1. Malignant Rectal Polyp
Joint Hospital Surgical Grand Round 18 Apr 2009
Malignant Rectal Polyp
Dr Kit-wai Lai
Department of Surgery
Tuen Mun Hospital

2. Malignant Rectal Polyp
Polyps with cancer cells penetrating the muscularis mucosa
Invasion limited to submucosa
i.e. T1 lesion

3. Size the most important factor determining risk of malignant transformation within a polyp
Tytherleigh et al. BJS 2008;95:
>1cm %
>42mm %

4. Haggitt Classification
Level 0: noninvasive (severe dysplasia)
Level 1: invading through the muscularis mucosa but limited to the head of a pedunculated polyp
Level 2: invading the neck of a pedunculated polyp
Level 3: invading the stalk of a pedunculated polyp
Level 4: invading into the submucosa below the stalk of a pedunculated polyp
( Sessile malignant polyplevel 4 )
All sessile polyps with invasive cancer are level 4

5. Kikuchi Classification of Adenocarcinoma in Sessile Polyp
Haggitt level 1,2,3 = Kikuchi Sm1
level = Sm1, Sm2 or Sm3

6.  Local Therapy Opportunity of cure with less detriment
Staging is critical to management
Histological Assessment
Most important factor to predict risk of lymphatic spread
 Local Therapy Opportunity of cure with less detriment
Tytherleigh et al. BJS 2008;95:

7. Histopathological Features
Low-risk ERC
High-risk ERC
Depth of wall invasion
Haggitt 1-3
Kikuchi Sm1 & (possibly Sm2)
Kikuchi Sm3 & (possibly Sm2)
Grade
Well Moderate differentiated
Poorly differentiated
Undifferentiated
Lymphovascular invasion - +
Best estimate of the probability of regional LN metastasis
Bretagnol et al. Dis Colon Rectum 2007;50:
Rate of lymph node metastasis
Sm % Sm2 8% Sm3 23%
Nascimbeni et al. Dis Colon Rectum 2002;45:
Poorly differentiated %
Goldstein et al. Am J Clin Pathol 1999;111:51-8
Depth: best estimate of the probability of regional LN metastasis
Grade of initial bx may be diff from excised specimen
Moderate 20%
*Risk of LN metastasis vs sm1/2/3: Nascimbeni, Kikuchi
*Nascimbeni et al. [15] studied histological specimens retrospectively from 353 patients undergoing colorectal resection for sessile T1 lesions.( )
The authors reported that the depth of invasion into the lower third of the submucosa (classified as ‘sm3’), the presence of lymphovascular invasion, and lesions in the
lower third of the rectum were significant predictors of lymph node metastasis
*(St Marks) S. Rasheed et al. Colorectal Disease, 10, 231–237. ( )total 313 T1 in 55 (18.2%) and T2 in 248 (81.2%). The node positive group did however contain a significantly higher number of patients with poorly differentiated tumours (P = 0.001) and patients with evidence of extramural vascular invasion (P = 0.002). Finally there was no significant difference in the number of patients with sm1, sm2, sm3(12-14%), or T2 (~19%)
tumour depths within the lymph node positive and negative groups
Limitation: small sample size of T1, retrospective, surgeon choose for radical excision rather than local excision

8. Clinical Scenario 1. Post Colonoscopic polypectomy of rectal polyp
Colonoscopy: 2.5cm rectal polyp (3cm from anal verge)
Biopsy: adenocarcinoma 2.
Post Colonoscopic polypectomy of rectal polyp
Pathology: adenocarcinoma arise from tubular adenoma

9. Clinical Scenario 1.
Colonoscopy: 2.5cm rectal polyp (3cm from anal verge)
Biopsy: adenocarcinoma

10. Scenario 1 2.5cm rectal Polyp
Digital rectal exam
ERUS MRI CT
LN +
LN -
Radical Sx
AR/TME/APR T2 T1
Local Excision
+ Adj ChemoRT
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
No High Risks Features
Follow-up
Recurrence
No Recurrence
Salvage Surgery
APR for an ERC should be unusual as there are many sphincter-preserving techniques that can be empolyed
Pt’s choice, co-morbidity, body habitus will also affect tx decision
Local excision + adj chemoRT for T2 and high risk T1: assuming that further surgery is not an option

11. ERUS Best method to determining T stage T stage N stage Accuracy: 90 %
Sensitivity : 85%
Specificity: 95%
N stage
Accuracy: 80%
Sensitivity: 70%
Specificity: 80%
hypoechoic nodes with short axis diameters of 5 mm
or more, nodes of any diameter with heterogeneous echogenicity,
or hypoechoic nodes of any diameter in cases with biopsy-proven
Bretagnol et al. Dis Colon Rectum 2007;50:

