Colorectal Cancer
Colorectal cancer is a malignant tumour that can be located at different levels inside the large intestine. It can be located at the level of the colon or at the end of the intestine, in the area called rectum.
How frequent is colon cancer?
1.-Cancer of the colon is the second most frequent neoplasia, after breast cancer in women and lung cancer in men.
2.- It is the most malignant digestive neoplasia in the western World, with a higher incidence than that of all the other tumours combined.
What is its the exact incidence in other countries?
1.- In the United Status and New Zeeland there are 50 cases every 100,000 inhabitants.
2.- In Senegal, Colombia and India, less than 10 cases every 100,000 inhabitants.
What is its exact incidence in Spain?
31 cases per 100,000 male inhabitants and 21 cases per 100,000 female inhabitants.
Is there any difference between genders?
It is believed that this type of cancer affects men and women alike, although recent studies have shown that cancer of the colon is more frequent in woman and cancer of the rectum is more frequent in men.
It is believed that colorectal cancer is caused by a combination of genetic and environmental factors. The individual´s predisposition to colorectal cancer is determined by their heredity, whilst environmental factors interact with this susceptibility to give raise to small adenomatous polyps, larger adenomatous polyps and, finally, cancer.
If a person has one or more of these symptoms, could it be cancer?
No, as there are other diseases that can also present with the same symptoms.
How can cancer be detected and what symptoms should you consult for with a physician?
1.- Loss of red blood mixed with faeces or dark blood
2.- Alterations in the normal habit of defecating: development of constipation or diarrhoea.
3.- When no complete defecation is noted.
4.- Weight loss, tiredness, loss of appetite.
5.- Ferropenic anaemia (due to lack of iron).
6.- When the abdomen is painful and after a bowel movement or expulsion of gases, the pain disappears partially.
In these cases, you should see your physician for referral to a specialist.
If a person has one or more of these symptoms, could it be cancer?
No, as there are other diseases that can also present with the same symptoms.
What to do?
The first thing to do is to go to a specialist. The specialist will choose and decide what tests to run.
What can one do to watch for and to prevent cancer of the large intestine?
There are two ways.
1.- Test for identifying blood in faeces. This test should be done every year and three consecutive days each year. This test should be complemented by a sigmoidoscopy every 3 to 5 years.
2.- Complete colonoscopy every 10 years, or more often depending on the clinical findings.
What tests are there to confirm or rule out a diagnosis of colorectal cancer?
Colonoscopy, Virtual colonoscopy, Flexible sigmoidoscopy, Rectal palpation, Histology.
Why and where does colon cancer develop?
The microarchitecture of the colon is formed by crypts. These crypts have at their base – the deepest and furthest part from the intestinal lumen- progenitor cells, that is, immature cells that start to differentiate and finally, when they are already differentiated, they go up to the crypt surface and arrange themselves in contact with the intestinal lumen (superficial mature cells).
1) The majority of colorrectal cancers (75%) are sporadic and appear prompted by environmental or dietetic factors. We can say that in the general population it occurs in a 5% throughout life.
2) Between 20 to 25% have a genetic component. In some cases, this means an earlier onset of the tumour in sporadic cases. The risk that a first-grade relative has is greater than that of the rest of the population. Because of this, in those cases, it is mandatory to have information on the familial past history.
What should one do when colorectal cancer is suspected?
You should seek medical advice to undergo a risk assessment.
Who decides which family members to test?
The specialist doctor.
Why is it necessary to have a genetic test?
Because the test attempts to identify people who are highly likely to present associated genetic alterations. If we know who is more at risk, we will be able to do a proper preventive follow up at short term in order to detect any possible alteration at long term.
Who should carry out the screening or follow-up?
The specialist doctor.
Diagnostic Methods
Colonoscopy
author/s: Dra. Mª del Carmen Peña Cala, Dr. Javier Nebreda
It is an internal examination of the colon that uses an instrument called colonoscope consisting of a small camera adhered to a flexible tube.
Virtual colonoscopy
author/s: Dra. Dolores Maluenda
A VC is a scanner or CAT (computerised axial tomography) – computerised radiography- that, presents as one of its innovations, the capture of an image from several angles.
Flexible sigmoidoscopy
author/s: Dr. Javier Nebreda
This technique consists in introducing a thin tube with a light through the rectum for about 60 cm to look for polyps, anormal areas and cancer.
