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Colorectal Cancer PowerPoint Presentation

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Description : Check out this medical PowerPoint presentation titled "colorectal cancer".
This medical PowerPoint presentation talks about Colorectal cancer, a type of cancer that starts in the colon or rectum. The colon and rectum are part of the large intestine, which is the final part of the digestive system. Colorectal cancer usually begins as small, noncancerous (benign) growths called polyps. Over time, some of these polyps can become cancerous (malignant).
The exact cause of colorectal cancer is not known, but it is thought to be caused by a combination of genetic and environmental factors. Some of the risk factors for colorectal cancer include age (risk increases with age), a family history of the disease, a personal history of colon polyps or inflammatory bowel disease, a diet high in red and processed meats, and a sedentary lifestyle.
Symptoms of colorectal cancer can include changes in bowel habits (such as diarrhea or constipation), blood in the stool, abdominal pain or discomfort, unexplained weight loss, and fatigue. However, some people with colorectal cancer may not experience any symptoms.
Treatment for colorectal cancer may include surgery, chemotherapy, radiation therapy, targeted therapy, or a combination of these treatments, depending on the stage and location of the cancer. Early detection and treatment of colorectal cancer can improve the chances of a successful outcome. It is recommended that people over the age of 50 or those with a family history of colorectal cancer should undergo regular screening tests, such as a colonoscopy, to detect any signs of the disease.

Tags : colorectal cancer, colon, rectum, digestive system, Digestive System, Digestive System PowerPoint presentation

Published on : Mar 27, 2023 | Views : 2053 | Downloads : 1

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Slide 1-

colorectal cancer By Dr. Ryan Al.Ghanemi
Slide 2-

overview of the lecture case presentation. epidemiology of colorectal cancer. clinical presentation of colorectal cancer. staging of colorectal cancer. management of primary colon tumor. management of rectal tumor.
Slide 3-

case presentation A 65 years old man present with dyspnea on exertion and angina for 3-4 weeks. He denies any cough, weight loss, git symptoms. His past medical history is significant for hypertension, stable angina, and colonic polyps Those were removed 7 to 8 years ago by colonoscopy.
Slide 4-

The physical examination reveals a well-nourished man. The finding from head and neck, cardiopulmonary, and neurologic examinations are Unremarkable. Examination of the abdomen reveals an obese abdomen without tenderness or Palpable masses . The rectal examination reveals no masses , a smooth enlarged prostate
Slide 5-

Strongly hemoccult positive stool in the vault . Cbc : hb of 8.7 g/dl hct 29 % and low mcv . Ecg : normal sinus rhythm and mild lvh. Normal chest radiograph.
Slide 6-

What is the most likely mechanism causing this process? How would you confirm the diagnosis ? What is the initial treatment for this pt ?
Slide 7-

Most likely mechanism: anemia caused by occult GI tract bleeding . Confirmation of the diagnosis : EGD and colonscopy. Initial treatment: blood transfusion.
Slide 8-

Epidemiology: Approximately 148,810 new cases of large bowel cancer are diagnosed each year in the United States, of which 108,070 are colon and the remainder rectal cancers. Annually, approximately 49,960 Americans die of CRC, accounting for approximately 9 percent of all cancer deaths.
Slide 9-

Incidence Age is a major risk factor for sporadic CRC. It is a rare diagnosis before the age of 40, the incidence begins to increase significantly between the ages of 40 and 50, and age-specific incidence rates increase in each succeeding decade thereafter).
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The lifetime incidence of CRC in patients at average risk is about 5 percent, with 90 percent of cases occurring after age 50. The incidence is higher in patients with specific inherited conditions that predispose them to the development of CRC.
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A gradual shift toward right-sided or proximal colon cancers has been observed both in the United States and internationally. The greatest increase in incidence is in cecal primaries.
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why this changes? This change in the anatomic distribution of CRCs may be, in part, related to improvements in diagnosis and treatment. and increased screening by flexible sigmoidoscopy with removal of adenomatous polyps in the descending colon . but there also appears to be a true increase in the incidence of ascending colon and cecal cancers .
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Consistent with this hypothesis, five-year survival rates have improved significantly for left and transverse colon cancers, but not for right-sided tumor.
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Risk factors : Environmental and genetic factors can increase the likelihood of developing CRC. Although inherited susceptibility results in the most striking increases in risk. the majority of CRCs are sporadic rather than familial .
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Personal or family history of sporadic cancers or adenomatous polyps — Patients with a personal history of CRC or adenomatous polyps are at risk for the development of a future large bowel cancer
Slide 16-

