title: Proposed objective criteria for "grade 3" in early invasive colorectal cancer.
abstract: To establish objective criteria for "grade 3" (G3) in T1 (TNM staging) colorectal cancer (CRC), a total of 296 T1 CRC cases were reviewed. The incidence of nodal involvement differed most greatly between G3 and non-G3 (21/27 [27%] and 6/162 [3.7%], respectively; P < .0001), when G3 was applied to tumors containing either or both of the following: (1) 10 or more solid cancer nests in the microscopic field of a 4x objective lens and (2) a mucin-producing component fully occupied the microscopic field of a 40x objective lens. Regarding G3, vascular invasion, and tumor budding as indicating the risk of metastasis, nodal involvement rate was 21.0% in the tumors with 1 or more risk factors, whereas it was only 1.7% in the no-risk tumors (P < .0001). In patients treated with local excision only, nodal recurrence occurred in 3 (20%) of 15 risk-positive patients, whereas none of 42 patients without risk factors had nodal recurrence (P = .016). In cases of locally excised T1 CRC, G3 as determined by the proposed criteria, vascular invasion, and budding would comprise a useful combination of parameters for determining the indication for additional laparotomy.
authors.affiliation: Dept. of Surgery, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ueno
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Hashiguchi
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Kajiwara
authors.forename: Eiji
authors.initials: E
authors.lastname: Shinto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Shimazaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kurihara
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Mochizuki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hase
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000145:classification* / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D009367:Neoplasm Staging; D011379:Prognosis
chemical_list: D009077:Mucins