Caricnoma of the anus mainly develops in the anal canal (anal canal cancer), which connects the anus to the rectum.
Now, the anus is a part of our gastrointestinal tract and is the outlet from which excreta goes out of the body. For any reason, if an abnormal mass of cells gets formed near the anal, it leads to the formation of a tumor.
This anal tumor can be cancerous or not, depending on whether it is malignant. A malignant tumor gets converted into cancer, which can then spread to other parts of the body.
Depending on the origin of these cancerous cells, anal carcinoma can be divided into different types. This classification helps doctors understand what does anal cancer feel like and adopt an effective anal cancer diagnosis.
Speaking of how common is anal cancer, it is important to note that it is a rare type of cancer, and more common among older adults. The exact reason for the lower incidence of anal carcinoma is unknown.
Despite its rare occurrence, it can be fatal if it is not diagnosed early and treated on time. Thanks to modern treatment approaches, it is possible to treat anal carcinoma with positive health outcomes, and patients are able to lead a normal life after their treatment.
Anal dysplasia can be termed a precancerous condition that leads to the formation of lesions in or around the anal canal. Though anal dysplasia is not cancerous, it can transform into cancer by converting the normal anal cells into abnormal ones, leading to an anal tumor or cancer.
Anal dysplasia initiates in the mucosa, the anal canal's inner lining, and is caused by different variants of the human papillomavirus (HPV). Now, anal dysplasia may not always cause any symptoms. However, if it does, it may include an itchy anus or even a lump in the anus. Some people may even have warts in the anus, which are usually an HPV symptom and not an anal tumor.
In most cases, carcinoma of the anus is diagnosed in individuals aged between 55 and 64. The risk of anal carcinoma is low in those aged below 35.
Carcinoma of the anus is common among those with chronic HPV infection. In addition to this, compromised immunity also contributes to increased anal carcinoma risk.
If we talk to experts about who gets anal cancer, they say that those with unhealthy lifestyle habits and unusual sexual practices, such as anal intercourse, are more susceptible to anal malignancies.
Anal carcinoma originates from cells in the mucosa, the anal canal's inner lining. Essential ducts and glands can be found under the mucosa. In simple words, it can be said that this cancer starts either just inside or around the anal opening.
The anus, the most significant part of the digestive tract, is positioned at the end of the rectum. The perianal skin and the anal canal together form the anus. The following are the different parts of anus, where cancer can form:
The anal margin can be explained as a circle formed by skin tissues with a radius of 5 cm starting from the anal verge. In rare cases, anal carcinoma can form in the anal margin, which makes it one of the less common anal cancer types.
The anal canal is a 4-cm-long tube that is responsible for connecting the anus to the rectum. The link between the anal canal and rectum is known as the anorectal line. The anal sphincter, or ring-like muscles, surrounds it. In fact, anal canal cancer is the most common type of anal cancer type.
The transitional zone refers to the anal canal lying just above the pectinate line and extending from 1 to 2 cm. Rarely, anal carcinoma can also form in the transitional zone.
Carcinoma of the anus is classified into two major groups based on the region where it forms. These include anal canal cancer, i.e., cancer in the area lying above the anal verge, and cancer of the anal margin or perianal skin, i.e., the region lying below the anal verge.
The treatment for these anal cancer types depends on their location. However, in many cases, especially in cases of stage 4 anal cancer, the cancer may quickly spread from one area to another. This can make it a little difficult for doctors to determine the area where the cancer started.
Thus, depending on the anal cancer pain and the stage, doctors often recommend anal cancer treatment. The following are the different anal cancer types:
Carcinoma in situ refers to precancerous cells or early cancer cells. This anal tumor arises from the cells present on the anal canal's surface and can also be known as Bowen's disease.
As the name suggests, this type of anal carcinoma initiates in the squamous cells. These cells are present mainly in the anal canal and the anal margin. When these cells become cancerous, it can lead to anal canal cancer. This is one of the most common anal cancer types.
A small group of anal tumors are referred to as adenocarcinomas, and they form in the cells lining the anus' upper part. In addition, adenocarcinomas can also start in the glands lying under the anal mucosa, which are responsible for releasing secretions in the anus.
Skin cancer refers to cancerous growth in the cells comprising the skin of the anus. These can be divided into two types: basal cell carcinoma and melanoma.
As the name suggests, gastrointestinal stromal tumors are more common in the small intestine or stomach. It is, again, quite rare to find it in the anal region.
Basal cell carcinoma refers to a kind of skin cancer that can initiate and develop in the perianal skin. Usually, this kind of cancer develops mainly in the skin, which is highly exposed to the sun, and this makes basal cell carcinoma of the anus rare.
Melanoma refers to a type of cancer that forms in the cells present in the anus skin or anal lining, which is responsible for creating the brown pigment called melanin. Anal melanomas are rare.
Poorly differentiated neuroendocrine tumors are pretty uncommon in the anal area. It is difficult to distinguish these cells from healthy ones, as they look identical. These tumors are divided into two types: large-cell and small-cell. This differentiation is based on how these cells look under the microscope.
Anal lymphomas are uncommon. Lymphomas refer to cancers of the disease-fighting system of the human body.
It is highly recommended to see a doctor for any of the symptoms of anal canal cancer. These symptoms may include a lump in the anus, itching, pain in the anal region (which is referred to as anal cancer pain), or bleeding from the anus.
Even if the symptoms are mild, you should visit a doctor who will refer you to a surgeon to check for any anal cancer lumps or other signs.