Background

Intestinal polypoid adenomas are a type of benign tumor that can develop in the inner lining of the gastrointestinal tract, particularly in the colon and rectum. These adenomas are often considered precursors to colorectal cancer, as they can undergo a transformation into malignant tumors over time if left untreated.  

Adenomas are characterized by the abnormal growth of glandular cells in the mucous membrane lining of the intestines. The term “polypoid” refers to the growth pattern, where the adenoma appears as a polyp, a protruding mass from the mucosal surface. People with a family history of colorectal polyps or cancer have an elevated risk. 

Epidemiology

Intestinal polypoid adenomas are common in the general population, especially in older individuals. The prevalence tends to increase with age, and adenomas are more frequently detected in individuals over 50 years old. 

The incidence of intestinal polypoid adenomas is influenced by various factors, including age, genetics, and lifestyle. There may be variations in the prevalence and incidence based on demographic factors such as gender and race. Men tend to have a slightly higher incidence of colorectal adenomas compared to women. 

Anatomy

Pathophysiology

Etiology

Mutations in the adenomatous polyposis coli (APC) gene are commonly associated with the development of intestinal polypoid adenomas. The APC gene is a tumor suppressor gene that regulates cell growth and prevents the formation of tumors. Inactivation of APC is an early event in the adenoma-carcinoma sequence. 

Individuals with FAP inherit a mutated APC gene, leading to the development of numerous adenomas in the colon and rectum. Without intervention, individuals with FAP have a significantly increased risk of developing colorectal cancer. 

Additional genetic alterations, such as mutations in the KRAS and TP53 genes, often occur in the progression of adenomas to colorectal cancer. KRAS mutations contribute to uncontrolled cell growth, while TP53 mutations disrupt cell cycle regulation and promote genomic instability. 

Genetics

Prognostic Factors

Larger adenomas generally have a higher risk of containing advanced dysplasia or progressing to colorectal cancer. Adenomas are often classified based on size, with larger adenomas carrying a greater risk. 

The histological grade of dysplasia within an adenoma is a crucial prognostic factor. Adenomas with high-grade dysplasia have a greater potential for malignant transformation compared to those with low-grade dysplasia. 

Individuals with multiple adenomas, especially in the presence of familial adenomatous polyposis (FAP) or other hereditary conditions, may have an increased risk of colorectal cancer. Adenomas with a villous or tubulovillous architecture are associated with a higher risk of malignancy compared to adenomas with a tubular architecture. 

Sessile serrated adenomas (SSAs) are a subtype of colorectal adenomas associated with an increased risk of interval cancers. These adenomas have specific histological features and may contribute to a more aggressive clinical course. 

Clinical History

Age Group:  

The prevalence of intestinal polypoid adenomas tends to increase with age. Individuals in their 50s and older are more likely to develop these adenomas compared to younger age groups. 

Screening guidelines for colorectal cancer, including the detection and removal of adenomas during colonoscopy, often recommend starting regular screenings at age 50 for average-risk individuals.  

Physical Examination

• Abdominal Examination: Palpation of the abdomen may reveal tenderness, masses, or other abnormalities that could be associated with advanced adenomas or complications such as obstruction.  
• Anemia and Systemic Symptoms: In cases where adenomas cause bleeding, patients may present with signs of anemia, such as pallor and weakness. Systemic symptoms like unintended weight loss, fatigue, or changes in appetite may be associated with advanced adenomas or malignant transformation. 
• Occult Blood Testing: Occult blood testing may be performed during a routine physical examination, especially if a patient reports symptoms like rectal bleeding or if there are risk factors for colorectal cancer. Positive findings may prompt further investigation, such as a colonoscopy. 

Age group

Associated comorbidity

Individuals with chronic inflammatory conditions of the colon, such as ulcerative colitis or Crohn’s disease, have an increased risk of developing colorectal adenomas. Chronic inflammation is a known risk factor for the development of adenomas and may influence their growth. 

Individuals with hereditary conditions, such as familial adenomatous polyposis (FAP) or Lynch syndrome, are predisposed to the development of numerous adenomas in the colon. These conditions are associated with specific genetic mutations and carry an elevated risk of colorectal cancer. 

While not a comorbidity, age is an important factor. The risk of developing intestinal polypoid adenomas increases with age, and they are more commonly found in older individuals. 

Obesity has been linked to an increased risk of colorectal adenomas. A diet high in fat and low in fiber, often associated with obesity, may contribute to the development of adenomas. 

Associated activity

Acuity of presentation

Adenomas are frequently discovered incidentally during imaging studies or colonoscopies performed for unrelated reasons. This is particularly true for smaller adenomas that may not cause noticeable symptoms. 

Larger adenomas or those with a tendency to bleed can cause occult or visible blood in the stool. Rectal bleeding may be an indication of advanced adenomas, and it could be associated with symptoms like changes in stool or rectal bleeding. 

While uncommon, larger adenomas or those causing obstruction can lead to abdominal pain. This is more likely if the adenoma is in a way that obstructs the bowel. 

