Background: Secondary 'cannonball' metastases to the lung are frequent and usually associated with disseminated malignancy and poor prognosis.
Aim: To report the case of a patient with metastatic pulmonary endometrial stromal sarcoma who had a previous hysterectomy for benign uterine fibroids and no past history of malignancy.
Result: A 70-year-old female presented with cannonball metastases in her lung. Four years previously she had a hysterectomy for 'fibroids'. Review of the original histology revealed endometrial stromal sarcoma, similar to the lung metastasis. She currently has a good prognosis.
Conclusion: A patient with 'cannonball' metastases can have a favourable prognosis. A female patient with a previous hysterectomy for uterine fibroids, should be considered to have metastatic sarcoma until proven otherwise.