A diagnosis of anal cancer can be overwhelming, especially if you’re unsure what to expect. This page explains how anal cancer is diagnosed, including the most common tests and examinations used by healthcare professionals. We also outline how doctors determine whether the cancer has spread, when to seek testing, risk factors, treatment options, and where to find support.
Key Takeaways
- Anal cancer is diagnosed using a combination of physical examinations, imaging tests, and biopsies to confirm whether cancer is present and determine its stage.
- Diagnostic tests may include anoscopy, endoscopy, CT scans, MRI scans, PET scans, and biopsies to assess the size of the tumour and whether it has spread.
- Understanding the stage of anal cancer helps healthcare teams develop the most appropriate treatment plan and provide a clearer outlook for patients.
How is Anal Cancer Diagnosed?
Anal cancer is rare, and its symptoms are often mistaken for less serious conditions like hemorrhoids or anal fissures. Diagnosis typically begins with a visit to your PCP-Primary Care Physician GP, who may refer you to a specialist if your symptoms warrant further investigation.
Physical Examination
Your doctor may start by inspecting the anal area for any visible abnormalities, swelling, or lesions.
Medical History
The doctor will also take a full medical history, including any previous conditions, family history of cancer, sexual health history, and any risk factors such as HPV or smoking.
Digital Anal Rectal Examination (DRE)
A DARE involves the doctor gently inserting a gloved, lubricated finger into the anus to feel for lumps, swelling, or other irregularities in the anal canal and rectum.
Anoscopy
An anoscope is a short, rigid tube that allows doctors to see inside the anal canal more clearly. This procedure helps identify abnormal tissue or lesions.
Rigid Proctosigmoidoscopy
This test uses a rigid scope to examine the lower rectum and part of the sigmoid colon. It helps doctors assess how far any abnormality might extend.
Endoscopy
Flexible endoscopy (usually a sigmoidoscopy or colonoscopy) provides a more extensive view of the lower gastrointestinal tract and may be used to rule out other causes of symptoms.
Blood Test
While not used to diagnose anal cancer directly, blood tests can provide useful information about your general health and whether you’re fit for further tests or treatment.
Biopsy
If a suspicious area is found, a biopsy may be taken. This involves removing a small sample of tissue for analysis under a microscope to confirm whether cancer cells are present.
Extent of Cancer if Found
If a biopsy confirms anal cancer, further tests help determine how advanced it is. This process is called staging.
Imaging Tests
Imaging helps show whether the cancer has spread to nearby lymph nodes or other organs.
Ultrasound
An endoanal or pelvic ultrasound may be used to examine the tumor and nearby lymph nodes, especially in early-stage cancer.
CT Scan
A CT (computed tomography) scan of the chest, abdomen and pelvis may be carried out to look for cancer spread.
MRI Scan
MRI (magnetic resonance imaging) provides detailed images of soft tissue and is often used to assess the size and local spread of the tumor, particularly into surrounding muscles or organs.
X-ray
X-rays may be used to check the lungs or other areas where cancer might have spread.
Fine Needle Aspiration (FNA)
If lymph nodes appear enlarged, a fine needle aspiration may be used to extract cells to check for cancer.
PET- CT Scan
A PET- CT combines two types of scans to detect active cancer cells throughout the body and is often used in more advanced cases or before treatment planning.
Signs You Should Get Tested
It’s important to speak to a doctor if you experience:
- Persistent anal pain or itching
- Bleeding from the anus or rectum
- A lump or mass near the anus
- Changes in bowel habits, such as persistent diarrhea or constipation
These symptoms do not always mean cancer, but they should be investigated by a medical professional.
Risk Factors
Factors that may increase your risk of anal cancer include:
- Infection with human papillomavirus (HPV), especially HPV-16
- Smoking
- A history of cervical, vulvar, or vaginal cancer
- A weakened immune system, such as in people with HIV
- Being over 50
- Anal intercourse, particularly with multiple partners
Treatment
If you’re diagnosed with anal cancer, treatment typically involves one or a combination of the following:
- Chemoradiotherapy (combined chemotherapy and radiotherapy), which is the most common treatment
- Surgery, usually reserved for cases where cancer remains or returns after initial treatment
- Supportive care to manage side effects and improve quality of life
Your treatment will depend on the stage and location of the cancer, your general health, and personal preferences.
FAQs
What are the common symptoms that prompt a doctor to consider anal cancer?
Anal bleeding, pain, itching, a lump or mass, or persistent changes in bowel habits may prompt a referral for further testing.
Is there a specific medical specialist who diagnoses anal cancer?
Yes. Colorectal surgeons, gastroenterologists, and oncologists typically conduct the necessary tests and confirm diagnosis.
