Malignant Cystosarcoma Phyllodes Of Prostate

Abstract

A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45‐year‐old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984.

Molecular Genetic Evidence for Different Clonal Origins of Epithelial and Stromal Components of Phyllodes Tumor of the Prostate

“…Phyllodes tumor is a rare neoplasm of the prostate which may undergo sarcomatous transformation, is prone to early recurrences, infiltrative growth, and has potential for extraprostatic spread. [3][4][5][6][7] Benign clinical courses have been cited, but the follow-up time has been limited. 33 In regards to the stroma, Gaudin et al 34 proposed the clinicopathologic categories of prostatic stromal proliferation of uncertain malignant potential and prostatic stromal sarcoma to differentiate these entities from other mesenchymal lesions of the prostate, using immunohistochemical staining data in conjunction with morphological criteria.…”

“…[1][2][3][4] The malignant potential of this tumor is unclear and has resulted in confusion in terms of prognosis and treatment. Unquestionably, the potential for sarcomatous transformation, recurrence, and infiltrative growth exists, but the frequency of these changes and their prognostic significance is unclear.…”

“…Unquestionably, the potential for sarcomatous transformation, recurrence, and infiltrative growth exists, but the frequency of these changes and their prognostic significance is unclear. [3][4][5][6][7] Little is known about the genetic abnormalities in this tumor. Oncogene activation and tumor suppressor gene inactivation are important mechanisms in the genesis, propagation, and spread of most cancers, but the role of these processes in phyllodes tumor has not been previously explored.…”

Nonepithelial tumor-like lesions of the prostate: a never-ending diagnostic problem

“…The immunohistochemical profile resembles that of postoperative spindle cell nodules; however, the staining intensity of the different markers (smooth muscle actin, vimentin, cytokeratin) is generally much weaker. A recent immunohistochemical study revealed strong positivity for anaplastic lymphoma kinase in inflammatory myofibroblastic tumors (inflammatory pseudotumors) [7,47]. Ultrastructural studies failed to reveal epithelial differentiation, but showed myofibroblastic differentiation.…”

“…The stromal cells are positive for vimentin and occasionally also for desmin. The MIB-1 proliferation index is in the range of 10-20% and the mitotic rate increased [47,48].…”