This document discusses carcinoma of the rectum. It begins by explaining the anatomy of the rectum and its blood supply, lymphatic drainage and innervation. It then discusses the epidemiology, risk factors, staging systems including Dukes and TNM classification. Signs and symptoms, diagnostic workup including endoscopic, radiological and biopsy evaluation are explained. Principles of surgical treatment including resection margins are outlined. The goal of surgery is eradication of the primary tumor along with adjacent mesorectal tissue.

1. Carcinoma Rectum
By
Dr SYED UBAID

2. why is rectal carcinoma different
• Anatomy
• Relations
• Mesorectum
• Lateral nodal spread .

3. Epidemiology
• Colorectal caner is the third most frequently diagnosed
cancer in the US men and women.
• Incidence rate in India is quite low about 2 to 8 per
100,000
• Median age- 7th decade but can occur any time in
adulthood
• Lifetime risk
1 in 10 for men
1 in 14 for women

4. Incidence in Large Bowel
• Cecum 14 %
• Ascending colon 10 %
• Transverse colon 12 %
• Descending colon 7 %
• Sigmoid colon 25 %
• Rectosigmoid junct 0.9 %
• Rectum 23 %

5. ANATOMY
• 15cm
• Starts - 3rd sacral vertebra
• Ends 2-3cm infront of the coccyx
• The rectum is “fixed” posteriorly and laterally by Waldeyer’s
fascia
• anteriorly : Denonvilliers’ fascia
Reference: NCCN guidelines on colorectal carcinoma,
Fishers mastery of surgery 6th edition,Maingots abdominal operations 12th edition

6. Clinical Anatomy
• Begins at 12-15 cm
from anal verge.
• Diameter
 4 cm (upper part)
 Dilated (lower
part)
• Posterior part of the
lesser pelvis and in
front of lower three
pieces of sacrum and
the coccyx
• Begins at the
rectosigmoid junction,
at level of third sacral
vertebra

7. Clinical Anatomy
.
• Ends at the anorectal
junction, 2-3 cm in front of
and a little below the coccyx
• Taenia of the sigmoid colon
form a continuous outer
longitudinal layer of smooth
muscle
• Fatty omental appendices are
discontinued

8. Rectum is divided into 3
portions
 3 distinct intraluminal
curves ( Valves of
Houston)
Lower rectum : 3 – 6 cm from
the anal verge
Mid rectum: 6 cm to 8 -10cm
from anal verge
 Upper rectum: 8 cm to
12 -15cm from anal verge

9.  Superior 1/3rd of the rectum
 Covered by peritoneum on
the anterior and lateral
surfaces
 Middle 1/3rd of the rectum
 Covered by peritoneum on
the anterior surface
 Inferior 1/3rd of the rectum
 Devoid of peritoneum
 Close proximity to adjacent
structure including boney
pelvis.
Peritoneal Relations

10. Arterial Supply
• Superior rectal A –
from IMA; supplies
upper and middle
rectum
• Middle rectal A- from
Internal iliac A.
(supplies lower
rectum)
• Inferior rectal A- from
Internal pudendal A.

11. Venous Drainage
Superior rectal V- upper
& middle third rectum
Middle rectal V- lower
rectum and upper anal
canal
Inferior rectal vein-
lower anal canal

12. Nerve supply
• Sympathetic , L1–L3
• sacral (parasympathetic), s2-s4
• inferior hypogastric nerves
innervate - rectum, bladder, ureter, prostate,
seminal vesicles, membranous urethra, corpora
cavernosa.
• injury- impotence, bladder dysfunction, and
loss of normal defecatory mechanisms.

13. Reference: Sato K, Sato T. The vascular and neuronal composition of the lateral ligament of the
rectum and the rectosacral fascia. Surg Radiol Anat. 1991;13:17–22.

14. Lymphatic drainage
• upper and middle rectum - inferior
mesenteric nodes
• lower rectum - inferior mesenteric system
• posteriorly - middle sacral artery
• anteriorly - retrovesical or rectovaginal
septum
iliac nodes periaortic nodes.