FAP Hereditary nonpolyposis colorectal cancer A personal history of large (>1 cm) adenomatous polyps and polyps with villous or tubulovillous histology also increase the risk of CRC, particularly if multiple . The relative risk ranges from approximately 3.5 to 6.5 in such patients
Slide 17-

Family history is also an important risk factor in sporadic disease, with a single affected first-degree relative (parent, sibling, or child) increasing the risk 1.7-fold of that in the general population A family history of a large (>1 cm) or histologically advanced colonic adenoma appears to carry the same significance as a positive family history of colorectal cancer
Slide 18-

Inflammatory bowel disease Diabetes mellitus and insulin resistance obesity Cholecystectomy - Alcohol A history of radiation therapy for prostate cancer was associated with an increased risk of rectal cancer in a large database study . The magnitude of risk was similar to that observed in patients with a family history of colonic adenomas
Slide 19-

protective factors Diet Fiber Calcium supplementation has been recommended for the primary or secondary prevention of colonic adenomas by the American College of Gastroenterology
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Aspirin and NSAIDs Hormone replacement therapy
Slide 21-

Omega 3 fatty acids — Consumption of omega 3 fatty acids (mainly as fish oil) has been associated with a reduced incidence of colorectal cancer in observational studies
Slide 22-

Screening: Patient surveillance can most effectively be accomplished by colonoscopy. For average risk individuals ACG colonoscopy every 10 years beginning at 50 years of age . If adenomatous polyp is identified and removed repeat colonoscopy should be done every 3 years when the colon is clear every 5 years . What if he has high risk factor , eg early family history ?
Slide 23-

Clinical presentations: • Abdominal pain — 44 percent • Change in bowel habit — 43 percent • Hematochezia or melena — 40 percent • Weakness — 20 percent • Anemia without other gastrointestinal symptoms — 11 percent Weight loss — 6 percent
Slide 24-

A meta-analysis of 15 studies concluded that the sensitivity of alarm features (such as weight loss) was poor (ranging from 5 to 64 percent). However, the specificity for some alarm symptoms (including dark red rectal bleeding and abdominal mass) was greater than 95 percent.
Slide 25-

Abdominal pain can be caused by a partial obstruction, peritoneal dissemination, or intestinal perforation leading to generalized peritonitis. tenesmus caused by a rectal cancer may involve pelvic floor muscles. a locally advanced lesion may involve the sciatic or obturator nerve, leading to a neuropathic pain syndrome
Slide 26-

Hematochezia is more often caused by a rectal rather than colon cancer A change in bowel habits is a more common presenting symptom for left-sided cancers because fecal contents are liquid in the proximal colon and are therefore less likely to be associated with obstructive symptoms
Slide 27-

Metastatic disease — Approximately 20 percent of patients have distant metastatic disease at the time of presentation The presence of right upper quadrant pain, abdominal distention, early satiety, supraclavicular adenopathy, or periumbilical nodules usually signals advanced disease.
Slide 28-

Because the venous drainage of the intestinal tract is via the portal system, the first site of hematogenous dissemination is usually liver tumors arising in the distal rectum may metastasize initially to the lungs because the inferior rectal vein drains into the inferior vena cava rather than into the portal venous system.
Slide 29-

Unusual presentations — There are also a variety of unusual presentations of CRC. These include: Local invasion or a contained perforation causing malignant fistula formation into adjacent organs Fever of unknown origin CRC ultimately proves to be the origin of approximately 6 percent of adenocarcinomas of unknown primary sites
Slide 30-