Are there any screening tests for anal cancer?
Routine screening is not recommended for the general population, but high-risk individuals may receive anal Pap smears or high-resolution anoscopy.
What is a biopsy, and why is it done?
A biopsy removes a small sample of tissue from a suspicious area. It confirms whether cancer cells are present and helps guide treatment decisions.
What should I expect during a biopsy?
Biopsies are usually done under local anaesthetic. You may feel some pressure or mild discomfort. The procedure is typically quick and done in an outpatient setting.
How long does it take to get biopsy results?
Results are often available within one to two weeks, but it may vary depending on the hospital.
What happens if the biopsy confirms cancer?
You will have further tests to determine the stage of cancer, and your medical team will help you create a treatment plan.
Can anal cancer be mistaken for other conditions?
Yes. Symptoms often resemble those of hemorrhoids or fissures, so thorough medical investigation is crucial.
Is there anything I can do to reduce my risk?
Yes. HPV vaccination, smoking cessation, safer sex practices, and regular check-ups can help reduce your risk.
Need support?
Looking for someone to talk to about your anal cancer diagnosis? We are here to help. The Peer to Peer Support Program is a free service provided by the Anal Cancer Foundation that matches anal cancer thrivers (our word for survivors) and caregivers with thriver volunteers and caregiver volunteers.
A diagnosis of anal cancer can be overwhelming, especially if you’re unsure what to expect. This page explains how anal cancer is diagnosed, including the most common tests and examinations used by healthcare professionals. We also outline how doctors determine whether the cancer has spread, when to seek testing, risk factors, treatment options, and where to find support.
Key Takeaways
- Anal cancer is diagnosed using a combination of physical examinations, imaging tests, and biopsies to confirm whether cancer is present and determine its stage.
- Diagnostic tests may include anoscopy, endoscopy, CT scans, MRI scans, PET scans, and biopsies to assess the size of the tumour and whether it has spread.
- Understanding the stage of anal cancer helps healthcare teams develop the most appropriate treatment plan and provide a clearer outlook for patients.
How is Anal Cancer Diagnosed?
Anal cancer is rare, and its symptoms are often mistaken for less serious conditions like hemorrhoids or anal fissures. Diagnosis typically begins with a visit to your PCP-Primary Care Physician GP, who may refer you to a specialist if your symptoms warrant further investigation.
Physical Examination
Your doctor may start by inspecting the anal area for any visible abnormalities, swelling, or lesions.
Medical History
The doctor will also take a full medical history, including any previous conditions, family history of cancer, sexual health history, and any risk factors such as HPV or smoking.
Digital Anal Rectal Examination (DRE)
A DARE involves the doctor gently inserting a gloved, lubricated finger into the anus to feel for lumps, swelling, or other irregularities in the anal canal and rectum.
Anoscopy
An anoscope is a short, rigid tube that allows doctors to see inside the anal canal more clearly. This procedure helps identify abnormal tissue or lesions.
Rigid Proctosigmoidoscopy
This test uses a rigid scope to examine the lower rectum and part of the sigmoid colon. It helps doctors assess how far any abnormality might extend.
Endoscopy
Flexible endoscopy (usually a sigmoidoscopy or colonoscopy) provides a more extensive view of the lower gastrointestinal tract and may be used to rule out other causes of symptoms.
Blood Test
While not used to diagnose anal cancer directly, blood tests can provide useful information about your general health and whether you’re fit for further tests or treatment.
Biopsy
If a suspicious area is found, a biopsy may be taken. This involves removing a small sample of tissue for analysis under a microscope to confirm whether cancer cells are present.
Extent of Cancer if Found
If a biopsy confirms anal cancer, further tests help determine how advanced it is. This process is called staging.
Imaging Tests
Imaging helps show whether the cancer has spread to nearby lymph nodes or other organs.
Ultrasound
An endoanal or pelvic ultrasound may be used to examine the tumor and nearby lymph nodes, especially in early-stage cancer.
CT Scan
A CT (computed tomography) scan of the chest, abdomen and pelvis may be carried out to look for cancer spread.
MRI Scan
MRI (magnetic resonance imaging) provides detailed images of soft tissue and is often used to assess the size and local spread of the tumor, particularly into surrounding muscles or organs.
X-ray
X-rays may be used to check the lungs or other areas where cancer might have spread.
Fine Needle Aspiration (FNA)
If lymph nodes appear enlarged, a fine needle aspiration may be used to extract cells to check for cancer.
PET- CT Scan
A PET- CT combines two types of scans to detect active cancer cells throughout the body and is often used in more advanced cases or before treatment planning.
