title: Practical problems of measuring depth of submucosal invasion in T1 colorectal carcinomas.
abstract: OBJECTIVE
  Submucosal invasion depth (SID) in colorectal carcinoma (CRC) is an important factor in estimating risk of lymph node metastasis, but can be difficult to measure, leading to inadequate or over-extensive treatment. Here, we aimed to clarify the practical aspects of measuring SID in T1 CRC.
  
  
  METHODS
  We investigated 568 T1 CRCs that were resected surgically at our hospital from April 2001 to December 2013, and relationships between SID and clinicopathological factors, including the means of measurement, lesion morphology, and lymph node metastasis.
  
  
  RESULTS
  Of these 568 lesions, the SID was ≥1000 μm in 508 lesions. SIDs for lesions measured from the surface layer were all ≥1000 μm. Although lesions with SIDs ≥1000 μm were associated with significantly higher levels of unfavorable histologic types and lymphovascular infiltration than shallower lesions, a depth of ≥1000 μm was not a significant risk factor for lymph node metastasis (LNM) (6.7 vs. 9.8 %; P = 0.64), and no lesions for which the sole pathological factor was SID ≥1000 μm had lymph node metastasis. Protruded lesions showed deeper SIDs than other types.
  
  
  CONCLUSIONS
  Although we found several problems of measuring SID in this study, we also found, surprisingly, that SID is not a risk factor for lymph node metastasis, and its measurement is not needed to estimate the risk of lymph node metastasis.
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kouyama
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan. kudos@med.showa-u.ac.jp.
authors.forename: Shin-Ei
authors.initials: SE
authors.lastname: Kudo
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Miyachi
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Katsuro
authors.initials: K
authors.lastname: Ichimasa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Hisayuki
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Oikawa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Matsudaira
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Yui J
authors.initials: YJ
authors.lastname: Kimura
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Misawa
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Mori
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Kodama
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Toyoki
authors.initials: T
authors.lastname: Kudo
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Takemasa
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Wakamura
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Katagiri
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Hidaka
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Ishida
authors.affiliation: Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1 Chigasaki Chuo, Tsuzuki-ku, Yokohama City, Kanagawa, 224-8503, Japan.|Department of Pathology, The Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Hamatani
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging
keywords: Invasion depth; Lymph node metastasis; Risk factor; T1 colorectal carcinoma