Background: Metastastic carcinoma to extraocular muscles is extremely rare, but even more so is the case of a bilateral one. Case report: A 50-year-old woman with a history of mastectomy for a T4N1M0 right breast carcinoma was referred to us with diplopia due to bilateral extraocular muscle metastases, 5 years post mastectomy. Multiple metastases to the whole body were also present. A combination of high-dose irradiation, hormonotherapy and chemotherapy were performed. Results: Despite the multidisciplinary treatment approach, the diplopia persisted. A literature review revealed only 4 cases of bilateral metastases to extraocular muscles. The present case is the second attributed to lobular carcinoma and the only one treated with a high dose of radiotherapy combined with systemic therapy. Conclusion: In a cancer patient, any orbital change must be examined for the possibility of an extraocular metastasis. Conclusions affecting the optimal treatment policy of extraocular muscle metastases are difficult to determine, due to the small number of reported cases.