Asymptomatic marginal zone lymphoma of mucosa-associated lymphoid tissue in the hypopharynx, detected with esophagogastroduodenoscopy oleh Takuya Okada, Kenro Kawada, Taro Sugimoto, Takashi Ito, Kazuya Yamaguchi, Yudai Kawamura, Masafumi Okuda, Yuichiro Kume, Tairo Ryotokuji, Akihiro Hoshino, Yutaka Tokairin, Yasuaki Nakajima