下咽頭に発生したMALTリンパ腫の1例

A case of MALT lymphoma of the hypopharynx

はじめに

　Mucosa-associated lymphoid tissue（MALT）リンパ腫は，粘膜関連リンパ組織を発生母地とする低悪性度B細胞性リンパ腫の一種である。頭頸部領域は，消化管，肺に次ぐ好発部位とされているが，下咽頭における発生はきわめて稀である。今回われわれは，右梨状陥凹に発生したMALTリンパ腫の1例を経験したので，文献的考察を含めて報告する。

　A 79-year-old woman presented with a feeling of a lump in the throat and she was referred to Hakodate Goryokaku Hospital. Fiberoptic examination revealed a spherical, movable tumour in the right pyriform sinus, and direct laryngoscopy was performed for tumour resection under general anesthesia. Pathologically, the specimen consisted of an infiltration of small lymphoid cells and plasma cells with low-grade nuclear atypia and of characteristic lymphoepithelial lesions, and the tumor cells showed kappa light chain restriction, which was consistent with MALT lymphoma. There was no recurrence during the 44 months follow-up period.