Differential Diagnoses

• Colorectal Adenocarcinoma: Colorectal cancer shares symptoms with intestinal polypoid adenomas, including rectal bleeding, changes in bowel habits, and abdominal pain. A colonoscopy is typically performed to distinguish between benign adenomas and malignant tumors. 
• Diverticulosis and Diverticulitis: Diverticulosis and diverticulitis can cause abdominal pain, changes in bowel habits, and rectal bleeding. Diverticula are pouch-like protrusions that can form in the colon, and inflammation of these pouches (diverticulitis) may mimic symptoms of adenomas. 
• Inflammatory Bowel Disease (IBD): Conditions such as ulcerative colitis and Crohn’s disease can cause inflammation of the colon, leading to symptoms like abdominal pain, diarrhea, rectal bleeding, and changes in bowel habits.  
• Anal Fissures: Anal fissures, small tears in the lining of the anus, can cause rectal bleeding and pain during bowel movements.  
• Ischemic Colitis: Ischemic colitis, caused by reduced blood flow to the colon, can result in abdominal pain, bloody stools, and changes in bowel habits.  

• Infectious Colitis: Colonic infections, whether bacterial, viral, or parasitic, can cause symptoms such as diarrhea, abdominal pain, and rectal bleeding. Infectious colitis is usually associated with a recent infection. 
• Irritable Bowel Syndrome (IBS): IBS is a functional gastrointestinal disorder characterized by symptoms like abdominal pain, bloating, and changes in bowel habits. 

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

• Colonoscopy and Polypectomy: Colonoscopy is the primary method for detecting and diagnosing intestinal polypoid adenomas. During a colonoscopy, adenomas can be visualized, and if identified, they can be removed through a procedure called polypectomy. 

Polypectomy involves using a wire loop or other tools to excise the adenoma from the colon lining. This is often done during the same colonoscopy procedure. 

• Endoscopic Mucosal Resection (EMR): In cases where adenomas are large or have specific characteristics, endoscopic mucosal resection may be performed. EMR involves removing larger portions of the mucosal layer containing the adenoma. 
• Surgery: Surgical intervention may be necessary in cases where adenomas are too large or complex for endoscopic removal.  

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

use-of-non-pharmacological-approach-for-intestinal-polypoid-adenomas

• Dietary Modifications: A diet high in fiber, particularly from fruits, vegetables, and whole grains, has been associated with a reduced risk of colorectal adenomas. Fiber promotes regular bowel movements and may help prevent the development of adenomas. 
• Regular Exercise: Engaging in regular physical activity is associated with a lower risk of colorectal adenomas. Exercise helps maintain a healthy weight and promotes overall well-being. 
• Weight Management: Obesity has been identified as a risk factor for colorectal adenomas. Maintaining a healthy weight through a balanced diet and regular exercise may reduce the risk. 
• Tobacco Cessation: Smoking is associated with an increased risk of colorectal adenomas. Quitting smoking can have various health benefits, including a lower risk of adenoma development. 

Role of NSAID’s

• Sulindac: It is a traditional NSAID that has been studied for its potential chemo preventive effects in individuals with FAP. 
• Celecoxib: Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor, which means it specifically targets the COX-2 enzyme involved in inflammation. 

COX-2 is overexpressed in colorectal adenomas and cancers, and inhibiting it is thought to have a potential chemo preventive effect. 

use-of-intervention-with-a-procedure-in-treating-intestinal-polypoid-adenomas

• Colonoscopy: Colonoscopy is a procedure that allows a healthcare provider to examine the entire colon using a flexible, lighted tube with a camera on the end (colonoscope).  
• Polypectomy: If adenomas are identified during a colonoscopy, they can be removed through a procedure called polypectomy. There are different methods of polypectomy, including: 
• Snare Polypectomy: A wire loop is passed through the colonoscope to surround the adenoma, and then it is cut or cauterized to remove the tissue. 
• Endoscopic Mucosal Resection (EMR): For larger adenomas that cannot be completely removed with standard polypectomy, endoscopic mucosal resection (EMR) may be performed. This involves removing a larger portion of the mucosal layer containing the adenoma. 
• Endoscopic Submucosal Dissection (ESD): Endoscopic submucosal dissection is a more advanced technique that allows for the removal of larger lesions or those with challenging characteristics. 

use-of-phases-in-managing-treating-intestinal-polypoid-adenomas

• Diagnosis: The management process often begins with routine colorectal cancer screening for average-risk individuals, typically starting around the age of 50. If adenomas are suspected or identified during screening, a colonoscopy is performed for a more detailed examination. 
• Regular Follow-Up Colonoscopies: Surveillance colonoscopies play a crucial role in the long-term management of intestinal polypoid adenomas. These follow-up procedures aim to monitor for the recurrence of adenomas or the development of new lesions. 

• Diet and Exercise: Lifestyle modifications, including a healthy diet rich in fibre, regular exercise, and weight management, may contribute to a lower risk of adenoma recurrence. 
• Tobacco and Alcohol Cessation: Quitting smoking and moderating alcohol consumption can also be beneficial in reducing the risk of adenoma development. 

Medication

Future Trends

Media Gallary

References

Adenomatous Polyp in Colon: Meaning and Cancer Risk (verywellhealth) 

Adenomatous Polyps of the Colon | NEJM