BACKGROUND: Leiomyosarcoma of the vulva is a rare mesenchymal tumor. Biologic features of a low grade tumor were investigated by an immunohistochemical workup. CASE: A 38-year-old woman presented with a slowly growing vulvar mass. Surgical treatment was performed, and a low grade leiomyosarcoma of the vulva was diagnosed. Immunohistochemical reactions were performed with monoclonal antibodies against desmin, vimentin, smooth muscle actin, cytokeratin, S-100 protein, estrogen, progesterone and androgen receptor, p53 protein, Ki-67 antigen, leukocyte common antigen and polyclonal antibodies to factor VIII-related antigen. Expression of estrogen, progesterone and androgen receptor was present in addition to a moderate number of Ki-67-positive cells and absence of p53 protein overexpression and lymphatic cell infiltration besides adequate microvessel density for smooth muscle tumors. Since the immunohistochemical markers indicated a less aggressive tumor, any further adjuvant therapy was rejected. The patient was without recurrence 24 months later. CONCLUSION: The immunohistologic profile proved the low histologic grade of vulvar leiomyosarcoma. The findings helped to estimate prognosis and plan therapy.
BACKGROUND:Leiomyosarcoma of the vulva is a rare mesenchymal tumor. Biologic features of a low grade tumor were investigated by an immunohistochemical workup. CASE: A 38-year-old woman presented with a slowly growing vulvar mass. Surgical treatment was performed, and a low grade leiomyosarcoma of the vulva was diagnosed. Immunohistochemical reactions were performed with monoclonal antibodies against desmin, vimentin, smooth muscle actin, cytokeratin, S-100 protein, estrogen, progesterone and androgen receptor, p53 protein, Ki-67 antigen, leukocyte common antigen and polyclonal antibodies to factor VIII-related antigen. Expression of estrogen, progesterone and androgen receptor was present in addition to a moderate number of Ki-67-positive cells and absence of p53 protein overexpression and lymphatic cell infiltration besides adequate microvessel density for smooth muscle tumors. Since the immunohistochemical markers indicated a less aggressive tumor, any further adjuvant therapy was rejected. The patient was without recurrence 24 months later. CONCLUSION: The immunohistologic profile proved the low histologic grade of vulvar leiomyosarcoma. The findings helped to estimate prognosis and plan therapy.