title: Histological factors contributing to a high risk of recurrence of submucosal invasive cancer (pT1) of the colon and rectum after endoscopic therapy.
abstract: We analyzed the histological high-risk factors for recurrence of submucosal invasive carcinomas (pT1) of the colon and rectum after endoscopic therapy, examining pT1 cancers treated primarily by endoscopic resection within a 23-year period. We compared recurrent and nonrecurrent cancers, evaluating the following "highrisk factors" of the primary lesion: massive invasion, a surgical margin<2 mm but negativity for cancer in the cut end, poorly differentiated adenocarcinoma (PD) (G3), undifferentiated carcinoma (G4), and/or positive angiolymphatic invasion. The following histological factors were defined as predictive of a low risk: minimum invasion, a surgical margin>2 mm, well or moderately differentiated adenocarcinoma (G1, G2), and no evidence of angiolymphatic invasion. We analyzed the records of 37 patients with pT1 cancers, including 15 with high-risk factors who underwent subsequent resection. Local recurrence with or without liver metastases developed in 4 of these 15 patients. The histological type was PD in three (75%) of the four recurrent lesions. All four (100%) lesions showed a desmoplastic response (DR). Only 1 (9%) of the 11 patients without recurrence after subsequent surgery had a lesion with a small component of PD, and only three (27%) lesions showed a mild DR. We concluded that endoscopic therapy is inadequate for pT1 cancers with a histological PD component, and/or a DR in the cancer stroma.
authors.affiliation: Department of Surgery, Tokyo Medical University Kasumigaura Hospital, 3-20-1 Chuo, Ami, Inashiki, Ibaraki, 300-0395, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Nakada
authors.forename: Takanobu
authors.initials: T
authors.lastname: Tabuchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakachi
authors.forename: Jiro
authors.initials: J
authors.lastname: Shimazaki
authors.forename: Satoru
authors.initials: S
authors.lastname: Konishi
authors.forename: Motonobu
authors.initials: M
authors.lastname: Katano
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ubukata
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Goto
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Takafumi
authors.initials: T
authors.lastname: Tabuchi
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D016099:Endoscopy, Gastrointestinal; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D012307:Risk Factors