Carcinoma rectum & colon
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Carcinoma rectum & colon
- 1. Prof. Khalid Masud Gondal FCPS(Pak),FICS(USA),FCPS(BD),DCPS(HPE) Professor of surgery KEMU Councilor & Regional Director CPSP Lahore Carcinoma Rectum & Colon
- 2. • Starts from caecum to Anal orifice • 150 cm in length • Dentate line – start of Anal sphincter Complex • Fixed positions at the hepatic and splenic flexures • Line of Toldt • Phreno-colic ligament • Peritoneal covering • Ascending & Descending • Transverse & Sigmoid • Rectum 8-10cm 15cm 45 cm 25 cm 10-15 cm 15-50 cm
- 3. Rectum
- 5. BLOODSUPPLY Ileocolic a. Ieft Colic a. Inf. Mesenteric a. Marginal a. Middle Colic a.
- 7. BLOODSUPPLY Left sided Drains To SPLENIC V. Right sided Drains Through SMV
- 8. LYMPHATCDRAINAGE Epicolic nodes are located along the bowel wall and in the epiploicae Epicolic Nodes
- 9. LYMPHATCDRAINAGE Paracolic Nodes are adjacent to Marginal Artery Paracoli c Nodes
- 10. LYMPHATCDRAINAGE Intermediate nodes are located along the main branches of the large blood vessels Intermedi ate Nodes
- 11. LYMPHATCDRAINAGE Primary Nodes are present at the root of the major vessels Primary Nodes
- 13. APC K-ras
- 14. p53
- 15. The Most Common G I Tumour 2nd most common Cause of Malignant Death 3rd Most Common Cause of Death
- 17. Hereditary 1
- 18. Hereditary 1Familial adenomatous polyposis (FAP) 100% Risk Hundreds to Thousands polyps in teenage male (APC Gene) Early progression ( 1 – 5 years) 100% Risk of developin g CRC Early screening & Prophylacti c Surgery Hereditary nonpolyposis colorectal cancer (HNPCC) A few Colorectal Polyps; Right sided Polyps; other visceral tumors Development in 1-3 tears (Mismatch repair gene) 70-80% Life time Risk Early screening & Prophylacti c Surgery Peutz-Jeghers syndrome (PJS) JUVENILE POLYPOSIS SYNDROME (JPS),
- 20. Familial Sporadic 3 Mutation in all cells of the affected individual Genetic polymorphisms, gene modifiers, and defects in tyrosine kinases have all been implicated. First and second degree relatives increase the risk of
- 21. Sporadic 3 Absence of family history An older population (60-80 years of age) Presents as an isolated colon or rectal polyp/ lesion Genetic mutations limited to the tumor itself
- 22. “Presents with aneamia, loss of weight and non specific abdominal symptoms”
- 23. Right Colon FOBC Mass in RIF Weight Loss Aneamia Rectum Tenesmus Pain Bleeding per rectum Constipation Left Colon Obstruction Spurious Diarrheoa Constipation alternating with Diarrheoa Abdominal distention Mucus Discharge per rectum Perforation and peritonitis Metastatsis Ascites Malignant effusion Jaundice Bone & Brain Mets
- 24. Cauliflower/Polypoidal variety Fecal occult Blood culture Mass RIF Weight Loss Anemia Lead point of intussusception Asymptomatic
- 26. • Constricting variety • Constipation • Obstruction • Abdominal distention • Bleeding per rectum • Altered Bowel Habits • Colovaginal/ vesical fistulas
- 27. • Colonic High Risk Low Risk/ Sporadic/ Incidental • Rectal • Metastasis Work up for Colonic & Rectal carcinoma
- 28. • Screening techniques • Workup and Investigations Diagnosis
- 29. 1. Fecal Occult Blood Testing 2. Rigid Proctoscopy 3. Flexible Sigmoidoscopy 4. FOBT and Flexible Sigmoidoscopy 1. Colonoscopy 2. Air-Contrast Barium Enema 3. CT Colonography (Virtual Colonoscopy) • Screen anyone aged above 50 OR • High risk group • Repeat every 10 years
- 30. Procto-sigmoidoscopy / *Inexpensive *Around 50% polyps and Left sided masses are detected *Can be performed on Outpatient basis *Reliable *Biopsy is possible *Polypectomy can be curative *Need to examine whole of the colon till caecum. (10% failure) *Done under sedation *Gut preparation is being carried out
- 32. Ultrasonography
- 33. *Proctoscopy *TRUS *MRI *CT scan *PET Scan USG Abdomen CT scan abdomen and Chest Have a look at patients GCS as well
- 34. *Other investigations in special consideration include CEA levels Urograms Chest isoket Virtual Colonoscopy
Editor's Notes