Impact of symptoms on prognosis — The presence of symptoms and their particular type appear to be of some prognostic importance:
Slide 31-

• Patients who are symptomatic at diagnosis have a somewhat worse prognosis . In one report, the five-year survival rate for symptomatic and asymptomatic patients was 49 versus 71 percent. the duration of symptoms is not an accurate predictor of prognosis.
Slide 32-

• Obstruction and/or perforation, although uncommon, carry a poor prognosis, independent of stage . • Tumors presenting with hemorrhage have been thought to have a better prognosis because of their tendency to be diagnosed earlier; however, bleeding is not an independent predictor of outcome .
Slide 33-

LOCATION OF COLORECTAL MALIGNANCIES Synchronous cancers — Synchronous CRCs: defined as two or more distinct primary tumors separated by normal bowel and not due to direct extension or metastasis, occur in 3 to 5 percent of patients with colon cancer
Slide 34-

Metachronous cancers : Metachronous CRCs, defined as nonanastomotic new tumors developing at least six months after the initial diagnosis. develop in 1.5 to 3 percent of patients in the first five years postoperatively, rising to up to 9 percent after several decades in survivors of the primary cancer
Slide 35-

DIAGNOSIS CRC may be suspected from one or more of the symptoms and signs described above or may be asymptomatic and discovered by routine screening of average and high risk subject
Slide 36-

Colonoscopy and BE The vast majority of colon and rectal cancers are endoluminal adenocarcinomas that arise from the mucosa. Colonoscopy is the single best diagnostic test in symptomatic individuals, since it can localize lesions throughout the large bowel, biopsy mass lesions, detect synchronous neoplasms, and remove polyps The air contrast barium enema (BE), supplemented with flexible sigmoidoscopy, is also used to evaluate symptomatic patients
Slide 37-

A direct evaluation of the total colonic mucosa is necessary to exclude carcinoma with certainty
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staging Tx: No description of the tumor's extent is possible because of incomplete information. Tis: The cancer is in the earliest stage. It involves only the mucosa. It has not grown beyond the muscularis mucosa (inner muscle layer). T1: The cancer has grown through the muscularis mucosa and extends into the submucosa. T2: The cancer has grown through the submucosa and extends into the muscularis propria (outer muscle layer).
Slide 40-

T3: The cancer has grown through the muscularis propria and into the subserosa but not to any neighboring organs or tissues. T4: The cancer has grown through the wall of the colon or rectum and into nearby tissues or organs.
Slide 41-

N categories for colorectal cancer N categories indicate whether or not the cancer has spread to nearby lymph nodes and, if so, how many lymph nodes are involved. Nx: No description of lymph node involvement is possible because of incomplete information. N0: No lymph node involvement is found. N1: Cancer cells found in 1 to 3 nearby lymph nodes. N2: Cancer cells found in 4 or more nearby lymph nodes.
Slide 42-

M categories for colorectal cancer M categories indicate whether or not the cancer has spread to distant organs, such as the liver, lungs, or distant lymph nodes. Mx: No description of distant spread is possible because of incomplete information. M0: No distant spread is seen. M1: Distant spread is present.
Slide 43-

Stage 0 Tis, N0, M0: The cancer is in the earliest stage. It has not grown beyond the inner layer (mucosa) of the colon or rectum. This stage is also known as carcinoma in situ or intramucosal carcinoma. Stage I T1, N0, M0 or T2, N0, M0: The cancer has grown through the muscularis mucosa into the submucosa (T1) or it may also have grown into the muscularis propria (T2). It has not spread to nearby lymph nodes or distant sites.
Slide 44-

Stage IIA T3, N0, M0: The cancer has grown into the outermost layers of the colon or rectum but has not reached nearby organs. It has not yet spread to the nearby lymph nodes or distant sites. Stage IIB T4, N0, M0: The cancer has grown through the wall of the colon or rectum and into other nearby tissues or organs. It has not yet spread to the nearby lymph nodes or distant sites.
Slide 45-

