Focus on haematogenous dissemination of the malignant cystosarcoma phylloides: institutional experience

Cystosarcoma phylloides (CSP) is a fibro-epithelial neoplasm of the breast. Not all CSP cases present as malignant tumors; they are therefore classified as benign, malignant, and borderline subtypes according to the WHO classification. The classification is based on several histopathological features of the neoplasm, such as mitosis rate or invasive growth of the tumor. The progression of this disease is mainly influenced by the classification of their degree. In western countries, this tumor entity usually occurs between 50 and 60 years of age. The major problem in the handling of these patients is the high local recurrence rate, whereas haematogenous metastasis is seldom seen. We therefore report three cases of haematogenous spread in a group of eight patients (two borderline and six malignant cases of CSP).

In this study, we investigated all patients suffering from malignant or borderline CSP, between May 1995 and January 2009, who were under the care of the Department of Gynecology and Obstetrics, University Hospital, Ulm. A written and informed consent was obtained from all patients included in this retrospective study. During this period, eight patients, fulfilling the criteria discussed before, were under the care of the Department of Gynecology and Obstetrics. All therapeutic decisions were taken by the interdisciplinary tumor board of the department (after 1999).

In the retrospective analysis of our study group, we found a high percentage of haematogenous metastasis that was always accompanied with a very poor prognosis in malignant CSP patients. Those patients always died within a short period of time. Two of these patients showed, while they underwent initial surgery, no metastatic suspect lesions and underwent R0 resection; both received a radical mastectomy. One patient already showed lung metastasis while undergoing first line surgery, because she initially declined surgery. We therefore speculate that postoperative adjuvant chemotherapy could lead to a favorable outcome in high risk patients, concerning the development of haematogenous metastasis.