title: Deep infiltrative low-grade MALT (mucosal-associated lymphoid tissue) colonic lymphomas that regressed as a result of antibiotic administration: endoscopic ultrasound evaluation.
abstract: Since 1997 we have experienced three cases of low-grade colonic mucosal-associated lymphoid tissue (MALT) lymphomas. The depth of tumor invasion was evaluated by endoscopic ultrasonography (EUS) and the mass lesions were all diagnosed as having extended beyond the deep region of the submucosal layer. Although all of these patients tested negative for gastric Helicobacter pylori, their tumor lesions regressed after antibiotic treatment in accordance with H. pylori eradication therapy. In general, consensus has been reached regarding antibiotic therapy for gastric MALT lymphomas. However, as a prerequisite for antibiotic therapy, the therapy has been deemed effective against these gastric tumors if the extent of infiltration, as evaluated by EUS, is limited to the mucosal layer or the superficial region of the submucosal layer. Based on the therapeutic outcomes seen in the three patients studied here, it is suggested that antibiotic therapy might be useful in treating MALT lymphomas of the colon, even in patients with advanced invasive tumors, in contrast to the extent of the lesions in the stomach suitable for antibiotic treatment. The success of the antibiotic treatment also suggests that MALT lymphomas may be caused by unknown luminal microorganisms, other than H. pylori.
authors.affiliation: Department of Gastroenterology, Fukuoka University Chikushi Hospital, 377-1 Ohaza Zokumyoin, Chikushino, 818-5807, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Kikuchi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Matsui
authors.forename: Takashi
authors.initials: T
authors.lastname: Hisabe
authors.forename: Yoko
authors.initials: Y
authors.lastname: Wada
authors.forename: Toshio
authors.initials: T
authors.lastname: Hoashi
authors.forename: Sumio
authors.initials: S
authors.lastname: Tsuda
authors.forename: Tsuneyoshi
authors.initials: T
authors.lastname: Yao
authors.forename: Akinori
authors.initials: A
authors.lastname: Iwashita
authors.forename: Kensaburo
authors.initials: K
authors.lastname: Imamura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017291:Clarithromycin / Q000627:therapeutic use; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000382:microbiology; D019160:Endosonography; D005260:Female; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000382:microbiology; D008297:Male
chemical_list: D000900:Anti-Bacterial Agents; D000658:Amoxicillin; D017291:Clarithromycin