Sixteen year-old with leiomyosarcoma in a prior benign myomectomy site

Uterine leiomyosarcoma in a prior myomectomy site is a rare phenomenon. We report an unusual case of a leiomyosarcoma arising six months post myomectomy in a 16-year old female. Radiographic images (A) starting with the CT of mass on day 0 followed by the CT abdomen/pelvis of second pelvic mass leiomyosarcoma on day 185, the MRI prior to staging surgery on day 317, and finishing up with the MRI of the recurrence of malignancy. Timeline of patient events (B). Our patient initially underwent a diagnostic laparoscopy with pelvic mass biopsies showing leiomyoma which was followed by an abdominal myomectomy. She re-presented to the hospital on Day 190 and urgently underwent an exploratory laparotomy for resection of a pelvic mass which revealed a leiomyosarcoma. The patient subsequently received neoadjuvant chemotherapy (NACT) with ifosamide and doxorubicin and pelvic radiation. On day 316 she underwent surgical staging including hysterectomy and bilateral salpingo-oophorectomy which showed no residual disease. Patient received adjuvant chemotherapy with ifosamide and doxorubicin. On Day 490 patient diagnosed with recurrence of disease and on day 500 underwent exploratory laparotomy with resection of three recurrent abdominal tumors, greater omentectomy, small bowel resection, and heated intraperitoneal chemotherapy (HIPEC) with cisplatin and doxorubicin. For microscopic recurrent and persistent disease the patient will receive gemcitabine and docetaxel. Histological images (C) starting of the pelvic mass biopsy on day 0 followed by the myomectomy on day 8, the primary tumor resection on day 190, the staging surgery showing no residual leiomyosarcoma on day 316, and end with the recurrent abdominal tumor debulking surgery on day 500. [Display omitted] •Malignant transformation of a leiomyoma to a leiomyosarcoma is a rare phenomenon.•Leiomyosarcomas can be extremely aggressive when they present in an adolescence.•Multidisciplinary team needed to treat an adolescent with a leiomyosarcoma.