Rectal Carcinoma

Colorectal

Clinicals - History

Fact Explanation
Introduction Colorectal cancer is the third most common cancer worldwide and one third of the colorectal cancers are rectal cancers. Most are adenocarcinomas. 5-year survival rates have been improved with the improved surgery and radiotherapy methods. Introduction
Colorectal cancer is the third most common cancer worldwide and one third of the colorectal cancers are rectal cancers. Most are adenocarcinomas. 5-year survival rates have been improved with the improved surgery and radiotherapy methods.
Bleeding per rectum Rectal bleeding will be ifresh and may either mixed with stools or pass with stools. Bleding may be atributed to haemorrhoids on certain occasions. Bleeding per rectum
Rectal bleeding will be ifresh and may either mixed with stools or pass with stools. Bleding may be atributed to haemorrhoids on certain occasions.
Pain Colorectal carcinoma commonly causes painless bleeding. Pain
Colorectal carcinoma commonly causes painless bleeding.
Tenesmus and sense incomplete evacuation of the rectum Tenesmus is painful desire to defecate without passage of stools. Sense of incomplete evacuation is found in lower GI neoplasms. These symptoms are usually occurred in lower rectal neoplasms. Tenesmus and sense incomplete evacuation of the rectum
Tenesmus is painful desire to defecate without passage of stools. Sense of incomplete evacuation is found in lower GI neoplasms. These symptoms are usually occurred in lower rectal neoplasms.
A period of altering bowel habits Alternating constipation and diarrhoea is a feature of lower GI malignancies. . Lower GI malignancy will lead to obstruction and period of constipation may results.Then due to obstruction inflammatory reaction is taking place over the time and that will cause mucus production and will lead to diarrhoea. A period of altering bowel habits
Alternating constipation and diarrhoea is a feature of lower GI malignancies. . Lower GI malignancy will lead to obstruction and period of constipation may results.Then due to obstruction inflammatory reaction is taking place over the time and that will cause mucus production and will lead to diarrhoea.
Anorexia and weight loss Anorexia and weight loss are systemic manifestation of a malignancy. Anorexia and weight loss
Anorexia and weight loss are systemic manifestation of a malignancy.
Shortness of breath on exertion, lethargy Intermittent chronic blood loss may cause amaemia. Low oxygen to the tissues due to the anaemia, causes lack of energy. Shortness of breath on exertion, lethargy
Intermittent chronic blood loss may cause amaemia. Low oxygen to the tissues due to the anaemia, causes lack of energy.
Hepatic and pulmonary symptoms, neurological defecit such as confusion, headache, somnolance Distant metastases are found in 10%–15% of patients even after complete resection of the colorectal tumour. Liver metastases are found in 20%–30% of patients, and to lung, in 10%–20%. Brain metastases are quite rare. Hepatic and pulmonary symptoms, neurological defecit such as confusion, headache, somnolance
Distant metastases are found in 10%–15% of patients even after complete resection of the colorectal tumour. Liver metastases are found in 20%–30% of patients, and to lung, in 10%–20%. Brain metastases are quite rare.
Family history or personal history of colorectal carcinoma/ adenomatous polyposis Family history of rectal carcinoma and adenomatous polyposis syndrome in any first-degree relative younger than age 60; or a history of colorectal cancer or adenomatous polyps in two or more first-degree relatives at any age increase the risk of rectal carcinoma. The most common inherited conditions are familial adenomatous polyposis (FAP) & hereditary nonpolyposis colorectal cancer (HNPCC), also called Lynch syndrome. HNPCC is due to the mutations in genes MLH1 and MSH2, involved in the DNA repair pathway, and FAP is caused by mutations in the tumor suppressor gene APC. Family history or personal history of colorectal carcinoma/ adenomatous polyposis
Family history of rectal carcinoma and adenomatous polyposis syndrome in any first-degree relative younger than age 60; or a history of colorectal cancer or adenomatous polyps in two or more first-degree relatives at any age increase the risk of rectal carcinoma. The most common inherited conditions are familial adenomatous polyposis (FAP) & hereditary nonpolyposis colorectal cancer (HNPCC), also called Lynch syndrome. HNPCC is due to the mutations in genes MLH1 and MSH2, involved in the DNA repair pathway, and FAP is caused by mutations in the tumor suppressor gene APC.
Diet Increased fat in diet, high intake of red and processed meats, highly refined grains and starches, and reduced fibre are known to increase the risk of colorectal carcinoma. Fiber dilutes or adsorbs fecal carcinogens, modulates colonic transit time, alter bile acid metabolism, reduce colonic pH, or increase the production of short-chain fatty acids, by which it reduces the risk of colorectal cancers. Diet
Increased fat in diet, high intake of red and processed meats, highly refined grains and starches, and reduced fibre are known to increase the risk of colorectal carcinoma. Fiber dilutes or adsorbs fecal carcinogens, modulates colonic transit time, alter bile acid metabolism, reduce colonic pH, or increase the production of short-chain fatty acids, by which it reduces the risk of colorectal cancers.
Usage of Alcohol and Smoking Increases the risk of colorectal carcinoma. Usage of Alcohol and Smoking
Increases the risk of colorectal carcinoma.
Age and sex Colorectal carcinoma are known to be more common in elderly people. More than 90% of colorectal cancer cases occur inthe age group above 50 years. Rectal carcinoma is more common in males compared to females. Age and sex
Colorectal carcinoma are known to be more common in elderly people. More than 90% of colorectal cancer cases occur inthe age group above 50 years. Rectal carcinoma is more common in males compared to females.
History of inflammatory bowel disease There is increased risk for colorectal cancer in patients with inflammatory bowel disease, particularly in long-standing ulcerative colitis. Risk of colorectal cancer in Crohn’s disease is 20 times greater than a control population. History of inflammatory bowel disease
There is increased risk for colorectal cancer in patients with inflammatory bowel disease, particularly in long-standing ulcerative colitis. Risk of colorectal cancer in Crohn’s disease is 20 times greater than a control population.
History of gallstones or cholecystectomy Abnormal bile acid metabolism may facilitate the development of gallstones and may also increase the risk of colon cancer. History of gallstones or cholecystectomy
Abnormal bile acid metabolism may facilitate the development of gallstones and may also increase the risk of colon cancer.

