colorectal adenoma

A colorectal adenoma, also known as a colon adenoma, is a type of polyp that forms on the inner lining of the colon or rectum. It is a benign glandular tumor that can be considered a precursor lesion to colorectal cancer [1][2].

Characteristics:

• A colorectal adenoma is made up of gland-like tissue and varies in size and shape [14].
• There are different types of colorectal adenomas, based on how they look under a microscope, such as tubular adenomas [11].
• They often manifest as polyps and can be found during colonoscopies done to screen for colorectal cancer [5].

Definition:

• A colorectal adenoma is an epithelial tumor composed of abnormal glands of the large bowel [2].
• It is a type of neoplasm that is sometimes referred to as conventional adenoma to distinguish it from serrated lesions [11].

Microscopic Description:

• Tubular adenomas have conserved crypt architecture with variable elongation of the crypts and an increased number of glands [11].
• The microscopic description of colorectal adenomas can help determine their degree of severity and potential for malignancy [3].

In summary, a colorectal adenoma is a type of polyp that forms on the inner lining of the colon or rectum, made up of gland-like tissue, and has different characteristics based on its microscopic appearance.

Colorectal Adenoma Signs and Symptoms

Colorectal adenomas, also known as colon polyps, are small clumps of cells that form on the intestinal lining. While they are usually benign (non-cancerous), it's essential to be aware of their symptoms to ensure early detection and treatment.

Common Symptoms:

• Bleeding: One of the most common signs of colorectal adenoma is bleeding, which can manifest as blood in your stool or rectal bleeding. This can be a sign of colon polyps or other conditions.
• Abdominal Pain: A large colon polyp can block part of your bowel, leading to crampy abdominal pain.
• Dark or Bloody Stools: If you have bleeding polyps, you might notice dark red or bright red blood when you wipe yourself after a bowel movement.
• Anemia: In some cases, colorectal adenomas can cause anemia due to chronic bleeding.
• Changes in Bowel Habits: You may experience constipation or diarrhea that lasts more than a week.

Other Possible Symptoms:

• Mucus or Blood in Stool: A small amount of slime (mucus) or blood in your poo can be another sign of bowel polyps.
• Bleeding from the Rectum: Bleeding from the rectum is also a possible symptom of colorectal adenoma.

Important Note:

While these symptoms are common, it's essential to remember that many people with colorectal adenomas do not experience any symptoms at all. Regular screening and colonoscopies can help detect polyps before they become cancerous.

References:

• [1] Symptoms of colon adenoma · Anemia · Abdominal pain · Dark or bloody stools · Bleeding from your rectum · Constipation or diarrhea that lasts more than a week.
• [2] What are the symptoms of colon polyps? · Signs of colorectal bleeding. If you have bleeding polyps, you might notice blood in your poop or when you wipe.
• [3] Tubular adenomas rarely have symptoms. When they do, the most frequent symptom is finding painless bright red or dark red blood when you wipe yourself after ...
• [4] Symptoms of bowel polyps · a small amount of slime (mucus) or blood in your poo · bleeding from your bottom · a change in your normal bowel habits, such as ...

Colorectal adenomas are benign tumors in the colon or rectum that can potentially develop into colorectal cancer over time. Diagnostic tests for colorectal adenomas aim to detect and confirm

Treatment Options for Colorectal Adenomas

Colorectal adenomas are benign tumors that can develop into colorectal cancer if left untreated. The primary treatment for colorectal adenomas is surgical removal, but in some cases, drug treatment may be considered to prevent the growth of new polyps or reduce the risk of cancer.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Research has shown that NSAIDs, particularly aspirin, can reduce the risk of colorectal cancer and adenomas [7][8]. A study published in 2003 found that daily soluble aspirin was associated with a reduction in the risk for recurrent adenomas found at colonoscopy [8].

Targeted Drugs

Targeted drugs, such as erlotinib (Tarceva) and sulindac (Aflodac), have been studied for their potential to treat colorectal cancer. A combination treatment of erlotinib and sulindac decreased the number of adenomas in people with familial adenomatous polyposis (FAP) [5].

Other Treatment Options

High-dose celecoxib was also effective in patients with FAP, decreasing colorectal polyp burden by 31% after 6 months [4]. Additionally, nonsteroidal anti-inflammatory drugs (NSAIDs) may reduce the development of sporadic colorectal adenomas and cancer [6].

Adjuvant Treatment

Chemotherapy may be used as adjuvant treatment to prevent the recurrence of colorectal cancer. Adjuvant or neoadjuvant chemo is often given for a total of 3 to 6 months, depending on the drugs used [3].

References:

[4] BW Katona · 2020 · Cited by 174 [5] Mar 14, 2018 [6] by TK Asano · 2004 · Cited by 131 [7] by JA Baron · 2003 · Cited by 1848 [8] by R Benamouzig · 2003 · Cited by 501

The differential diagnosis of colorectal adenoma involves identifying other conditions that may present similarly to an adenoma in the colon or rectum. According to various medical sources [1, 5, 7], some of these differential diagnoses include:

• Invasive adenocarcinoma: This is a type of cancer that can arise from an adenoma and is considered a serious condition.
• Arteriovenous malformation (AVM): AVMs are abnormal connections between arteries and veins, which can be found in the colon or rectum.
• Carcinoid/neuroendocrine tumors: These are rare types of tumors that can occur in the gastrointestinal tract, including the colon or rectum.
• Recurrent malignancy: This refers to a recurrence of cancer in the same area as the original adenoma.

Additionally, other benign polyps may also be found in the large intestine, such as inflammatory fibroid polyps [3]. It's worth noting that while these conditions can present similarly to an adenoma, they often have distinct characteristics and require different diagnostic approaches.

In terms of diagnostic tools, endocytoscopy has been shown to be effective in determining the differential diagnosis of colorectal low-grade adenomas [6, 8].

References:

[1] Mar 9, 2020 — The differential diagnosis of colonic polyps varies, depending on the age of the patient and the presenting symptoms. [3] ... differential diagnosis includes recurrent malignancy. A range of other benign polyps may also be found in the large intestine e.g. inflammatory fibroid ... [5] by M Taherian · 2023 · Cited by 14 — Although a tumor of a benign nature, these adenomas are usually considered precancerous and can transform into malignant structures, in contrast to hyperplastic ... [6] by T Kudo · 2020 · Cited by 17 — Endocytoscopy is an effective modality in determining the differential diagnosis of colorectal low-grade adenoma. [7] by T Kudo · 2020 · Cited by 17 — Conclusions: Endocytoscopy is an effective modality in determining the differential diagnosis of colorectal low- grade adenoma.