Introduction
Human papillomavirus (HPV) is a relatively common infection that can be passed on during unprotected intercourse. It can cause a variety of anal cancers. HPV is not a single virus; more than 150 strains of HPV have been discovered. Some strains of HPV are harmless, while others cause anal and genital warts, and still, others can cause anal and cervical cancer. The types of HPV known as HPV16 and HPV18 are most likely to cause cancer. It primarily affects individuals with lower immunity, such as AIDS (acquired immunodeficiency syndrome) patients.
How Does the Spread of HPV Take Place?
HPV is spread through sexual activity that involves skin-to-skin or skin-to-mucosal contact, including vaginal, anal, and oral sex. It is prevalent in the young and sexually active population.
How HIV and Anal Cancer Are Related?
Human immunodeficiency virus (HIV) can affect every system of the body. It can lower the body's immunity by decreasing its defensive cell (CD4) count. In HIV, when immunity is lowered, it increases the risk of other infections in the body due to the body's lower reparative mechanisms. The HPV virus can cause severe diseases in HIV patients, including anal cancer. Therefore, HIV patients are at greater risk of developing anal lesions and anal cancer. On the other hand, HPV can also cause these lesions in non-HIV patients.
What Are the Symptoms Associated With Anal Cancer Caused by HPV?
Anal cancer can cause symptoms such as:
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Bleeding,
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Pain.
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Discomfort.
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Itching.
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Minor lumps.
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Ulcers on or inside the anus.
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Discharge.
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Bowel control problems.
People with low or high-grade AIN (anal intraepithelial lesion) frequently have no symptoms. However, it can occasionally induce symptoms comparable to anal cancer. Common health issues such as hemorrhoids can generate similar symptoms. Therefore, it is worthwhile to have them checked by a sexual health doctor or physician.
Who Is at Risk of the Development of Anal Cancer?
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Anal cancer is uncommon in the general population, but rates are significantly higher among HIV patients and others with immuno-compromised systems.
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People who have had receptive anal intercourse, who had multiple sexual partners, or who have had genital warts are more likely to be infected with HPV infections. This is because it increases the likelihood of severe anal cancer. However, high-grade AIN and anal cancer can also develop in people who have never had anal sex or HIV.
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Smoking increases cell mutation (aberrant alterations). Quitting smoking significantly lowers the risk of developing anal cancer and may help prevent it from advancing to cancer.
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As age increases, the chances of developing high-grade AIN and anal cancer increase due to the lowering of immunity.
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Women who previously showed abnormal cervical screening findings are more likely to develop anal cancer than other women. This is because HPV can travel between the genitals and the anus.
How to Make a Diagnosis of Anal Cancer in HIV Patients?
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As listed above, a rectal examination is the first step if a person shows any symptoms or related symptoms of anal cancer. The doctor will conduct a rectal examination by inserting a lubricated, gloved finger into the anal passage to feel lumps or swellings.
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Anal smear tests are used in some clinics to screen for AIN. A tiny swab is used to collect cells, suspended in fluid, stained, and studied under a microscope (cytology).
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Anoscopy is an alternative approach for detecting AIN. The results are more accurate in HIV patients than in the smear test. A small magnification instrument is slid into the anus to inspect the anal canal visually. This should only take a few minutes and be painless. A biopsy (the tissue sample collection) will be collected during the anoscopy. To minimize discomfort, little tissue samples are extracted under local anesthesia. These cells will then be inspected under a microscope in a procedure known as histology to determine whether they are regular, aberrant, or malignant cells.
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Proctoscopy is similar to anoscopy but can also inspect the rectum.
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In anal cancer, a person will need further scans to locate the position of cancer. These include a CT (computed tomography) scan and MRI (magnetic resonance imaging).
How Are Patients With Precancerous Anal Lesions Treated?
HIV patients require HAART (highly active antiretroviral therapy) for their survival. HAART therapy lessens the impact of immune system damage caused by HIV infection. Concurrent treatment with HAART and anticancer therapy is becoming more widespread as HAART permits HIV-infected populations to live longer. Concurrent use of HAART and chemotherapy is acceptable and not associated with life-threatening toxic consequences. There is no requirement for cancer treatment if a person has low-grade AIN. However, a patient is advised to have cancer screening after six or twelve months. If a patient has severe AIN, then one of the following treatments is useful:
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Surgery is used to eliminate lesions that cover a small area.
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A doctor gives a cream to apply on the anal lesions for three or four months. This works best for large areas of AIN, particularly on the skin's surface.
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Various procedures can be employed to destroy the damaged areas, such as:
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Electrocautery uses electrical heat to cut lesions with the help of a specific instrument.
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Laser ablation is lesion excision with the help of a laser.
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Infrared coagulation uses infrared radiation to remove anal lesions.
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Cryotherapy is the excision of the lesion with the help of low temperature.
None of these therapies has a 100 % success rate, and in many cases, the condition recurs. This could be because the treatments fail to eliminate the underlying HPV infection. In addition, the therapies may also cause adverse side effects (skin irritation, pain, and bleeding). For these reasons, some clinicians take a 'watch and wait' stance in individuals with severe AIN. This entails regular monitoring to ensure that the condition does not worsen.
How Are Chemotherapy and Radiotherapy Useful for Precancerous Anal Lesions?
In anal cancer, the recommended treatment is chemoradiotherapy, a mix of chemotherapy and radiotherapy administered over five weeks. Chemotherapy employs powerful medications to attack cancer cells and prevent them from spreading. Chemoradiotherapy is usually successful. However, it occasionally results in long-term problems, such as bladder, bowels, and sexual dysfunction. Radiotherapy uses radiation beams to eliminate cancer cells in a specific region.
Both chemotherapy and radiotherapy depress the immune system, which can lead to a considerable decrease in the CD4 count (the body's defense cells). Therefore, a patient should use medications to help avoid opportunistic infections (this is known as prophylaxis). After cancer therapy, the CD4 cell levels may be monitored more frequently than usual. Surgery may be employed if chemotherapy and radiotherapy do not entirely eradicate cancer or if symptoms have returned. In HIV-infected patients with anal cancer, the CD4 count should be closely monitored.
What Is the Issue Associated With Anal Cancer Treatment in HIV Patients?
Radiation to the bone marrow (where blood cells are produced) results in myelosuppression (depression of the bone marrow, resulting in decreased blood cells). It may be severe in individuals with anal cancer because the main supply is also radiated. The CD4 T-cell count, in particular, may decline even further and not return quickly to pretreatment levels. The guidelines for preventing opportunistic infections in HIV patients consider risk, history of exposure, and the immune system's condition. The guidelines for preventing infections in cancer patients are based on the severity and duration of neutropenia (decreased white blood cell count), a significant risk factor for infection.
What Is the Prevention for Anal Cancer in HIV Patients?
HPV infection causes cervical cancer, so administering the prophylactic HPV vaccine before the commencement of sexual activity is the primary preventive method for cervical cancer prevention. A similar strategy can be applied as the primary preventive method for anal cancer.
Conclusion
People living with HIV are much more likely to develop high-grade AIN or anal cancer than others. HIV infection affects the immune system and impairs the body’s ability to protect itself from HPV infection. Taking HIV medication and having a high CD4 count help guard against AIN and anal cancer. Anal cancer can occur in those on effective HIV medication. An early diagnosis and prompt treatment from the physician, radiologist, and oncologist jointly is necessary. HIV and non-HIV patients should consult a doctor as soon as they suspect symptoms.