Clinicals - Examination

Fact Explanation
Pallor Anaemia is due to intermittent chronic blood loss , or malignancy induced inflammation. Pallor
Anaemia is due to intermittent chronic blood loss , or malignancy induced inflammation.
Rectal or abdominal mass Mass raises the suspicion of an malignancy particularly when accompanied by weight loss. Rectal or abdominal mass
Mass raises the suspicion of an malignancy particularly when accompanied by weight loss.
Digital rectal examination Finger can reach around 8 cm above the dentate line. Size, ulceration, fixation of the tumor to structures which are surrounding (eg, sphincters, vagina, prostate, coccyx and sacrum) and presence of any pararectal lymph nodes can be assessed using the digital rectal examination. DRE will reveal any polyps, growths, haemorrhoids and ulcers in the anorectal region. Digital rectal examination
Finger can reach around 8 cm above the dentate line. Size, ulceration, fixation of the tumor to structures which are surrounding (eg, sphincters, vagina, prostate, coccyx and sacrum) and presence of any pararectal lymph nodes can be assessed using the digital rectal examination. DRE will reveal any polyps, growths, haemorrhoids and ulcers in the anorectal region.
Wasting Cachexia and anorexia will lead to weight loss and lead to generalized wasting. Wasting
Cachexia and anorexia will lead to weight loss and lead to generalized wasting.
Jaundice, hepatomegaly Liver is a common site of metastases. Jaundice, hepatomegaly
Liver is a common site of metastases.
Respiratory system:dyspnea Liver and lungs are the common sites of metastases as mentioed above. Respiratory system:dyspnea
Liver and lungs are the common sites of metastases as mentioed above.
Focal neurological sign Brain is rarely involvedwith the metastatic disease. Most lesions of the brain are supratentorial. Focal neurological sign
Brain is rarely involvedwith the metastatic disease. Most lesions of the brain are supratentorial.
Obesity Higher body weight and physical inactivity increases the risk of getting colorectal carcinoma. Obesity
Higher body weight and physical inactivity increases the risk of getting colorectal carcinoma.

