Chapter 31 - Colon and Appendix (CHERI NOTES) Flashcards
TRUE OR FALSE.SINGLE CONTRAST BARIUM ENEMA is still occasionally used for the evaluation of colonic obstruction; fistulas and in old; seriously ill or debilitated patients. (p. 780)
TRUE
TRUE OR FALSE.
DOUBLE-CONTRAST (air contrast) barium enema is favored for detection of small lesions (< 1 cm); for documentation of
inflammatory bowel disease and for detailed imaging evaluation of the rectum. (p.780)”
TRUE
___ complements colonoscopy and barium examinations
by demonstrating intramural and extracolonic components of
disease. (p.780)
- it is excellent for demonstrating extrinsic inflammatory
and neoplastic processes that affect the colon:
abscesses; sinuses and fistulas.
CT
- Colonoscopy is sporadically limited by occasional failure
to reach the right colon - then; barium enema or virtual colonoscopy is utilized to
complete the examination.
_____ is more accurate than CT or MR in determining local tumor
extent of rectal carcinomas and is used in the evaluation of other
rectal and perirectal diseases. (p.780)
TRANSRECTAL ULTRASOUND
_____ refers to a radiolucency in a barium pool caused by a
protruding mass lesion. (p.781)
FILLING DEFECT
- on barium enema examinations; filling defects may be POLYPS;
TUMORS; PLAQUES; AIR BUBBLES; FECES; MUCUS or FOREIGN
OBJECTS.
____ are protrusions from the mucosa that produce filling defects
in defects in pools of barium or are etched in white when coated
by barium and outlined by air on double-contrast studies. (p.781)
POLYPS
- may be pedunculated on a stalk or sessile
- they may appearr as “BOWLER HATS” when viewed obliquely
- the term “polyp” is a generic for a protruding lesion and does
not imply a histologic diagnosis.
Air bubbles rise to the highest point of a contrast column
(the “_____ sign”); but fecal material usually remains
dependent. (p.781-782)
CARPENTER’S LEVEL SIGN
- Plaques are flat lesions that barely rise above the mucosal
surface.
_____ is the most common malignancy of the GI tract and the
second most common malignancy in the U.S. (p.782)
COLORECTAL ADENOCARCINOMA
Approximately 50% of Colorectal CA arise in the
___ and __ area. (p.782)
RECTUM and RECTOSIGMOID AREA
- another 25% occur in the sigmoid colon; and
the remaining 25% are evenly distributed
throughout the remainder of the colon. - nearly all cancers of the colon are
adenocarcinomas arising from preexisting
adenomas - most tumors are annular constricting lesions;
2 to 6 cm in diameter; with raised everted edges
and ulcerated mucosa.
TRUE OR FALSE.
Polypoid tumors are less common; some having the
frond-like appearance of villous carcinoma. (p.782)
TRUE
- INFILTRATING SCIRRHOUS TUMORS; so common in gastric CA;
are rare in the large intestine; unless the patient has ulcerative
colitis. (p.782) - the tumor spreads by direct invasion through the bowel wall
into pericolonic fat and adjacent organs; lymphatic channels to
regional nodes and hematogeneously through the portal veins
to the liver and systemic circulation.
TRUE OR FALSE.
In colorectal adenoCA; INTRAPERITONEAL SEEDING from a tumor
that penetrates the colon wall may also occur. (p.782)
TRUE
__ is the most frequent complication of colorectal adenoCA (p.782)
OBSTRUCTION
- other complications are uncommon but include perforation;
instussusception; abscess and fistula formation. - up to 20% of patients have a second tumor of the large bowel
at diagnosis; usually an adenoma or another carcinoma. - approximately 5% of patients will have a second colorectal
CA either simultaneously or subsequently diagnosed.
TRUE OR FALSE.
Patients with ulcerative colitis; Crohn Disease; Familial
adenomatous polyposis syndrome and Peutz-Jeghers syndrome
are at increased risk of colon carcinoma. (p.783)
TRUE
Local disease staging of Colorectal AdenoCA is best evaluated
with ____ or ______. (p.783)
TRANSRECTAL or COLONOSCOPIC
ULTRASOUND
- CT and MR are used for more advanced
disease and to detect recurrence. - microscopic invasion through the bowel wall
andd tumor involvement of normal sized lymph
nodes is not detected by CT or MR.
DIAGNOSIS? (colon) (p.783)
Cross-sectional imaging findings include:
1. Polypoid primary tumor (usually >1 cm)
2. “Apple-core lesions” with bulky; irregular thickening of the
colon wall and irregular narrowing of the lumen.
3. Cystic; necrotic and hemorrhagic areas within the tumor mass;
esp. when the tumor is large.
4. Linear soft tissue stranding into the pericolonic fat often
indicative of tumor extension through the bowel wall
5. Enlarged regional lymph nodes (>1 cm) representing
lymphatic spread of tumor
6. Distant metastases; esp. in the liver.
COLORECTAL ADENOCARCINOMA
- When tumor cause colonic
obstruction;edema or ischemia may thicken
the wall of the uninvolved colon
proximal to the tumor.