Opaque enema
author/s: Dra. Dolores Maluenda Colomer
An opaque enema is a radiological technique that enables visualisation of the shape of the colon after introducing a barium contrast through the rectum.
Rectal palpation
author/s: Dra. Dolores Maluenda Colomer
Histology
author/s: Dr. Javier Nebreda
What is a polyp? What polyps have the highest risk for malignisation? What histological types of colorectal cancer exist?
Colonoscopy
author/s: Dra. Mª del Carmen Peña Cala, Dr. Javier Nebreda
It is an internal examination of the colon that uses an instrument called colonoscope consisting of a small camera adhered to a flexible tube.
Virtual colonoscopy
author/s: Dra. Dolores Maluenda
A VC is a scanner or CAT (computerised axial tomography) – computerised radiography- that, presents as one of its innovations, the capture of an image from several angles.
Flexible sigmoidoscopy
author/s: Dr. Javier Nebreda
This technique consists in introducing a thin tube with a light through the rectum for about 60 cm to look for polyps, anormal areas and cancer.
Opaque enema
author/s: Dra. Dolores Maluenda Colomer
Rectal palpation
author/s: Dra. Dolores Maluenda Colomer
Histology
author/s: Dr. Javier Nebreda
What is a polyp? What polyps have the highest risk for malignisation? What histological types of colorectal cancer exist?
How does colorectal cancer spread?
When a polyp starts to get malignant, it starts to grow and goes through the different layers of the wall of the colon or rectum, depending on its location. Later on, and through the lymph system, it can invade nodes and through the blood stream reach other organs, mainly the liver and lungs (metastasis). It can also cause tumours inside the abdomen.
The extension of the tumour will be complemented with imaging tests, including ultrasound , CAT, and/or MNR (magnetic nuclear resonance).
Therapeutic Options
Therapeutic endoscopy
Therapeutic colonoscopy consists in the application of different treatments through the colonoscope. The most common procedures are: Polypectomy, Mucosectomy, etc.
Therapeutic endoscopy
Therapeutic colonoscopy consists in the application of different treatments through the colonoscope. The most common procedures are: Polypectomy, Mucosectomy, etc.
Surgery of the colon and rectum
The objective of the operation is to resect the portion of the thick intestine encompassing the tumour, as well as the entire territory of lymphatic drainage.
Surgery of the colon and rectum
The objective of the operation is to resect the portion of the thick intestine encompassing the tumour, as well as the entire territory of lymphatic drainage.
TEM Surgery
TEM Surgery
Medical oncology
Tumour staging consists in the prognostic classification of a neoplastic disorder. Staging is required in all tumours and depending on the prognosis of the disease, a series of either surgical, chemotherapy or radiotherapy treatments are then decided upon.
Medical oncology
Tumour staging consists in the prognostic classification of a neoplastic disorder. Staging is required in all tumours and depending on the prognosis of the disease, a series of either surgical, chemotherapy or radiotherapy treatments are then decided upon.
Radiation Oncology
Radiotherapy consists in the administration of ionising radiations that prompt cell alterations and in a much more important way in the tumour cells
Radiation Oncology
Radiotherapy consists in the administration of ionising radiations that prompt cell alterations and in a much more important way in the tumour cells
Prognosis
Fortunately, colorectal cancer is not one of the most aggressive types of tumour. The possibilities of cure vary greatly and depend on when the lesion is detected. If the lesion is detected very early, these possibilities of cure reach nearly 100%. After the initial stages, the possibilities of cure start to decrease. We could say that there are several levels of severity. These levels include whether or not the tumour has spread beyond the entire wall of the intestine, and if so, whether or not the lymph nodes are involved, and lastly, whether it has invaded other organs (metastasis). Despite all of this, even in cases where the cancer has spread to other organs, there are options for cure or at least to stop disease progression.
Prognosis
Fortunately, colorectal cancer is not one of the most aggressive types of tumour. The possibilities of cure vary greatly and depend on when the lesion is detected. If the lesion is detected very early, these possibilities of cure reach nearly 100%. After the initial stages, the possibilities of cure start to decrease. These levels include whether or not the tumour has spread beyond the entire wall of the intestine, and if so, whether or not the lymph nodes are involved, and lastly, whether it has invaded other organs (metastasis). Despite all of this, even in cases where the cancer has spread to other organs, there are options for cure or at least to stop the disease progression.
