[Clinicopathologic features and prognostic factors of malignant phyllodes tumors].

Abstract

OBJECTIVE:

To study the clinicopathologic features of malignant phyllodes tumors (PT) by histopathologic analyses, immunohistochemical profiling and DNA content assay, and evaluation of the clinical outcome.

METHODS:

Ten patients with malignant PT from 1999 to 2013 who were treated by surgery were enrolled in this study. The morphologic characteristics were studied under light microscope, standard two-step EnVision method of immunohistochemical staining was used to assess the expression of CK5/6, CKpan, 34β E12, desmin, p63, ER-α, PR, Ki-67, CD34, SMA, p53, p16, bcl-2 and CD117 in the tumors. The corresponding paraffin blocks were also used for flow cytometric DNA content assay. These data were correlated with the follow-up results.

RESULTS:

The median age of onset was 46.5 years old. The mean tumor size was 7.4 cm (2.0-25.0 cm). At the end of the follow-up period (22 to 125 months), there were tumor recurrences in 3/8 patients and the median time of recurrence was 24 months. Metastasis occurred in 3/8 patients who all died of the tumors. PT had heterogeneous histology, with stromal overgrowth with leaf-like projections, periductal stromal overgrowth, and most commonly, diffuse stromal overgrowth with sarcomatous differentiation. The mean positive index of Ki-67 was 11.4%. The stromal tumor cells were positive for CD34, SMA, p53, p16, and bcl-2 in 3/10, 9/10, 6/10, 8/10, and 4/10 cases, respectively. CD117,ER-α and PR were negative. Interpretable DNA histograms were obtained in nine cases with triploidy in two cases.

CONCLUSIONS:

The diagnosis of malignant PT should be considered based on the diversity of growth patterns and heterogeneous histology.Ki-67 and CD34 are valuable diagnostic and prognostic factors in patients with malignant PT. Tumors with diffuse stromal overgrowth, heterologous elements, Ki-67 ≥ 20% or aneuploidy are more likely to metastasize.

• Authors: Cui Jia, Fang Mei, Jie Zheng, Jiang-feng You, Jian-ying Liu
• Journal: Zhonghua bing li xue za zhi = Chinese journal of pathology (Zhonghua Bing Li Xue Za Zhi) Vol. 42 Issue 11 Pg. 729-34 (Nov 2013) ISSN: 0529-5807 [Print] China
• PMID: 24447548 (Publication Type: English Abstract, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, CD34
• Ki-67 Antigen

Topics

• Adult
• Aged
• Antigens, CD34 (metabolism)
• Bone Neoplasms (secondary)
• Breast Neoplasms (genetics, metabolism, pathology, surgery, therapy)
• Chemoradiotherapy, Adjuvant
• Diploidy
• Female
• Follow-Up Studies
• Humans
• Immunohistochemistry
• Ki-67 Antigen (metabolism)
• Lung Neoplasms (secondary)
• Mastectomy (methods)
• Middle Aged
• Neoplasm Recurrence, Local
• Phyllodes Tumor (genetics, metabolism, pathology, secondary, surgery, therapy)
• Triploidy