title: Laparoscopic resection of a gastrointestinal stromal tumor of the rectum after treatment with imatinib mesylate: report of a case.
abstract: This report describes the laparoscopic resection of a rectal GIST after treatment with imatinib mesylate. A 56-year-old male presented with a submucosal tumor (longest diameter, 8 cm) arising in the lower rectum. A core needle biopsy revealed that the tumor contained bundles of spindle-like cells. Immunostaining revealed that the tumor was positive for c-kit and CD34. Analysis of the c-kit gene revealed a substitution of ACA (threonine) by GCA (alanine) at codon 574 of exon 11. Imatinib mesylate (400 mg/day) was given as preoperative adjuvant therapy for 3 months, and the tumor shrank to 5 cm in diameter. Proctectomy with transanal anastomosis could be performed laparoscopically, while preserving the anus. There was no evidence of recurrence 2 years 6 months after surgery. Preoperative adjuvant chemotherapy with imatinib mesylate may permit the use of less invasive treatment procedures, allowing anal preservation.
authors.affiliation: Department of Surgery, School of Medicine, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara Kanagawa, 252-0374, Japan. midoris@med.kitasato-u.ac.jp
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Nakamura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mitomi
authors.forename: Wataru
authors.initials: W
authors.lastname: Onozato
authors.forename: Takeo
authors.initials: T
authors.lastname: Sato
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ikeda
authors.forename: Masanori
authors.initials: M
authors.lastname: Naito
authors.forename: Naoto
authors.initials: N
authors.lastname: Ogura
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kamata
authors.forename: Akira
authors.initials: A
authors.lastname: Ooki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage; D001549:Benzamides; D044963:Biopsy, Fine-Needle; D003082:Colectomy / Q000379:methods; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000188:drug therapy / Q000473:pathology / Q000601:surgery*; D006801:Humans; D000068877:Imatinib Mesylate; D007150:Immunohistochemistry; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D010879:Piperazines / Q000008:administration & dosage*; D011300:Preoperative Care / Q000379:methods; D011743:Pyrimidines / Q000008:administration & dosage*; D012004:Rectal Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000601:surgery*; D018570:Risk Assessment; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate