Iris Metastasis of Non-small-cell Lung Cancer Confirmed via Aqueous Humor Cytology

Purpose: To report an iris metastasis associated with non-small-cell lung cancer (NLC) confirmed via repeat aqueous humor cytology.Case summary: A 53-year-old female presented to our ophthalmology outpatient department with complaints of vision impairment and pain in the left eye 1 month in duration. In ophthalmologic examinations, the best-corrected visual acuities were 20/20 oculus dexter (OD) and 20/32 oculus sinister (OS). The intraocular pressures measured using standard Goldmann applanation tonometery were 12 mmHg OD and 42 mmHg OS. Slit-lamp examination revealed multiple iris nodules in the left eye. Thirteen months prior, the patient had been diagnosed with NLC and was on chemotherapy. Despite the maximal tolerated medical therapy, the intraocular pressure was not controlled. As an iris metastasis was suspected, anterior chamber paracentesis was performed for aqueous humor sampling. Cytological analysis did not reveal malignant cells. One week later, aqueous humor sampling was repeated. Malignant cells were histopathologically confirmed. Given the ocular metastasis, the oncologists changed the chemotherapy regimen.Conclusions: When an NLC patient exhibits iris nodules, repeat aqueous humor cytology can confirm an iris metastasis.