What is the anus?
The anus is the opening at the end of the digestive tract through which feces (waste matter) is expelled from the body. When food is digested in the small and large intestines, the remaining waste material is transported to the rectum, where it is stored until it is eliminated through the anus.
Anus is located at the end of the rectum and is surrounded by two sets of muscles called the anal sphincters, which help to control the release of feces. The anus is also a sensitive area that can be involved in sexual pleasure and is an erogenous zone for some people. It is an important part of the body’s excretory system and plays a crucial role in maintaining overall health and hygiene.
What is Anal Cancer?
Anal cancer is a type of cancer that affects the cells of the anus, which is the opening at the end of the digestive tract through which stool passes out of the body. Anal cancer usually starts in the cells of the lining of the anal canal and can spread to other parts of the body if left untreated.
The main cause of anal cancer is the human papillomavirus (HPV), which is a sexually transmitted infection that can lead to changes in the cells of the anus and increase the risk of cancer. Other risk factors include a weakened immune system, smoking, and a history of other cancers.
Types of Anal Cancer
There are several types of anal cancer based on the type of cells that are affected. The most common types of anal cancer include –
Squamous cell carcinoma
This type of anal cancer starts in the thin, flat cells lining the anal canal and accounts for about 80% of all anal cancers.
Cloacogenic carcinoma
This accounts for about 25% of all anal cancers. Cloacogenic cell cancer likely starts from cells that are similar to squamous cell cancer, and it is treated similarly.
Adenocarcinoma
This type of anal cancer starts in the glandular cells of the anal canal and accounts for about 10-20% of all anal cancers.
Basal cell carcinoma
This is a rare type of anal cancer that starts in the basal cells lining the anal canal.
Melanoma
This is a rare type of anal cancer that starts in the pigment-producing cells of the skin around the anus.
Risk Factors of Anal Cancer
There are several risk factors that can increase the likelihood of developing anal cancer. These include:
Human papillomavirus (HPV) infection
HPV is the main risk factor for anal cancer. The virus is transmitted through sexual contact, and certain strains of HPV are more strongly linked to the development of anal cancer.
Weakened immune system
People with weakened immune systems, such as those living with HIV/AIDS or those who have had an organ transplant, are at higher risk of developing anal cancer.
Smoking
Smoking can increase the risk of many types of cancer, including anal cancer.
Age
Anal cancer is more common in older adults, with the majority of cases occurring in people over the age of 50.
Personal history of cancer
People who have had certain types of cancer, such as cervical or vaginal cancer, are at a higher risk of developing anal cancer.
Chronic inflammation of the anus or rectum
Chronic inflammation of the anus or rectum, such as from inflammatory bowel disease or fistulas, may increase the risk of developing anal cancer.
It is important to note that having one or more of these risk factors does not mean that a person will develop anal cancer, and many people with anal cancer have no known risk factors. However, knowing about these risk factors can help individuals take steps to reduce their risk of developing anal cancer.
Symptoms of Anal Cancer
The symptoms of anal cancer can vary, and some people with early-stage anal cancer may not have any symptoms. However, some common symptoms of anal cancer include –
- Bleeding occurs in 50% of patients
- Pain in 40% of patients
- Sensation of a mass in 25% of patients
- Pruritus in 15%
It is important to note that about 25% of patients do not show any symptoms.
Diagnoses of Anal Cancer
The diagnosis of anal cancer typically involves a combination of medical history, physical examination, and tests to evaluate the anus and surrounding tissues. These tests may include –
Physical examination:
This should include digital anorectal examination, anoscopy, proctoscopy, EUS if available, and palpation of inguinal lymph nodes. The anorectal examination may have to be performed under sedation or general anaesthesia in patients with severe pain and anal spasm.
Biopsy:
An incisional biopsy is necessary and preferable to confirm the diagnosis. Excisional biopsy should be avoided. Suspicious inguinal lymph nodes should undergo a biopsy to differentiate inflammatory from metastatic disease. Needle aspiration of these nodes may establish the diagnosis; if aspiration is negative, a surgical biopsy should be performed.
Staging evaluation:
This should include physical examination, chest radiograph, and LFT. Pelvic CT and EUS of the anal canal may be useful. MRI and PET/CT scans are increasingly being utilized to document the extent of disease. HIV testing is appropriate when warranted by individual patient risk factors.
If anal cancer is diagnosed, further tests may be needed to determine the stage of cancer and whether it has spread to other parts of the body. This information is important in determining the most appropriate treatment options.
Preventions and Treatments for Anal Cancer
Preventions to be considered are as follows
There are several measures that can help reduce the risk of developing anal cancer –
- Get vaccinated: The HPV vaccine can help prevent infection with certain strains of the virus that are linked to anal cancer.