Stage IIIA T1, N1, M0 or T2, N1, M0: The cancer has grown through the mucosa into the submucosa (T1) or it may also have grown into the muscularis propria (T2). It has spread to 1 to 3 nearby lymph nodes but not to distant sites. Stage IIIB T3, N1, M0 or T4, N1, M0: The cancer has grown into the outermost layers of the colon or rectum but has not reached nearby organs (T3) or the cancer has grown through the wall of the colon or rectum and into other nearby tissues or organs (T4). It has spread to 1 to 3 nearby lymph nodes but not distant sites.
Slide 46-

Stage IIIC Any T, N2, M0: The cancer may or may not have grown through the wall of the colon or rectum, but it has spread to 4 or more nearby lymph nodes. It has not spread to distant sites. Stage IV Any T, Any N, M1: The cancer may or may not have grown through the wall of the colon or rectum, and it may or may not have spread to nearby lymph nodes. It has spread to distant sites such as the liver, lung, peritoneum (the membrane lining the abdominal cavity), or ovary.
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Slide 48-

An increase in colorectal cancer screening has been associated with an earlier stage at which colorectal cancer is diagnosed. The following results were observed in a large database study • Localized — confined to the primary site and to the mucosa, submucosa, and muscle layer (Dukes' A or B or TNM stage I or II ) — 40 percent • Lymph node involvement (Dukes' C or TNM stage III) — 37 percent • Distant metastases (Dukes' D or TNM stage IV) — 19 percent
Slide 49-

As a general rule, the stage of rectal cancer at diagnosis tends to be slightly earlier than the stage in the colon probably because rectal cancers are more likely to cause symptoms.
Slide 50-

In patients with four or fewer hepatic lesions, resection may be curative, with five-year relapse-free survival rates of 24 to 38 percent
Slide 51-

Intraoperative evaluation — Even if preoperative clinical staging evaluation fails to show evidence of metastatic spread. intraoperative evaluation is an essential component of the clinical staging process. CT scan is not a reliable diagnostic test for low volume tumor on peritoneal surfaces.
Slide 52-

EUS for rectal cancer — Preoperative knowledge of the depth of invasion and nodal status is critically important for planning therapy of a rectal cancer. Neoadjuvant combined modality approaches utilizing both chemotherapy and radiation are associated with less toxicity and a higher likelihood of sphincter preservation, particularly for distal transmural tumors.
Slide 53-

Tumor markers : An expert panel on tumor markers in breast and colorectal cancer convened by the American Society of Clinical Oncology (ASCO) recommended that serum CEA nor CA 19-9 levels not be used as a screening test for colorectal cancer . A similar recommendation has been made by the European Group on Tumor Markers . However, serum levels of CEA do have prognostic utility in patients with newly diagnosed CRC. Patients with preoperative serum CEA >5 ng/mL have a worse prognosis, stage for stage, than those with lower levels
Slide 54-

PROGNOSIS : Colon cancer — Five-year survival rates in a contemporary series of over 119,000 patients treated between 1991 and 2000 stratified according to the most recent modification of the TNM staging system were as follows: • Stage I (T1-2N0) — 93 percent • Stage IIA (T3N0) — 85 percent • Stage IIB (T4N0) — 72 percent • Stage IIIA (T1-2 N1)— 83 percent • Stage IIIB (T3-4 N1) — 64 percent • Stage IIIC (N2) — 44 percent Stage IV — 8 percent
Slide 55-

Survival rates in patients with stage II and III disease are variable and depend on the number of lymph nodes analyzed . Rectal cancer — Five-year survival rates for rectal cancer tend to be somewhat lower and are heavily dependent upon case mix .
Slide 56-

In particular, the survival of patients with stage III disease is variable and depends upon the T stage (ie, T1-2 versus 3-4) and the extent of nodal disease. As an example, when data from the National Cancer Database were stratified according to subsets of stage III disease, the following five-year survival rates were reported :
Slide 57-

