Leiomyoma is a benign tumor of soft tissue and occured in nearly every organ and every location in the soft tissue. Under the microscope, they are nearly identical in every site. The diagnosis leiomyoma based on absence of nuclear atypia, necrosis and no or minimal mitotic activity . Leiomyomas of the genitourinary tract may originate from any structure containing smooth muscle. Smooth muscle tumors of non-visceral soft tissue lesions can be divided into two categories: superficial subcutaneous lesions and deeper soft tissue ones . At first of one are subdivided into: arrector pili in origin, blood vessels wall in origin (angioleiomyomas), and those arising in relation to smooth muscle found in the skin of the scrotum, glans penis or vulva-genital leiomyomas .
Glans penis leiomyomas are uncommon as primary nonepithelial tumors urogenital tract. Only seven cases has been described until today [3,4,5].
We also describe another rare case of a man with a leiomyoma of the glans penis.
A 79 year-old Caucasian male T. H., was referred to our Medical Center complaining of a painless penis mass that had enlarged over a six year period. He didn't any constitutional symptoms and denied any history of trauma. The patient was not previously treated.
A physical examination only showed a giant 40 mm diameter, irregular, cauliflower, hard fixed solid mass of tumor in the glans penis, covered with skin. This lesion had been taken out of superior surface of corona glandis, solitary and well circumscribed. A total resection of tumor was performed (21.09.2004) i. e. a complete exicision of free margins should be histologicaly established to prevent recurrence. The patient's post surgery recovery continued without any problems. As of now our patient is still well and without any symptoms.
The excised material was fixed in formalin and embedded in paraffin. The sections were stained by hematoksylin and eosin (H. E.). Additionally, the immunoperoxidase method was used for analysis the markers of cytoskeleton of cells. The antibody to actin (SMA) DAKO production was performed.
Pathological examination (nr 29675/7384/4) showed - macro: tumorous excision lesion covered skin with diameter 40 mm, a total resection was performed - a complete excis with free margins. Microscopic examination revealed a leiomyoma glans penis, confirmed immunohistochemical - positive for alpha-SMA (alpha-smooth muscle actin) - Ass prof. A. Nasierowska-Guttmejer, pathomorphologist.
Smooth muscle tumors of the penis - the leiomyoma of that localization - are extremely rare. Those tumors were generally painless, solitary and well circumscribed and none have recurred or metastasized. However this tumor should be included in the differential diagnosis of the neoplasm of the glans penis. The differential diagnosis for this case, includes piloleiomyomas are frequently encapsulated and, as the name suggests, are highly vascularized. Piloleiomyomas are usually poorly delineated and are more dermal than subcutaneous. Neither piloleiomyomas nor angioleiomyomas should show significant cytological atypia but both lesions are generally painful . This lesion doubtlessly must undergo to the extent surgical excision. On the other hand not only clinically but pathologicaly should be confirmed the clinical suspicion of a benign versus malignant gland penis lesion.
Immunohistochemical analysis using the streptavidin-biotin peroxidase technique and immunoreactivity for cytokeratin, S100 protein the proliferative marker MIB1 must be performed in order that confirming the pathologic diagnosis. Others markers, such as alpha-smooth muscle actin (alpha-SMA) and desmin, considered specific for smooth muscle cell, have been shown to be expressed in a variety of myofibroblastic processes .
The histopathological evaluation found the fusocelluar pattern of tumor focally with bizzare cells. The immunohistochemical expression of actin was observed in tumor cells. The microscopic analysis identified the most common mesenchymal tumor of penis.
Recapitulated complete excision followed by histological and immunohistochemical examination is the reliable means of distinguishing leiomyoma from other neoplasms of the glans penis. The treatment that includes complete excision free margins should be histologically estabished to prevent recurrence.
Sławomir A. Dutkiewicz
ul. Lachmana 2 m. 56
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