Tested positive for TNBC, but no Tumor, just calcification

During a mammogram screening they noticed a "cluster of calcifications". This tested positive for cancer. MRI showed no tumor, and did not see any in my lymph nodes, they described it to me as a tree branch, sprinkled with classifications spanning an area of 13 cm .

I received two opinions from Breast Surgeons.

First, Do a Mastectomy and test the whole area to see what percentage is cancerous. Based on the results, decide if chemo is necessary.

Second opinion, Do a Surgical Biopsy to confirm the Triple negative results. The lab that processed the HER2 test, recommended another sample. After the Biopsy proceed with the appropriate Chemo.

I've read the benefits of doing Chemo first, but if I don't need it obvious why would I want to put myself thru it. My head is spinning. Because basically they don't know because they don't see a tumor.

I can't believe my case is the first of a kind and I'm wondering if anybody has gone thru anything similar.

Any advice would be greatly appreciated.