Recurrent Uterine Smooth Muscle Tumor of Uncertain Malignant Potential in a Postmenopausal Woman After Total Abdominal Hysterectomy With Bilateral Salpingo-Oophorectomy: A Case Report.

BACKGROUND

Uterine smooth muscle tumors of uncertain malignant potential (STUMPs) are uncommon uterine neoplasms representing 1%-2% of uterine smooth muscle tumors. Recurrence after hysterectomy in postmenopausal patients has rarely been reported. Molecular alterations associated with recurrence remain poorly characterized. Methylthioadenosine phosphorylase (MTAP) deficiency has been described in sarcomas, but its role in STUMP remains poorly characterized.

CASE PRESENTATION: A 61-year-old postmenopausal woman developed multifocal extrauterine recurrence affecting the rectus abdominis, vaginal cuff, peritoneum, small bowel, and abdominal wall 18 months after total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH-BSO) for presumed leiomyomas. The cumulative clinicopathologic findings were considered most consistent with recurrent STUMP, with one lesion exhibiting loss of MTAP expression. Retrospective review of the original hysterectomy specimen revealed previously unrecognized STUMP features, highlighting the diagnostic challenges at initial presentation.

CONCLUSION

This case presents an unusual multifocal recurrence of STUMP following hysterectomy in a postmenopausal patient and reinforces the importance of long-term surveillance, even after definitive surgical management. Focal MTAP loss was identified in one recurrent lesion and should be interpreted cautiously as a descriptive, hypothesis-generating finding.