A Case Study of Unusual Etiology of Anterior Uveitis with Ocular Hypertension-Iris Metastasis of Primary Lung Adenocarcinoma

Abstract

This is a case of anterior uveitis in a 50 year-old man caused by lung adenocarcinoma metastasis to the iris. The patient was initially worked up for pneumonia and was discovered to have multiple lung lesions on computed tomography scan. Prior to discharge, the patient began complaining of ocular redness, pain, photophobia and decreased visual acuity. The patient was given an initial diagnosis of anterior uveitis with uveitic glaucoma, which was later confirmed to be secondary to lung adenocarcinoma metastasis to the iris. Metastasis to the iris is a particularly rare cause of anterior uveitis and may inadvertently be left out of a physician's differential diagnosis. This case illustrates a rare, but clinically important cause of anterior uveitis with intraocular hypertension, which should be considered in all cases of ocular redness and pain.

Introduction

Uveitis is inflammation of the middle portion of the eye, consisting of the iris, ciliary body and choroid. The differential diagnosis for uveitis is extensive and diverse. While systemic immune-mediated and infectious causes are responsible for the majority of non-idiopathic uveitis cases, cancer should be considered in all cases of uveitis as a life-threatening cause associated with significant mortality and morbidity. Uveal metastasis is the most common intraocular malignancy but is only estimated to consist of 5%–10% of all intraocular neoplastic cases.¹ The choroid is the most common site for uveal metastasis, whereas involvement of the ciliary body, retina, optic disc, vitreous and iris are rare.²,-⁴ Iris metastasis may appear as a yellow gelatinous mass located within the iris stroma and may cause ocular hypertension, hyphema, and cysts. Two thirds of iris metastases originate from breast or lung cancers but up to one third of patients have no previous history of cancer at the time of ocular diagnosis.⁵ Because iris metastasis is a rare cause of uveitis, it often may not be considered in the differential diagnosis. This is a case of anterior uveitis caused by metastasis of lung adenocarcinoma to the iris. This case illustrates a rare cause of anterior uveitis, which should be considered in future differential diagnoses.

Case Presentation

A 50 year-old Samoan man presented to a local hospital-based outpatient clinic with a chief complaint of shortness of breath and odynophagia. He had recently been an inpatient at the same hospital with similar symptoms and was discharged after 3 days with a diagnosis of pneumonia. Since discharge, he again began experiencing shortness of breath, cough, and odynophagia. For one week he experienced difficulty swallowing solids and eventually liquids due to the severity of pain. He was started on vancomycin, ciprofloxacin and clindamycin (for hospital-acquired pneumonia). The next day the patient was sent to the Medical Intensive Care Unit with a rising fever, hypotension, and hypoxemia. During his admission, he received a computed tomography (CT) scan and a chest X-ray revealing extensive right lower neck supraclavicular and paratracheal necrotic adenopathy, as well as increasing opacity in the right chest with mediastinal involvement. It was at this time that a physical exam revealed mild redness of his left eye without blurry or double vision. Review of past medical history was significant for diabetes mellitus type II, and non-small cell lung cancer with brain metastases. The patient had completed radiation therapy and was scheduled for chemotherapy in the upcoming month.

One week later the patient was being considered for discharge, but began complaining of eye pain and redness of his left eye with decreased visual acuity and photophobia. Ophthalmology consult was requested to evaluate the patient's condition. Examination revealed a normal right eye, but his left eye measured “count fingers only” (CF) visual acuity, a minimally responsive and irregular pupil, and increased intraocular pressure of 44mmHg (normal is <20mmHG). Anterior segment exam of the left eye revealed mild conjunctival injection, moderate corneal edema, heavy cell and flare in the anterior chamber, an irregular pupil with fluffy infiltrative lesions on the pupillary margins, and a moderate cataract. Dilated exam of the retina was difficult due to a very hazy view. The patient was given an initial diagnosis of anterior uveitis with uveitic glaucoma. Topical pressure lowering medications, steroid therapy and pupillary dilating agents were started and the patient was scheduled for re-evaluation the following day.

The next morning the patient was re-evaluated by the ophthalmologist and found to be significantly improved. Visual acuity of the left eye improved to 20/50, intraocular pressure was reduced (estimated by palpation), anterior segment exam revealed better visibility with less reaction, and dilated retina exam was clear. The patient no longer complained of pain and was scheduled for outpatient evaluation by the ophthalmologist. Current topical therapy was continued.

