and clinics. image: https://simsendiagnostics.com/hubfs/simsen-og-why-simsen.png --- [Skip to the main content.](https://simsendiagnostics.com#main-content) [![Simsen logotype](https://simsendiagnostics.com/hs-fs/hubfs/SD_logo%20medium-2.png?width=588&height=164&name=SD_logo%20medium-2.png "Simsen logotype")](https://simsendiagnostics.com?hsLang=en) [![Simsen logotype](https://simsendiagnostics.com/hs-fs/hubfs/SD_logo%20medium-2.png?width=588&height=164&name=SD_logo%20medium-2.png "Simsen logotype")](https://simsendiagnostics.com?hsLang=en) - [PLATFORM](https://simsendiagnostics.com/platform) - [Why Simsen](https://simsendiagnostics.com/why-simsen) - [Our technology](https://simsendiagnostics.com/platform-our-technology) - [Methodology](https://simsendiagnostics.com/platform-methodology) - [Find your approach](https://simsendiagnostics.com/find-your-approach) - [Delivered your way](https://simsendiagnostics.com/both-delivery-models) - [Solutions](https://simsendiagnostics.com/solutions-overview) - [EVIDENCE](https://simsendiagnostics.com/evidence-hub) - [Publications](https://simsendiagnostics.com/evidence-publications) - [Paediatric solid tumours](https://simsendiagnostics.com/evidence-paediatric-solid-tumours) - [CNS tumours & CSF ctDNA](https://simsendiagnostics.com/evidence-cns-csf-ctdna) - [White papers](https://simsendiagnostics.com/evidence-white-paper-ctdna-trials) - [COMPANY](https://simsendiagnostics.com/company-about) - [About us](https://simsendiagnostics.com/company-about) - [Team](https://simsendiagnostics.com/company-team) - [Contact us](https://simsendiagnostics.com/company-contact) - [News](https://simsendiagnostics.com/news) - [RESOURCES](https://simsendiagnostics.com/resources-hub) - [Sample collection guides](https://simsendiagnostics.com/resources-sample-collection-guides) - [Baseline kit guide](https://simsendiagnostics.com/baseline-collection-kit) - [Follow-up kit guide](https://simsendiagnostics.com/resources-followup-collection-kit) Search [![Request a conversation](https://hubspot-no-cache-eu1-prod.s3.amazonaws.com/cta/default/25734893/interactive-412216133822.png)](https://simsendiagnostics.com/hs/cta/wi/redirect?encryptedPayload=AVxigLLBqG3hTGcu%2B8qiXBG3BV785SN%2BYJB8oohovpQ7oFflEPyG98UkAN8fJGWoeS25roofVVKhi8VRwiP3erONAaVKQ7v7xSXbOL8YBUCxbu7gPy02AuWWnJKxsI%2F7%2BaWdB3Qsk5ySCQ%2BA7A%2F9Bd3uRXiy1AlJQ%2Fh0z%2F65s%2FS3XhQUAQIjqTUq%2B2fcnqA7WOvuQ%2FgKm6W5&webInteractiveContentId=412216133822&portalId=25734893&hsLang=en) Toggle Menu Search Toggle Menu [![Request a conversation](https://hubspot-no-cache-eu1-prod.s3.amazonaws.com/cta/default/25734893/interactive-412216133822.png)](https://simsendiagnostics.com/hs/cta/wi/redirect?encryptedPayload=AVxigLLBqG3hTGcu%2B8qiXBG3BV785SN%2BYJB8oohovpQ7oFflEPyG98UkAN8fJGWoeS25roofVVKhi8VRwiP3erONAaVKQ7v7xSXbOL8YBUCxbu7gPy02AuWWnJKxsI%2F7%2BaWdB3Qsk5ySCQ%2BA7A%2F9Bd3uRXiy1AlJQ%2Fh0z%2F65s%2FS3XhQUAQIjqTUq%2B2fcnqA7WOvuQ%2FgKm6W5&webInteractiveContentId=412216133822&portalId=25734893&hsLang=en) - [PLATFORM](https://simsendiagnostics.com/platform) - [Why Simsen](https://simsendiagnostics.com/why-simsen) - [Our technology](https://simsendiagnostics.com/platform-our-technology) - [Methodology](https://simsendiagnostics.com/platform-methodology) - [Find your approach](https://simsendiagnostics.com/find-your-approach) - [Delivered your way](https://simsendiagnostics.com/both-delivery-models) - [Solutions](https://simsendiagnostics.com/solutions-overview) - [EVIDENCE](https://simsendiagnostics.com/evidence-hub) - [Publications](https://simsendiagnostics.com/evidence-publications) - [Paediatric solid tumours](https://simsendiagnostics.com/evidence-paediatric-solid-tumours) - [CNS tumours & CSF ctDNA](https://simsendiagnostics.com/evidence-cns-csf-ctdna) - [White papers](https://simsendiagnostics.com/evidence-white-paper-ctdna-trials) - [COMPANY](https://simsendiagnostics.com/company-about) - [About