Low-grade endometrial stromal sarcoma recurring with multiple bone and lung metastases: report of a case

BACKGROUND: Approximately 50% of patients with low-grade endometrial stromal sarcoma (ESS) develop recurrent disease, mainly in lung or pelvis. Bone metastasis of low-grade ESS is an extremely rare phenomenon. CASE: A 63-year-old Japanese female developed multiple bone and lung metastases 18 years after initial treatment for low-grade ESS. Bone scintigram showed a high uptake area at thoracic spine (Th6, Th8-9 and Th12), right 9th rib, iliac bone, and sacrum. Radiation therapy with Liniac of 4500cGy to the Th6 vertebra and Liniac of 4200cGy to sacrum was performed for the palliation of the pain. Radiotherapy was effective for the pain relief, although the size of recurrent tumor was unchanged. CONCLUSION: This is the first detailed reported case of multiple bone recurrence in a patient with low-grade ESS. The long-term follow-up after treatment is recommended.