渦静脈浸潤がみられたぶどう膜悪性黒色腫の2例

Clinical courses of 2 cases of uveal melanoma with vortex vein invasion

要約　目的：渦静脈浸潤がみられたぶどう膜悪性黒色腫2症例の経過を報告する。

症例1：67歳，女性。右眼内腫瘍の診断で当科を紹介され初診。右眼毛様体付近に腫瘍高12mm大の黒色腫瘤を認めた。ぶどう膜悪性黒色腫と診断し，初診から20日後に眼球摘出術を施行。病理診断はぶどう膜悪性黒色腫で，渦静脈浸潤がみられた。眼球摘出後7か月で結膜下に局所再発を生じたため腫瘤のみを一塊にして摘出し，後療法としてインターフェロンβ（IFN-β）結膜下注射を施行した。眼球摘出後9か月で肝転移が生じ，肝動脈化学塞栓療法および免疫チェックポイント阻害薬（ICI）による加療が行われたが，肝転移診断後7か月で死亡した。

症例2：69歳，女性。右眼内腫瘍の診断で当科を紹介され初診。右眼内に腫瘍高8.5mmの黒色腫瘤を認めた。ぶどう膜悪性黒色腫と診断し，初診から13日後に眼球摘出術を施行。術中所見で黒色に変色した渦静脈が認められた。病理診断はぶどう膜悪性黒色腫で，渦静脈として提出した検体にも腫瘍細胞が認められた。後療法としてIFN-β結膜下注射を施行した。眼球摘出後12か月で多発肝転移を生じ，ICIによる加療が行われたが，肝転移診断後12か月で死亡した。

結論：ぶどう膜悪性黒色腫の渦静脈浸潤例は局所再発・肝転移の高リスク症例であり，後療法の確立が望まれる。

Abstract　Purpose：We report two cases of uveal melanoma associated with vortex vein invasion.

Case 1：A 67-year-old woman presented to our hospital diagnosed with a right intraocular tumor. Evaluation showed a black mass（12 mm in height）near the right ciliary body. She was clinically diagnosed with uveal melanoma and underwent enucleation 20 days after the first visit. Histopathological evaluation confirmed diagnosis of uveal melanoma with vortex vein invasion. Local recurrence occurred beneath the conjunctiva, 7 months after enucleation. We performed surgical resection followed by post-treatment interferon-β（IFN-β）conjunctival injection. The patient developed liver metastasis 9 months after enucleation and underwent transcatheter arterial chemoembolization and immune checkpoint inhibitor（ICI）therapy. However, she died 7 months after diagnosis of liver metastasis.

Case 2：A 69-year-old woman presented to our hospital diagnosed with a right intraocular tumor. Evaluation showed a black mass（8.5 mm in height）at the right eye fundus. She was clinically diagnosed with uveal melanoma and underwent enucleation 13 days after the first visit. Intraoperatively, we observed blackened blood vessels, with suspected invasion of vortex veins. Histopathological evaluation confirmed diagnosis of uveal melanoma without venous invasion；however, vortex invasion was strongly suspected in clinical course. She was administered post-treatment IFN-β conjunctival injection. The patient developed multiple liver metastases 12 months after enucleation and was treated with ICI therapy；however, she died 12 months after the diagnosis of liver metastasis.

Conclusion：Uveal melanoma accompanied by vortex vein invasion is associated with a high risk of local recurrence and liver metastasis；thus establishing an optimal postoperative therapeutic regimen in such cases is important.