- The rectum, fecal reservoir. he rectosigmoid junction to be at the level of the sacral promontory; others, at the point at which the taeniae converge. dentate line the distal extent of the rectum, whereas surgeons typically view this union of columnar and squamous epithelium as existing within the anal canal and consider the end of the rectum to be the proximal border of the anal sphincter complex. The rectum is 12 to 15 cm in length and lacks taeniae coli or appendices epiploicae. It occupies the curve of the sacrum in the true pelvis, and the posterior surface is almost completely extraperitoneal in that it is adherent to presacral soft tissues and thus is outside of the peritoneal cavity. The anterior surface of the proximal third of the rectum is covered by visceral peritoneum. The peritoneal reflection is 7 to 9 cm from the anal verge in men and 5 to 7.5 cm in women. This anterior peritonealized space is called the pouch of Douglas or the pelvic cul-de-sac and may serve as the site of so-called drop metastases from visceral tumors. These peritoneal metastases can form a mass in the cul-de-sac (called Bloomer's shelf) that can be detected by a digital rectal examination. The rectum possesses three involutions or curves known as the valves of Houston. The middle valve folds to the left, and the proximal and distal valves fold to the right. These valves are more properly called folds because they have no specific function as impediments to flow. They are lost after full surgical mobilization of the rectum, a maneuver that may provide about 5 cm of additional length to the rectum, greatly facilitating the surgeon's ability to fashion an anastomosis deep in the pelvis. The posterior aspect of the rectum is invested with a thick, closely applied mesorectum. A thin layer of investing fascia (fascia propria) coats the mesorectum and represents a distinct layer from the presacral fascia against which it lies. During proctectomy for rectal cancer, mobilization and dissection of the rectum proceed between the presacral fascia and the fascia propria. Total mesorectal excision is a well-described oncologic maneuver that makes good use of the tissue planes investing the rectum to achieve a relatively bloodless rectal and mesorectal dissection. The lymphatics are contained within the mesorectum, and total mesorectal excision adheres to the basic surgical oncologic principle of removal of the cancer in continuity with its blood and lymphatic supply. Resection of the rectum using this technique and based on a thorough understanding of anatomy has been shown to markedly reduce the incidence of subsequent local recurrence of rectal cancer. Pararectal Fascia The endopelvic fascia is a thick layer of parietal peritoneum that lines the walls and floor of the pelvis. The portion that is closely applied to the periosteum of the anterior sacrum is the presacral fascia. The fascia propria of the rectum is a thin condensation of the endopelvic fascia that forms an envelope around the mesorectum and continues distally to help form the lateral rectal stalks. The lateral rectal stalks or ligaments are actually anterolateral structures containing the middle rectal artery. The stalks reside in close proximity to the mixed autonomic nerves (containing both sympathic and parasympathetic nerves), and division of these structures close to the pelvic sidewall may result in injury to these nerves, resulting in impotence and bladder dysfunction ( Fig. 50-3 ). The rectosacral fascia, or Waldeyer's fascia, is a thick condensation of endopelvic fascia connecting the presacral fascia to the fascia propria at the level of S4 and extends to the anorectal ring. Waldeyer's fascia is an important surgical landmark, and its division during dissection from an abdominal approach provides entry to the deep retrorectal pelvis. Dissection between the fascia propria and the presacral fascia follows the principles of surgical oncology and minimizes the risk for vascular or neural injuries. Disruption of the presacral fascia may lead to injury of the basivertebral venous plexus, resulting in massive hemorrhage. Disrupting the fascia propria during an operation for rectal cancer may significantly increase the incidence of subsequent recurrence of cancer in the pelvis if mesorectum is then left behind.
