Typical manifestations of orbital metastases include a palpable mass causing displacement or proptosis of the globe, pain, inflammation, bone involvement, chemosis, and eyelid swelling [5].
Metastases to the eye and orbit have been described for a variety of solid tumors, but breast carcinoma accounts for the majority of ocular and orbital metastases [6–9]. In breast cancer - the most frequent cause of cancer-related death in women [10] - orbital metastases have been described in large studies in the range from 28.5-58.8% [1, 11, 12]. Orbital metastases from breast cancer tend to infiltrate the extraocular muscle and surrounding orbital fat, causing motility deficits. The histology features of adenocarcinoma of the breast vary, and the histologic features of orbital metastases may differ from the primary tumor.
Patients who have been diagnosed with orbital metastases usually carry a poor prognosis: the mean survival after diagnosis of such metastases is 31 months (range, 1-116 months) [13]. Even if the orbit is the only clinical suspected site of metastatic involvement, the likelihood of further distant metastases in other organs is high as was shown in our patient following further staging procedures.
Treatment of orbital metastases aims at improving patient's quality of life and restore or preserve visual function. Usually treatment of orbital and ocular metastases is palliative and may include radiotherapy, systemic chemotherapy, hormonal therapy, or surgery in selected patients.
Radiotherapy is the mainstay for orbital and ocular metastases and appears to be safe and effective with objective response rates up to 79% [14]. Radiotherapy improves symptoms in 80% of cases and restores vision in some cases [15]. However, cataract formation and radiation retinopathy are potential side effects of external beam radiotherapy; these potential sequelae must be balanced against the overall prognosis and survival of the individual patient [12, 16]. Systemic chemotherapy is another mainstay in the palliative setting of orbital metastases; in addition the initiation of bisphosphonate treatment is important if osseous metastasis have been diagnosed. Novel targeted systemic treatments are increasingly used in addition to cytostatic chemotherapy. Recently, one case of dramatic local response of a unilateral choroidal metastasis in Her2/neu-positive breast cancer to systemic therapy with trastuzumab and vinorelbine was reported [17].
In general, extensive orbital surgery to remove the metastasis is not recommended as this is not curative and may be associated with significant ocular morbidity [15]. Enucleation or rather radical measures offer no advantages in terms of progression or survival and should only be used in cases of intractable ocular pain or unmanageable local hygiene due to rapid tumor growth [5]. The only appropriate surgical intervention for breast carcinoma metastatic to the orbit is a biopsy to establish the diagnosis [5].
In summary, although rare, breast cancer patients can develop metastases to the orbital and ocular region. Patients with a history of breast cancer presenting with ocular symptoms such as ptosis, proptosis, diplopia, pain, exophthalmus should be evaluated for orbital metastases. Once diagnosis is confirmed treatment for patients with orbital metastases is multidisciplinary.