15. Lymphatic drainage
 Upper and middle rectum
 Pararectal lymph nodes,
located directly on the
muscle layer of the rectum
 Inferior mesenteric lymph
nodes, via the nodes along
the superior rectal vessels
 Lower rectum
 Sacral group of lymph nodes
or Internal iliac lymph nodes
 NODAL GROUPS
Perirectal Internal iliac
Common iliac Paraortic

16. Lymphatic Drainage

17. Aetiology
 Etiological agents
 Environmental & dietary factors
 Chemical carcinogenesis.
 Associated risk factors
 Male sex
 Family history of colorectal cancer
 Personal history of colorectal cancer, ovary,
endometrial, breast
 Excessive BMI
 Processed meat intake
 Excessive alcohol intake
 Low folate consumption
 Neoplastic polyps.
 Hereditary Conditions (FAP, HNPCC)

18. Adenoma to carcinoma sequence
• First described by DUKES in 1926
• The time course is 5-10 years
• Non inherited cases has ras, p53 mutations
• Malignant potential –
villous adenoma
Diameter >2cm

19. .

20. CLINICAL
PRESENTATIONS

21. Symptoms
 Asymptomatic
 Blood PR(60%)
 Change in bowel habit(43%) (diarrhoea, constipation,
narrow stool, incomplete evacuation, tenesmus)
 Occult bleeding(23%)
 Abdominal discomfort (20%)(pain, fullness, cramps,
bloating, vomiting)
 Weight loss, tiredness
 Back Pain
 Urinary symptoms
 Pelvic pain(5%) indicating nerve trunk involvement

22. Acute Presentations
• Intestinal obstruction
• Perforation
• Massive bleeding

23. Signs
• Pallor
• Abdominal mass
• PR mass
• Jaundice
• Nodular liver
• Ascites
 Rectal metastasis travel along portal drainage to liver via
superior rectal vein as well as systemic drainage to lung
via middle inferior rectal veins.

24. Signs
 Signs of primary cancer
 Abdominal tenderness and distension – large bowel obstruction
 Intra-abdominal mass
Digital rectal examination – most are in the lowest
12cm & reached by examining finger
 Rigid sigmoidoscope
 Signs of metastasis and complications
 Signs of anaemia
 Hepatomegaly (mets)
 Monophonic wheeze
 Bone pain

25. WHO Classification of
Rectal Carcinoma
• Adenocarcinoma in situ / severe dysplasia
• Adenocarcinoma
• Mucinous (colloid) adenocarcinoma (>50% mucinous)
• Signet ring cell carcinoma (>50% signet ring cells)
• Squamous cell (epidermoid) carcinoma
• Adenosquamous carcinoma
• Small-cell (oat cell) carcinoma
• Medullary carcinoma
• Undifferentiated Carcinoma

26. Dukes classification
 Dukes A: Invasion into but not through the
bowel wall
 Dukes B: Invasion through the bowel wall but
not involving lymph nodes
 Dukes C: Involvement of lymph nodes
 Dukes D: Widespread metastases

27. Modified astler coller
classification-
 Stage A : Limited to mucosa
 Stage B1 : Extending into muscularis propria
but not penetrating through it; nodes not involved
 Stage B2 : Penetrating through muscularis
propria; nodes not involved
 Stage C1 : Extending into muscularis propria but
not penetrating through it. Nodes involved
 Stage C2 : Penetrating through muscularis
propria. Nodes involved
 Stage D: Distant metastatic spread

28. Tis T1 T2 T3 T4
Extension to an adjacent organ
Mucosa
Muscularis mucosae
Submucosa
Muscularis propria
Subserosa
Serosa
TNM ClassificationTX Primary tumor cannot be assessed
T0 No evidence of primary tumor
Tis Carcinoma in situ: intraepithelial or invasion of lamina propria
T1 Tumor invades submucosa
T2 Tumor invades muscularis propria
T3 Tumor invades through the muscularis propria into pericolorectal tissues
T4a Tumor penetrates to the surface of the visceral peritoneum
T4b Tumor directly invades or is adherent to other organs or structures