- Lymph nodes are commonly grouped into levels depending on their location. Epicolic nodes are located along the bowel wall and in the epiploicae. Nodes adjacent to the marginal artery are paracolic. Intermediate nodes are located along the main branches of the large blood vessels; primary nodes are located on the superior or inferior mesenteric artery. Lymph node invasion by metastatic cancer is an important prognostic factor for patients with colorectal cancer. Accurate pathologic assessment of lymph nodes is essential for accurate staging, which serves as a determinant for treatment of patients with colorectal cancer.
- Lymph nodes are commonly grouped into levels depending on their location. Epicolic nodes are located along the bowel wall and in the epiploicae. Nodes adjacent to the marginal artery are paracolic. Intermediate nodes are located along the main branches of the large blood vessels; primary nodes are located on the superior or inferior mesenteric artery. Lymph node invasion by metastatic cancer is an important prognostic factor for patients with colorectal cancer. Accurate pathologic assessment of lymph nodes is essential for accurate staging, which serves as a determinant for treatment of patients with colorectal cancer.
- Lymph nodes are commonly grouped into levels depending on their location. Epicolic nodes are located along the bowel wall and in the epiploicae. Nodes adjacent to the marginal artery are paracolic. Intermediate nodes are located along the main branches of the large blood vessels; primary nodes are located on the superior or inferior mesenteric artery. Lymph node invasion by metastatic cancer is an important prognostic factor for patients with colorectal cancer. Accurate pathologic assessment of lymph nodes is essential for accurate staging, which serves as a determinant for treatment of patients with colorectal cancer.
- Lymph nodes are commonly grouped into levels depending on their location. Epicolic nodes are located along the bowel wall and in the epiploicae. Nodes adjacent to the marginal artery are paracolic. Intermediate nodes are located along the main branches of the large blood vessels; primary nodes are located on the superior or inferior mesenteric artery. Lymph node invasion by metastatic cancer is an important prognostic factor for patients with colorectal cancer. Accurate pathologic assessment of lymph nodes is essential for accurate staging, which serves as a determinant for treatment of patients with colorectal cancer.
- Hereditary forms of colorectal cancer have been extensively described and are characterized by family history, young age at onset, and the presence of other specific tumors and defects. Familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC) have been the subject of many recent investigations that have provided significant insights into the pathogenesis of colorectal cancer.
- Hereditary forms of colorectal cancer have been extensively described and are characterized by family history, young age at onset, and the presence of other specific tumors and defects. Familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC) have been the subject of many recent investigations that have provided significant insights into the pathogenesis of colorectal cancer.
- Hereditary forms of colorectal cancer have been extensively described and are characterized by family history, young age at onset, and the presence of other specific tumors and defects. (FAP) and (HNPCC) have been the subject of many recent investigations that have provided significant insights into the pathogenesis of colorectal cancer. Two less common polyposis syndromes, and are also inherited in an autosomal dominant fashion and are associated with a significant risk of CRC.
- Sporadic colorectal cancer occurs in the absence of family history, generally affects an older population (60-80 years of age), and usually presents as an isolated colon or rectal lesion. Genetic mutations associated with the cancer are limited to the tumor itself, unlike hereditary disease, in which the specific mutation is present in all cells of the affected individual. Nevertheless, the genetics of colorectal cancer initiation and progression proceed along very similar pathways in both hereditary and sporadic forms of the disease. Studies of the relatively rare inherited models of the disease have greatly enhanced the understanding of the genetics of the far more common sporadic form of the cancer. The concept of familial colorectal cancer is relatively new. Lifetime risk for colorectal cancer increases for members in families in which the index case is young (<50 years of age) and the relative is close (first degree). The risk increases as the number of family members with colorectal cancer rises ( Table 50-2 ). An individual who is a first-degree relative of a patient diagnosed with colorectal cancer before the age of 50 years is twice as likely as the general population to develop the cancer. This more subtle form of inheritance is currently the subject of much investigation. Genetic polymorphisms, gene modifiers, and defects in tyrosine kinases have all been implicated in various forms of familial colorectal cancer.
