The service moved to a purpose-designed space at Plymouth Marjon University in March as part of a collaboration between the university and the trust.
The trust said the additional space would allow the team to develop new programmes focused on helping patients manage pain and improve their overall wellbeing.
Johnson and her mother took part in the new unit’s official opening ceremony.
She said she hoped other patients would benefit in the same way she had.
She added: “As long as I am cancer free until 2029, they can take the pump out.
“Usually people have it to get them through the last part of their life, but, for me, it’s been totally different.”
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