12. ERUS T1-slight (Sm1) detection
Sensitivity (99%) Specificity (74%) Accuracy (96%)
Akasu et al. World J Surg 2000;24:
May assess residual tumour following polypectomy
Follow up after local excision or radical surgery
Hernandez De Anda et al. Dis Colon Rectum 2004; 47: 818–824
Limitations
Sm1
Operator dependent
Tumor height
Tumour stenosis
Peritumoral fibrosis and inflammatory tissue
Effect of pre op radiotherapy or haemorrhage in bowel wall after bx
Sensitivity/specificity/overall accuracy rates for detection of slight submucosal invasion, massive
submucosal invasion, and muscularis propria invasion were 99%/
74%/96%, 98%/88%/97%, and 97%/93%/96%, respectively
Limitations: peritumoral fibrosis and inflammatory tissue, operator dependent, tumor height, tumour stenosis, effect of pre op radiotherapy or haemorrhage in bowel wall after bx
-the substitution of the typical five-layer structure of the rectal wall by a mixed echoic pattern involving a segment of the rectal wall. The staples after an anastomosis
are usually visualized as a circumferential line of small, bright echoes without a shadow. Local recurrence often appears as a well-defined hypoechoic homogenous mass involving the rectal wall or as a hypoechoic extrarectal node, persisting in at least two consecutive exams (Figs. 1 and 2). Recurrence was confirmed by endoscopic biopsy, ultrasound-guided biopsy, or CT scan-guided biopsy.
Sm2

13. MRI Overall T stage accuracy 59-95% T1,2 lesion (vs ERUS) N stage
Similar sensitivities
Lower specificity (69%)
N stage
Comparable vs ERUS
Endorectal and phased-array coils--> better resolution and accuracy for predicting tumour stage
New techniques accuracy ~ 90%
A meta analysis: T1, 2 lesion: ERUS, MRI smilar sensitivities, ERUS 86% specificity sig higher MRI69%
Bretagnol et al. Dis Colon Rectum 2007;50:

14. Scenario 1 2.5cm rectal Polyp
Digital rectal exam
ERUS MRI CT
LN -
LN + T1 T2
Local Excision
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
No High Risks Features
APR for an ERC should be unusual as there are many sphincter-preserving techniques that can be empolyed
Pt’s choice, co-morbidity, body habitus will also affect tx decision
Local excision + adj chemoRT for T2 and high risk T1: assuming that further surgery is not an option
Follow-up
Local Excision
+ Adj ChemoRT
Radical Sx
AR/TME/APR
Recurrence
No Recurrence
Salvage Surgery

15. Local Excision Potential advantage Sphincter preservation
Minimal mortality and morbidity
Low urinary/sexual dysfunction risk

16. Local Excision Parks’ Per Anal Excision
Lesions 6-10cm from anal verge
Aid of anal retractors
Full thickness excision
Transanal Endoscopic Microsurgery
Resectoscope
Usual below peritoneal reflection
Snare polypectomy or endoscopic mucosal resection is used to treat polyps that are thought to be benign.
A polyp that does not ‘lift’ on submucosal infiltration should be regarded as malignant
???peritoneal reflection

17. Local Excision LR
Bretagnol et al. Dis Colon Rectum 2007;50:

18. Local Excision vs Radical Sx
T1sm3 lesion
Radical Surgery had lower rates of distant metastasis and better survival
Bretagnol et al. Dis Colon Rectum 2007;50:
NASCIMBENI ET AL Dis Colon Rectum 2004; 47: 1773–1779
We compared 70 patients who underwent local excision with 74 patients who underwent oncologic resection. Among patients with lesions in the middle or lower third of the rectum, 1) the five-year and ten-year outcomes were significantly better for overall survival and cancer-free survival in the oncologic resection group, but there were no significant differences in local recurrence or distant metastasis; 2) the multivariate risk factors for long-term, cancer-free survival were invasion into the lower third of the submucosa, local excision, and older than aged 68 years; and 3) for lesions with invasion into the lower third of the submucosa, the oncologic resection group had lower rates of distant metastasis and better survival. Among patients with lesions
in the lower third of the rectum, 1) the five-year and tenyear outcomes showed no significant differences in survival, local recurrence, or distant metastasis between the two groups; and 2) for lesions with invasion into the lower third of the submucosa, the oncologic resection group showed a trend of improved survival, which was not statistically significant, possibly because of low statistical power from the small sample size