- Treat underlying conditions: Treating underlying conditions, such as HPV infection or inflammatory bowel disease, can reduce the risk of developing anal cancer.
- Stop smoking: Quitting smoking can reduce the risk of many types of cancer, including anal cancer.
- Maintain a healthy diet and exercise regularly: A healthy diet and regular exercise can help maintain a healthy weight, which can reduce the risk of many types of cancer.
- Get regular medical check-ups: Regular check-ups with a healthcare provider can help detect any abnormalities in the anal or rectal area early when treatment is most effective.
- Practice good hygiene: Keeping the anal and genital areas clean and dry can help prevent infection and irritation.
Treatments required for Anal Cancer
The treatment for anal cancer depends on the stage of cancer, the location and size of the tumour, and the person’s overall health. The most common treatments for anal cancer include –
This is the primary treatment of choice for anal carcinoma. This combination resulted in higher rates of both local control and survival (82%) and preserved anal function when compared with surgery. The administration of high-dose RT reduced the incidence of persistent carcinoma and eliminated the need for surgical lymphadenectomy. The radiation dose, the number of chemotherapy cycles required to improve the local control rate, and the role (if any) of invasive restaging after completion of therapy remain controversial.
Wide, full-thickness excision is sufficient treatment for discrete, superficial, anal margin tumours and results in an 80% 5-year survival rate unless the tumour is large and deep. AP resection of the anorectum as the exclusive treatment for anal canal tumours and large anal margin tumours results in only a 55% 5-year survival rate.
Immunotherapy is a type of treatment that uses the body’s own immune system to fight cancer. It may be used in combination with other treatments, such as chemotherapy or radiation therapy.
Denvax Immunotherapy: Denvax is a treatment known as cancer immunotherapy. It boosts the immune system to fight against cancer, mostly solid tumours. Denvax is targeted therapy and comes under the 4th modality of cancer treatment called cancer Immunotherapy.
Dendritic cells are cells of the immune system that help in the fight against cancer. Denvax treatment is customized dendritic cell-based cancer immunotherapy. Denvax shows the most promise at preventing a recurrence of cancer after surgery, chemotherapy or radiation because the immune system will need to recognize and attack a smaller number of cancer cells.
References:
- Manual of Clinical Oncology by Bartosz Chmeilowski and Mary Territo
- cancer.net
What is the anus?
The anus is the opening at the end of the digestive tract through which feces (waste matter) is expelled from the body. When food is digested in the small and large intestines, the remaining waste material is transported to the rectum, where it is stored until it is eliminated through the anus.
Anus is located at the end of the rectum and is surrounded by two sets of muscles called the anal sphincters, which help to control the release of feces. The anus is also a sensitive area that can be involved in sexual pleasure and is an erogenous zone for some people. It is an important part of the body’s excretory system and plays a crucial role in maintaining overall health and hygiene.
What is Anal Cancer?
Anal cancer is a type of cancer that affects the cells of the anus, which is the opening at the end of the digestive tract through which stool passes out of the body. Anal cancer usually starts in the cells of the lining of the anal canal and can spread to other parts of the body if left untreated.
The main cause of anal cancer is the human papillomavirus (HPV), which is a sexually transmitted infection that can lead to changes in the cells of the anus and increase the risk of cancer. Other risk factors include a weakened immune system, smoking, and a history of other cancers.
Types of Anal Cancer
There are several types of anal cancer based on the type of cells that are affected. The most common types of anal cancer include –
Squamous cell carcinoma
This type of anal cancer starts in the thin, flat cells lining the anal canal and accounts for about 80% of all anal cancers.
Cloacogenic carcinoma
This accounts for about 25% of all anal cancers. Cloacogenic cell cancer likely starts from cells that are similar to squamous cell cancer, and it is treated similarly.
Adenocarcinoma
This type of anal cancer starts in the glandular cells of the anal canal and accounts for about 10-20% of all anal cancers.
Basal cell carcinoma
This is a rare type of anal cancer that starts in the basal cells lining the anal canal.
Melanoma
This is a rare type of anal cancer that starts in the pigment-producing cells of the skin around the anus.
Risk Factors of Anal Cancer
There are several risk factors that can increase the likelihood of developing anal cancer. These include:
Human papillomavirus (HPV) infection
HPV is the main risk factor for anal cancer. The virus is transmitted through sexual contact, and certain strains of HPV are more strongly linked to the development of anal cancer.
Weakened immune system
People with weakened immune systems, such as those living with HIV/AIDS or those who have had an organ transplant, are at higher risk of developing anal cancer.
Smoking
Smoking can increase the risk of many types of cancer, including anal cancer.
