7. Colon cancer

Question 1

COLORECTAL CANCER ?

Answer 1

• 3rd most common cancer in Poland.

- 2nd cause of cancer death in men, 3rd in women.

Question 2

FAP-Familial adenomatous polyposis :

Answer 2

• Autosomal dominant inherited disease due to mutation of the APC(adenomatous polyposis coli) gene.
• More than 100 colonic adenomas are diagnostic.
• The risk of colorectal cancer is 100% in patients with FAP. Surgery is the only mean of preventing colonic cancer.

Question 3

Hereditary non-polyposis colorectal cancer (Lynch’s syndrome) ?

Answer 3

• Autosomal dominant condition caused by a mutation in one of the DNA mismatch repair genes MLH1, MSH2, MSH6, PMS and PMS2.

Question 4

CANCEROUS COLORECTAL POLYP ?

Answer 4

○ Superficial carcinoma:

• no involvement of the muscularis mucosa
• non-invasive, non-metastatic

○ Malignant polyp:

• muscularis mucosa involved.
• invasive, can give metastasis.

Question 5

TNM classifications ?

Answer 5

• Primary Tumor (T)
.
• Regional Lymph Nodes (N)
.
• Distant Metastases (M)
.

Question 6

DUKES’ CLASSIFICATION FOR

COLON CANCER ?

Answer 6

• A: confined to the bowel wall.
• B: through the bowel wall but not involving the free peritoneal serosal surface.
• C: lymph nodes involved.
• D: advanced local disease or metastases to the liver.

Question 7

SYMPTOMS OF COLORECTAL CANCER ?

Answer 7

• Occult blood in stool.
• Abdominal pain.
• Change in bowel habits.
• Rectal bleeding.
• Weight loss.
• Anemia.
• Palpable mass.
• Abdominal distention.
• Lack of apetite.
• Bowel obstruction.
• Metastatic disease: jaundice, ascites, hepatomegaly; other symptoms and signs from rarer sites of metastasis

Question 8

Typical locations of colon cancers ?

Answer 8

• Rectum 30%-50%.
• Sigmoid 15-20%.
• Descending c. 5%.
• Transverse c. 10%.
• Caecum and ascending colon 15%.

Question 9

CARCINOMA OF THE LEFT SIDE OF THE COLON
 ?

Answer 9

• MOST TUMOURS OCCUR IN THIS LOCATION. THEY ARE USUALLY OF THE STENOSING VARIETY.

Question 10

Signs and symptoms of CARCINOMA OF THE LEFT SIDE OF THE COLON ?

Answer 10

• Rectal bleeding.
• Alteration in bowel habit.
• Tenesmus.
• Obstruction.
• In addition to symptoms of intestinal obstruction, a sigmoid cancer may give rise to a feeling of the need for evacuation, which may result in tenesmus accompanied by the passage of mucus and blood..

Question 11

CARCINOMA OF THE TRANSVERSE

COLON ?

Answer 11

• Anaemia and lassitude

Question 12

CARCINOMA OF THE CAECUM

AND ASCENDING COLON ?

Answer 12

• Anaemia, severe and unyielding to treatment.
• The presence of a mass in the right iliac fossa.
• A carcinoma of the caecum can be the apex of an intussusception, presenting with the symptoms of intermittent obstruction.

Question 13

LAB TEST ABNORMALITIES of clonic cancer?

Answer 13

• Microcytic hypochromic anemia.
• CEA elevated.
• Fecal occult blood test(FOBT) positive.

Question 14

METHODS OF INVESTIGATION OF

COLON CANCER ?

Answer 14

• Endoscopy.
• Ultrasonography (liver metastases).
• Abdominal CT.
• Chest X-ray or chest CT.
• EUS, MRI (evaluation of local tumour invasion).

Question 15

OPERATIONS in caecum or ascending colon cancer ?

Answer 15

• Carcinoma of the caecum or ascending colon is treated when resectable by right hemicolectomy. When the hepatic flexure is involved, the resection must be extended correspondingly.

Question 16

OPERATIONS:

In the carcinoma of the transverse colon ?

Answer 16

• when there is no obstruction, excision of the transverse colon and the two flexures together with the transverse mesocolon and the greater omentum, followed by end-to-end anastomosis, can be used. An alternative is an extended right hemicolectomy.

Question 17

OPERATIONS:

Carcinoma of the splenic flexure ?

Answer 17

Carcinoma of the splenic flexure- extended left hemicolectomy. Descending colon – left hemicolectomy.

Question 18

OPERATIONS:

Carcinoma of the sigmoid colon ?

Answer 18

Sigmoidectomy.

Question 19

OPERATIONS:

Carcinoma of the rectum ?

Answer 19

low anterior resection, abdominoperineal resection.

Question 20

WHEN A GROWTH IS FOUND TO BE

INOPERABLE ? Upper part of the left colon ?

Answer 20

• Upper part of the left colon, a colostomy is performed.

Question 21

WHEN A GROWTH IS FOUND TO BE

INOPERABLE ? Pelvic colon?

Answer 21

• Pelvic colon - a left iliac fossa colostomy is preferable.

Question 22

WHEN A GROWTH IS FOUND TO BE
INOPERABLE ?
ascending colon ?

Answer 22

• Inoperable growth in the ascending colon - a bypass using an ileocolic anastomosis is the best procedure.

Question 23

WHEN A GROWTH IS FOUND TO BE

INOPERABLE ? multiple tumours ?

Answer 23

• A total colectomy needs to be considered for multiple tumours.
• over 95% of colonic carcinomas can be resected.

Question 24

HEPATIC METASTASES ?

Answer 24

• 30% 5-year survival following hepatectomy for colorectal cancer metastases.
• Irresectable symptomatic hepatic metastases may be suitable for other treatments including cytotoxic drugs or ablative treatments.

Question 25

neoadjuvant radiotherapy ?

Answer 25

• rectal cancer up to 8-10cm,
• r.c. T3-4, Nx-0, M0 or all T, N1-2, M0
• localy advanced and nonresectable rectal cancer

Question 26

ADJUVANT THERAPY ?

Answer 26

• Chemotherapy. (in stage III and IV TNM).
• Radiotherapy.
• Paliative chemo- and/or radiotherapy.