--- title: Follow-up ctDNA Kit | Sample collection guide description: "How to use the Simsen Follow-up ctDNA Kit for ongoing monitoring: four simple steps to collect and ship blood samples, with IFU downloads." --- [Skip to the main content.](https://simsendiagnostics.com/resources-followup-collection-kit#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=AVxigLI9EOBZVzoDKYtBzXe%2BQ3hVDBQOpNHX0Bv5G%2F9jom3EvRzP4vlCNPRZ5wfiDYiJBmVK5OTe6xGdyosq1s%2B5hyy2cNJPhdJZnEXLXXCMUkFGV9tvGtdX%2F2Rl2X5JV%2Bu%2FtSqoy6YPkKLwuNf4JK4e0eed7HnqQtMvDZe71xWp%2FUWaF9sG08kKUQPj3jVHJ6XiAYBzbSEM&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=AVxigLI9EOBZVzoDKYtBzXe%2BQ3hVDBQOpNHX0Bv5G%2F9jom3EvRzP4vlCNPRZ5wfiDYiJBmVK5OTe6xGdyosq1s%2B5hyy2cNJPhdJZnEXLXXCMUkFGV9tvGtdX%2F2Rl2X5JV%2Bu%2FtSqoy6YPkKLwuNf4JK4e0eed7HnqQtMvDZe71xWp%2FUWaF9sG08kKUQPj3jVHJ6XiAYBzbSEM&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](https://simsendiagnostics.com?hsLang=en) / [Resources](https://simsendiagnostics.com/resources-hub?hsLang=en) / Follow-up kit Instructions for use # Simsen Personal Follow-up ctDNA Collection Kit. **ctDNA monitoring** For patients already set up with a Baseline kit. One venous blood draw, two Streck tubes, for each ctDNA monitoring timepoint. No tissue or control needed. Follow the four steps and your sample arrives ready to run. [Download PDF (IFU)](https://simsendiagnostics.com/hubfs/IFU%20Blood%20Collection%20Kit.pdf?hsLang=en) ON this page [Kit Contents](https://simsendiagnostics.com/resources-followup-collection-kit#kit-contents) [Storage](https://simsendiagnostics.com/resources-followup-collection-kit#storage) [1 • Collect blood](https://simsendiagnostics.com/resources-followup-collection-kit#collect-1) [2 • Rotate gently](https://simsendiagnostics.com/resources-followup-collection-kit#rotate-2) [3 • Prepare for shipment](https://simsendiagnostics.com/resources-followup-collection-kit#prepare-3) [4 • Ship the samples](https://simsendiagnostics.com/resources-followup-collection-kit#ship-4) ## Kit contents Check that everything below is in your box before you begin. If anything is missing, contact us before you start. ![streck-tubes](https://simsendiagnostics.com/hubfs/streck-tubes.svg) ### Streck tubes x2 10 mL, tan cap (ctDNA) ![edta-tube](https://simsendiagnostics.com/hubfs/edta-tube.svg) ### EDTA tube x1 6 mL, purple cap. First-time patients only ![sample-id-stickers](https://simsendiagnostics.com/hubfs/sample-id-stickers.svg) ### Sample ID stickers x3 barcode and ID ![biohazard-bag](https://simsendiagnostics.com/hubfs/biohazard-bag.svg) ### Biohazard bag x1 resealable ![absorbent-pouch](https://simsendiagnostics.com/hubfs/absorbent-pouch.svg) ### Absorbent pouch x1 leak absorption ![gel-pack](https://simsendiagnostics.com/hubfs/gel-pack.svg) ### Gel pack x1 cushioning ![metallic-envelope](https://simsendiagnostics.com/hubfs/metallic-envelope.svg) ### Metallic envelope x1 sealed containment ![requisition-form](https://simsendiagnostics.com/hubfs/requisition-form.svg) ### Requisition form x1 complete and enclose ![original-box](https://simsendiagnostics.com/hubfs/original-box.svg) ### Follow-up Kit box x1 use for return ## Storage Keep the kit and any samples within range. Temperature is the most common cause of an unusable sample. Storage conditions 18 to 30 °C **Unopened kit**Store between 18 and 30 °C. Do not exceed this range. 6 to 37 °C **Drawn blood samples**Keep between 6 and 37 °C. Do not freeze. The whole kit, ships at room temperature using the enclosed return label. ## The four steps Work through them in order. 1 ### Collect the blood samples 1. Use two 10 mL Streck tubes (tan cap) for every patient. 2. Fill each tube to capacity. If the volume is insufficient, draw an additional tube. 3. Allow each tube to fill for 60 to 90 seconds. 4. Use a 21-gauge straight needle for venepuncture. 5. If a vein collapses, attempt a second venepuncture with a fresh tube. Patients already set up need only the two Streck tubes. A first-time patient also draws the 6 mL EDTA tube (purple cap) for the matched normal control. 2 ### Rotate Streck samples gently Immediately after drawing, gently rotate each Streck tube at least ten times to mix the blood with the reagent. **Do not** shake the samples. **Do not** seal the tubes with parafilm. 3 ### Prepare samples for shipment 1 Label each tube with the patient ID and collection date or timepoint. 2 Place the blood tubes inside the absorbent pouch. 3 Insert the absorbent pouch into the biohazard bag. 4 Place the biohazard bag inside the gel pack for cushioning. 5 Put the gel pack and biohazard bag into the metallic envelope. 6 Complete the requisition form and attach a sample ID sticker. 4 ### Ship the prepared samples 1 Place the sealed metallic envelope and the completed requisition form into the Follow-up Kit box. 2 Attach the return label and seal the package. If preferred, place the kit box inside a secondary envelope and apply the label to the outer packaging. ### First-time patient? A patient who has not been set up yet starts with the Baseline Collection Kit, which covers the tumour tissue, the matched normal control and the first ctDNA draw. [Baseline Kit guide →](https://simsendiagnostics.com/baseline-collection-kit?hsLang=en) QUestions before you draw?   ## Talk to the laboratory? 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