Stage IVB ROS1-rearranged lung adenocarcinoma with bilateral ocular metastases: durable response to entrectinib

What happened, in summary

A 40-year-old man came to the hospital after 12 days of blurred vision and double vision in the right eye. Eye examination found masses in both uveal tracts, with subretinal fluid affecting the right macula and a second lesion near the left ciliary body; B-scan ultrasonography and angiography supported choroidal tumor involvement with secondary retinal detachment and leakage. Full-body imaging then revealed multiple nodules and masses in both lungs, hypermetabolic bronchial lymph nodes, bone lesions, and the known eye masses. Lung biopsy confirmed adenocarcinoma, and the cancer was staged Stage IVB, T4N3M1c1. Because bilateral primary eye melanoma was considered, doctors also biopsied and removed the accessible left-eye mass through a transscleral approach while preserving retinal integrity and visual acuity. Both the lung and eye tumor tissues showed TTF-1 nuclear positivity, supporting metastatic pulmonary adenocarcinoma. Next-generation sequencing of lung tissue found an EZR-ROS1 fusion with mutation frequency 42.99%. He received transpupillary thermotherapy to the right eye to reduce subretinal fluid and protect vision, followed by entrectinib 600 mg daily through a clinical study. Two months after the eye treatment, OCT showed near-complete resolution of the subretinal fluid, and the macular structure remained intact. The left-eye surgical site showed complete resolution of the original lesion. He continued entrectinib for about 3 years, with systemic evaluations every 3 months and eye follow-up every 6-12 months. His disease remained well controlled with partial remission. At recent follow-up, both eyes had best corrected visual acuity of 20/20, and he reported no treatment-related discomfort.