NCCN Guidelines for Patients® | Esophageal Cancer - page 8

8
NCCN Guidelines for Patients
®
: Esophageal Cancer
Version 1.2013
Part 1: About esophageal cancer
1.1 The esophagus
The digestive system breaks down food for the body to
use. The esophagus is part of this system. It is a tube-
shaped organ, almost 10 inches long, that moves solids
and liquids from your throat to your stomach. It is located
toward the back of your chest just in front of your spine.
See Figure 1 for a picture of the esophagus in the body.
The wall of the esophagus has four main layers. The
inner layer that has contact with food is called the
mucosa. It is made of three sublayers. The epithelium
is tissue that helps protect the esophagus from anything
swallowed. The lamina propria is a thin layer of
connective tissue just behind the epithelium. It contains
blood vessels and glands that make mucus. The
muscularis mucosae is the third sublayer and is
a thin strip of muscle.
The second layer of the esophageal wall is called the
submucosa. It consists of connective tissue and blood
and nerve cells. In some parts of the esophagus, the
submucosa has glands that make mucus.
The third layer is called the muscularis propria. It is
mostly made of muscle fibers. These muscles help move
food down the esophagus.
The fourth layer is called the adventitia. It is mostly made
of connective tissue. It covers the entire esophagus and
connects the esophagus to nearby tissues.
Figure 1. The esophagus
Illustration Copyright © 2013 Nucleus Medical
Media, All rights reserved.
1,2,3,4,5,6,7 9,10,11,12,13,14,15,16,17,18,...100
Powered by FlippingBook