Age
Anal cancer is more common in older adults, with the majority of cases occurring in people over the age of 50.
Personal history of cancer
People who have had certain types of cancer, such as cervical or vaginal cancer, are at a higher risk of developing anal cancer.
Chronic inflammation of the anus or rectum
Chronic inflammation of the anus or rectum, such as from inflammatory bowel disease or fistulas, may increase the risk of developing anal cancer.
It is important to note that having one or more of these risk factors does not mean that a person will develop anal cancer, and many people with anal cancer have no known risk factors. However, knowing about these risk factors can help individuals take steps to reduce their risk of developing anal cancer.
Symptoms of Anal Cancer
The symptoms of anal cancer can vary, and some people with early-stage anal cancer may not have any symptoms. However, some common symptoms of anal cancer include –
- Bleeding occurs in 50% of patients
- Pain in 40% of patients
- Sensation of a mass in 25% of patients
- Pruritus in 15%
It is important to note that about 25% of patients do not show any symptoms.
Diagnoses of Anal Cancer
The diagnosis of anal cancer typically involves a combination of medical history, physical examination, and tests to evaluate the anus and surrounding tissues. These tests may include –
Physical examination:
This should include digital anorectal examination, anoscopy, proctoscopy, EUS if available, and palpation of inguinal lymph nodes. The anorectal examination may have to be performed under sedation or general anaesthesia in patients with severe pain and anal spasm.
Biopsy:
An incisional biopsy is necessary and preferable to confirm the diagnosis. Excisional biopsy should be avoided. Suspicious inguinal lymph nodes should undergo a biopsy to differentiate inflammatory from metastatic disease. Needle aspiration of these nodes may establish the diagnosis; if aspiration is negative, a surgical biopsy should be performed.
Staging evaluation:
This should include physical examination, chest radiograph, and LFT. Pelvic CT and EUS of the anal canal may be useful. MRI and PET/CT scans are increasingly being utilized to document the extent of disease. HIV testing is appropriate when warranted by individual patient risk factors.
If anal cancer is diagnosed, further tests may be needed to determine the stage of cancer and whether it has spread to other parts of the body. This information is important in determining the most appropriate treatment options.
Preventions and Treatments for Anal Cancer
Preventions to be considered are as follows
There are several measures that can help reduce the risk of developing anal cancer –
- Get vaccinated: The HPV vaccine can help prevent infection with certain strains of the virus that are linked to anal cancer.
- Treat underlying conditions: Treating underlying conditions, such as HPV infection or inflammatory bowel disease, can reduce the risk of developing anal cancer.
- Stop smoking: Quitting smoking can reduce the risk of many types of cancer, including anal cancer.
- Maintain a healthy diet and exercise regularly: A healthy diet and regular exercise can help maintain a healthy weight, which can reduce the risk of many types of cancer.
- Get regular medical check-ups: Regular check-ups with a healthcare provider can help detect any abnormalities in the anal or rectal area early when treatment is most effective.
- Practice good hygiene: Keeping the anal and genital areas clean and dry can help prevent infection and irritation.
Treatments required for Anal Cancer
The treatment for anal cancer depends on the stage of cancer, the location and size of the tumour, and the person’s overall health. The most common treatments for anal cancer include –
This is the primary treatment of choice for anal carcinoma. This combination resulted in higher rates of both local control and survival (82%) and preserved anal function when compared with surgery. The administration of high-dose RT reduced the incidence of persistent carcinoma and eliminated the need for surgical lymphadenectomy. The radiation dose, the number of chemotherapy cycles required to improve the local control rate, and the role (if any) of invasive restaging after completion of therapy remain controversial.
Wide, full-thickness excision is sufficient treatment for discrete, superficial, anal margin tumours and results in an 80% 5-year survival rate unless the tumour is large and deep. AP resection of the anorectum as the exclusive treatment for anal canal tumours and large anal margin tumours results in only a 55% 5-year survival rate.
Immunotherapy is a type of treatment that uses the body’s own immune system to fight cancer. It may be used in combination with other treatments, such as chemotherapy or radiation therapy.
Denvax Immunotherapy: Denvax is a treatment known as cancer immunotherapy. It boosts the immune system to fight against cancer, mostly solid tumours. Denvax is targeted therapy and comes under the 4th modality of cancer treatment called cancer Immunotherapy.
Dendritic cells are cells of the immune system that help in the fight against cancer. Denvax treatment is customized dendritic cell-based cancer immunotherapy. Denvax shows the most promise at preventing a recurrence of cancer after surgery, chemotherapy or radiation because the immune system will need to recognize and attack a smaller number of cancer cells.
References:
- Manual of Clinical Oncology by Bartosz Chmeilowski and Mary Territo
- cancer.net
