The SIOP Annual Congress brings together paediatric oncology professionals from all over the world dedicated to advancing treatment for children, adolescents, and young adults.

We encourage attendance from all over the world and we are happy to help with your travel planning by providing the following information.

Visa Process

The first step to start the process would be to check whether you need to go through the visa application process or if you can get the Electronic Travel Authorization (eTA). You can check this here.

In case you do need to apply for a visa, SIOP can provide a letter stating your intent to attend the SIOP Annual Congress, which may assist you in obtaining your travel visa. Attendees may request a visa letter using the link during the registration process. Attendees must register and pay in full prior to requesting a visa letter. Visa letters are not available to attendees who are not paid in full or who have cancelled their registration.

The SIOP 2023 Ottawa Annual Congress is a registered event with the Immigration, Refugees and Citizenship Canada (IRCC). See details here.

Events registered with IRCC are issued a unique special event code to help track and monitor visa processing. Applicants should tag their applications with the event’s special event code, which can be found in the letter of invitation provided by the event organizer.

Please note that Visitor Visa (Temporary Resident Visa – TRV) applications are considered on a case-by-case basis based on the information presented by the applicant.

The onus is on the applicant to demonstrate they meet the requirements for a TRV.

While a special event code has been assigned to your event, it does not offer any advantage to the applicant, in terms of a positive visa outcome.

The applicant must meet all the eligibility criteria in order to receive a visa.

In urgent cases, the SIOP Office can also assist with a more tailor-made visa letter as opposed to the standard one and please contact for further assistance.

If you need another copy of your registration confirmation email, please contact our registration team at

If you are unable to receive a visa to leave your country or are unable to enter Canada, contact us regarding a refund.

Please be aware that visa appointments at your local/regional Canadian Embassy or Consulate could take a significant amount of time to secure, so make sure to plan well ahead.

For more information about obtaining a visa, please visit the official website of the Government of Canada here

Visa-exempt (eTA eligible) travellers need an Electronic Travel Authorization (eTA) to board their flight to Canada. However, these travellers do not need an eTA if entering by land or sea – for instance driving from the U.S. or coming by bus, train, or boat, including cruise ship.

For more information about how to apply for the Electronic Travel Authorization (eTA) click here