19. Scenario 1 2.5cm rectal Polyp
Digital rectal exam
ERUS MRI CT
LN -
LN + T1 T2
Local Excision
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
No High Risks Features
APR for an ERC should be unusual as there are many sphincter-preserving techniques that can be empolyed
Pt’s choice, co-morbidity, body habitus will also affect tx decision
Local excision + adj chemoRT for T2 and high risk T1: assuming that further surgery is not an option
Follow-up
Local Excision
+ Adj ChemoRT
Radical Sx
AR/TME/APR
Recurrence
No Recurrence
Salvage Surgery

20. Adjuvant chemoradiotherapy
Limited data
May be helpful
If further surgery is not an option
T1 lesions with adverse pathologic features
T2 lesions
(Tytherleigh et al. BJS 2008;95: )
Difficult to interpret
Most retrospective studies
Lack of controlled data
Adjuvant regime not always based on a defined protocol
Difficult to interpret
Most series retrospective studies with heterogeneous gp of pt n lack of controlled data
adjuvant regime is not always based on a defined protocol
In conclusion, the limited data suggest that adjuvant
chemoradiotherapy may be helpful in patients
with T1 lesions with adverse pathologic features and
T2 lesions, achieving a local recurrence rate < 20
percent.
Bretagnol et al. Dis Colon Rectum 2007;50:

21. Scenario 1 2.5cm rectal Polyp
Digital rectal exam
ERUS MRI CT
LN -
LN + T1 T2
Local Excision
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
No High Risks Features
APR for an ERC should be unusual as there are many sphincter-preserving techniques that can be empolyed
Pt’s choice, co-morbidity, body habitus will also affect tx decision
Local excision + adj chemoRT for T2 and high risk T1: assuming that further surgery is not an option
Follow-up
Local Excision
+ Adj ChemoRT
Radical Sx
AR/TME/APR
Recurrence
No Recurrence
Salvage Surgery

22. Follow up Regular endoscopic surveillance of rectum and scar
Digital rectal exam + Endoscopy + CEA
First 2 years: every 3 months
Next 3 years: every 6 months
Then annually
National comprehensive Cancer Network guidelines recommended for T1 with local excision
Q3m x 2yr
Q6m x 3 yr
q1y
Mellgren et al. Dis Colon Rectum 2000; 43: 1064–1071
NCCN guideline

23. Follow up ERUS Advisable Frequency: subject to debate One study showed
More isolated local recurrence in the follow-up ERUS group underwent Salvage Surgery (44% vs 23 %), but the differences were not significant
Hernandez De Anda et al. Dis Colon Rectum 2004; 47: 818–824
ERUS every four months for the first three years and every six
months for the two years after curative surgery

24. Scenario 1 2.5cm rectal Polyp
Digital rectal exam
ERUS MRI CT
LN -
LN + T1 T2
Local Excision
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
No High Risks Features
APR for an ERC should be unusual as there are many sphincter-preserving techniques that can be empolyed
Pt’s choice, co-morbidity, body habitus will also affect tx decision
Local excision + adj chemoRT for T2 and high risk T1: assuming that further surgery is not an option
Follow-up
Local Excision
+ Adj ChemoRT
Radical Sx
AR/TME/APR
Recurrence
No Recurrence
Salvage Surgery

25. Recurrence Long-term FU beyond 10 years is necessary
Unresected disease in regional lymphatics cause local failure
Diagnose early for salvage surgery
Tytherleigh et al. BJS 2008;95:

26. Salvage Surgery
56-100% of patients with recurrence suitable for salvage surgery
Results controversial
May not afford same outcomes as initial classical treatment
Decreased survival if resection is delayed at time of recurrence
(for adverse pathology of local excision specimen)
Disease free survival rates 20-35%
Mellgren et al. Dis Colon Rectum 2000; 43: 1064–1071

27. Clinical Scenario 2. Colonoscopic polypectomy of rectal polyp
Pathology: adenocarcinoma arise from tubular adenoma

28. Scenario 2 Post polypectomy (Adenoca arise from TA)
No High Risks Features
Haggitt level 1,2,3
Kikuchi Sm1
High Risks Features
Sm3 (Sm2)
Grade
lymphovascular
ERUS MRI CT
LN-
LN+
Margin involvement
Yes
Histological assessment not adequate No
Local Excision No
Yes
Follow up
Radical Surgery
High Risks Features

29. Summary
Staging and
Adequate Histological Assessment is crucial in management of malignant rectal polyp

30. Summary Local excision Radical Surgery Recurrence
Recommended for low risk T1 sm1 lesion
Adjuvant therapy considered in high risk T1, T2 if surgery not an option
Radical Surgery
Recommended for high risk T1 , T2 lesion
Recurrence
Diagnose early for salvage surgery

31. Thank You