29. TNM Classification

30. Stage grouping
Stage T N M Dukes MAC
0 Tis N0 M0 - -
I T1 N0 M0 A A
T2 N0 M0 A B1
IIA T3 N0 M0 B B2
IIB T4 N0 M0 B B3
IIIA T1-2 N1 M0 C C1
IIIB T3-4 N1 M0 C C2/C3
IIIC Any T N2 M0 C C1/C2/C3
IV Any T Any
N
M1 - D

31. Stage 0 Rectal Cancer
• Known as “cancer in
situ,” meaning cancer
is located in the
mucosa.

32. Stage I Rectal Cancer
• The cancer has grown
through the mucosa
and invaded the
muscularis (muscular
coat)

33. Stage II Rectal Cancer
• The cancer has grown
beyond the muscularis
of the colon or rectum
but has not spread to
lymph nodes

34. Stage III Rectal Cancer
• Cancer has spread to
the regional lymph
nodes (lymph nodes
near the colon and
rectum)

35. Stage IV Rectal Cancer
• Cancer has spread
outside of colon or
rectum to other
areas of the body

36. Prognostic factors
 Good prognostic
factors
 Old age
 Gender(F>M)
 Asymptomatic pts
 Polypoidal lesions
 Diploid
 Poor prognostic
factors
 Obstruction
 Perforation
 Ulcerative lesion
 Adjacent structures
involvement
 Positive margins
 LVSI
 Signet cell carcinoma
 High CEA
 Tethered and fixed
cancer

37. Diagnostic Workup
• History—including family history of colorectal cancer
or polyps
• Physical examinations including DRE and complete
pelvic examination in women: size, location, ulceration,
mobile vs. tethered vs. fixed, distance from anal verge
and sphincter functions.
• Proctoscopy—including assessment of mobility,
minimum diameter of the lumen, and distance from the
anal verge
• Biopsy of the primary tumor

38. Diagnostic Evaluation
• General
Clinical features.
• Lab. Studies
Complete blood cell count
Blood chemistry profile
CEA
• Evaluation
• Determination of Occult Blood
Digital Rectal Examination
Proctosigmoidoscopy
Flexible Fibreoptic Sigmoidoscopy & Colonoscopy.
Barium Enema
• Urologic Evaluation
• Other Imaging studies
• CT, USG, MRI, Chest X-ray, FDG- PET scan, Endorectal
U/S.

39. Colonoscopy or barium
enema
Figure: Carcinoma of the rectum. Double-
contrast barium enema shows a long
segment of concentric luminal narrowing
(arrows) along the rectum with minimal
irregularity of the mucosal surface.
To evaluate remainder of large bowel to rule out
synchronous tumor or presence of polyp syndrome.

40. Transrectal Ultrasound
• Used for clinical staging.
• 80-95% accurate in tumor
staging
• 70-75% accurate in
mesorectal lymph node
staging
• Very good at demonstrating
layers of rectal wall
• Use is limited to lesion < 14
cm from anus, not
applicable for upper
rectum, for stenosing tumor
• Very useful in determining
extension of disease into
anal canal (imp to plan
sphincter preserving
surgery)
Figure.Endorectal ultrasound
of a T3 tumor of the rectum,
extension through the
muscularis propria, and into
perirectal fat.

41. EUS : Accuracy
EUS CT
Depth of infiltration T staging 91% 71%
N staging 87% 76%

42. CT Scan
• Part of routine workup of patients
• Useful in identifying enlarged pelvic lymph-nodes and
metastasis outside the pelvis than the extent or stage of
primary tumor
• Limited utility in small primary cancer
• Sensitivity 50-80%
• Specificity 30-80%

43. CT Scan
• Ability to detect pelvic and para-aortic
lymph nodes is higher than peri-rectal
lymph nodes(75% to 87% vs. 45%)
Accuracy
T stage
60-80%
Accuracy
N stage
60-75%
Liver met. 70-79%

44. Figure: Mucinous adenocarcinoma of the
rectum. CT scan shows a large
heterogeneous mass (M) with areas of
cystic components. Note marked luminal
narrowing of the rectum (arrow).
Figure: Rectal cancer with uterine
invasion. CT scan shows a large
heterogeneous rectal mass (M) with
compression and direct invasion into the
posterior wall of the uterus (U).

