Ocular metastasis of renal cell carcinoma is rare, and metastasis to the iris or ciliary body is especially uncommon. Ferry and Font1 studied 227 cases of metastatic tumors of the eye and orbit and reported that 26 (11.5%) of these lesions were iris or ciliary body tumors and that 2 (0.9%) originated in the kidney. We examined a patient with an iris tumor that metastasized from a renal cell carcinoma and observed marked effects of interferon alfa administration.
A 55-year-old man was seen on September 3, 1992, with a 1-week history of decreased vision in his right eye. His history included radical right nephrectomy for renal cell carcinoma in December 1990 and left partial pneumonectomy due to lung metastasis in June 1992.
The corrected visual acuity was 20/20 OU and the intraocular pressure was 11 mm Hg OU. Slitlamp biomicroscopy showed cells in the anterior chamber and a well-circumscribed solid tumor (8 × 4 mm) in the iris of the right eye (Figure 1). The mass was vividly red and contained prominent internal blood vessels. Satisfactory visualization of the entire right fundus was not possible because of insufficient mydriasis, but a retinal detachment was noted in the periphery between the 3- and 7-o'clock positions. B-scan ultrasonography revealed a ciliary body mass at the inferonasal part of the ciliary body. No abnormality was noted in the left eye.
Left, A well-circumscribed solid tumor, which appeared vividly red and contained prominent internal blood vessels, is observed on the iris between the 3- and 7-o'clock positions. Right, The tumor appeared to be totally regressed and white 16 weeks after the beginning of interferon alfa administration.
Systemic examination revealed swelling of the cervical lymph nodes, and results of computed tomographic scans and magnetic resonance images of the head disclosed a cerebral tumor in the right occipital lobe. Biopsy of the cervical lymph nodes established lymph node metastasis of the renal cell carcinoma (Figure 2). Because neurological symptoms such as disturbance of consciousness appeared thereafter, the brain tumor was resected on October 8, and the tumor was confirmed histopathologically to be a metastasis of the renal cell carcinoma.
Light microscopic appearance of lymph node metastasis displaying sheets of polyhedral-shaped cells with clear cytoplasm (hematoxylin-eosin, original magnification ×100).
Systemic interferon alfa was started on October 23 for conservative treatment of the iris tumor. The dose was set initially at 21,000,000 U/wk, but it was reduced to 9,000,000 U/wk in the second week due to bone marrow suppression (decrease in white blood cells and platelets) and to 6,000,000 U/wk in and after the third week. The iris tumor began to regress about 3 weeks after the beginning of interferon alfa administration, and it appeared totally regressed and white after 16 weeks (Figure 1). The retinal detachment disappeared, and the ultrasonographically demonstrated tumor in the ciliary region was not detected. However, the tumor metastasized to the lung, liver, and bones thereafter, and the patient died on June 20, 1993.
Renal cell carcinoma accounts for 80% to 85% of the malignant tumors of the kidney.2 Metastases were reported to be present in 25% to 30% of patients with renal cell carcinoma at the initial examination.2 Metastases of renal cell carcinoma are hematogenous and lymphogenous, and the lungs are the most frequent site of the distant metastases, followed by metastases to bones, liver, and brain.2 Metastases to the eye are rare, and those to the iris have been documented in only a few cases, including those reported by Ferry and Font1 and Wyzinski et al.3 The iris tumor of our patient appeared vividly red through the biomicroscope (Figure 1). This color has been recognized by some clinicians as characteristic of many metastatic ocular tumors from renal cell carcinoma. Our patient was treated conservatively because no reduction of vision or secondary glaucoma due to the tumor was noted, and because the prognosis was poor due to multiple organ metastases.
Renal cell carcinoma resists routine chemotherapy and radiotherapy.2 However, since interferon alfa has recently been reported to have a direct antiproliferative effect on renal tumor cells in vitro,4 and to stimulate host mononuclear cells and enhance the expression of major-histocompatibility-complex molecules,2 it has been introduced as a new treatment for renal cell carcinoma. More recently, the effects of interferon alfa when used in combination with interleukin 2 and fluorouracil, or with 13-cis-retinoic acid, have been evaluated.2 The response rate of patients to interferon alfa alone is considered to be about 20%, and its therapeutic effect is limited when it is used alone. However, as some patients such as ours show marked responses, interferon alfa may be useful in patients with intraocular metastases of renal cell carcinoma.
Corresponding author: Tomohiro Ikeda, MD, Department of Ophthalmology, Osaka City General Hospital, 2-13-22, Miyakojimahondori, Miyakojima-ku, Osaka 534-0021, Japan (e-mail: email@example.com).
Ikeda T, Sato K, Tokuyama T. Interferon alfa Therapy Against Metastatic Iris Tumor of Renal Cell Carcinoma. Arch Ophthalmol. 2000;118(6):846-847. doi: