Abstract
Introduction/Objective
Intravascular leiomyomatosis, also known as intravenous leiomyomatosis, is characterized by presence of smooth muscle within venous spaces in the myometrium, usually in conjunction with a leiomyoma. Although presence of tumor within lymphatics in addition to veins are alluded to in literature, exclusively lymphatic spread with lymph node metastases have not been previously reported.
Methods/Case Report
A 50-year-old woman presented with left flank pain. CT pelvis showed an enlarged uterus with multiple large leiomyomata as well as pelvic lymph node enlargement. Hysterectomy with bilateral salpingo- ophorectomy and pelvic lymph node dissection was performed. Gross examination revealed multifibroid uterus. Separately sent pelvic lymph nodes showed well-circumscribed, whorled lesions resembling leiomyoma. Microscopically, in addition to typical leiomyomata, a 11.5 cm intramural tumor with epithelioid cells, very rare mitoses and no necrosis was identified. Adjacent to this mass, several large endothelial lined spaces (positive for D240 and negative for CD31), consistent with lymphatics, showed intravascular extension of the same epithelioid tumor. All the pelvic lymph nodes were replaced by the tumor. Due to the unusual morphology and pattern of spread, immunohistochemical stains were performed to rule out an endometrial stromal sarcoma and lymphangioleiomyomatosis. The lesion was positive for desmin, caldesmon, and negative for CD10 and HMB45. Ki67 was extremely low (<1%). Based on morphology and immunophenotype, the tumor was consistent with an epithelioid leiomyoma with highly unusual lymphatic spread through myometrial vessels to regional lymph nodes.
Results (if a Case Study enter NA)
NA
Conclusion
Intravascular leiomyomatosis is a rare condition with no reported progression to malignancy. Typically, benign smooth muscle is present in veins within the myometrium of a leiomyomatous uterus with progressive spread to the right heart via the inferior vena cava. We present the first report of a rare case of intravascular leiomyomatosis with spread exclusively via lymphatics to pelvic lymph nodes.