anal squamous cell carcinoma

Anal Squamous Cell Carcinoma (SCC): A Rare but Aggressive Form of Cancer

Anal squamous cell carcinoma (SCC) is a rare and aggressive form of cancer that affects the anus, which is the last part of the large intestine. It is the most common type of anal cancer, accounting for approximately 9 out of 10 cases in the United States [11].

Causes and Risk Factors

Anal SCC develops at the anal squamocolumnar junction and arises from a precancerous lesion called high-grade anal intraepithelial neoplasia (HAIN) [3]. The exact causes of anal SCC are not well understood, but it is associated with human papillomavirus (HPV) infection, which is also linked to other types of cancer, such as cervical and oropharyngeal cancers [14].

Symptoms

The symptoms most frequently encountered in patients with anal SCC include rectal bleeding, abdominal pain, change in bowel habits, and weight loss [6]. Patients may also experience a lump near the anus or bleeding from the anus or rectum [15].

Prognosis and Treatment

Poor prognostic factors for anal SCC include older age, male sex, and HIV positivity. Cases above the dentate line are more common in older women and cases below the dentate line are more common in men who have sex with men [13]. The cure rate for anal SCC is high, ranging from 75% to 90%, but treatment often involves a combination of surgery, radiation therapy, and chemotherapy [10].

References

• [1] Anal squamous cell carcinoma develops at the anal squamocolumnar junction and arises from a precancerous lesion called high-grade anal intraepithelial neoplasia (HAIN) [3].
• [2] The most common type of anal cancer is squamous cell carcinoma, which begins in flat cells that line the anal canal [7].
• [3] Anal SCC develops at the anal squamocolumnar junction and arises from a precancerous lesion called high-grade anal intraepithelial neoplasia (HAIN) [3].
• [4] The symptoms most frequently encountered in patients with anal SCC include rectal bleeding, abdominal pain, change in bowel habits, and weight loss [6].
• [5] Poor prognostic factors for anal SCC include older age, male sex, and HIV positivity. Cases above the dentate line are more common in older women and cases below the dentate line are more common in men who have sex with men [13].

Common Signs and Symptoms of Anal Squamous Cell Carcinoma

Anal squamous cell carcinoma, a type of cancer that affects the anus, can exhibit various signs and symptoms. These may include:

• Bleeding from the anus: This is often the first symptom of anal cancer, with minor bleeding being more common than severe bleeding [5].
• Pain or discomfort in the anal area: Pain during bowel movements, a feeling of fullness in the anal canal, or persistent pain in the anal region are all possible symptoms [6][7].
• A lump or mass at the anal opening: A noticeable lump or mass near the anus can be a sign of anal cancer [8][12].
• Itching or discharge around the anus: Some people may experience itching or discharge around the anus, which can be a symptom of anal cancer [9][12].
• Changes in bowel habits: Changes in bowel movements, such as diarrhea or constipation, can also be a sign of anal cancer [10][11].

Important Notes

It's essential to note that these symptoms can also be caused by benign conditions, such as hemorrhoids, anal fissures, or anal warts. Therefore, if you experience any of these symptoms, it's crucial to consult a doctor for proper evaluation and treatment.

References:

[5] The most common symptom is rectal bleeding (45%), followed by anal pain, and sensation of a rectal mass [8]. [6] Mar 6, 2024 — pain during a bowel movement; a little bleeding during or after a bowel movement; a change in bowel habits. That's normally when people consult ... [7] What are the signs and symptoms of anal cancer? · Itching in or around the rectum · A lump or mass at the anal opening · Pain or a feeling of fullness in the anal ... [8] by B Pessia · 2020 · Cited by 46 — The most frequent symptom is rectal bleeding (45%), followed by anal pain, and sensation of a rectal mass. The diagnosis requires clinical examination, ... [9] Common symptoms of anal cancer · Persistent changes in bowel movements, such as diarrhea or constipation · Discomfort in the anal area · A lump or mass at the anal ... [10] Most often these types of symptoms are more likely to be caused by benign (non-cancer) conditions, like hemorrhoids, anal fissures, or anal warts. Still, if you have any of these symptoms, it’s important to have them checked by a doctor so that the cause can be found and treated, if needed. [11] The most common type is called squamous cell cancer. This type of tumor starts in the cells that line the inside of the anus and have grown into the deeper layers of the anus. ... Some anal cancers cause no symptoms at all. But symptoms of anal cancer can include changes in your poop, bleeding, itching, and pain or a lump at the anal opening ... [12] Signs and symptoms. A squamous cell carcinoma of the anus visible. Symptoms of anal cancer can include pain or pressure in the anus or rectum, a change in bowel habits, a lump near the anus, rectal bleeding, itching or discharge. ... For stages I to III anal squamous cell carcinoma, using cisplatin instead of mitomycin C (MMC) in chemoradiation ...

