Anal Cancer – Risk Factors, Symptoms, Prognosis And Treatment

Anal Cancer

Anal cancer is a disease in which malignant cell (cancer) develop in the tissues of the anal region. The anus is the terminal portion ofthe large intestine after the rectum through which stool is eliminated from the body. The anus is formed partly from the external skin and partly from the intestine. Two muscle open and close the anus to allow faeces to be removed from the body. The anal canal (portion between the rectum and anus), has a length of about 1.5 inch (3.75 cm). The skin around the anus is called the perianal area. Tumors in this area are skin cancers not anal cancers. Infection with human papilomatos virus (HPV) is considered to be a risk factor for anal cancer.

Colon

The Risk factors for anal cancer are:

• Age over 50 years
• Presence of human papilomatos virus infection (HPV)
• Multiple sex partners
• Anal intercourse
• The frequent presence of erythema (redness), inflammation and pruritus (itching)
• Anal fistulas (abnormal connection between two cavities
• Smoking

Symptoms

Possible signs of anal cancer is bleeding from the anus or rectum or a lump near the anus. There are however other reasons for such accusations, besides anal cancer.

Consult a doctor if you experience any of these signs:

• Bleeding from the anus or rectum
• Pain or pressure in the anus
• Itching or discharge from the anus
• A swelling near the anus
• Stool changes (diarrhea or constipation).

Investigations

Tests that examine the rectum and anus are used to find and diagnose anal cancer.

• Physical examination and full patient history: generally physical examination is searching for different signs of disease, such as lumps or other unusual aspects, also diseases that had previously received medication, the lifestyle aspects and not last the eating habits
• Digital rectal examination (TR) is an exam of the anus and rectum, the doctor or a nurse, using surgical gloves,introduces a previously lubricated finger in the lower rectum to look for any swelling sings or unusual aspects.
• Anoscope: represents an examination of the anus and rectum in its lower portion using a short tube with a dot at the end called anoscope
• Biopsy: consist in the removing  of cells or small pieces of tissues that are studied under a microscope by a pathologist to look for signs of cancer or precancerous lessions

Anal Cancer Examination

Prognosis

There are certain factors that can affect the prognosis (in other words the chances of recovery) and treatment options:

• Tumor size
• Exact localization of the tumor in the anus
• If the cancer has spread to lymph nodes or

Treatment options depend on the following factors:

• Stage of cancer
• Tumor in anus
• If the patient is infected or not with human papilomatos virus (HPV)
• If cancer is still present after the initial treatment or is it a recurrence (initially cured but came back).

Treatment
For patients who are suffering from anal cancer there are several treatment options available. Some treatments are standard while others are only during the testing period (clinical trials). Before starting treatment, the patient may think if he wants to be part of such a clinical trial. If the clinical trial proves that a new and better treatment is superior to the standard therapy, the new treatment is made standard treatment.

Choosing the most appropriate treatment is a decision that ideally should be taken by the patient and his family after consulting the doctor.

Currently use three types of standard treatment:

1. Radiation. Radiation therapy is used for treating cancer with the aid of  high energy X-rays or other radiation to get rid of cancer cells. There are two types of radiation. External radiation therapy uses a device located outside of the body to send radiation toward the cancer area. Internal radiation therapy uses radioactive substances introduced by needles, implants, wires or catheters placed in / or near the tumor. The type of radiation applied depends on the type and stage of cancer.
   

   Radiation Therapy

2. Chemotherapy. Chemotherapy uses drugs that prevent cancer cells to grow, either by actual killing them or by stopping their multiplication. After the intravenous injection, the drugs enter the bloodstream and travel throughout the body. This is systemic chemotherapy. When chemotherapy is placed directly into the spinal column, an organ or a cavity such as the abdomen, the drug has an effect only on cancer cells in that certain area. This is called regional chemotherapy.
3. Surgery. Several types of surgical interventions are available: local resection: a surgical procedure in which the tumor is removed from the anus with an area of surrounding healthy tissue. This kind of local resection can be achieved if the tumor is small and has not spread. This kind of procedure may save the sphincter muscles  this method can be used especially for tumors that develop in the lower anus. Low resection: a surgical procedure in which the anus, rectum and a variable part of the sigmoid colon are resected (removed) through an incision made in the abdomen. Afterwards the intestine is sutured with one end to the external skin of the abdomen (stoma), leaving a communication, through which the faeces can be collected in a bag outside the body.

Anal Cancer Stoma

The presence of HPV virus can affect anal cancer treatment. Patients infected with human immunodeficiency virus (HIV) who already have a poor immune system are further aggravated by the use of cancer treatments. Therefore, patients who have concomitant HIV infection and anal cancer are treated with chemotherapy and radiotherapy doses lower than patients without HIV.

Other treatments are in clinical trials stage. An example of such treatment are some medicines that aim making cancer cells more sensitive to radiotherapy. By combining radiotherapy with the administration of these kind of drugs more cancer cells will pe affected by the treatment in a shorter time, reducing the side effects of radiotherapy.