粘膜下浸潤を認めた微小食道扁平上皮癌の2例

Minute Invasive Squamous Cell Carcinoma of the Esophagus Associated with Head and Neck Cancer, Report of Two Cases

要旨　下咽頭癌を合併した粘膜下浸潤を呈する5mm以下の微小食道扁平上皮癌の2例を経験した．いずれも，水平方向への癌の発育は乏しく垂直下方への発育が顕著であった．これらは，食道扁平上皮癌の発育を考えるうえで，早い段階から垂直下方への発育を主にする発育形式をとるものがあることを示唆すると考える．また，頭頸部癌や食道癌症例において，しばしば食道内の多発ヨード不染帯を認めるが，本症例も周囲食道粘膜に大小様々な多発ヨード不染帯を伴っていた．多発ヨード不染帯を伴う症例の場合，すべてのヨード不染帯を組織学的に検討することは物理的に不可能であり，これらの臨床的な取り扱いが問題となる．本症例は，多発ヨード不染帯を伴う症例を5mm程度の不染帯を含めてどう扱うかを考えるうえでも貴重な症例である．

　We reported two cases of minute invasive squamous cell carcinoma of the esophagus (ESCC) associated withhypolaryngeal cancer, in which sizes of ESCC were 5 mm and 4 mm, respectively. In both cases, invasion of cancer cells vertically into the submucosa was remarkable compared to the horizontal spread. This finding suggests that some ESCCs can invade vertically with-out horizontal spread in their infancy.

　In the cases of head and neck cancer and ESCC, we frequently observed multiple lesions in the esophagus unstained by iodine. The cases presented here also had such lesions. However, it is impossible to examine all of the lesions histologically and it has not been clear how we should manage these lesions. Our cases might provide an important implication for the management of multiple lesions in the esophagus unstained by iodine including minute lesions less than 5 mm in diameter.