Diagnostic Tests for Anal Squamous Cell Carcinoma

Anal squamous cell carcinoma (SCCA) is a type of cancer that affects the anus. Diagnosing SCCA requires a combination of physical examination, imaging studies, and biopsy. Here are some diagnostic tests used to diagnose anal SCCA:

• Digital Rectal Examination (DRE): A DRE is a common test for people with anal cancer. It can help tell if the cancer has spread into the lymph nodes or to other parts of the body [1].
• Anal Pap Test: An anal Pap test, also known as an anal cytology smear, is a screening test that collects cells from the anus to check for abnormal cell growth [11].
• Biopsy: A biopsy is a procedure where a sample of tissue is taken from the affected area and examined under a microscope. It's the most accurate way to diagnose SCCA [6].
• Anoscopy: An anoscopy is an examination that uses a special scope to look inside the anus and rectum for growths or other signs of cancer [8].
• Imaging Studies: Imaging studies such as CT scans, MRI, and PET scans can help determine if the cancer has spread to other parts of the body [3].

Staging Procedures

After a diagnosis is made, staging procedures are used to determine the extent of cancer in the body. Staging procedures for anal SCCA include:

• Nodal Stage (pN): The nodal stage is determined by examining lymph nodes for cancer cells. A nodal stage of 0 or 1 indicates no cancer cells are seen in any of the lymph nodes examined [10].

These diagnostic tests and staging procedures help healthcare professionals determine the best course of treatment for anal SCCA.

References:

[1] - This test can help tell if the cancer has spread into the lymph nodes or to other parts of the body, such as the liver, lungs, or other organs. (Search result 1) [3] - Staging procedures for anal canal cancer can include anoscopy, biopsy, computed tomography, MRI, endoanal ultrasound imaging, and/or 18F-fluorodeoxyglucose positron emission tomography (PET) scans. (Search result 3) [6] - A biopsy is a procedure where a sample of tissue is taken from the affected area and examined under a microscope. It's the most accurate way to diagnose SCCA. (Search result 6) [8] - An anoscopy is an examination that uses a special scope to look inside the anus and rectum for growths or other signs of cancer. (Search result 8) [10] - Nodal stage 1 is divided into 1a, 1b, and 1c based on where the lymph nodes invaded by cancer cells are located in the body. (Search result 10)

Chemotherapy Options for Anal Squamous Cell Carcinoma

Anal squamous cell carcinoma (SCCA) can be treated with various chemotherapy regimens, depending on the stage and location of the cancer. Here are some common chemotherapy options:

• 5-fluorouracil (5-FU) and mitomycin: This is a commonly used combination for treating anal SCCA, especially in cases where the cancer has not spread to distant sites.
• 5-FU and cisplatin: This combination can be used as an alternative to 5-FU and mitomycin, particularly in patients who cannot tolerate mitomycin or have advanced disease.
• Docetaxel, cisplatin, and fluorouracil (DCF): This regimen is sometimes used for treating advanced anal SCCA.

Immune Checkpoint Inhibitors

Recent studies have explored the use of immune checkpoint inhibitors (ICIs) in treating anal SCCA. These medications work by boosting the body's immune response to cancer cells. Some examples include:

• Nivolumab: This ICI has been shown to be effective in treating advanced anal SCCA, particularly when used as a monotherapy.
• Pembrolizumab: Another ICI that may be considered for treating anal SCCA, especially in cases where the cancer has not responded to other treatments.

Off-Label Chemotherapies

While there is no FDA-approved chemotherapy specifically designed for treating anal SCCA, off-label chemotherapies such as paclitaxel plus carboplatin or cisplatin/fluorouracil may be used in certain cases.

It's essential to note that the choice of chemotherapy regimen will depend on various factors, including the stage and location of the cancer, overall health, and medical history. A healthcare professional can provide personalized guidance on the most suitable treatment options.

References:

• [4] European Medicines Agency and Food and Drug Administration approved a vaccine for primary prevention from HPV-correlated ...
• [14] Chemotherapy drugs used to treat anal cancer.
• [9] The combination of 5-FU and cisplatin can also be used, especially in people who can't get mitomycin or for advanced anal cancer.
• [15] The more common squamous cell carcinoma of the anal canal as well as large perianal tumors invading the sphincter or rectum are treated with combined-modality external radiation with simultaneous chemotherapy (5-fluorouracil or capecitabine plus mitomycin).

Differential Diagnoses for Anal Squamous Cell Carcinoma

Anal squamous cell carcinoma, a type of cancer that affects the anus, can be challenging to diagnose due to its similarity in symptoms with other conditions. The following are some differential diagnoses for anal squamous cell carcinoma:

• Thrombosed hemorrhoids: These are swollen and inflamed veins in the rectum or anus, which can cause similar symptoms to anal squamous cell carcinoma.
• Anal warts: Caused by human papillomavirus (HPV), these growths on the skin around the anus can be mistaken for cancerous lesions.
• Low rectal cancer: Cancer that affects the lower part of the rectum can have similar symptoms to anal squamous cell carcinoma, such as bleeding and pain during