Case Presentation: A 59 year-old man with a 30 pack-year smoking history was sent to ED from retina clinic for further workup of recurrent left eye uveitis refractory to steroids. He had a 2 month history of persistent ​left eye central vision loss and floaters, without right eye issues or systemic symptoms. He had negative workup for uveitis, negative blood and vitreal cultures, and unsuccessful trials of intravitreal injections of voriconazole, vancomycin, and ceftrazidine. He also had financial restraints prohibiting further outpatient workup. Visual acuity was severely reduced in the left eye (only able to count fingers), with a nonreactive pupil and limitation in all visual fields. Slit lamp exam showed a hazy vitreous and partial retinal detachment in the left eye. Ultrasound of the left eye showed exudative material under a retinal detachment. Labs were unremarkable, with negative infectious screens. Chest xray showed a 4.1 cm lingular lung mass. This mass prompted workup with MRI brain, revealing bilateral hemorrhagic foci in the cerebral hemispheres, cerebellum, and periventricular areas and left ocular enhancement. Pan scans found cervical, supraclavicular, mediastinal, and hilar lymphadenopathy, a lingular 4.1×3.2×3.3 cm solid mass, subpleural nodule, pericardial nodule, multiple pulmonary nodules, rib lesions, and adrenal nodules. Lung biopsy found tumor cells with intracellular mucin lining the alveolar spaces, leading to diagnosis of metastatic invasive mucinous adenocarcinoma of the lung. The tumor was positive for Protein Death Ligand 1 (50%), with an ERBB2 (Her2-enu) Exon 20 insertion and tumor protein 53 mutation. Plans were made to establish with primary care, medical and radiation oncology, ophthalmology, and pulmonology. He underwent 4 cycles of pembrolizumab plus pemetrexed-carboplatin, then transitioned to Pembrolizumab with plan for maintenance therapy for 2 years.

Discussion: Lung cancer is the most common cause of death in patients with cancer. Most patients are advanced stage at diagnosis, with a poor 5-year survival rate of 12% for overall and of less than 5% for distant metastatic disease. Metastases often involve nearby lymph nodes, bones, liver, brain, adrenal glands, or other parts of lung. This patient is unique in that ocular symptoms were his single presenting symptom (despite late-stage disease), under the facade of uveitis. Masquerade syndromes—where intraocular cells and their paraneoplastic consequences mimic ocular inflammatory conditions—are uncommon (in patients referred for uveitis, only 2.5% had neoplastic masquerades). Thus, we hope this case will escalate awareness and prompt further workup where indicated, especially for patients who are being triaged or hospitalized and who have minimal preventative and screening care.

Conclusions: In the case of this patient, who had no primary care doctor (thereby, no smoking counseling or CT lung cancer screenings) and had no systemic symptoms, expedited workup discovered stage IV lung adenocarcinoma, which was deceiving for refractory uveitis. Choroidal metastasis from primary lung cancer has an incidence between 2-6.7%, yet rarely are visual issues the only presenting symptom prior to diagnosis. Given the overall high mortality and late-stage diagnosis of lung cancer, we hope this case will galvanize the urgent need for screening in high risk patients, encourage energetic counseling and treatment of tobacco use, and increase awareness and thereby diagnosis of choroidal metastasis and masquerade syndromes.

IMAGE 1: CXR and MRI Brain/Orbits

IMAGE 2: Pathology tumor cells