45. Magnetic Resonance
Imaging (MRI)
• Greater accuracy in defining extent of rectal cancer
extension and also location & stage of tumor
• Helpful in lateral extension of disease, critical in
predicting circumferential margin for surgical
excision.
• Different approaches (body coils, endorectal MRI &
phased array technique)

46. Figure: Mucinous adenocarcinoma of the
rectum. T2-weighted MRI shows high signal
intensity (arrowheads) of the cancer lesion
in right anterolateral side of the rectal wall.
Figure: Normal rectal and perirectal
anatomy on high-resolution T2-weighted
MRI. Rectal mucosa (M), submucosa
(SM), and muscularis propria (PM) are
well discriminated. Mesorectal fascia
appears as a thin, low-signal-intensity
structure (arrowheads) and fuses with the
remnant of urogenital septum making
Denonvilliers fascia (arrows).

47. PET with FDG
• Shows promise as the most
sensitive study for the detection of
metastatic disease in the liver and
elsewhere.
• Sensitivity of 97% and specificity of
76% in evaluating for recurrent
colorectal cancer.
cancer
rectum
prostate pubic bone
bladder
Small bowel

48. Aims of treatment
• Local control
• Long-term survival
• Restoration of bowel continuity and
Preservation of anal sphincter.
• Bladder and sexual function and maintenance or
improvement in QOL.
• Careful preoperative screening is crucial in
determination of the location of lesion and its
depth of invasion

49. Treatment
Surgery Chemotherapy Radiotherapy

50. Treatment Overview
• Sx mainstay of treatment.
• After curative resection the 5 year survival drops
from 80% in stage I to about 40% in stage III
disease.
• Local recurrence remains a major site of failure
ranging from 5% in few selected series to about
40% in most reports.

51. Principles of surgical
management
• Removal of primary tumor with adequate
margin.
• T/t of draining LN.
• Restoration of function
• “En bloc” resection if necessary

52. GOAL OF SURGERY
• PRIMARY GOAL IS ERADICATION OF PRIMARY
TUMOR ALONG WITH ADJACENT
MESORECTAL TISSUE AND SUPERIOR
HEMORRHOIDAL ARTERY PEDICLE

53. RESECTION MARGIN
• Traditional margin of 5cm
• NSABP demonstrated no difference in survival
or local recurrence in distal margin of 2, 2-2.9,
>3cm
• Therefore, 2cm distal margin Is now
acceptable considering the limitation of distal
intramural spread of 2cm below the
peritoneal reflection

54. RESECTION MARGIN
• Circumferential radial margin is more crucial
• Length of mesorectum removed beyond the
primary tumor is between 3 to 5 cm as tumor
implants have not been shown further than
4cm

55. LOCAL EXCISION
Tumors amenable to local excision
• T1N0 or T2N0 lesion
• <4cm in diameter
• <40% in circumference of lumen
• <10 cm from dentate line
• Well to moderately differentiated histology
• No evidence of lymphatic or vascular invasion
• Local control for advanced disease

56. Local excision
• For superficially invasive (T1) tumors with low
likelihood of LN metastases
• Total biopsy, with further T/t based on pathology
• Tumors within 8 to 10 cm of anal verge,
• Encompass less than 40% of circumference of bowel
wall,
• well or moderately well differentiated histology,
• No pathological evidence of venous or lymphatic vessel
invasion on biopsy
• With unfavorable pathology patient should undergo
total mesorectal excision with or without sphincter-
preservation:
Positive margin (or <2 mm), lymphovascular
invasion,
Poorly differentiated tumors, T2 lesion

57. LOCAL EXCISION
TECHNIQUES:
Transsphincteric excision
Transanal excision
Transcoccygeal excision
Transanal endoscopic microsurgery

