光凝固療法を試みた腎癌原発の転移性脈絡膜腫瘍の1例

Photocoagulation in a case of choroidal carcinoma metastatic from the kidney

　42歳女性が右眼の変視症と進行性の視野欠損で受診した。裸眼視力は右1.0，左1.5であった。右眼底の耳側下方に10乳頭径大の黄色の隆起性病変があり，左眼底の鼻側下方に5乳頭径大の黄色の扁平な病変があった。螢光眼底造影で，点状で始まり拡大癒合する過螢光と，その周囲に低螢光があった。超音波とCT検査で充実性の腫瘍陰影が脈絡膜にあった。全身検査で左腎肥大があり，腎摘出の結果，腎原発の転移性脈絡膜癌と診断した。癌転移は，肺．肝臓，副腎にもあった。存命中の視機能保存を目的として，脈絡膜腫瘍へのアルゴンレーザー光凝固を行った。右眼は網膜全剥離で失明したが，左眼は初診から8か月後に死亡する2か月前には1.2の視力，1か月前には0.4の視力が保持できた。本症例は，腎癌が脈絡膜に転移した稀な例であることと，光凝固が有効であったことが注目される。

A 42-year-old female presented with metamorphopsia and progressive visual field defect in her right eye. Her visual acuity was 1.0 right and 1.5 left. Funduscopy showed a yellow elevated lesion of 10 disc diameters (DD) in the inferior temporal fundus in the right eye and a yellow flat lesion of 5 DD in the inferior nasal fundus in the left. Fluorescein angiography showed hyperfluorescent spots initially which later enlarged to form a confluent mass. A tumorous lesion was detected in the choroid in both eyes by ultrasonography and computed tomography. Systemic examinations showed enlarged left kidney. Surgical removal led to the diagnosis of choroidal carcinoma metastatic from the kidney. Metastases were also present in the lung, liver and adrenal gland. Argon laser photocoagulation was performed to maintain useful vision while the patient was alive. The right eye developed total retinal detachment resulting in blindness. The left visual acuity was 1.2 at 2 months and 0.4 at 1 month before death set in 8 months after her initial visit. This case illustrates that renal carcinoma may metastatize to the choroid as a rare occurrence and that photocoagulation may be effective in preserving the vision.