us](https://simsendiagnostics.com/company-about) - [Team](https://simsendiagnostics.com/company-team) - [Contact us](https://simsendiagnostics.com/company-contact) - [News](https://simsendiagnostics.com/news) - [RESOURCES](https://simsendiagnostics.com/resources-hub) - [Sample collection guides](https://simsendiagnostics.com/resources-sample-collection-guides) - [Baseline kit guide](https://simsendiagnostics.com/baseline-collection-kit) - [Follow-up kit guide](https://simsendiagnostics.com/resources-followup-collection-kit) [For clinical trials Pharma and CROs Validate MRD endpoints, cut trial-arm cost, build EU regulatory readiness. Design a trial assay →](https://simsendiagnostics.com/solutions-trials?hsLang=en) [For research and labs Translational oncology See signal in paediatric and early-stage samples your current platform misses. Send samples or run SiMSen-Seq in-house. See the signal →](https://simsendiagnostics.com/solutions-research?hsLang=en) [For clinics Premium oncology monitoring Detect minimal residual disease ahead of imaging. Logistics across the EU, UK and EEA. Detect relapse earlier →](https://simsendiagnostics.com/solutions-clinic?hsLang=en) Home Tumour-informed ctDNA # Detect what your current platform *misses*. Ultra-sensitive ctDNA monitoring for your clinical trial, your laboratory, your patients. Delivered as a service from our EU lab, or run on your own instruments. [Find your starting point →](https://simsendiagnostics.com/solutions-overview?hsLang=en) [Speak to our scientific team →](https://simsendiagnostics.com/start-a-conversation?hsLang=en) *✓* Parts-per-million sensitivity · Open pipeline, raw data access · EU-based ![Scientist working with pipettes in the Simsen lab](https://simsendiagnostics.com/hs-fs/hubfs/simsen-lab-02-blue-overlay.png?width=1000&height=896&name=simsen-lab-02-blue-overlay.png) Where to start ## Three audiences. Three places to begin. Whoever you are, start with the outcome you need. The science is one click deeper, for when you want it. ![icon-clinical-trials](https://simsendiagnostics.com/hubfs/icon-clinical-trials.svg) ### For clinical trials **Validate MRD endpoints. Move faster.** Design ctDNA endpoints into your European oncology trial, with raw data access and co-publication built in. [Learn more →](https://simsendiagnostics.com/solutions-trials?hsLang=en) ![icon-research-labs](https://simsendiagnostics.com/hubfs/icon-research-labs.svg) ### For research & labs **See signals others miss.** Send samples, or bring SiMSen-Seq in-house on your own instruments. Low-AF detection in paediatric and early-stage samples. [Learn more →](https://simsendiagnostics.com/solutions-research?hsLang=en) ![icon-clinics](https://simsendiagnostics.com/hubfs/icon-clinics.svg) ### For clinics **Catch relapse before imaging does.** Personalised ctDNA monitoring for your oncology patients, with European logistics and time-zone-aligned support. [Learn more →](https://simsendiagnostics.com/solutions-clinic?hsLang=en) Why Simsen ## Ultra-sensitive ctDNA, delivered your way. Five reasons researchers, pharma teams and clinics across Europe choose to work with us. 01 ### Sensitivity You detect signal at parts-per-million, in samples your current platform calls negative. 02 ### Flexibility You choose: send samples to our lab, or run SiMSen-Seq on your own instruments. 03 ### Clinical insight You see actionable variants and tumour evolution, not just a binary positive or negative. 04 ### Transparency You get full raw data access and an open pipeline. Your bioinformatics team can verify, reanalyse or extend our results with their own tools. 