58. LOCAL EXCISION
TRANSANAL EXCISION
• Tumors 6-8 cm from anal verge
• 1 cm circumferential margin
• Full thickness excision

59. LOCAL EXCISION
TRANSANAL EXCISION

60. LOCAL EXCISION
TRANSCOCCYGEAL EXCISION
• Popularized by KRASKE
• Useful for more proximally placed, posterior
lesions
• 1 cm circumferential margin
• Complication: fecal fistula ( 5 to 20%)

61. LOCAL EXCISION
TRANSCOCCYGEAL EXCISION

62. LOCAL EXCISION
• TRANSANAL ENOSCOPIC MICROSURGERY
• the procedure of choice for early mid to upper
rectal lesion
• Offers better visualization, complete intact
excision

63. LOCAL EXCISION

64. LAR
• For tumors in upper/mid rectum allows
preservation of anal sphincter
• Join colon to low rectum
• Permanent colostomy if tumor too low
w

65. LOW ANTERIOR RESECTION WITH TME
• local failures are most often due to inadequate surgical
clearance of radial margins.
• conventional resection violates the mesorectal
circumference during blunt dissection, leaving residual
mesorectum.
• TME involves precise dissection and removal of the entire
rectal mesentery as an intact unit.
• local recurrence with conventional surgery averages
approx. 25-30% vs. TME 4-7% by several groups (although
several series have higher recurrence)

66. mesorectum
• Mesentry surrounding the rectum
• Covered by the visceral layer of the endopelvic fascia
• Contains
perirectal fat
Draining lymph nodes
Superior rectal blood vessels
• Holy plane – loose areolar tissue separating the
visceral and parietal layers
• Parietal layer covers the superior hypogastric plexus
,hypogastric plexus and pelvic plexus.
Reference: Heald, RJ; et al. (1982). "The mesorectum in rectal cancer surgery-the clue
to pelvic recurrence?". Br J Surg (John Wiley & Sons, New Jersey) 69: 613–616.

67. Reference :Fishers mastery of surgery 6th edition

68. LOW ANTERIOR RESECTION WITH TME
PROCEDURE :
A. MOBILIZATION OF COLON
B. TRANSECTION
C. RECONSTRUCTION
Double stapling technique
• Diverting loop ileostomy
• Colonic pouch/ transverse coloplasty

69. LOW ANTERIOR RESECTION WITH TME

70. LOW ANTERIOR RESECTION WITH TME
Specific complications
• Impotence (10-28%)
• Retrograde ejaculations
• Urinary incontinence

71. LOW ANTERIOR RESECTION WITH TME
TME ALONE (%) TME+RT (%) TME +LND (%)
LOCAL
RECURRENCE
12.1 5.8 6.9
LATERAL PELVIC
RECURRENCE
2.7 0.8 2.2
PRESACRAL
RECURRENCE
3.2 3.7 0.6

72. ABDOMINOPERINEAL DISSECTION
Suitable for
• Cancers involving the sphincter apparatus
• Incontinent to feces
Very High morbidity (61%)
Mortality 0 to (6.3%)

73. Abdomino-perineal
resection
 For tumors of distal rectum(lower 1/3rd) with distal edge
up to 6 cm from anal verge
 Associated with permanent colostomy and high
incidence of sexual and genitourinary dysfunction

74. Procedure
• Through combined abdominal and perineal
incisions, the anus, rectum, and sigmoid
colon are removed en bloc.
• Also called Miles Resection
• The proximal end of the bowel is exteriorized
through a separate stab wound as a
colostomy.
• The distal end is pushed into the hollow of
the sacrum and removed via perineum
• Performed to treat cancer of the lower
rectum—and diseases are too low for use of
stapling devices

75. Heavy purse string suture
around anus to occlude it

76. Colon and Rectum are
delivered through the
perineal resection

78. Total mesorectal excision
• Local failures are most often due to inadequate surgical
clearance of radial margins.
• Conventional resection violates the mesorectal circumference
during blunt dissection, leaving residual mesorectum.
• Excision of fascia enveloping the fat pad around the rectum
• TME involves precise dissection and removal of the entire
rectal mesentery as an intact unit.
• Local recurrence with conventional surgery averages approx.
25-30% vs. TME 4-7% by several groups (although several
series have higher recurrence)

