BERKELEY, CA (UroToday.com) - A small proportion (2-5%) of patients with cancer will develop metastases to the ocular or orbital region. Prostate cancer is the third most common primary site for these metastases, behind only breast and lung cancer.[1] In up to 25% of patients with ocular or orbital metastases, it is the presenting sign of malignancy.[1, 2] The clinical presentation depends on the structures affected, but may include pain, diplopia, decreased visual acuity, or proptosis.
If an ophthalmologic assessment confirms an ocular or orbital neoplasm, a rational, multidisciplinary approach to determine the primary source of the metastasis should be undertaken. This assessment would include a thorough history and physical examination. In males, a testicular and prostate exam should be performed. If a systematic work up, which included appropriate blood work and diagnostic imaging, failed to identify the primary source, a fine needle aspiration or excisional biopsy could be considered.[1, 3]
The goal of treatment is dependent on the patient’s burden of disease and performance status, and may range from providing local control to preserve vision and cosmesis, to palliative measures to provide comfort.[1, 4, 5] A recent review of the management of choroidal metastases highlights the efficacy of systemic therapies in providing local control.[6] Although patients with urological metastases were not included in this review, anti-androgen therapy in patients with prostate cancer, and biologic agents in patients with renal cell carcinoma, would likely have similar results as ocular and orbital structures are outside of the blood brain barrier. The patient with an orbital mass in our case report had a local response to anti-androgen therapy for over 2 years.
In situations where systemic therapies are not effective, or contraindicated, a variety of local options exist. The most extreme, enucleation, has no impact on survival, and should be reserved for uncontrolled tumor growth or discomfort.[1] Palliative external beam radiotherapy, however, is non-invasive and generally well tolerated. A prospective trial of 50 patients with choroidal metastases, treated with 40Gy in 20 treatments, identified a complete or partial regression of the tumor in over 80% of patients, with a similar percentage experiencing an improvement or stabilization of their visual symptoms.[7] The most common toxicities were skin erythema and conjunctivitis, occurring in 50% of patients.
It should be noted that this trial was open from 1994-1998. With more modern radiotherapy techniques, current treatment outcomes may be superior to what was previously reported.
Despite these management options, eye and orbital metastases typically occur in the setting of advanced systemic disease, resulting in a median survival of 6 to 9 months.[5] For this reason, if a patient’s presenting sign of malignancy is a metastasis to the eye or orbital region, a logical and careful approach to diagnosis and management -- in order to limit undue burden and morbidity -- is of utmost importance.
References:
- Ahmad SM, Esmaeli B. Metastatic tumors of the orbit and ocular adnexa. Curr Opin Ophthalmol 2007;18:405-13.
- Hesselink JR, Davis KR, Weber AL, et al., Radiological evaluation of orbital metastases, with emphasis on computed tomography. Neuroradiol 1980;137:363-6.
- Shields JA, Shields CL, Brotman HK, et al., Cancer metastatic to the orbit: The 2000 Robert M. Curts Lecture. Ophthal Plas Recons Surg 2001;17:346-54
- Baltogiannis D, Kalogeropoulos C, Ioachim E, et al., Orbital metastasis from prostatic carcinoma. Urol Int 2003;70:219-22.
- Char DH, Miller T, Kroll S. Orbital metastases: diagnosis and course. Br J Ophthal 1997;81:386-90.
- Chen CJ, McCoy AN, Brahmer J, et al., Emerging treatments for choroidal metastases. Surv Ophtalmol 2011;56:511-521
- Wiegel T, Bottke D, Kreusel KM, et al., External beam radiotherapy of choroidal metastases – final results of a prospective study of the German Cancer Society (ARO 95-08). Radiother Oncol 2002;64:13-8
Written by:
Shilo Lefresne, MDa and Alysa Fairchild MD, FRCPCbas part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.
aDepartment of Radiation Oncology, BC Cancer Agency, Vancouver, BC Canada
bDepartment of Radiation Oncology, Cross Cancer Institute, Edmonton, AB Canada
