Phyllodes tumor

Bostwick DG, Hossain D, Qian J, et al. Phyllodes tumor of the prostate long-term followup study of 23 cases. 1 Urol. 2004 172 894. 

Primary liposarcomas (S-100-f) of breast are rare tumors that may arise in a pre-existing phyllodes tumor (CD34-F stroma). 

Non-carcinomatous spindle cell proliferation in a breast core biopsy sample includes fibromatosis, myofibroblastoma, stromal component of phyllodes tumor, or rare primary sarcomas. 

Fibroadenomas and phyllodes tumors comprise the vast majority of fibroepithelial tumors of the breast, though mammary hamartomas and periductal stromal tumor are also considered in this category. 

FIGURE 19.35 Ki-67 expression in benign (A, B), borderline (C, D), and malignant (E, F) phyllodes tumors of the breast. Labeling indexes as demonstrated by Ki-67 expression generally correlate linearly with tumor grade. 

FIGURE 19.36 EGER expression in two malignant phyllodes tumors (A, B). ECFR expression has been shown to be more common in malignant phyllodes tumors and usually corresponds to polysemy 7 rather than ECFR amplification. 

Overall, studies aimed at developing better prognostic markers in phyllodes tumors have suffered from low sample size, a lack of patient follow-up data, and lack of reproducibility. The most significant consistently reported variables in the prediction of phyllodes tumor behavior remain histologic characteristics, in particular the presence of stromal overgrowth and adequate surgical resection margins. 773-279... 

Fibroadenoma versus Phyllodes Tumor IHC and Molecular Approach... 

The main diagnostic dilemma involving fibroepithelial lesions of the breast is probably differentiating cellular fibroadenomas from benign phyllodes tumors, since... 

FIGURE 19.37 Proliferative activity in fibroadenomas versus benign phyllodes tumors. The fibroadenoma depicted in (A) and (B) shows no Ki-67 positive stromal cells, whereas that depicted in (C) and (D) shows focal ( 1 %) Ki-67 stromal cell immunoreactivity. Note the numerous positive ductal epithelial cells. Similarly, a benign phyllodes tumor may show minimal or no proliferative activity with Ki-67 as shown in (E-H). 

Periductal stromal tumor was initially described by Burga and Tavassoli as a distinct entity from phyllodes tumors that was histologically identical but lacked the intracanalicular or leaflike pattern.Like phyllodes tumors, however, the stromal cells express CDS 4, and thus some have proposed that they are best regarded as a phyllodes tumor variant that lacks the classic leaflike architecture rather than a distinct entity. 

Phyllodes tumor stroma is CD34 positive, a finding that is useful in the workup of spindle cell lesion in a core biopsy. 

Ki-67 may supplement grading of phyllodes tumor in addition to morphology and counting of mitotic figures. 

Ki-67 proliferation index does not reliably distinguish between fibroadenoma and phyllodes tumor. 

Molecular analyses in distinguishing fibroadenomas from phyllodes tumors have also been inconclusive. 

Periductal stromal tumor is likely a variant of phyllodes tumor it also has a CD34-positive stroma. 

Dunne B, Lee AH, Finder SE, et al. An immunohistochemi-cal study of metaplastic spindle cell carcinoma, phyllodes tumor and fibromatosis of the breast. Hum Pathol. 2003 34 1009-1015. 

Noguchi S, Motomura K, Inaji H, et al. Clonal analysis of fibroadenoma and phyllodes tumor of the breast. Cancer Res. 1993 53 4071-4074. 

Aranda FI, Laforga JB, Lopez JI. Phyllodes tumor of the breast. An immunohistochemical study of 28 cases with special attention to the role of myofibroblasts. Pathol Res Pract. 1994 190 474-481. 

Sapino A, Bosco M, Cassoni P, et al. Estrogen receptor-beta is expressed in stromal cells of fibroadenoma and phyllodes tumors of the breast. Mod Pathol. 2006 19 599-606. 

Shpitz B, Bomstein Y, Sternberg A, et al. Immunoreactivity of p53, Ki-67, and c-erbB-2 in phyllodes tumors of the breast in correlation with clinical and morphologic features. J Surg Oncol. 2002 79 86-92. 

Suo Z, Nesland JM. Phyllodes tumor of the breast EGER family expression and relation to clinicopathological features. Ultra-struct Pathol. 2000 24 371-381. 

Tse GM, Putti TG, Kung FY, et al. Increased p53 protein expression in malignant mammary phyllodes tumors. Mod Pathol. 2002 15 734-740. 

Esposito NN, Mohan D, Brufsky A, et al. Phyllodes tumor A clinicopathologic and immunohistochemical study of 30 cases. Arch Pathol Lab Med. 2006 130 1516-1521. 

Kersting C, Kuijper A, Schmidt H, et al. Amplifications of the epidermal growth factor receptor gene (egfr) are common in phyllodes tumors of the breast and are associated with tumor progression. Lab Invest. 2006 86 54-61. 

Inoshita S. Phyllodes tumor (cystosarcoma phyllodes) of the breast. A clinicopathologic study of 45 cases. Acta Pathol Jpn. 1988 38 21-33. 

Khan SA, Badve S. Phyllodes tumors of the breast. Curr Treat Options Oncol. 2001 2 139-147. 

Kuijper A, de Vos RA, Lagendijk JH, et al. Progressive deregulation of the cell cycle with higher tumor grade in the stroma of breast phyllodes tumors. Am J Clin Pathol. 2005 123 690-698. 

Asoglu O, Ugurlu MM, Blanchard K, et al. Risk factors for recurrence and death after primary surgical treatment of malignant phyllodes tumors. Ann Surg Oncol. 2004 11 1011-1017. 

Chen WH, Cheng SP, Tzen CY, et al. Surgical treatment of phyllodes tumors of the breast Retrospective review of 172 cases. J Surg Oncol. 2005 91 185-194. 

Cheng SP, Chang YC, Liu TP, et al. Phyllodes tumor of the breast The challenge persists. World Surg. 2006 30 1414-1421. 

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