During the outpatient visit the patient's eye condition had further improved, with visual acuity 20/20 bilaterally, intraocular pressure 13mmHg bilaterally and a normal bilateral external eye exam. Anterior chamber exam revealed a normal right eye, and minimal cells in the left eye. It was noted that in the left eye there was posterior synechiae with several cystic, lobular, translucent masses on the anterior iris measuring up to 2 mm in size. The initial impression at that time was of iris mass lesions suspicious for metastasis from lung cancer with associated uveitic glaucoma. The patient was instructed to continue topical pressure lowering medications, steroid therapy and mydriatic agents, as well as continue with the planned chemotherapy.

Over the next 2 months the patient returned to the hospital with recurring bouts of obstructive pneumonia secondary to his lung cancer. He was lost to follow up for his eye examinations. At that point it was determined that he was no longer a good candidate for chemotherapy. The patient was accepting of death and elected to be discharged from the hospital where he returned home and subsequently passed away.

Discussion

This case illustrates a rare but clinically important cause of anterior uveitis with intraocular hypertension. While the presentation of lung cancer in this patient made metastasis a more obvious possible cause of anterior uveitis, it is important to keep neoplastic etiologies in the differential diagnosis of anterior uveitis with ocular hypertension. Anterior uveitis is a process of intraocular inflammation involving the iris, choroid, and ciliary body, and can result from many causes including systemic immune-mediated diseases, infectious agents, and masquerade syndromes (including cancer). While only occurring in a minority of cases, the implications of underlying malignancy require physicians to be aware of syndromes masquerading as uveitis. Masquerade syndromes are noninfectious processes that can cause uveitis and are most commonly caused by malignancy. They most often present bilaterally and usually lack inflammatory features such as keratic precipitates and synechiae.¹ There are several common types of neoplasms that affect the eye such as B cell lymphomas, uveal melanomas, retinoblastomas, xanthogranulomas, and metastatic tumors.

B cell lymphoma is the most common malignancy that causes uveitis.³ B cell lymphoma can be confined to the eye and the central nervous system and present as bilateral, insidious visual decline, usually after the 5th decade of life. Subretinal pigment epithelial lesions and systemic involvement are typical of B cell lymphoma. B cell lymphoma should be suspected when inflammation persists despite steroid therapy or when neurological symptoms are present.

Uveal melanomas can present with episcleritis, anterior and posterior uveitis, endophthalmitis, and panophthalmitis. Uveal melanomas may have features of metastatic melanoma and may be necrotic, diffuse or plaque-like.³

Retinoblastomas present by age 6 and can have a variety of findings. Lesions are most often unilateral and can present as anterior uveitis, vitreitis, or shifting white hypopyon, and often have a lack of calcification.¹

Juvenile xanthogranulomas can appear as yellowish iris nodules, diffuse thickenings, heterochromias, or spontaneous hyphemas. This condition can present with raised, red-yellow skin lesions, 85% of which occur before one year of age.¹

Metastatic tumors are the most common intraocular malignancy in adults.^2–4,6 Tumors are usually bilateral, multifocal and plateau-shaped. They can present either posteriorly as yellow posterior segment lesions with subretinal fluid, or anteriorly as anterior uveitis, iris nodules, and neovascularization of the iris. Metastasis more commonly involves the posterior chamber, with iris involvement being rare.^7,8 Unlike uveal melanomas, which typically only involve the inferior quadrants, metastatic tumors may involve any quadrant of the iris. Metastasis to the iris, as in the presented case, usually presents with blurred vision, ocular pain, redness, visible iris mass, and photophobia. Diagnosis is usually made via ultrasound and CT scan of the mass, and fine needle biopsy for cytologic verification. Lung and breast carcinomas are the most common sites of primary cancers. Systemic review and a thorough history are also important for elucidating this diagnosis.

Conclusion

This case illustrates a rare cause of anterior uveitis which might have been mismanaged were it not for the patient's prominent cancer history. Obtaining a careful history, searching for signs of metastasis, and ruling out systemic and infectious illness allows for the best chance of catching these rare and potentially fatal etiologies of anterior uveitis.

Conflict of Interest

None of the authors identify a conflict of interest.