Signs You Should Get Tested
It’s important to speak to a doctor if you experience:
- Persistent anal pain or itching
- Bleeding from the anus or rectum
- A lump or mass near the anus
- Changes in bowel habits, such as persistent diarrhea or constipation
These symptoms do not always mean cancer, but they should be investigated by a medical professional.
Risk Factors
Factors that may increase your risk of anal cancer include:
- Infection with human papillomavirus (HPV), especially HPV-16
- Smoking
- A history of cervical, vulvar, or vaginal cancer
- A weakened immune system, such as in people with HIV
- Being over 50
- Anal intercourse, particularly with multiple partners
Treatment
If you’re diagnosed with anal cancer, treatment typically involves one or a combination of the following:
- Chemoradiotherapy (combined chemotherapy and radiotherapy), which is the most common treatment
- Surgery, usually reserved for cases where cancer remains or returns after initial treatment
- Supportive care to manage side effects and improve quality of life
Your treatment will depend on the stage and location of the cancer, your general health, and personal preferences.
FAQs
What are the common symptoms that prompt a doctor to consider anal cancer?
Symptoms that might lead a doctor to consider anal cancer include persistent anal pain, bleeding from the anus or rectum, changes in bowel habits, such as persistent diarrhea or constipation, and the presence of a lump or mass near the anus. Itching or discharge can also occur. These symptoms have many possible causes, so an examination is needed.
Is there a specific medical specialist who diagnoses anal cancer?
Typically, a colorectal surgeon, gastroenterologist, or oncologist may be involved in diagnosing anal cancer. These specialists have expertise in evaluating and treating conditions related to the anus and rectum.
Are there any screening tests for anal cancer?
There is no routine anal cancer screening program for everyone. Screening is recommended for certain higher-risk groups. It may include an examination and an anal swab to check for abnormal cells, sometimes with a high-risk HPV test. Abnormal results may lead to high-resolution anoscopy, a magnified examination with biopsies when needed.
US HIV guidance recommends starting screening at age 35 for men who have sex with men and transgender women with HIV, and at 45 for other people with HIV. Some people without HIV also qualify under specialist guidance. Screening should be linked to access to the follow-up examination and treatment.
Ask your clinician about your own risk and local services.
If you have symptoms, seek an assessment regardless of your age or screening schedule.
What is a biopsy, and why is it done?
A biopsy involves taking a small sample of tissue from an area that looks abnormal. A specialist examines it under a microscope to find out whether cancer cells are present and, if so, what type they are. This information confirms the diagnosis and helps guide treatment.
What should I expect during a biopsy?
For a small biopsy in a clinic, the area may be numbed with local anesthetic before a small tissue sample is removed. You may feel pressure or brief discomfort. Some biopsies need sedation or a general anesthetic in a hospital, depending on the location, size and pain of the area being examined.
Ask which procedure you will have, whether you need to prepare beforehand, what discomfort or bleeding to expect and when to call for help afterward.
How long does it take to get biopsy results?
Results are often available within a week or two, but the time varies between services and may be longer if extra tests are needed. Ask your clinic when to expect the result, how you will receive it and who to contact if you have not heard back.
What happens if the biopsy confirms cancer?
Your team may arrange scans and other tests to find out the cancer’s stage and plan treatment. For most stage I to III anal squamous cell cancers, the usual treatment is chemotherapy and radiation together. Surgery is used in selected situations. Other types of anal cancer may need a different approach. Your team will explain the options for your diagnosis.
Can anal cancer be mistaken for other conditions?
Yes. Anal cancer symptoms can be mistaken for haemorrhoids, anal fissures, which are small tears, or other noncancerous conditions. Persistent or unexplained symptoms need an examination, even if you have previously been told you have haemorrhoids.
Is there anything I can do to reduce my risk?
HPV vaccination, when you are eligible, and stopping smoking can lower your risk. Condoms and other barriers reduce HPV transmission but do not prevent it completely because HPV can affect uncovered skin.
For people in higher-risk groups, screening can find abnormal cells before cancer develops. Treating high-grade anal precancer has been shown to reduce anal cancer risk in people with HIV. Ask your clinician whether screening applies to you. Eating well and being active support your general health, but no diet guarantees that anal cancer will be prevented.
How do I tell my friends and family about my diagnosis?
Telling loved ones that you have cancer can be one of the most emotionally difficult moments after diagnosis. Read our guide on how to talk to friends and family about your cancer diagnosis.
Need support?
Looking for someone to talk to about your anal cancer diagnosis? We are here to help. The Peer to Peer Support Program is a free service provided by the Anal Cancer Foundation that matches anal cancer thrivers (our word for survivors) and caregivers with thriver volunteers and caregiver volunteers.
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