- Sporadic colorectal cancer occurs in , generally affects and usually . , unlike hereditary disease, in which the specific . Nevertheless, the genetics of colorectal cancer initiation and progression proceed along very similar pathways in both hereditary and sporadic forms of the disease. Studies of the relatively rare inherited models of the disease have greatly enhanced the understanding of the genetics of the far more common sporadic form of the cancer. The concept of familial colorectal cancer is relatively new. Lifetime risk for colorectal cancer increases for members in families in which the index case is young (<50 years of age) and the relative is close (first degree). The risk increases as the number of family members with colorectal cancer rises ( Table 50-2 ). An individual who is a first-degree relative of a patient diagnosed with colorectal cancer before the age of 50 years is twice as likely as the general population to develop the cancer. This more subtle form of inheritance is currently the subject of much investigation
- Sporadic colorectal cancer occurs in , generally affects and usually . , unlike hereditary disease, in which the specific . Nevertheless, the genetics of colorectal cancer initiation and progression proceed along very similar pathways in both hereditary and sporadic forms of the disease. Studies of the relatively rare inherited models of the disease have greatly enhanced the understanding of the genetics of the far more common sporadic form of the cancer. The concept of familial colorectal cancer is relatively new. Lifetime risk for colorectal cancer increases for members in families in which the index case is young (<50 years of age) and the relative is close (first degree). The risk increases as the number of family members with colorectal cancer rises ( Table 50-2 ). An individual who is a first-degree relative of a patient diagnosed with colorectal cancer before the age of 50 years is twice as likely as the general population to develop the cancer. This more subtle form of inheritance is currently the subject of much investigation
- The University of Minnesota Colon Cancer Control Study, a large, prospective, randomized trial, was the first of several large studies to conclude that FOBT screening reduces colorectal cancer mortality by 33% and metastatic cases by 50%. However, FOBT is relatively insensitive, missing up to 50% of cancers and the majority of adenomas. Its specificity is low because 90% of patients with positive tests do not have colorectal cancer. Compliance with annual testing is low and costs are significant if one includes the colonoscopy examinations done to evaluate patients with positive FOBT. Nonetheless, the direct evidence that FOBT screening is efficacious and decreases both the incidence and mortality of colorectal cancer is so strong that national guidelines recommend annual FOBT screening for asymptomatic, average-risk Americans older than 50 years of age as one of several accepted strategies. As noted earlier under "Clinical Evaluation," newer immunohistochemical methods for detecting human globin may prove to be more sensitive and specific. 51 A positive FOBT test should be followed by colonoscopy. Rigid Proctoscopy Case control studies show that the risk of dying of rectal cancer is decreased by prior screening via rigid proctoscopy while the risk of colon cancer death is not affected. A study from St. Mark's Hospital in London of more than 1500 patients who underwent rigid proctoscopy and treatment of rectal polyps showed that patients with a single, small tubular adenoma were at low risk of colorectal cancer. In contrast, those with larger tubular, tubulovillous, or villous adenomas were at increased risk for subsequent colon cancer, but at decreased risk for rectal cancer (if the rectal polyps were removed initially). Because of its limited range, proctoscopy has little place in modern screening programs. Flexible Sigmoidoscopy Screening by flexible sigmoidoscopy every 5 years may lead to a 60 to 70% reduction in mortality from colorectal cancer, chiefly by identifying high-risk individuals with adenomas. Presumed high cost has prohibited its use in mass screening in the past, but a randomized, multicenter, controlled trial of screening sigmoidoscopy was initiated by the National Cancer Institute in 1992, and results are expected in 2007. Studies show that trained nurse endoscopists may achieve similar results in polyp detection as their physician colleagues, which may reduce costs considerably. Patients found to have a polyp, cancer, or other lesion on flexible sigmoidoscopy will require colonoscopy. 