testinal & in D o i tr g s e a s

t

G i v

f Journal of Gastrointestinal & Digestive

e Tanaka et al., J Gastroint Dig Syst 2013, S12

o

S

l

y

a

s

n

r

ISSN: 2161-069Xt

e DOI: 10.4172/2161-069X.S12-011 u m o

J System

Commentary Open Access Marked Characteristics of the Related to Surgical Treatment Tanaka E*, Noguchi T, Nagai K and Shimada T Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu-city, Oita, 879-5593, Japan

In our previous study, the epithelium of the lower and the anal canal in the adult human was examined by means of light and scanning electron microscopy (LM and SEM) [1]. The epithelium of the surgical anal canal was basically composed of the simple columnar epithelium and the stratified squamous epithelium, and their borderline was the anorectal line. We found no evidence demonstrating the presence of the anal transitional zone, whereas the duct of the anal gland, the anal crypt and sinus exceptionally consisted of the stratified columnar epithelium. The anorectal line was the line at which the simple columnar epithelium in the rectum came to an end. Accordingly, it seems reasonable that the anorectal line is regarded as the terminal of the . In addition, the anorectal line might be the boundary between the endodermal part and the ectodermal part of the anal canal. We proposed that the area from the anorectal line to the anal Figure 3: Stratified columnar epithelium (HE staining). Bar=60μm. intersphincteric groove with the should be considered and treated as an organ against the rectum (like the against the ). Because the epithelium of this area was basically composed of one epithelial type and accompanied by the lamina . When we temporarily defined this area as ‘the anal canal’, it seemed to be simple and easy to recognize. Figure 1 is a simplified schema showing the epithelium of the surgical anal canal, based on LM and SEM images. Figure 2 shows a longitudinal section obtained through the anal sinus, which reveals the relationship among the anal glands, the duct of the anal glands, and the anal sinuses. Figures 3 and 4 show the stratified columnar epithelium [1].

Figure 4: Stratified columnar epithelium (SEM). Bar=6μm.

In general, tumors in the anal canal were various in pathological types and patterns. This may arise from the presence of several epitheliums in the narrow area. The epithelium of ‘the anal canal’ was fundamentally composed of one epithelial type, the stratified squamous epithelium. However the existence of a series of secretory glands (the anal gland, the anal duct, the anal crypt and sinus) causes a wide variety Figure 1: A simplified schema showing the epithelium of the surgical anal canal based on LM and SEM.

*Corresponding author: Tanaka E, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu-city, Oita, 879-5593, Japan, Tel: +81-97-586- 5854; Fax: +81-97-586-6449; E-mail: [email protected]

Received April 30, 2013; Accepted June 06, 2013; Published June 08, 2013

Citation: Tanaka E, Noguchi T, Nagai K, Shimada T (2013) Marked Characteristics of the Anal Canal Related to Surgical Treatment. J Gastroint Dig Syst S12: 011. doi:10.4172/2161-069X.S12-011

Figure 2: A longitudinal section through the anal sinus (HE staining). Copyright: © 2013 Tanaka E, et al. This is an open-access article distributed under Bar=300μm StSq; Stratified squamous ep., StCo; Stratified columnar ep., the terms of the Creative Commons Attribution License, which permits unrestricted SiCo; Simple columnar ep. use, distribution, and reproduction in any medium, provided the original author and source are credited.

J Gastroint Dig Syst Gastrointestinal Cancer ISSN: 2161-069X, an open access journal Citation: Tanaka E, Noguchi T, Nagai K, Shimada T (2013) Marked Characteristics of the Anal Canal Related to Surgical Treatment. J Gastroint Dig Syst S12: 011. doi:10.4172/2161-069X.S12-011

Page 2 of 2 of pathological features of malignant tumors in the anal canal. When good. We have no objection to the established theory that the internal we make clinical and pathological studies of cancers in the anal canal, anal sphincter collaborates with the and the we suggest that we should consider the marked characteristics of the levator ani in continence. However we suppose that the anal sphincter origin. might play a supplementary role. We are watching functional results of ISR with great interest. ‘The anal canal’ plays a role in continence as the internal anal sphincter. Fichera et al. performed a stapled IPAA with preservation References of the anal transitional zone (ATZ), preservation of ‘the anal canal’ in 1. Tanaka E, Noguchi T, Nagai K, Akashi Y, Kawahara K, et al. (2012) Morphology our study, for ulcerative colitis [2]. The result was that preservation of the epithelium of the lower rectum and the anal canal in the adult human. Med Mol Morphol 45: 72-79. of the ATZ offered excellent defecatory function and quality of life. Intersphincteric resection (ISR) removes the internal anal sphincter; in 2. Fichera A, Ragauskaite L, Silvestri MT, Elisseou NM, Rubin MA, et al. (2007) Preservation of the anal transition zone in ulcerative colitis. Long-term effects a sense ISR removes ‘the anal canal’. Yamada et al. performed ISR for on defecatory function. J Gastrointest Surg 11: 1647-1652. low rectal cancer and assessed the long–term results after surgery in 3. Yamada K, Ogata S, Saiki Y, Fukunaga M, Tsuji Y, et al. (2009) Long-term terms of level of maintenance of the defecatory function etc [3]. As a results of intersphincteric resection for low rectal cancer. Dis Colon Rectum result; defecatory function and continence after ISR were objectively 52: 1065-1071.

This article was originally published in a special issue, Gastrointestinal Cancer handled by Editor(s). Dr. Aliasger Amin, James Cook University Hospital Middlesbrough, United Kingdom

J Gastroint Dig Syst Gastrointestinal Cancer ISSN: 2161-069X, an open access journal