Genetics
Early detection
Author: Dr. Xavier Llor Farré
Colorectal cancer is a very slow growing cancer. Furthermore, there are now techniques available that enable detection even at the initial stages of development of this type of cancer The most efficient type is colonoscopy. If colorectal cancer is detected by means of this technique and it is still small, it can be surgically removed at the same time the test is done.
The methods used for early detection are hidden blood in the faeces, colonoscopy, opaque enema, and still under validation, virtual colonoscopy. Different strategies have been designed that employ one or more of these tests with a good percentage of detections.
Without a doubt, colonoscopy is the definitive test for diagnosis. Colonoscopy not only detects cancer but also allows the clinician to do a biopsy to analyse the tumour. Tests that check for hidden blood in the faeces, in combination with colonoscopy, have proven very efficient. The simplicity of the first allows for a general screening of the population with no risk and good effectiveness. However, in the end, all these tests require a colonoscopy if any abnormality has been detected. This is the only detect providing a definitive diagnosis.
The risk to suffer from colorectal cancer increases noticeably after the age of 50. Nevertheless, there are some circumstances that make a certain individual be at higher risk, and thus, such individual should be monitored earlier. We are referring to people who have a relative with this type of cancer, people with different types of cancer in the family, patients with a history of intestinal inflammatory diseases, and above all, people with familial syndromes of colorectal cancer, such as the Adenomatous Polyposis Syndrome or Lynch´s syndrome.
The most important thing is to detect this type of cancer when it is still hidden. This is the best stage to catch in time. The symptoms usually appear when the tumour has already reached a considerable size and the tumour is already at an advanced stage. The best time to detect this cancer is when the patient is feeling OK and nothing is suggestive of cancer. The signs and symptoms that might accompany colorectal cancer are: rectal bleeding, stomach pain, pain in the intestine, changes in the size and frequency of bowel movements, or anaemia.
Heredity
Author: Dr. Xavier Llor Farré
Have I or have I had relatives with this or with other types of cancer?
One of the most important factors concerning the risk of colorectal cancer has to do with whether we have had one or more relatives diagnosed with this type of cancer or whether there have been other types of cancer in the family. Even though the highest percentage of colorectal cancer appears in people with no familial history, the risk of a person to suffer from this type of cancer is higher if there is a familial past history The higher the number of affected relatives, the greater the risk will be. A different matter is families with hereditary syndromes such as familial adenomatous polyposis or Lynch´s syndrome in which the risk to suffer from colorectal cancer for each member of the family nearly reaches 50%.
Is colorectal cancer inherited?
The hereditary component in this type of cancer is very important. We already know that if the mutated form of some specific genes is inherited, the risk to suffer from colorectal cancer reaches approximately 100%. At this time, not all the responsible genes have been identified.
When can I suspect that my family may be affected
You can suspect colorectal cancer when several family members have suffered from this specific type of cancer or other types of cancer, mainly endometrial cancer Also, when there have been cases of young family members (under 50) diagnosed with cancer.
What do I have to do if I have relatives with colorectal cancer or other types of cancer?
You should seek help from your specialist, who will suggest the possible strategies to follow according to your particular risk and your age, referring you to have a genetic consultation if a case of familial syndrome is suspected.
Genetic counselling is a personalised evaluation carried out to determine the likelihood of developing a hereditary syndrome, in this case, colorectal cancer. The patient will be given the appropriate recommendations and if deemed applicable, genetic testing will be ordered to help establish whether the mutation affecting the family has been inherited.
Yes. Even though at this time we do not know all the genes that are involved in hereditary colorectal cancer, if a mutation is detected in one of the identified genes in an affected family member, the other members of the family will be able to be tested to see if such mutation has been inherited. This will enable us to find out the high risk of developing colorectal cancer or other types of cancers related to colorectal cancer.
Are these tests reliable?
If we are able to detect a mutation in an affected family member, all the other members will have to be tested by means of a simple test. Those who have not inherited the mutation will have the same risk as the rest of the population to develop colorectal cancer and thus, it will not be necessary to do any screening until they are 50, just as with the rest of the population with no symptoms Those individuals who have in fact inherited the mutation will have to follow the established guidelines to avoid the development of the cancer.
The most important family syndromes are Lynch´s syndrome, also known as non-polyposic colorectal cancer or without polyps, and familial adenomatous polyposis, characterised by the presence of a large number of polyps throughout the entire length of the colon.