Investigations - Diagnosis

Fact Explanation
Sigmoidoscopy This is the first line investigation in lower GI bleeding. It usually examine upto splenic flexure of the colon. Intestinal growths, ulcers, polyps etc may be found on sigmoidoscopy. Sigmoidoscopy
This is the first line investigation in lower GI bleeding. It usually examine upto splenic flexure of the colon. Intestinal growths, ulcers, polyps etc may be found on sigmoidoscopy.
Colonoscopy This is an important diagnostic tools to evaluate acute lower gastrointestinal bleeding. Colonoscopy is more sensitive and accurate than sigmoidoscopy in diagnosis. These may be operator dependent. Active bleeding will limit the use of the investigation. It is important to exclude the synchronous lesions in the colon. Colonoscopy
This is an important diagnostic tools to evaluate acute lower gastrointestinal bleeding. Colonoscopy is more sensitive and accurate than sigmoidoscopy in diagnosis. These may be operator dependent. Active bleeding will limit the use of the investigation. It is important to exclude the synchronous lesions in the colon.
Stool occult blood test Stool for occult blood is positive even in asymptomatic people. Stool occult blood test
Stool for occult blood is positive even in asymptomatic people.
Carcinoembryonic antigen (CEA) Plasma level of carcinoembryonic antigen (CEA) is elevated in a suspected case of colorectal malignancy. Carcinoembryonic antigen (CEA)
Plasma level of carcinoembryonic antigen (CEA) is elevated in a suspected case of colorectal malignancy.
CA 19.9 level Carbohydrate antigen 19.9 is elevated in coloretal carcinoma. Carbohydrate antigen 19.9 sensitivity was related to tumor stage. CA 19.9 level
Carbohydrate antigen 19.9 is elevated in coloretal carcinoma. Carbohydrate antigen 19.9 sensitivity was related to tumor stage.

