title: [Pathologically complete response for unresectable stage IV rectal cancer using systemic chemotherapy with panitumumab - a case report].
abstract: We report a case of rectal cancer resulting in a pathologically complete response of the primary tumor by systemic chemotherapy with panitumumab, a new endothelial growth factor receptor(EGFR)antibody. A 56-year-old man was diagnosed as having unresectable Stage IV rectal cancer with local invasion and lung metastasis, and underwent systemic chemotherapy by FOLFOX, combined with panitumumab as a first-line therapy. After 3 courses of FOLFOX and 3 courses of FOLFOX with panitumumab, the treatment regimen was changed to FOLFIRI with panitumumab to prevent peripheral neuropathy. After 5 courses of FOLFIRI with panitumumab, pelvic computed tomography(CT)revealed that the primary tumor was markedly reduced, and the intrapelvic direct invasion was resolved. On the post-treatment chest CT, lung metastasis had disappeared. A low anterior resection preserving the automatic nerves, the colonic J-pouch and anal anastomosis, was performed 20 days after the last chemotherapy. Although the whole tumor-like lesion of the specimen was sectioned macroscopically at 5-mm intervals, no vivid tumor cells were detected at the pathological examination. The patient's postoperative course was uneventful, and no recurrence occurred 5 months after the operation. The EGFR receptor antibody is reported to have a significant anti-cancer effect for colorectal cancer without the KRAS gene mutation. In cases with relatively large tumors especially, EGFR antibody can be an effective first-line treatment.
authors.affiliation: Dept. of Surgery, Nippon Dental University, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Bamba
authors.forename: Takeyasu
authors.initials: T
authors.lastname: Suda
authors.forename: Masato
authors.initials: M
authors.lastname: Nakano
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Terashima
authors.forename: Hajime
authors.initials: H
authors.lastname: Umezu
mesh_terms: D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D000077544:Panitumumab; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000473:pathology* / Q000601:surgery; D012074:Remission Induction; D014057:Tomography, X-Ray Computed
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D000077544:Panitumumab