Platelet inhibition for reactive thrombocytosis in pseudomyxoma

  • Research type

    Research Study

  • Full title

    A prospective observational study to measure platelet inhibition by aspirin administered for reactive thrombocytosis in Pseudomyxoma Peritonei patients

  • IRAS ID

    318927

  • Contact name

    Sophia Stanford

  • Contact email

    sophia.stanford@hhft.nhs.uk

  • Sponsor organisation

    Hampshire Hospitals NHS Foundation Trust

  • Duration of Study in the UK

    2 years, 0 months, 31 days

  • Research summary

    Summary of Research
    Pseudomyoma peritonei is a rare abdominal cancer that arises from the appendix. The current treatment is major surgery and heated chemotherapy which is administered directly into the abdomen. After surgery some patients develop reactive thrombocytosis (high platelet counts) which may cause abnormal blood clots. For this reason patients are given 75mg of aspirin prophylactically to inhibit platelets for a period of approximately 6 weeks. Although these patients are given aspirin we do not know currently how effective the aspirin is in blocking platelets as some patients do not respond to aspirin, a phenomenon known as 'aspirin resistance' or 'aspirin treatment failure'. This study aims to identity patients who are aspirin resistant using VerifyNow, a point of care test that measures how effectively aspirin is blocking platelets.

    Summary of Results
    The study was terminated for the following reasons:
    There were several protocol deviations that affected the aims of the study. These deviations included discontinuation of aspirin prior to 6 weeks as required by standard care. In some patients aspirin was discontinued prior to discharge for clinical reasons which affected the study significantly and we were not able to collect study specific data. The protocol required blood samples to be taken at baseline before administration of aspirin, 4 hours post aspirin, day 1, day 3 and day 5. There were however several missing time points because the patients were discharged or the aspirin was stopped. Of the 30 that were recruited we only have 7 evaluable patients which is not enough to get meaningful results. Furthermore, the VerifyNow machine was unreliable and did not work at some time points and it was not ethical to approach the patient again for additional blood samples. The company was contacted for advice and recalibrated the instrument but it did not make a difference. No patients were affected by the study or clinical decisions outside of the study.

  • REC name

    North of Scotland Research Ethics Committee 2

  • REC reference

    22/NS/0156

  • Date of REC Opinion

    28 Nov 2022

  • REC opinion

    Favourable Opinion