This is a randomized placebo controlled double blind window of opportunity trial. A maximum
of 120 patients will be enrolled. Up to 60 patients with invasive breast cancer will be
enrolled into cohort 1, and up to 60 patients with DCIS will be enrolled into cohort 2.
Patients in each cohort will be randomized 1:1 to either CBD or placebo control using
permuted block randomization with random block sizes of 2 or 4. The time window between CBD
or placebo initiation and surgery will be between 5 days and 56 days.