Colorectal cancer is one of the most preventable cancers due to its generally slow growth and the significant knowledge acquired on familial syndromes. In all cases, the most important is to know what guidelines to follow and what needs to be done in each particular case.
Genetic Syndromes
Author: Dr. Maria Teresa Solé Pujol
A syndrome refers to an entire set of malformation or abnormalities that are observed in an individual and that affect different structures or organs of the body, all originated by a common cause.
A syndrome associated with colorectal cancer is the set of malformations or abnormalities that share the same aetiology and that can affect different structures of our body, among these the colon and the rectum.
You should see a geneticist to assess the syndrome and, once diagnosis is established, the geneticist will give you genetic counselling.
A session in which the affected individual (s) discusses with the geneticist physician the study, diagnosis, prognosis and prevention of the syndrome and future complications.
Prevention can be carried out prenatally (before the individual is born) or postnatally, after birth, to prevent future complications of the disease.
Because one of the progenitors has the mutated gene that is transmitted to the offspring.
Through the ovum (female) or the spermatozoon (male) at the time of fertilisation.
Remember that males have 46 chromosomes, grouped into 23 pairs, and that chromosomes are like our cookbook recipes….. let´s make a heart …. a kidney ready…….. etc.
From time to time, the recipes are wrong and the organs or tissues that come out based on their information are also wrong. The failure can become apparent during the prenatal period (before birth) or later on in life during the postnatal period (after birth).
It depends on each syndrome, but many of the genes involved in colorectal cancer have an autosomal dominant heredity.
Follow up protocol for colorectal carcinoma
Patients with colorectal cancer (CRC) in stage I will be followed up to detect the appearance of a second tumour or polyps with colonoscopy every 3 to 5 years.
In patients with a colorectal cancer in stage II or II, the follow up will include anamnesis, physical exploration, tumoral markers in blood (CEA), abdominal ultrasound and lower digestive endoscopy. The idoneity to perform an abdominopelvic tomography (CAT) in patients with a tumour of the rectum should be assessed.
If the preoperative exploration was incomplete, a new colonoscopy should be performed in the postoperative period.
The endoscopic exploration of the thick intestine, in case it was normal, will be performed every 3 years. As an alternative, in patients that do not tolerate this exploration, a proctoscopy and opaque enema will be done instead.
After the 5th year, the follow up will be done basically to detect metachronic cancer of the colon (later on in time).
Patients with colorectal cancer (CRC) in stage I will be followed up to detect the appearance of a second tumour or polyps with colonoscopy every 3 to 5 years.
In patients with a colorectal cancer in stage II o II, the follow up will include anamnesis, physical exploration, tumoral markers in blood (CEA), abdominal ultrasound and lower digestive endoscopy. The idoneity to perform an abdominopelvic tomography (CAT) in patients with a tumour of the rectum should be assessed.
If the preoperative exploration was incomplete, a new colonoscopy should be performed in the postoperative period.
The endoscopic exploration of the thick intestine, in case it was normal, will be performed every 3 years. As an alternative, in patients that do not tolerate this exploration, a proctoscopy and opaque enema will be done instead.
After the 5th year, the follow up will be done basically to detect metachronic cancer of the colon (later on in time).
How can we prevent colorectal cancer?
Primary prevention modifies the causes, making decisions that are the responsibility of Public Health. The objective of primary prevention is to decrease the incidence of colorectal cancer, both in the general population and in risk groups (relatives suffering from the disease, etc.).
Remember...
Our digestive system is a complex, extremely well fitted machine that needs to be cared for. Despite its complexity, our digestive system requires a certain routine to function better This means to eat properly and at the same time each day, to follow a balanced diet, to go to the toilet at regular times and on a daily basis, etc.
In general, the more we stick to a routine, the better off our digestive system will function
The ideal diet is a balanced, Mediterranean style diet. A low fat diet that is rich in vegetables and fruits improved the functioning of the intestine and prevents the formation and growth of digestive tumours such as colon cancer.
Moderate physical exercise improves intestinal function, favouring digestion and emptying of the bowels, preventing in this way the development of functional pathologies (irritable intestine syndrome, etc.) and organic functions (inflammatory disease, tumours, etc.).
Quit smoking. Tobacco has an influence on the formation of many tipes of cancer. It also plays a role in the development of cancer of the oesophagus, stomach or colon. For example, in cancer of the colon, men who are smokers have a 34% more possibility to develop this type of cancer and smoker females a 43%.