79. TOTAL MESORECTAL
EXCISION

80. Total Mesorectal
Excision

81. ABDOMINOPERINEAL DISSECTION
Complications:
• Perineal wound complications (25%)
• Urinary incontinence (as high as 50%)
• Sexual dysfunction (as high as 67%)
• Stoma complications
(ischemia, retraction, hernia, stenosis , prolapse)

82. ABDOMINOPERINEAL DISSECTION
En block excision :
• Posterior vaginectomy ( 1cm margin)
• prostatectomy
• Pelvic exenteration
( high morbidity and mortality )
Consider prophylactic bilateral oopherectomy

83. Pelvic Exenteration
The surgeon removes the rectum as well as nearby organs such as the
bladder, prostate, or uterus if the cancer has spread to these organs.
A colostomy is needed after this operation. If the bladder is removed,
a urostomy (opening to collect urine) is needed.
15cm
High Anterior Resection
Low Anterior Resection
Ultra-low Anterior Resection
Abdominoperineal Resection (APR)

84. CHEMORADIATION
ADVANTAGES OF NEOADJUVANT CHEMOTHERAPY
• Downstage the tumor (60-80%)
• Achieve complete pathological response (15-30%)
• To allow sphincter preserving procedures
• No radiation to anastomosis, small bowel in pelvis

85. CHEMORADIATION
• 1990 NIH consensus concluded the efficacy in
local control in stage II & III
• To lower local failure rates and improve survival
in resectable cancers
• to allow surgery in primarily inoperable cancers
• to facilitate a sphincter-preserving procedure
• to cure patients without surgery: very small
cancer or very high surgical risk

86.  5Fu
 Leucovorin
 Oxaliplatin
 Irinotecan
 Bevacizumab
 cetuximab
Combinations
 FOLFOX
 FOLFIRI
 Leucovorin/5FU
 Capecitabine
 Bevacizumab in
combination with the
above regimens.
Chemotherapy agents
CHEMORADIATION

87. Polish Trial
• Polish Study (Br J Surg. 2006): 316 patients with resectable T3-4 rectal
cancer, no sphincter involvement, tumor palpable on DRE (1999-2002).
Preop short Preop
course RT conventional
RT
5 y. OS 67.2% 66.2%
5 y. local relapse 9.0% 14.2%
DFS 58.4% 55.6%
NO difference in anorectal or sexual dysfunction

88. Dose limitations
• Small bowel- 45–50 Gy
• Femoral head and neck- 42 Gy
• Bladder -65 Gy
• Rectum- 60 Gy

89. CURRENT RECOMMENDATION
•Primary
surgery
•No adjuvant
therapy
Stage I

90. CURRENT RECOMMENDATION
• Neoadjuvant Chemoradiation
( 5-FU based chemotherapy
with radiotherapy )
• Rest for 4-8 weeks
• Total mesocolic excision
• Rest for 4 weeks
• Chemotherapy in appropriate
patients for 4-6 months
STAGE
II or III
low/
midlesio
n

91. CURRENT RECOMMENDATION
•Pre or post op
chemoradiation
•TME
Stage II
or III
High
lesion

92. CURRENT RECOMMENDATION
• Palliative surgery
• Adjuvant
chemotherapy
• 5-FU + leucovorin
+/- irinotecan or
oxaliplatin
STAGE
IV

93. SURVEILLANCE
• Screening for rectal recurrence and
metachronous colorectal neoplasm
• 60- 80% recurrence in 24 months, 90% in 48
months
• Each visit DRE+ sigmoidoscopy + CEA
• CT scan : 1 year postresection and then
annually till 3 years

94. SURVEILLANCE
• Postoperative at 2 weeks and then every 3
months for 2 years
• After 2 years every 6 months for 5 years
• If no recurrence, then colonoscopy every 3-5
years
• Close observation for high risk patients

95. Thank You !!