Presumptive iris metastasis with anterior segment complications as the initial presentation of lung adenocarcinoma: A case report

Iris metastasis is a rare ocular problem that accounts for a small proportion of all uveal metastasis. However, it may be the initial presentation in patients with primary systemic malignancy. A 70-year-old gentleman presented with 1-week history of blurred vision and 1-month history of redness in the left eye, alongside a 3-month history of nonproductive cough. Slit-lamp biomicroscopic examination revealed a yellow, well-defined, irregular iris lesion measuring 2.6 × 2.6 × 1.0 mm (height × width × thickness) at 7 o’clock near the pupillary margin with overlying vascularization. Chest X-ray and contrast-enhanced computed tomography (CT) of the thorax, abdomen, and pelvis demonstrated a left middle-to-lower zone opacity. CT-guided bronchoscopy confirmed primary lung adenocarcinoma, and magnetic resonance imaging and positron emission tomography imaging revealed widespread metastases to mediastinal lymph nodes and the brain. The patient was commenced on empirical Gefitinib 250 mg once daily for 2 weeks while awaiting molecular testing and subsequently started on immunotherapy, with Pembrolizumab 100 mg, a PD-1 inhibitor, every 3 weeks, planned for a total of six to eight cycles. This resulted in regression of the iris lesion. After three cycles of immunotherapy (16 weeks of initiation), the repeat CT showed partial reduction of the primary lung lesion but progression of mediastinal lymph nodes and bone lesions. The patient was subsequently counseled for second-line doublet chemotherapy. Ophthalmic examinations 4 months post commencement of 3 cycles of immunotherapy revealed the vascularised iris lesions had decreased in size, measuring 2.5 × 1 × 1 mm (height × width × thickness), appearing as a trilobular mass from 6 to 9 o’clock with endothelial touch. The lesion has been followed for 7 months at the time of writing.

Conclusion:

This case illustrates a rapidly progressing iris metastasis secondary to primary lung adenocarcinoma with systemic metastases. It underscores the importance of early ophthalmic assessment for prompt diagnosis and highlights the challenges of systemic therapy planning for iris metastasis. Early recognition and multidisciplinary coordination are essential for achieving optimal outcomes.