COLORECTAL MALIGNANCIES

Divina B. Esteban, M.D., FPSMO

Rizal Medical Center

Epidemiology:

• Worldwide incidence varies from:

3.4/100,000 - Nigeria

to

35.8/100,000 - Connecticut, USA

Philippine data: 1993-1997*

• Colon Cancer:– 5th most common (males) - 11.5/100,000

– 7th among females (9.5/100,000)

– 6th for both sexes (10.4/100,000)

– ASR in Filipino migrants to USA > ASR in the Philippines

– Intermediate incidence between Thailand & high rates in Asia, USA & Europe

*Cancer In The Phil. Volume III. 2002

Philippine data 1993-1997*• Rectal cancer

– 9th most common (M) - 7.9/100,000

– 11th most common (F) - 5.7/100,000

– 11th for both sexes - 6.7/100,000

– ASR in Filipino migrants > than those observed in the Philippines

– Int. inc. bet. low rates in Thailand and high rates in Asia, Europe & USA

*Cancer In The Philippines Vol.. III. 2002

Leading cancer sites, Males , 1993-1997DOH-Rizal and PCS - Manila Cancer Registries

0 10 20 30 40 50 60

Nasopharynx

Leukemias

Lymphoma

Rectum

Stomach

Colon

Prostate

Liver

Lung 5431

2624

1590

1257

993

910

956

1276

1276

ASR/100,000

51.5

20.9

19.3

11.5

7.8

9.2

6.6

6.0

6.0

663Oral Cavity 5.7

Leading Cancer Sites , Females, 1993-1997DOH - Rizal & PCS - Manila Cancer Registries

0 10 20 30 40 50 60

Leukemias

Stomach

Rectum

Liver

Thyroid

Colon

Ovary

Lung

Cervix

Breast

ASR/100,000

7929

1813

725

1115

3378

1934

925

1244

1639

802

48.0

19.0

11.0

9.3

8.5

5.7

5.3

5.2

13.8

6.7

2005 Estimates*

• 8585 new colorectal cancer cases

Males: 4737 Females: 3848

• 5558 deaths from colorectal cancer Males: 3064 Females: 2494

*2005 Philippine Cancer Facts & Estimates. PCSI. 2004

Females: 3

Philippine Survival Data*

• Colon Cancer Overall median survival: 49 months 5-year survival rate: 47.72% 10-year survival rate: 32.38%

• Rectal Cancer Overall median survival: 24 months 5-year survival rate: 19.45% 10-year survival rate: 5.84%

*Mapua et al, Population-based Cancer Survival, PCS-MCR.

RISK FACTORS

• Familial adenomatous polyposis (FAP)

• Adenomatous polyps in colon/ rectum

• Chronic ulcerative colitis

• Familial cancer syndrome

• Family history

• High -meat and high fat/ low fiber diet

SCREENING Guidelines

• Screening for >50 years old: – Annual FOBT– Flexible sigmoidoscopy or DCBE every 5 yrs

• Screening for 1st degree relative w/ cancer– Flexible sigmoidoscopy, DCBE or colonoscopy every 5-10 years from age

50 years– If relative was Dx before age 55, colonoscopy should be done at age 50 or

10 years prior to index case

• Screening for (+) hx of adenoma or CA• Screening for (+) ulcerative colitis• Screening for HNPCC and FAP

SCREENING Guidelines cont.

• Screening for pts with (+) hx of adenoma or CA :– Colonoscopy, DCBE or flexible sigmoidoscopy

every 3-5 years– Repeat colonoscopy within 1 yr if fragmented

polyp > 1 cm, high gr dysplasia, villous changes; multiple > 2; (+) FH; more than 60 yrs old

– Flexible sigmoidoscopy or DCBE every 5 yrs

SCREENING Guidelines cont.• Screening for pts. with ulcerative colitis

If more than 8 yrs duration: FOBT every 2 yrs– Flexible sigmoidoscopy every 5 yrs from age 50 years

• Screening for HNPCC and FAP– Genetic consult– Annual colonoscopy from age 25 years

SCREENING Guidelines

• for high risk groups & symptomatic patients:– Colon Cancer:

• Fecal blood tests

• Colonoscoopy +/- biopsy

• Barium enema

– Rectal Cancer• Digital rectal examination

• Proctosigmoidoscopy

Clinical Presentation

• Colon Cancer - Right-sided Lesion : (bulky, exophytic, large diameter, more fluid

content)