Investigations - Management

Fact Explanation
Colonoscopy Syndromes like heredetery non polyposis colorectal carcinoma (HNPCC) has a high risk of malignant transformation and need regular follow up. It is recommended to screen every 2 yearly from the age of 25, and5 years younger than the earliest affected case in the family up to 75 years. Colonoscopy
Syndromes like heredetery non polyposis colorectal carcinoma (HNPCC) has a high risk of malignant transformation and need regular follow up. It is recommended to screen every 2 yearly from the age of 25, and5 years younger than the earliest affected case in the family up to 75 years.
Full blood count Chronic intermittent bleeding can cause iron deficiency anaemia, which will manifest as low haemoglobin. Full blood count
Chronic intermittent bleeding can cause iron deficiency anaemia, which will manifest as low haemoglobin.
Carbohydrate antigen 19.9 Main use of 19.9 in locoregional cancer is for the prognosis. Carbohydrate antigen 19.9
Main use of 19.9 in locoregional cancer is for the prognosis.
Full blood count Chronic intermittent bleeding can cause iron deficiency anaemia, which will manifest as low haemoglobin, reduced mean corpuscular volume and mean corpuscular haemoglobin with microcytic anaemia and increased red cell distribution width. Full blood count
Chronic intermittent bleeding can cause iron deficiency anaemia, which will manifest as low haemoglobin, reduced mean corpuscular volume and mean corpuscular haemoglobin with microcytic anaemia and increased red cell distribution width.
Electrocardiogram and electrocardiogram Indicated prior to surgery particularly in patients who have a high risk for the cardiovascular morbidities. Electrocardiogram and electrocardiogram
Indicated prior to surgery particularly in patients who have a high risk for the cardiovascular morbidities.
Serum electrolytes and Creatinine These are particularly important in patients with co-morbities like diabetes mellitus or hypertension. Renal functions may be altered i9n metastatic ureteric invasion. Serum electrolytes and Creatinine
These are particularly important in patients with co-morbities like diabetes mellitus or hypertension. Renal functions may be altered i9n metastatic ureteric invasion.
Random blood sugar If patient is diabetic, blood sugar should be repeated on the day of surgery. Random blood sugar
If patient is diabetic, blood sugar should be repeated on the day of surgery.
Prothrombin time and International normalized ratio To detect any bleeding diathesis before surgery. Prothrombin time and International normalized ratio
To detect any bleeding diathesis before surgery.
Liver function tests Liver is a common site of metastatic disease. It is also important to have a base line value in the management of these patients. Liver function tests
Liver is a common site of metastatic disease. It is also important to have a base line value in the management of these patients.
Duke's staging This grading is one of the important prognostic factor in rectal carcinoma. Modified Dukes Classification System involves 4 stages as follows: stage A, limited to the bowel wall, stage B, extension to pericolic fat with no involvement of the lymph nodes, stage C regional lymph node metastases, stage D ditant metastases (liver, lung, bone). It can be further subdivided into stage C1 and C2: positive lymph nodes with no involvement of the apical node as C1 and involvement of the apical nodes as C2. Duke's staging
This grading is one of the important prognostic factor in rectal carcinoma. Modified Dukes Classification System involves 4 stages as follows: stage A, limited to the bowel wall, stage B, extension to pericolic fat with no involvement of the lymph nodes, stage C regional lymph node metastases, stage D ditant metastases (liver, lung, bone). It can be further subdivided into stage C1 and C2: positive lymph nodes with no involvement of the apical node as C1 and involvement of the apical nodes as C2.
CT scan, MRI scan To stage the disease in colorectal carcinoma. CT scan, MRI scan
To stage the disease in colorectal carcinoma.
Carcinoembryonic antigen (CEA) Plasma level of carcinoembryonic antigen (CEA) is measured preoperatively in a suspected case of colorectal malignancy. It may also be elevated in other conditions like gastric carcinoma, pancreatic carcinoma, lung carcinoma, breast carcinoma, and medullary thyroid carcinoma, as well as some non-neoplastic conditions like ulcerative colitis, pancreatitis, cirrhosis, COPD, Crohn's disease. Carcinoembryonic antigen (CEA)
Plasma level of carcinoembryonic antigen (CEA) is measured preoperatively in a suspected case of colorectal malignancy. It may also be elevated in other conditions like gastric carcinoma, pancreatic carcinoma, lung carcinoma, breast carcinoma, and medullary thyroid carcinoma, as well as some non-neoplastic conditions like ulcerative colitis, pancreatitis, cirrhosis, COPD, Crohn's disease.
Screening for rectal carcinoma Many colorectal carcinomas are asymptomatic until a late stage where they cause symptoms due to partial obstruction. Therefore screening for rectal cancer is important in identifying the lesions at an early stage. Average Risk Screening, rigid proctoscopy, sigmoidoscopy, fecal occult blood testing, CT Colonography, stool DNA screening (SDNA), fecal immunochemical test (FIT) etc are some availabla tools of screening for colorectal carcinoma. Fecal occult blood testing is recomended annually for screening with the guaiac-based test with dietary restriction or an immunochemical test without dietary restriction. Screening with flexible sigmoidoscopy/ colonoscopy is done every 5 years where needed. Computed tomography colonography is a novel technique used for colorectal examination. As carcinoma can occur due to the genetic mutations , those can be detected using fecal DNA testing. Screening for rectal carcinoma
Many colorectal carcinomas are asymptomatic until a late stage where they cause symptoms due to partial obstruction. Therefore screening for rectal cancer is important in identifying the lesions at an early stage. Average Risk Screening, rigid proctoscopy, sigmoidoscopy, fecal occult blood testing, CT Colonography, stool DNA screening (SDNA), fecal immunochemical test (FIT) etc are some availabla tools of screening for colorectal carcinoma. Fecal occult blood testing is recomended annually for screening with the guaiac-based test with dietary restriction or an immunochemical test without dietary restriction. Screening with flexible sigmoidoscopy/ colonoscopy is done every 5 years where needed. Computed tomography colonography is a novel technique used for colorectal examination. As carcinoma can occur due to the genetic mutations , those can be detected using fecal DNA testing.

