Objective: Myoma therapy by uterine artery occlusion using laparoscopic ligation (UAOL) has been performed for many years and has proven effective, but limited information is available on its therapeutic mechanism. To examine this issue, we conducted this study to investigate the morphological change and apoptosis occurring in myomal and adjacent myometrial tissues shortly after UAOL.
Study design: In total, 16 myomas and adjacent myometrium were obtained from 7 cases before and at various points after artery ligation. The tissues were stained using hematoxylin and eosin for morphological observation. To investigate the existence of apoptosis, in situ immunostaining of Caspase 3 and TUNEL assay were performed. Cytochrome C released from mitochondria was also detected by immunohistochemistry.
Results: Microscopic observation found that after UAOL, both myometrial and myomal tissues were edematous and apoptotic cells were widespread in both tissues. TUNEL assays showed that before UAOL, numbers of apoptotic cells in myomal and myometrial tissues had no significant differences (P=0.866). After ischemia of (36.69+/-18.53) min, apoptosis was significantly more elevated in myoma than in myometrium ((6.43+/-4.38)/10 HPF vs. (2.74+/-1.95)/10 HPF, P=0.003). Caspase 3 stain shared similar features with the TUNEL assay. In both groups cytochrome C was released from mitochondria after UAOL, and more was detected in the myoma.
Conclusion: UAOL is an alternative method to treat symptomatic uterine myomas. Apoptosis via mitochondrial pathways may lead to reduction of the volume of myoma and myometrium and eventual relief of symptoms.