52 FOBT and Flexible Sigmoidoscopy The FOBT trials from Mandel and associates (University of Minnesota), Hardcastle and associates (England), and Kronberg and associates (Denmark) all showed that FOBT screening was least effective at detecting rectosigmoid cancers. Two-thirds of interval cancers arose in the rectosigmoid in the English series. This is precisely the area screened by flexible sigmoidoscopy; thus, the combination of the two tests has been suggested as a reasonable screening strategy. Winawer, in a study of 12,479 subjects, showed that the combination of FOBT annually with flexible sigmoidoscopy every 5 years resulted in lower mortality from colorectal cancer and better survival in those patients with colorectal cancer. Such data led to the American Cancer Society recommendations that one of the acceptable screening regimens for average-risk Americans is the combination of FOBT annually and flexible sigmoidoscopy every 5 years; this combination was preferred over either test alone. Colonoscopy Colonoscopy is currently the most accurate and most complete method for examining the large bowel. 53 This procedure is highly sensitive for detecting even small polyps (<1 cm) and allows biopsy, polypectomy, control of hemorrhage, and dilation of strictures. However, colonoscopy does require mechanical bowel preparation and the discomfort associated with the procedure requires conscious sedation in most patients. Colonoscopy is also considerably more expensive than other screening modalities and requires a well-trained endoscopist. The risk of a major complication after colonoscopy (perforation and hemorrhage) is extremely low (0.2 to 0.3%). Nevertheless, deaths have been reported. Air-Contrast Barium Enema Air-contrast barium enema is also highly sensitive for detecting polyps greater than 1 cm in diameter (90% sensitivity). Unfortunately, there are no studies proving its efficacy for screening large populations. Accuracy is greatest in the proximal colon but may be compromised in the sigmoid colon if there is significant diverticulosis. For this reason, barium enema is often combined with flexible sigmoidoscopy for screening purposes. The major disadvantages of barium enema are the need for mechanical bowel preparation and the requirement for colonoscopy if a lesion is discovered. CT Colonography (Virtual Colonoscopy) Advances in imaging technology have created a number of less invasive, but highly accurate tools for screening. CT colonography makes use of helical CT technology and three-dimensional reconstruction to image the intraluminal colon. Patients require a mechanical bowel preparation. The colon is then insufflated with air, a spiral CT is performed, and both two-dimensional and three-dimensional images are generated. In the hands of a qualified radiologist, sensitivity appears to be as good as colonoscopy for colorectal cancers and polyps greater than 1 cm in size. 54 Colonoscopy is required if a lesion is identified. CT colonography may also prove useful for imaging the proximal colon in cases of obstruction. Limitations of this technique include false-positive results from retained stool, diverticular disease, haustral folds, motion artifacts, and an inability to detect flat adenomas.
- Colonoscopy is considered the screening gold standard. It is the test of choice for patients with greater-than-average risk and has the advantage of providing a way to intervene in the natural history of colorectal cancer by facilitating endoscopic polypectomy. However, it has several disadvantages. It is the most morbid screening method. Colonic perforation (1 per 2000-1 per 2500 exams), as well as significant bleeding (<1% of exams), can occur. Colonoscopy requires a full bowel preparation accompanied by fasting, sedation, and a skilled endoscopist. Finally, colonoscopy is the most expensive screening test available. Even considering these limitations, the use of colonoscopy has become commonplace. It is the screening test recommended for average-risk individuals; indeed, it may be the most cost-effective test if administered once every 10 years as recommended. For those with greater-than-average risk, colonoscopy is mandatory both for initial screening and for follow-up. Several good studies have endeavored to establish reliable accuracy statistics for colonoscopy. Studies pairing back-to-back colonoscopies have demonstrated a 15% polyp miss rate.[53] In the National Polyp Study Work Group trial, colonoscopic examination revealed a 20% overall polyp miss rate. Clearly, the gold standard could be improved upon, particularly for polyps smaller than 1.0 cm. Email to Colleague Print Version
- Double-contrast barium enema (DCBE) was once the diagnostic mainstay for lower gastrointestinal disease. The advent of flexible fiberoptics has largely supplanted its use. Even so, it has retained a place in the screening armamentarium for the average-risk patient. In 2000, the National Polyp Study Work Group compared DCBE and colonoscopy in a prospective double-blinded trial in patients with a history of polyps.[52] All 862 study subjects underwent both types of exam. Colonoscopists were blinded to the results of the antecedent barium enema. Forty-five percent of colonoscopies revealed adenomatous polyps, compared with only 26% of DCBEs. The rate of detection on DCBE is significantly influenced by size. Only 48% of polyps 1.0 cm or greater in size were detected on DCBE.