• Stage IIIA (T1-2, N1) — 55.1 percent (n = 1043 patients) • Stage IIIB (T3-4, N1) — 35.3 percent (n = 2856 patients) • Stage IIIC (Any T, N2) — 24.5 percent (n = 2088 patients)
Slide 58-

Surgical management of primary colon cancer Surgery is the only curative modality for localized colon cancer. Surgery also provides a potentially curative option for selected patients with limited metastatic disease in liver and/or lung.
Slide 59-

PREOPERATIVE EVALUATION : A complete history and physical examination should be performed in all patients presenting with a newly diagnosed colon cancer The preoperative evaluation should also include a complete blood count, serum electrolytes, liver enzymes, and carcinoembryonic antigen (CEA), urinalysis, coagulation profile, electrocardiogram, chest x-ray, and computed tomography (CT) scan of the abdomen and pelvis Ideally, each patient should have a colonoscopic examination of the entire colon prior to surgery.
Slide 60-

Endoscopic ultrasound — Endoscopic ultrasound (EUS) is not routinely used in the preoperative or staging workup of colon cancer (in contrast to rectal cancer, where it is routinely used).
Slide 61-

GENERAL SURGICAL PRINCIPLES The goal of colon cancer surgery is complete removal of the tumor along with the major vascular pedicle feeding the affected colonic segment and the lymphatic drainage basin En bloc resection of contiguous structures is indicated if there is attachment or adhesion of the tumor to any organ or structure.
Slide 62-

Bowel preparation Preoperative mechanical bowel preparation (MBP) reduces both the fecal content and bacterial count in the bowel lumen . The use of MBP in conjunction with prophylactic antibiotics has been reported to decrease the incidence of wound infection and intraabdominal abscess after colorectal surgery . Some have questioned the need for routine MBP prior to elective colon cancer surgery.
Slide 63-

In an early systematic review of randomized trials of preoperative MBP versus no MBP in 1592 patients (nine trials) undergoing elective colorectal surgery, there was no significant difference in the anastomotic leakage rate between patients who had versus did not have MBP (2.9 versus 1.6 percent, respectively) . Furthermore, there was a nonsignificant trend toward a higher incidence of wound infection in patients who received MBP (7.4 versus 5.4 percent).
Slide 64-

Resection margins — Proximal and distal resection margins should be at least 5 cm from the tumor . Regional lymphadenectomy — Regional lymphadenectomy provides important prognostic information that guides adjuvant treatment and is of therapeutic value as well.
Slide 65-

SURGICAL TECHNIQUES Right hemicolectomy : A right hemicolectomy is usually performed for tumors of the cecum and ascending colon, and for some hepatic flexure. In a classic right hemicolectomy, the ileocolic, right colic, and right branch of the middle colic vessels are divided and removed with the contiguous mesentery. Care must be taken to identify the right ureter, the ovarian or testicular vessels, and the duodenum. If the omentum is attached to the tumor, it should be removed en bloc with the specimen.
Slide 66-

Extended right hemicolectomy An extended right hemicolectomy can be performed for proximal, mid, or even distal transverse colon cancers, although tumors of the distal transverse colon are more often resected with a left hemicolectomy. In the extended right hemicolectomy, the ileocolic, right colic, and middle colic vessels with their contiguous mesentery are divided and removed. The inferior mesenteric vein may be divided and included in the specimen. Care must be taken to protect the duodenum and the pancreas
Slide 67-

Transverse colectomy A transverse colectomy may be undertaken for mid transverse colon cancers as long as satisfactory resection margins and an adequate lymphadenectomy can be obtained. The transverse colon is resected along with the middle colic vessels and its mesentery. At times, the inferior mesenteric vein is also divided and included in the resected specimen. Both the hepatic and splenic flexures may need to be mobilized in order to achieve a tension-free anastomosis. When mobilizing the splenic flexure, care must be taken not to apply much traction to the omentum or colon, as this will invariably result in splenic capsule tears.
Slide 68-

