Phyllodes tumors and fibroadenoma common beginning and different ending

Phyllodes tumors and fibroadenomas are the most common benign breast tumors. They arise from intralobular fibrous tissue as a unique lesion and after a period of time they differentiate in two direction: to fibroadenoma and to phyllodes tumors. Fibroadenomas grow up to 2-3 cm and then stop growing but phyllodes tumors grow continually and sometimes are to 40 cm big. Both these lesions have two components, epithelial and stromal. Clinically fibroadenomas are well circumscibed, hard, oval, movable lesions. They can be solitary, multiple, unilateral and bilateral. They are hormone dependent changes, because they change their own consistency during menstrual cycle and gravidity. The most commonly used histological classification is in two types: pericanalicular and intracanalicular type. Phyllodes tumors make about 1% of all breast tumors. This tumor has many synonyms. It starts as fibroadenoma in intralobular stromal component. It has continuous growth and biologically it can be benign, borderline and malignant. The first description is from Miller (1838). The main goal is to find the divergence point when the developing is direct to fibroadenoma or phyllodes tumor. The second goal is to investigate the fate of epithelial and stromal component in these two lesions. Retrospective analysis is made of all fibroadenomas and phyllodes tumors in Pathology Department of Medical Center "Bezanijska kosa" in the period from 1998 to 2006. In this period, 2919 women were operated for breast changes. 343 fibroadenoma (24, 4%), were diagnosed, benign phyllodes tumor in 95 women (6.7%) and malignant phyllodes in 4 cases or 0.2%. All slides from these patients were analysed for many different histological parameters and immunohistological investigation for steroid receptors was also used, c-erbB2 (Her2/Neu), PCNA (proliferative cellular nuclear antigen) and Ki-67, androgen receptor and p53. All data were statistically investigated (Odds ratio, confidence interval, Fisher exact test, Wilcoxon sum test and Kendall test). It was concluded that fibroadenomas and phyllodes tumors arise from intralobular fibrous tissue, both changes have very close histology in the beginning and divergent growth starts later. Differences are present in stromal component. Phyllodes tumor has two component stroma. Stromal cells in phyllodes tumors are more PCNA positive than in fibroadenomas, also Ki-67 and androgen receptors are more positive in phyllodes tumors. Histologically phyllodes tumors have perforated capsule with finger like projections. These data determine surgical procedure, wide excision in phyllodes and simple excision in fibroadenomas.