Management - Supportive

Fact Explanation
Patient education and psychological support Educating the patient about the nature of the problem, available treatment options and its side effects, complications including the side effects of radiotherapy and chemotherapy will improve the treatment compliance. Possibility of metastases and recurrences may also need to be told. Particularly stoma care advice has to be given to prevent complications related to the stoma. Patient education and psychological support
Educating the patient about the nature of the problem, available treatment options and its side effects, complications including the side effects of radiotherapy and chemotherapy will improve the treatment compliance. Possibility of metastases and recurrences may also need to be told. Particularly stoma care advice has to be given to prevent complications related to the stoma.
Management of anaemia Anaemia can be due to chronic intermittent blood loss from gastrointestinal tract, malignancy induced inflammation and underlying comorbidities. If significant anaemia present with clinical features they need to get treatment and if needed even blood transfusion. Management of anaemia
Anaemia can be due to chronic intermittent blood loss from gastrointestinal tract, malignancy induced inflammation and underlying comorbidities. If significant anaemia present with clinical features they need to get treatment and if needed even blood transfusion.
Reducing the risk of colorectal carcinoma Clinical trials have shown that aspirin in doses as low as 325 mg per day reduces risk of colorectal carcinoma. Reduction of fat in diet is also an important measure. Avoidance of smoking and heavy alcohol use, prevention of weight gain, and the maintenance of a reasonable level of physical activity are known to lower the risks of colorectal cancer. Simple measures like maintaining adequate fluid intake, eating fresh vegetables, fruits and green leaves, adequate fibre intake and maintaining proper toilet habits are important tp prevent constipation. Reducing the risk of colorectal carcinoma
Clinical trials have shown that aspirin in doses as low as 325 mg per day reduces risk of colorectal carcinoma. Reduction of fat in diet is also an important measure. Avoidance of smoking and heavy alcohol use, prevention of weight gain, and the maintenance of a reasonable level of physical activity are known to lower the risks of colorectal cancer. Simple measures like maintaining adequate fluid intake, eating fresh vegetables, fruits and green leaves, adequate fibre intake and maintaining proper toilet habits are important tp prevent constipation.
Preparing for surgery Preoperative bowel preparation with polyethylene glycol electrolyte solution is given the day before surgery. Counseling on the stoma is given and the site for proximal diversion is marked before surgery. Prophylactic intravenous antibiotics were given at the induction of anesthesia. Preparing for surgery
Preoperative bowel preparation with polyethylene glycol electrolyte solution is given the day before surgery. Counseling on the stoma is given and the site for proximal diversion is marked before surgery. Prophylactic intravenous antibiotics were given at the induction of anesthesia.