05 ### Partnership You work with a specialist team: co-publication, protocol design and interpretation help. Trusted by leading European clinics, hospitals and biotechs ![vg-university-hospital logo](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/vg-university-hospital.png) ![vhio](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/vhio.png) ![onecarbon](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/onecarbon.png) ![epistamaibio](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/epistamaibio.png) ![docrates](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/docrates.png) ![neogap](https://simsendiagnostics.com/hubfs/Customer%20logo%20tp%20png%20files/neogap.png) Evidence ## What ultra-sensitivity looks like for the people doing the work. 0.001 % VAF Panel-level MRD sensitivity in your own samples; per-variant ~0.01%. [Rostamzadeh et al., 2026 →](https://simsendiagnostics.com/hubfs/Posters/poster_ctdna_symposium_aarhus_2026.pdf?hsLang=en) 9 months Earlier than imaging picked up relapse, in paediatric neuroblastoma monitoring. [Ek et al., 2024 →](https://doi.org/10.1158/2767-9764.CRC-24-0338) 68 % Of surveillance scans could have been avoided, in ctDNA-monitored metastatic breast cancer. [MOUHANNA ET AL., 2025 →](https://doi.org/10.1002/ijc.35292) Methodology ## Three ways to monitor ctDNA. They are not interchangeable. Tumour-informed monitoring splits broadly into three approaches: tracking single nucleotide variants, tracking structural variants, or using fixed tumour-naive panels. Each has consequences for your samples. Most platforms hide this choice. We think it deserves daylight. Simsen approach ### SNV-based Personalised and ultra-sensitive, surfacing clinically actionable variants alongside tumour markers. **Best when:** small biopsies, low tumour burden, you want resistance signal. ### SV-based Personalised, sensitive in tumour types with high structural-variant burden, but no resistance information. **Best when:** SV-rich tumours, resistance tracking not required. ### Tumour-naive Fixed panel, no biopsy needed, lower sensitivity at very low allele frequencies. **Best when:** no tissue available, sensitivity is secondary. [Read the full methodology framework →](https://simsendiagnostics.com/platform-methodology?hsLang=en) Talk to us ### Speak to our scientific team A real human, in CET/CEST time zone, who has run samples like yours. [inbox@simsendiagnostics.com](mailto:inbox@simsendiagnostics.com) [Request a conversation →](https://simsendiagnostics.com/start-a-conversation?hsLang=en)   ![full_lockup_white_CMYK kopia](https://simsendiagnostics.com/hs-fs/hubfs/full_lockup_white_CMYK%20kopia.png?width=166&height=45&name=full_lockup_white_CMYK%20kopia.png) **Visiting and postal address:** Pepparedsleden 1 431 53 Mölndal, Sweden **Shipping address:** c/o AstraZeneca R&D Mölndal Pepparedsleden 3 431 53 Mölndal, Sweden PLATFORM PLATFORM - [Platform overview](https://simsendiagnostics.com/platform) - [Why Simsen](https://simsendiagnostics.com/why-simsen) - [Our technology](https://simsendiagnostics.com/platform-our-technology) - [Delivered your way](https://simsendiagnostics.com/both-delivery-models) SOLUTIONS SOLUTIONS - [For clinical trials](https://simsendiagnostics.com/solutions-trials) - [For research and labs](https://simsendiagnostics.com/solutions-research) - [For clinics](https://simsendiagnostics.com/solutions-clinic) - [Solutions overview](https://simsendiagnostics.com/solutions-overview) COMPANY COMPANY - [About](https://simsendiagnostics.com/company-about) - [News](https://simsendiagnostics.com/news) - [Team](https://simsendiagnostics.com/company-team) - [Contact](https://simsendiagnostics.com/company-contact) - [Privacy policy](https://simsendiagnostics.com/legal-privacy-policy) - [Cookie Policy](https://simsendiagnostics.com/legal-cookie-policy) - [Terms of use](https://simsendiagnostics.com/legal-terms-of-use) © 2026 Simsen Diagnostics AB, All rights reserved. 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