• Abdominal pain• Diarrhea• Occult gastrointestinal bleeding - anemia• Weight loss• Signs of low small bowel obstruction• Mass in the right iliac fossa

Clinical Presentation

• Colon Cancer - Left-sided Lesion: (annular or infiltrating, small diameter, semi-solid

to solid contents)

• Obstruction• Bleeding or bloody stools• Perforated pericolic abscesses or peritonitis• Change in bowel habits• Abdominal discomfort

Clinical Presentation

• Rectal Cancer:

• Rectal bleeding (bright red)• Change in bowel habits

• constipation / diarrhea

• Feeling of incomplete emptying after BM ; unproductive urge to defecate; tenesmus

• Persistent narrowing of stools• Rectal mass• Unexplained weight loss

Diagnosis

• Careful history (unexplained weight loss, anemia, change in bowel habits, abdominal pain, constipation, etc)

• Physical examination including digital rectal examination (DRE)

• Colonoscopy, proctosigmoidoscopy +/- bx• Barium enema• Tumor markers : CEA

PATHOLOGY

Histological Classification

1. Epithelial Tumors• Adenocarcinoma• Mucinous Adenocarcinoma• Signet-ring cell carcinoma• Squamous cell carcinoma• Adenosquamous carcinoma• Small cell carcinoma• Undifferentiated carcinoma

• Histological Classification (cont)

2. Carcinoid Tumors

3. Non-epithelial tumors (Leiomyosarcoma)

4. Hematopoietic & Lymphoid Neoplasms

5. Unclassified Tumors

TNM STAGING

Primary Tumor (T)

T0 No evidence of primary tumor Tis CIS :inv of lamina propria or muscularis mucosa T1 Tumor invades the submucosa T2 Tumor invades the muscularis propria T3 Tumor invades thru m. propria into subserosa/to

nonperitonealized pericolic or perirectal tissues

T4 Tumor directly inv. other organs/perforates the visceral peritoneum

TNM STAGING (cont.)

Regional Lymph nodes (N)

Nx Regional LN cannot be assessed N0 No regional LN metastasis N1 Metastasis to 1-3 regional LN N2 Metastasis in 4 or more pericolic LN N3 Metastasis in any LN along the course of a named vascular trunk &/or mets. to apical node(s)

TNM STAGING (cont.)

Distant Metastasis (M)

Mx distant metastasis cannot be assessed

M0 No distant metastasis

M1 Distant metastasis

TNM STAGING (cont.)

Stage Groupings: TNM Astler-Coller modified 0 Tis N0 M0 n/a

I T1 N0 M0 Stage A T2 N0 M0 Stage B1

II T3 N0 M0 Stage B2 T4 N0 M0 Stage B3

III Any T N1 M0 Stage C1- C3 Any T N2 M0

IV Any T Any N M1 Stage D

PROGNOSTIC FACTORS:

1 Disease extension beyond the rectal wall– for (+)LN but tumor confined to wall

(Tis-2 N1-3), loc. recurrence = 20-40%– for (-) LN but w/ extension beyond wall (T3 or T4A N0 or T4B N0),

loc. recur. = 20-35% – for (+) LN & (+) ext. beyond wall (T4N1-3, T4b N1-3), loc. recur. =

40- 65%

–

• Nodal involvement

PROGNOSTIC FACTORS

PROGNOSTIC FACTORS cont.

2 Lymph node involvement

3 Extrarectal extension

= Amount of uninvolved tissue (circumferential or radial margins)

Define the extraluminal extent of tumors

Measure the narrowest radial margin

Prognostic Factors cont.

• Histologic grade• Stage of tumor• Depth of invasion• Frequency of nodal involvement• Number of lymph nodes involved• Bowel obstruction 2o to tumor• Tumor perforation

PATTERNS OF FAILUREafter a curative resection

• Local recurrence– 30-50% in MAC B3, C2 and C3 lesions– 15-20% in many B2 and most C1 lesions

• Peritoneal seedings - Least common in rectal primaries

• Systemic metastasis– Rectal Cancer: Liver and Lung due to venous

drainage– Colon CA: Initial mets in the liver (venous

drainage via the portal system)

TREATMENT SCHEMA

• Colon Cancer Suspect

• Rectal Cancer Suspect