NWBO doesn't keep the tumor. It's stored wherever the patient and their surgeon decides to store it. If tumors were stored at NWBO there would be a flat fee to send it to Advent to produce the vaccine.
From Advents payment sheet (CLN-FRM-18, feel free to contact the author Kelley Bolsom)
5.2. Courier Shipping Fees - Transport of frozen tumour tissue to Advent Bioservices to begin the tumour lysate production: Cost varies depending on where the frozen tumour tissue is stored. This fee is payable prior to the first administration of the vaccine.
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