Left hemicolectomy A left hemicolectomy is appropriate for tumors in the distal transverse or descending colon and for selected patients with proximal sigmoid colon cancer. The left branch of the middle colic vessels, the inferior mesenteric vein, and the left colic vessels along with their mesenteries are included with the specimen. In some cases, a segmental colectomy may be performed as long as adequate resection margins and lymphadenectomy are achieved .
Slide 69-

Sigmoid colectomy For sigmoid colon cancers, segmental or sigmoid colectomy is appropriate. The inferior mesenteric artery is divided at its origin, and dissection proceeds just under the superior rectal vessels toward the pelvis until adequate margins are obtained. As with right-sided tumors, care must be taken while mobilizing the sigmoid and descending colon to identify the left ureter and the left ovarian or testicular vessels.
Slide 70-

Subtotal and total colectomy A subtotal or a total abdominal colectomy is indicated if there are synchronous neoplasms on the right and left sides of the colon. Occasionally these procedures are performed in patients presenting with obstructing-left sided tumors. For patients with hereditary nonpolyposis colorectal cancer (HNPCC) who present with a colon cancer, total abdominal colectomy is the procedure of choice. .
Slide 71-

Locally advanced primary lesions — Approximately 10 percent of patients with colon cancer have invasion of contiguous organs or inflammatory adhesions involving neighboring structures
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Benefit of postoperative RT There is a paucity of high-quality evidence addressing the role of adjuvant RT (with or without concurrent chemotherapy) in patients with resected locally advanced colon cancer
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current treatment recommendations suggest that adjuvant RT be offered to the following subgroups of patients who have an estimated risk of local recurrence that is 30 percent or higher: T4 disease, positive resection margins, disease complicated by perforation or abscess formation
Slide 74-

Neoadjuvant chemoradiotherapy Neoadjuvant (preoperative) chemoradiotherapy may represent an alternative approach for selected patients with locally advanced colon cancer invading into adjacent organs. However, there is no consensus as to which patients are suitable for this approach. Although commonly used for locally advanced rectal cancers.
Slide 75-

patients with obstruction Optimal management for an obstructing cancer depends upon the condition of the patient and the tumor location. If the patient is a candidate for surgery, surgical treatment alternatives for obstructing colon cancers include resection of the tumor with a primary anastomosis with or without a temporary proximal diversion, resection without an anastomosis and with an end colostomy, and proximal diversion with a mucous fistula or a loop colostomy, to temporize the situation with an elective definitive resection at a second operation
Slide 76-

patients with perforation The management of perforated tumors has to be individualized. Treatment alternatives will depend on the patient's overall condition and whether peritonitis is localized or generalized. If the patient is stable and peritonitis is not generalized, tumor resection with a primary anastomosis can be performed. As noted above, primary anastomosis is not recommended if there is diffuse peritonitis or free perforation and/or the patient is medically unstable.
Slide 77-

For an unstable patient, percutaneous drainage or a proximal diverting colostomy can be performed. Chemotherapy — Obstructed and perforated colon cancers are considered at high risk for recurrence. Guidelines from ASCO suggest the use of adjuvant chemotherapy in these settings, even for node-negative disease.
Slide 78-

LAPAROSCOPIC COLECTOMY Laparoscopic-assisted colectomy (LAC) was first described in 1991 . However, because of concerns over port site recurrences and the adequacy of the oncologic procedure, LAC was not accepted by the surgical community until the completion of multiple studies comparing safety and oncologic equivalency to open colectomy
Slide 79-

At least six large (100 or more patients) prospective randomized controlled trials have now been reported, and none suggest a significant detrimental impact on recurrence or survival for laparoscopic as compared to open resection In the earliest trial from Barcelona ( a median follow-up of 94 months, overall and disease-free survival were similar in both groups institution study),
Slide 80-

In the largest trial, the United States Intergroup At a median follow-up of seven years, there were also no significant differences in the five-year disease-free survival (69 versus 68 percent in the LAC and open colectomy groups, respectively) or overall survival (76 versus 75 percent).
Slide 81-

