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.