Title : The "uninvited guest" on the iris a case of intraocular metastasis during chemotherapy in a 3 year old child with neuroblastoma
Abstract:
Objective: This study aims to report a rare case of sudden iris metastasis in an 3-year-and-8-month-old child with neuroblastoma during the post-primary tumor resection and chemotherapy period. Through clinicopathological comparative analysis, it explores the clinical characteristics, diagnosis and treatment strategies of intraocular metastasis during chemotherapy, as well as the importance of early intervention, so as to provide new clinical evidence for the monitoring of ocular complications in children with neuroblastoma.
Methods: A male child (3 years and 8 months old) with retroperitoneal neuroblastoma, confirmed by surgery and pathology, was enrolled and received chemotherapy after surgery. On the 14th day of chemotherapy, he was admitted to the ophthalmology department due to abnormal white reflex in the left eye noticed by his parents, for screening of ocular metastasis. Clinical examinations showed: a grayish-white cystic round elevated lesion on the surface of the left iris, accompanied by vascularization, without inflammatory reaction or significant visual impairment (A). Ultrasound Biomicroscopy (UBM) indicated an abnormal solid elevation on the surface of the left iris (E). Intraoperative evaluation: tumor resection was performed under general anesthesia, and intraoperative fluorescein angiography confirmed vascular perfusion of the lesion (B). The resected iris tumor tissue was subjected to histopathological and immunohistochemical analysis, and its pathological characteristics were compared with those of the primary retroperitoneal tumor to confirm homology (C). Follow-up also revealed that brain MRI showed uneven local signals on T1-weighted images (white arrow), indicating central nervous system involvement (D).
Results: Clinical Characteristics and Diagnosis-Treatment Process: Iris metastasis occurred after primary tumor resection and in the early stage of chemotherapy (the 14th day), which was different from the common onset in infants under 1 year old reported in the literature. The histological and immunophenotypic features of the iris lesion were completely consistent with those of the primary retroperitoneal neuroblastoma, confirming hematogenous metastasis origin.
Literature Comparison and Rarity: Almost all previously reported cases of iris neuroblastoma occurred in infants under 1 year old, and most of them were diagnosed with primary tumors at the initial visit. This case was a new metastasis in a 3-year-old child during chemotherapy, which broke the consensus in classic literature that "iris neuroblastoma is more common in infancy" and "metastasis is mostly accompanied by the diagnosis of primary tumor".
Conclusion: Clinical Warning: Rare and rapid iris metastasis may occur in children with neuroblastoma during chemotherapy. Special attention should be paid to ocular monitoring in children under 3 years old (even if they exceed the traditional common age of 1 year), and it is recommended to include ophthalmic examination in the routine assessment during chemotherapy.
Diagnosis and Treatment Strategy: For children with stable condition after primary tumor resection, if vascularized nodules of the iris appear, the possibility of metastasis should be highly suspected, and diagnosis should be confirmed in a timely manner through intraoperative angiography and pathological biopsy. Academic Value: This case is the first report of a rare case of iris metastasis from neuroblastoma in a child over 1 year old, confirming that the chemotherapy period may be a potential window period for intraocular metastasis, and providing new evidence for the early intervention of ocular complications in children with solid tumors.