4 most common sites of tumor reccurences in COLORECTAL
ADENOCARCINOMA? (p.783)
1. AT THE OPERATIVE SITE; near the bowel anastomosis 2. IN LYMPH NODES that drain the operative site 3. IN THE PERITONEAL CAVITY 4. IN THE LIVER AND DISTANT ORGANS
- The entire abdominal cavity must
be surveyed to detect tumor recurrence - CT; MR and PET-CT are utilized to demonstrate
response to therapy and tumor recurrence
A ____ is defined as a localized mass that projects from the
mucosa into the lumen. (p.783)
POLYP
- because the majority of colorectal cancers are believed to arise from pre-existing adenomatous polyps; the detection of polyps is a major indication for colonosocpy and imaging studies of the colon.
TRUE OR FALSE.
- Polyps less than 5 mm are almost all hyperplastic;
with a risk of malignancy less than 0.5%.
- Polyps 5 to 10 mm in size are 90% adenomas;
with a risk of malignancy of 1% - Polyps 10 to 20 mm in size are 90% adenomas;
with a risk of malignancy of 10% - Polyps larger than 20 mm are 50% malignant
TRUE
_____ polyps are nonneoplastic mucosal proliferation.
They are round and sessile. Nearly all are less than 5 mm in size.
(p.783)
HYPERPLASTIC POLYPS
_____ polyps are distinctly premalignant and a major risk for
development of colorectal carcinoma. (p.783)
ADENOMATOUS POLYPS
- these are neoplasms with a core of connective tissue - approximately 5% to 10% of population older than 40 years have adenomatous polyps
\_\_\_\_\_\_\_ polyps (\_\_\_\_\_\_ polyps) represent 1% of colon polyps. They are a common cause of rectal bleeding in CHILDREN. (p.783)
HAMARTOMATOUS POLYPS
(JUVENILE POLYPS)
- The Peutz-Jeghers polyp is a
type of hamartomatous polyp.
_____ polyps are usually multiple and associated with inflammatory
bowel disease. They account for less than 0.5% of colorectal polyps.
(p.783)
INFLAMMATORY POLYPS
TRUE OR FALSE.
FAMILIAL ADENOMATOUS POLYPOSIS SYNDROME is approx.
two-thirds inherited and one-third spontaneous. (p.784)
- Polyps typically carpet the entire colon.
TRUE
- the inheritance pattern is AUTOSOMAL DOMINANT with high penetrance - the polyps are tubulovillous adenomas; which usually are evident by age 20. - Colorectal cancer will eventually develop in nearly all patients; and so; total colectomy with rectal mucosectomy and ileoanal pouch construction is the current recommended therapy.
TRUE OR FALSE.
In FAMILIAL ADENOMATOUS POLYPOSIS SYNDROME
- patients are at risk for numerous extracolonic
manifestation including carcinomas of the small
bowel; thyroid carcinoma; and mesenteric
fibromatosis. (p.784)
TRUE
FAMILIAL ADENOMATOUS POLYPOSIS SYNDROME patients with
associated bone and skin abnormalities including cortical
thickening of the ribs and long bones; osteomas of the skull;
supernumerary teeth; exostoses of the mandible; and dermal
fibromas; desmoids; and epidermal inclusion cysts have
been diagnosed as _____ syndrome. (p.784)
GARDNER SYNDROME
FAMILIAL ADENOMATOUS POLYPOSIS SYNDROME patients with
associated tumors of the CNS have been grouped as
_____ syndrome. (p.784)
TURCOT SYNDROME
_____ polyps are nonneoplastic growths with a smooth muscle core
covered by mature glandular epithelium. (p.784)
HAMARTOMATOUS POLYPS
- however; patients with the hamartomatous
polyposis syndromes may also
develop adenomatous polyps;
which do carry a risk of malignancy.
TRUE OR FALSE.
PEUTZ-JEGHERS SYNDROME predominantly involves the SMALL BOWEL;
but most cases have gastric and colon polyps as well.
TRUE
- the condition is autosomal dominant with incomplete penetrance. - dark pigmented spots on the skin and the mucosal membranes are characteristic. - risk of carcinoma arising from coexisting adenomatous polyps is 2% to 20% - patients are also at risk for breast CA; uterine and ovarian CA and early age cancer of the pancreas.
_____ is a syndrome of multiple hamartomas including
hamartomatous polyposis of the GI tract; WITH GOITER AND
THYROID ADENOMAS and increased risk of breast cancer
and transitional cell carcinoma of the urinary tract. (p.784)
COWDEN DISEASE
- The syndrome is autosomal dominant and affects mainly Caucasians
- all patients have mucocutaneous lesions with facial papules; oral papillomas and palmoplantar keratoses
_____ syndrome is a disease of OLDER PATIENTS with a
mean age of onset of 60 years. (p.784)
- polyps are distributed througout the stomach; small bowel; and colon.
CRONKHITE-CANADA SYNDROME
- associated skin findings include nail atrophy; brownish skin pigmentation and alopecia.
- patients present with watery diarrhea and protein-losing enteropathy.