Management - Specific

Fact Explanation
Surgery Surgery is the most important part in the treatment of rectal cancer. Stage T1 and T2 local excision is possible. Local excision combine with pre- or postoperative radio-chemotherapy gives the good the outcome. Transanal endoscopic microsurgery (TEM), is a new technique that provides a locally curative operation. High ligation of the interior mesenteric artery, will be beneficial. Minimum margin of mesorectum should be 5 cm. There are main 2 types of surgical options available: Abdominoperineal resection (APR) and anterior resection. Surgery
Surgery is the most important part in the treatment of rectal cancer. Stage T1 and T2 local excision is possible. Local excision combine with pre- or postoperative radio-chemotherapy gives the good the outcome. Transanal endoscopic microsurgery (TEM), is a new technique that provides a locally curative operation. High ligation of the interior mesenteric artery, will be beneficial. Minimum margin of mesorectum should be 5 cm. There are main 2 types of surgical options available: Abdominoperineal resection (APR) and anterior resection.
Anterior resection Anterior resection is a sphincter-sparing operation that gaining the popularity. Anterior resection with mesorectal excision is a safe option that can be done for rectal carcinoma. Some studies have shown that the complete removal of the lymphovascular tissue surrounding the rectum and a free circumferential margin reduces the local recurrence rates in patients with rectal cancer. Peritoneum is incised 1 to 2 cm above the rectouterine or rectovesical pouch. Loop ileostomy is used for the proximal diversion. Anterior resection
Anterior resection is a sphincter-sparing operation that gaining the popularity. Anterior resection with mesorectal excision is a safe option that can be done for rectal carcinoma. Some studies have shown that the complete removal of the lymphovascular tissue surrounding the rectum and a free circumferential margin reduces the local recurrence rates in patients with rectal cancer. Peritoneum is incised 1 to 2 cm above the rectouterine or rectovesical pouch. Loop ileostomy is used for the proximal diversion.
Abdominoperineal resection (APR) Abdominoperineal resection (APR) does not preserve the sphincters. There is no difference in the improvement in the survival and reduction in the local recurrences with APR when compared too AR. APR is better in patients who have poorly differentiated Duke's C tumour with a high risk of distal intramural spread. Abdominoperineal resection (APR)
Abdominoperineal resection (APR) does not preserve the sphincters. There is no difference in the improvement in the survival and reduction in the local recurrences with APR when compared too AR. APR is better in patients who have poorly differentiated Duke's C tumour with a high risk of distal intramural spread.
Transanal Resection & Transanal endoscopic microsurgery (TEM) Transanal excision is done with the conventional technique using traditional equipmentand it provides an easy operative access to most distal rectal lesions. But the disadvantages of the procedure includes, difficulty in conducting on mid-rectal tumors and in large patients with a deep buttock cleft. These can be overcome with the transanal endoscopic microsurgery (TEM) that can be used to treat the early stage rectal cancerand for palliation in advanced rectal cancer in who refuse radical excision/ unfit for surgery. Perforation into the peritoneal cavity and post op haemorrhage are the potential adverse effects of treatment. Transanal Resection & Transanal endoscopic microsurgery (TEM)
Transanal excision is done with the conventional technique using traditional equipmentand it provides an easy operative access to most distal rectal lesions. But the disadvantages of the procedure includes, difficulty in conducting on mid-rectal tumors and in large patients with a deep buttock cleft. These can be overcome with the transanal endoscopic microsurgery (TEM) that can be used to treat the early stage rectal cancerand for palliation in advanced rectal cancer in who refuse radical excision/ unfit for surgery. Perforation into the peritoneal cavity and post op haemorrhage are the potential adverse effects of treatment.
Chemotherapy Intravenous Fluorouracil, oral fluoropyrimidines, angiogenesis Inhibitors, epidermal Growth Factor Receptor Inhibitors in isolation or as combined treatment is used for the systemic therapy in colorectal cancers. Chemotherapy
Intravenous Fluorouracil, oral fluoropyrimidines, angiogenesis Inhibitors, epidermal Growth Factor Receptor Inhibitors in isolation or as combined treatment is used for the systemic therapy in colorectal cancers.
Radiotherapy Peripoerative radiotherapy with dosage > 40 Gy in 3-4 weeks reduces the local recurrence rate. Late complications of the radiotherapy includes increased risks of poor anal and sexual function, small bowel toxicity with obstruction and secondary malignancies. Radiotherapy
Peripoerative radiotherapy with dosage > 40 Gy in 3-4 weeks reduces the local recurrence rate. Late complications of the radiotherapy includes increased risks of poor anal and sexual function, small bowel toxicity with obstruction and secondary malignancies.
Treatment of the recurrances Occasional local recurrences can be managed by chemoradiotherapy and secondary surgery. Treatment of the recurrances
Occasional local recurrences can be managed by chemoradiotherapy and secondary surgery.
Treatment of metastases Most of our patients had supratentorial brain lesions. Other common sites of extracerebral metastase are lung and liver. Patients with metastatic brain lesions are treated with surgery and radiation therapy with addition of corticosteroid treatment on certain occasions. Incorporation of monoclonal antibodies (bevacizumab, cetuximab, panitumumab) into chemotherapeutic regimens have improved the patient survival in colorectal carcinoma. Treatment of metastases
Most of our patients had supratentorial brain lesions. Other common sites of extracerebral metastase are lung and liver. Patients with metastatic brain lesions are treated with surgery and radiation therapy with addition of corticosteroid treatment on certain occasions. Incorporation of monoclonal antibodies (bevacizumab, cetuximab, panitumumab) into chemotherapeutic regimens have improved the patient survival in colorectal carcinoma.

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