CLINICAL PRACTICE ARTICLE Thromboembolic events during neoadjuvant chemotherapy in muscle invasive bladder cancer – any correlation to the central venous access? A clinical practice article [version 1; peer review: awaiting peer review] Victoria Eriksson 1 , Elisabeth Eriksson 2 , Amir Sherif 1 1 Department of Surgical and Perioperative Sciences, Urology and Andrology., Umeå University, Umeå, Sweden 2 Department of Radiation Sciences, Diagnostic Radiology, Umeå University, Umeå, Sweden First published: 13 Jan 2022, 11:40 https://doi.org/10.12688/f1000research.75922.1 Latest published: 13 Jan 2022, 11:40 https://doi.org/10.12688/f1000research.75922.1 v1 Abstract Patients with muscle invasive bladder cancer have a generally known 5-year overall survival of approximately 58% with neoadjuvant chemotherapy (NAC). During the last decades, addition of Cisplatinum-based NAC in fit patients prior to radical cystectomy (RC), has significantly improved OS, compared to RC only. However, some published studies following NAC addition, describe an intermediate risk increase of thromboembolic events (TEEs). Placement of central venous access (CVA) before NAC has also been suggested as being a potential risk factor for thrombosis. We present a combination of images and cases from the Northern Swedish health region where three patients developed venous TEE after CVA placement for NAC- administration and found that the time until curable RC was prolonged circa one month each, with an addition of one RC cancelled. These are serious events and to our knowledge, there are no current guidelines on prevention of TEE before RC. The aim with this report was to provide examples of these events and conclude that further prospective trials are warranted on prevention and future guidelines regarding venous anticoagulant treatment for TEE that occur pre-RC in NAC-patients. Keywords Cystectomy, Thromboembolism, Urinary Bladder Neoplasm, Neoadjuvant Therapy, Central Venous Access Open Peer Review Reviewer Status AWAITING PEER REVIEW Any reports and responses or comments on the article can be found at the end of the article. Page 1 of 6 F1000Research 2022, 11:40 Last updated: 13 JAN 2022