The abstract submission for ESTRO 2021 will open early January 2021. The submission deadline is 8 March 2021 (23.59 HRS CET). Abstracts must be submitted online on the ESTRO website at www.estro.org.

We highly recommend completing your submission early, otherwise authors may experience technical delays due to server overload.

For questions regarding the online submission process, please e-mail abstracts@estro.org.


With the submission of an abstract for ESTRO 2021, the submitting (presenting) author:

  • Accepts responsibility for the accuracy of the abstract and confirms that all authors are aware of the content before submission
  • Accepts to be the contact person for all correspondence related to the abstract and to inform the co-authors about its status
  • Accepts to declare any financial interest in products or processes described in the abstract. This includes stock ownership, membership on any advisory boards, commercially-sponsored research or any other substantial relationships
  • Certifies that the information reported is for exclusive presentation in the session to which the abstract will be assigned if accepted, and that the information will not be presented as such at any commercially-sponsored satellite symposia during the conference.
  • Abstracts are embargoed until 1 month prior to the congress, at which point the abstract book is published online and abstracts are included in the searchable programme. Should you wish for an abstract to be embargoed until the congress, please email abstracts@estro.org by 16 May 2021.

Further notes:

  • Please log in to the abstract submission site with the presenting author login details.
  • Abstracts must be submitted and presented at the conference in English. The Scientific Programme Committee reserves the right to reject an abstract written in poor English.
  • Abstracts will be anonymised before review to ensure fairness and eliminate possible bias. It is therefore strictly forbidden to include the authors’ names or institutions in the body of the abstracts.



  • Track: choose a track keeping in mind that:
  • Abstracts submitted under the Clinical track are reviewed by clinicians and considered for the Clinical track of ESTRO 2021 only.
  • Abstracts submitted under the Physics track are reviewed by physicists and considered for the Physics track of ESTRO 2021 only.
  • Abstracts submitted under the Radiobiology track are reviewed by radiobiologists and considered for the radiobiology track of ESTRO 2021 only.
  • Abstracts submitted under the RTT track are reviewed by Radiation TherapisTs (RTTs) and considered for the RTT track of ESTRO 2021 only.

It is extremely important that you submit your abstract under the correct track. Submitting under the wrong track will result in your abstract being sent to the wrong experts for review and being scored low as a consequence.

Further advice for submitters:

  • Delineation abstracts: if the focus of the abstract is on imaging techniques, then the abstract should be submitted under the physics topics; if the focus of the abstract is on correctness of TV, OAR, then the abstract should be submitted under the clinical topics or under the RTT topics.
  • Clinical outcome: If there is no clinical outcome (at least toxicity reporting) the abstract should be submitted under the physics topics (or brachytherapy topics).
  • Topic category: choose the topic category that refers to the main subject of the abstract. The Scientific Programme Committee reserves the right to re-categorise the abstract.
  • Keywords: authors are required to select a keyword from a pre-defined menu. The list of keywords corresponding to each topic category can be a useful guide to determine the most appropriate topic category under which to submit the abstract. When submitting your abstract only one keyword can be selected from the pre-defined list.
  • Presentation preference: authors should indicate the presentation preference (oral or poster) Please note that the final decision on the presentation format rests with the Scientific Programme Committee.
  • Title: abstract titles should be brief and reflect the content of the abstract. The title (maximum 100 characters) is important since it focuses attention (it is the “showcase” for the presentation). Do not use capital letters in the title except for words that are always capitalised and do not use non-standard abbreviations.
  • Body of the abstract: abstracts should be structured in such a way as to include (1) Purpose/Objective; (2) Material/Methods; (3) Results; (4) Conclusion.
  • The online abstract submission procedure: the online abstract submission system will not accept abstracts that exceed 3,000 characters (body of the abstract, including spaces).
  • The use of standard abbreviations is desirable. A special or unusual abbreviation must be placed (in round brackets) after the first appearance of the word for which it stands.
  • Table and image: with their submission, authors may include maximum 2 uploads (tables or images) in JPG or PNG formats. These uploads are not included in the number of allotted characters. The maximum pixel size of an image is 600(w) x 800 (h).
  • Data table: authors may include one data table using the insert table icon (we advise not to copy-paste a table into the body of the abstract). The characters in a data table are included in the overall number of characters allowed.
  • Equations: can be inserted in the text as images.

Editing of abstracts: Abstracts can be edited until the submission deadline of 8 March. Any changes to abstracts (including authors and affiliations) are not accepted after this date.



Abstracts submitted for presentation will be reviewed by an international panel of experts in the field of the subject.

Abstract review criteria are based on clarity, supporting data, scientific rigour, potential significance, interest in the topic chosen and innovation or usefulness.

Work in progress: abstracts on research obviously not yet performed and results not yet obtained are be prohibited.

Encore abstracts: papers already presented in another meeting will not be considered, unless the previous audience is distinct from the ESTRO 2021 congress audience (e.g. national meetings).

Papers already accepted for publication will not be considered.

Similar abstracts: if very similar abstracts are submitted by the same authors, the Scientific Programme Committee reserves the right to select only one of the abstracts and reject any others.

Abstracts will be selected for one of the following presentation formats:

  1. Oral presentation: abstracts selected for oral presentation are presented at one of the proffered paper sessions scheduled within the programme.
  2. Poster: abstracts selected as posters will be presented in one of the following 3 presentation formats:
  • Poster Highlights
    Posters (in digital version) with a 4-minute pre-recorded presentation are to be uploaded to the poster gallery. The poster is presented/discussed verbally during a scheduled online Poster Highlights session. These sessions will be moderated. The authors of the selected posters will connect via the presenter portal at the scheduled time. The recorded presentation will play and be followed by 4 minutes of live Q&A. The full session will be recorded and be made accessible shortly after to all delegates via the online platform.
  • Poster Discussion
    Posters (in digital version) with a 3-minute pre-recorded presentation are to be uploaded to the poster gallery. These posters, with their recorded presentation, will be accessible to all delegates from the very start of the congress via the online platform.
  • Poster
    Posters (in digital version) are to be uploaded to the poster gallery. These posters will be accessible to all delegates via the online platform.

Withdrawal of an abstract: abstracts submitted for ESTRO 2021 can be withdrawn until 31 March 2021 (to withdraw your abstract you should send an email to abstracts@estro.org). After this date, withdrawal of abstracts is no longer possible. Abstracts selected for oral/poster presentation should be presented at the meeting. In case the first (presenting) author cannot attend the conference, they should assign a replacement and inform the ESTRO office of the replacement as soon as possible.

Notification of outcome of abstract submission will be sent early May 2021.

A notification email is sent to the email address of the author whose credentials were used to submit the abstract.

Presenting author registration: Presenting authors should register for the congress by 14 June 2021.



  • The work and/or update must be novel, ground-breaking, of high significance, evidence-based and with scientific merit.
  • The work and/or update must be original and not previously published or presented at any other scientific meeting.
  • The abstract must present timely findings which were not available at the time of the deadline (8 March 2021). The late-breaking abstract deadline is not intended to be a second deadline for abstract submissions
  • A limited number of late-breaking abstracts will be accepted.
  • Submissions will be accepted for oral presentation only.

The submission period for late-breaking abstracts runs from 19 April to 5 May 2021.