Adenocarcinoma

October 13, 2011

A 56-year-old female presented with abdominal pain, R/O colitis. There is a long segment of asymmetrical wall thickening seen involving the ascending colon just above the ileocaecal region to proximal third of transverse colon associated with luminal narrowing and significant surrounding fat stranding and enlarged regional lymph node.

Clinical History

56-year-old female presented with abdominal pain, R/O colitis.
 

CT Findings

There is a long segment of asymmetrical wall thickening seen involving the ascending colon just above the ileocaecal region to proximal third of transverse colon associated with luminal narrowing and significant surrounding fat stranding and enlarged regional lymph node.

There is small focal collection noted measuring about 3 x 2 x 2.3 cm in the AP, transverse and craniocaudal diameter situated inferior to the proximal portion of the transverse colon.

There is no associated proximal wall dilatation or bowel obstruction. Diverticulosis of the left hemicolon is noted.

Pathology

Right colon removed along with lymphnodes.

Adenocarcimona, moderately differentiated, ulcerated.

Discussion

All most all colon cancers are primary adenocarcinomas, which are the third most common cancer in both men and women in North America and Western Europe.

Colon cancers are the most common gastrointestinal (GI) carcinomas and have the best
prognosis. The 5-year survival rates of approximately 50 percent may be improved by screening and removal of adenomatous polyp.

 

 

 

 

 

 

 

 

 

 

Classification Systems

The prognosis of patients with colon cancer relates to the stage of the disease at the time of diagnosis and to initial treatment. Although a tumor, node, metastasis(TNM)–based international classification and a computed tomography (CT) staging system have been developed, the Dukes classification (or one of its modifications) is widely used. Prognosis is also affected by the histologic grade of the tumor.

The complications of colon cancer include obstruction (common), perforation (uncommon), intussusception and ischemic colitis proximal to an obstructing tumor (rare), and fistula formation in the small bowel, bladder, or vagina (rare).
 

Table 1. Dukes Classification and 5-Year Survival (modified from Zinkin) 

Stage Description 5-Year Survival
ALimited to the bowel wall83%
B Extension to pericolic fat; no nodes70%
CRegional lymph node metastases30%
DDistant metastases (liver, lung, bone)10%

 

Table 2. CT Scan Staging System for Colon Cancer
* Modified from Thoeni.  

StageDescription
T1Intraluminal polypoid mass; no thickening of bowel wall
T2Thickened colon wall > 6 mm; no periodic extension
T3aThickened colon wall plus invasion of adjacent muscle or organs
T3bThickened colon wall plus invasion of pelvic side wall or abdominal wall
T4Distant metastases, usually liver, lung, or adrenal glands

 

Table 3. TNM/Modified Dukes Classification System
*American Joint Committee on Cancer 

TNM StageModified Dukes Stage Description
T1 N0 M0 ALimited to submucosa
T2 N0 M0 B1 Limited to muscularis propria
T3 N0 M0 B2Transmural extension
T2 N1 M0C1T2, enlarged mesenteric nodes
T3 N1 M0C2T3, enlarged mesenteric nodes
T4 C2Invasion of adjacent organs
Any T M1 D Distant metastases

 

Sushila Ladumor, MD, FRCR, Consultant Radiologist with Multi-modality Imaging experience, working in Medical Imaging Department, King Abdulaziz Medical City, Riyadh, Saudi Arabia.  

References

http://emedicine.medscape.com/article/367061-overview#a22
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Thoeni RF, Moss AA, Schnyder P. Detection and staging of primary rectal
and rectosigmoid cancer by computed tomography. Radiology. Oct
1981;141(1):135-8. [Medline].