Breast cysts are the most common benign changes at women aged 35 to 50 years old. Usually there isn’t highest risk for breast cancer in women with cystic changes, but in the rare cases cancer can be found in association with a cyst. We reported two patients aged 33 and 45 years old. Both of them had breast cystic changes. We performed Fine Needle Aspiration (FNA) with cytological examination of the aspirated content, the breast ultrasound examination and mammography for second patient. Cysts were surgically removed and sent to the final histopathological verification. Patient 33 years old was diagnosed medullary breast cancer and undergone axillary dissection and breast sentinel node biopsy (SNB) with histopathological (HP) and immunohistochemical (IHC) findings, after that patient was treated with adjuvant chemotherapy. In patient 44 years old was diagnosed mucinous breast cancer, performed partial breast resection with axillary dissection and applied adjuvant hormonal therapy. Radiotherapy was conducted on both patients and they were followed for 3 years by a regional oncologic dispensary. Although malignant cells wasn’t find by cytological examination we have to be careful because in the wall of the cyst may be malignant cells, so histopathological (HP) and immunohistochemical (IHC) findings are the most relevant diagnostic procedures. Primary treatment of breast cancer is surgery, but important role in management have postoperative radiotherapy, chemotrerapy and hormonal therapy. Survival depends on the size, type of tumor and affected lymph nodes. Prognostic parameters which should be considered are: menopausal status, tumor size, tumor location, lymph node status, tumor type, nuclear grade, histological grade,
hormone receptors and tumor markers.