Leiomyosarcoma vs pelvic masses and getting a diagnosis

Hello, I am here trying to find as much information as possible about pelvic masses... particularly lieomyosarcomas. My oldest daughter just turned 24. She's always had rough menstrual cycles, recently she started having pelvic pain, bladder pressure, bowel issues and rectum pains....then she had groin pain followed by soft swelling in her leg, close to her knee. Her primary MD suspected the leg swelling might be a lymphnode, as it was tender and red. He started her on antibiotics and scheduled an ultrasound. The antibiotics took care of the swelling. The US showed her uterus as unremarkable with large complex pelvic mass... 11 cm... differentials were endiometrioma, cystadenoma or cystsacarcinoma.... please forgive any misspelling here.... the report recommendated a CT for better view because visualization was suboptimal. Her blood work for cancer markers was good. She received the results of her CT yesterday.... all other organs are clear, lungs, liver, etc...bowels within normal limits, etc.... no lymph node involvement....but now this radiologists is saying " worrisome for liemyosarcoma". She has an appointment with her gyno monday. I'm just looking for info on this rare cancer. I'm a little confused about her uterus being unremarkable... I was under the impression the uterus was enlarged with this cancer. I'm also unfamiliar with the term " worrisome ".... I've always seen "suspicious" used in these situations, what does worrisome mean exactly? Any info would be deeply appreciated. Thank you