Both concluded that laparoscopic colectomy provides oncologic outcomes (cause-specific survival, disease recurrence, number of lymph nodes harvested) that are comparable to those achieved with an open approach.
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MANAGEMENT OF CARCINOMA IN A POLYP Endoscopic resection alone is a reasonable approach for favorable-risk early stage colon cancers arising in a polyp. The presence of any of the following factors should prompt consideration of radical surgery, as they indicate a higher risk of residual cancer and/or nodal metastases:
Slide 84-

• Poorly differentiated histology • Lymphovascular invasion • Cancer at the resection or stalk margin • Invasion into the muscularis propria of the bowel wall (T2 lesion) • Invasive carcinoma arising in a sessile (flat) polyp • Invasive carcinoma with incomplete polypectomy
Slide 85-

• Lymphovascular invasion • Cancer at the resection or stalk margin • Invasion into the muscularis propria of the bowel wall (T2 lesion)
Slide 86-

Surgical management of rectal cancer Physical and endoscopic examination — Digital rectal examination (DRE) and rigid sigmoidoscopy are essential to the surgical decision-making process The type of operation offered to a patient with rectal cancer depends on tumor stage and location
Slide 87-

If sphincter preservation is to be achieved, the tumor has to be located high enough above the top of the anorectal ring to allow for an adequate distal margin. This is more likely with midrectal and upper rectal tumors than for distal tumors (within 5 cm of the anal verge), although preoperative chemoradiotherapy may permit sphincter preservation in some patients with low-lying tumors.
Slide 88-

GENERAL SURGICAL PRINCIPLES After establishing the diagnosis and completing the staging workup, a decision is made whether to pursue immediate resection or attempt preoperative chemoradiotherapy . The benefits of preoperative chemoradiotherapy were best demonstrated in the German Rectal Cancer Study Group trial that randomly assigned 823 patients with rectal cancer to preoperative versus postoperative chemoradiotherapy .
Slide 89-

The following results were noted: • Patients treated preoperatively had similar survival rates but a significantly lower pelvic relapse rate compared to those receiving postoperative chemoradiotherapy. Overall rates of sphincter preservation were similar in both groups (APR required by 26 and 23 percent of preoperatively and postoperatively treated patient.
Slide 90-

Goals of surgery: The primary goal of surgery is complete removal of the primary tumor along with the regional lymphatics and the superior hemorrhoidal artery pedicle. The surgical specimen should contain at least 12 lymph nodes
Slide 91-

SELECTION OF APPROPRIATE SURGERY The surgeon has three major curative options for rectal cancer: local excision, sphincter-preserving abdominal surgery (low anterior resection or LAR), and abdominal perineal resection (APR). The depth of tumor invasion into the rectal wall, the presence or absence of regional lymph node metastases, the size and macroscopic appearance of the cancer, and tumor location are all critical in determining the best surgical option
Slide 92-

Abdominal perineal resection (APR): An APR requires incisions in both the abdomen and perineum. It entails removal of the primary tumor along with a complete proctectomy, resulting in the need for a permanent colostomy. APR has long been considered the gold standard for surgical therapy of distal rectal cancers. Oncologic outcomes following LAR are not significantly different from those after APR .
Slide 93-

However, compared to LAR, APR is associated with higher procedure-related morbidity and mortality . and an inferior quality of life (QOL), mainly related to depression and changes in body image .
Slide 94-

Sphincter-sparing procedures : Sphincter-sparing approaches for distal rectal cancers have evolved along two pathways: For larger or more invasive tumors of the distal rectum (eg, T3 or T4 lesions), preoperative or neoadjuvant chemoradiotherapy may facilitate the conversion of a planned APR to a LAR by promoting tumor regression For small rectal cancers that are confined to the rectal wall, local excision techniques may offer local control and survival rates that are comparable to APR, while preserving sphincter function
Slide 95-

Low anterior resection — Most invasive rectal cancers involving the upper third of the rectum can be adequately treated by a LAR, preserving the anal sphincter. Even for patients with midrectal and some distal (lower third) rectal cancers, LAR has become increasingly prevalent as the safety and efficacy has been established
Slide 96-

THANK YOU Dr. Ryan Al.Ghanemi