Clinical and pathological characteristics of benign metastasizing leiomyoma / 中国癌症杂志

ABSTRACT

Background and purpose: About 20 cases of BML have been reported in the literature,they occurred in females with history of uterus leiomyoma.BML appears as a histopathologic benign smooth muscle tumor located far from the uterus,often in the lungs.Firstly,it should be confirmed as originating from smooth muscle by immunohistochemistry,Secondly,its primary tumor should be confirmed as benign,with mucoid degenenation,it also should be distinguished from myxoid leiomyosacroma.Methods:We report a case of benign metastasizing leiomyoma,study its clinical,histopathologic and immunohistologic features,discuss the diagnosis and differential diagnosis and give a review of the related references.Results:The case occurred in a forty-two year old female who was found to have bilateral lung nodules after hysterectomy of her uterus leiomyoma six years ago.An open lung biopsy revealed the nodules to consist of proliferating smooth muscle cells with a histopathologic feature similar to her uterus leimyoma,consistent with the diagnosis of BML.Positive staining of estrogen and progesterone receptors was detected in both the uterus leiomyoma and the metastasizing lesions.No significant increase or enlargement of the lung nodules were found seven months after the operation with no therapy except taking Chinese traditional medicine.Conclusions:BML is a rare entity usually occurring in females with history of uterus leiomyoma.It appears as a histopathologic benign smooth muscle tumors distant from the uterus.It is hormone dependent and progresses slowly.