Extramural cancer deposits without nodal structure in colorectal cancer: optimal categorization for prognostic staging.
To establish an optimal categorization of cancer deposits without lymph node structure (extranodal cancer deposits [EX]) in a prognostic staging system, we analyzed 1,027 cases in which patients underwent potentially curative surgery for advanced colorectal adenocarcinoma. EX was classified as vascular invasion-type (VAS) or non-VAS.A total of 512 foci of EX were identified in 205 patients (20.0%), with VAS and non-VAS found in 68 and 182 patients, respectively. The hazard ratio for patients with nodal involvement was 3.6 and for patients with VAS and non-VAS, 2.5 and 4.7, respectively. Based on multivariate analysis of these 3 parameters, only nodal involvement and non-VAS were significant prognosticators. By using the Akaike information criterion, N staging was capable of predicting survival outcome with the highest accuracy when both nodal involvement and non-VAS were treated together as an N factor and VAS was treated as a T factor ("new categorization"). The clinical significance of the TNM grading system for colorectal cancer would be enhanced if we treat EX as a new categorization.
Ueno
Hideki
H
Department of Surgery, National Defense Medical College, Namiki, Tokorozawa, Saitama, Japan.
Mochizuki
Hidetaka
H
Hashiguchi
Yojiro
Y
Ishiguro
Megumi
M
Miyoshi
Masayoshi
M
Kajiwara
Yoshiki
Y
Sato
Taichi
T
Shimazaki
Hideyuki
H
Hase
Kazuo
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000473:pathology; D015179:Colorectal Neoplasms / Q000145:classification / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology; D016019:Survival Analysis