TRUE OR FALSE.
LYMPHOID HYPERPLASIA may involve the colon. The normal
lymphoid follicular pattern of diffuse tiny nodules 1 to 3 mm in
diameter with characteristic umbilication is most common in the
TERMINAL ILEUM AND CECUM but may involve any portion of the
colon.
TRUE
- the nodular lymphoid hyperplasia pattern of diffuse nodules larger than 4 mm is associated with allergic; infectious; and inflammatory disorders.
TRUE OR FALSE.
Involvement of the cecum or rectum is most common with
anal and rectal lymphoma increasingly frequent in AIDS patients.
(p.784)
TRUE
- the colon is less commonly involved with lymphoma than the stomach or small bowel. - most are non-hodgkin b-cell lymphoma. - morphologic patterns include small to large nodules that may ulcerate; excavate and perforate and diffuse infiltration of the bowel wall resulting in bulbous folds and thickened bowel wall.
TRUE OR FALSE.
LYMPHOMA NODULES vary in size although LYMPHOID HYPERPLASIA
NODULES are uniform in size. (p.785)
TRUE
- the diffuse multinodular form may be
difficult to differentiate from nodular
lymphoid hyperplasia.
TRUE OR FALSE.
(In colonic lymphoma); as in the small intestine; marked
narrowing of the lumen is uncommon; aneurysmal
dilation occurs when transmural disease destroys innervation.
TRUE
____ account for nearly all mesenchymal tumors of the colon.
p.785
GI stromal tumors (GISTs)
- true colonic leiomyomas and leiomyosarcomas are very rare - GISTs are much less common in the colon than in the stomach and small bowel accounting for only 7% of the total. - as in the remainder of the GI tract they may appear as exophytic; mural or intramural masses. - ulceration is relatively frequent. - hemorrhagic; cystic change; necrosis and calcifications are more common in larger tumors.
____ is the most common submucosal tumor of the colon. (p.785)
LIPOMA
- barium studies demonstrate a smooth; well-defined elliptical filling defect; usually 1 to 3 cm in diameter. - the tumors are soft and change shape with compression. - CT demonstration of a fat density tumor is definitive.
2 most frequent locations of the colonic lipomas. (p.785)
CECUM and ASCENDING COLON
- nearly 40% present with intussusception
TRUE OR FALSE.
EXTRINSIC MASSES commonly cause mass effect on the colon
that may simulate intrinsic disease. (p.785)
TRUE
TRUE OR FALSE.
ENDOMETRIOSIS commonly implants on the sigmoid colon and
the rectum. (p.785)
TRUE
- defects are frequently multiple
and of variable size. - lesions are commonly within
the cul-de-sac
* barium studies demonstrate sharply defined defects that compress but do not usually encircle the lumen. * CT demonstrates complex cystic pelvic masses with high- density fluid components. Multiple pelvic organs may be incorporated into the mass. * MR demonstrates masses with signal characteristics of hemorrhage.
______ such as ovarian cysts ; cystadenomas; teratomas; and
uterine fibroids produce smooth extrinsic mass impressions of the
colonic wall. The colon is displaced but not invaded. (p.785)
BENIGN PELVIC MASSES
MALIGNANT PELVIC TUMORS and METASTASES may involve the
colon by these 3 ways. (p.785)
- the involved colon demonstrates thickening of the wall;
separation of folds; spiculation; angulations; narrowing and
serosal plaques.
1. BY CONTIGUOUS SPREAD; spread along mesenteric fascial planes 2. BY INTRAPERITONEAL SEEDING; through lymphatic channels 3. BY EMBOLUS through blood vessels.
- metastases oten cannot be
differentiated from primary
tumors by imaging methods
TRUE OR FALSE.
Crohn disease and metastatic disease may also look exactly
alike radiographically. (p.785)
TRUE
-CT or MR demonstrates contiguous involvement
of the colon and the rectum by pelvic tumors.
______ is an uncommon idiopathic inflammatory disease
involving primarily the mucosa and submucosa of the colon.
ULCERATIVE COLITIS
- the peak for its appearance is 20 to 40 years;
but onset of disease after age 50 is common. - the disease consists of superficial ulcerations;
edema and hyperemia.
4 Radiographic hallmarks of Ulcerative Colitis. (p.785-786)
- Granular mucosa
- Confluent shallow ulcerations
- Symmetry of disease around
the lumen - Continuous confluent diffuse
involvement
- an early fine; granular pattern is produced by mucosal hyperemia and edema that precedes ulceration. - superficial ulcers spread to cover the entire mucosal surface - the mucosa is stippled with barium adhering to the superficial ulcers.
____ ulcers are deeper ulcerations of thickened edematous
mucosa with crypt abscesses extending into the submucosa. (p.786)
COLLAR BUTTON ULCERS
- A coarse granular pattern is produced later by the replacement of diffusely ulcerated mucosa with granulation tissue. - late changes include a variety of polypoid lesions.
____polyps are mucosal remnants in areas of extensive ulceration.
(p.786)
PSEUDOPOLYPS
