Tubular/cribriform breast cancer

Hi, just wondering if anyone else has been diagnosed with tubular/ cribriform breast cancer as it is a rare type. All the information I have read about this type states it is generally a small tumour only 10mm or less in size and slow growing. I was told mine was 10mm in size but after surgery they discovered it was actually 45mm. This is confusing me, how is mine so big and how long must I have had it. Any one with any similar stories or advice?