What are the other Names for this Condition? (Also known as/Synonyms)

• Colonic Inflammatory Myofibroblastic Tumor
• IMT of Large Bowel
• Inflammatory Myofibroblastic Tumor of Large Intestine

What is Inflammatory Myofibroblastic Tumor of Colon? (Definition/Background Information)

• Inflammatory Myofibroblastic Tumor of Colon is a very rare, mostly benign tumor of the colon (large intestine). They can grow to large sizes and generally occur in younger populations
• Inflammatory myofibroblastic tumor (IMT) is generally considered as a benign tumor with aggressive behavior (low-grade tumor), which can occur anywhere in the body
• The cause of Colonic Inflammatory Myofibroblastic Tumor is generally unknown, though it may be associated with genetic mutations. There are generally no well-established risk factors for this tumor type
• The signs and symptoms are generally non-specific, but may include abdominal pain, nausea, and bleeding from the rectum. Complications, such as tumor recurrence on partial removal, is known to occur
• The mainstay of treatment is a surgical excision that can be curative. The prognosis of Inflammatory Myofibroblastic Tumor of Colon is generally good on tumor removal, but some tumors are known to recur and/or even metastasize (rare cases)

Who gets Inflammatory Myofibroblastic Tumor of Colon? (Age and Sex Distribution)

• Inflammatory Myofibroblastic Tumor of Colon is typically seen in young adults and children, including in newborns and infants
• Very few cases of IMT of Colon have been recorded in the medical literature
• Both males and females are affected and no gender preference is seen
• All races and ethnic groups are at risk for the condition

Note: Most inflammatory myofibroblastic tumors are found in the lung, which is the most common site of the tumor. In such cases, these tumors are frequently diagnosed in middle-aged adults. However, in contrast, the average age of presentation for extrapulmonary IMT (IMT outside the lung) is around 10 years.

What are the Risk Factors for Inflammatory Myofibroblastic Tumor of Colon? (Predisposing Factors)

• Presently, the specific risk factors for Colonic Inflammatory Myofibroblastic Tumor are unknown or unidentified
• However, some studies indicate that history of abdominal surgery may be a risk factor

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Inflammatory Myofibroblastic Tumor of Colon? (Etiology)

The cause of development of Inflammatory Myofibroblastic Tumor of Colon is generally unknown.

• Some research scientists believe that the cause of the condition is mostly due to genetic mutations, which results in tumor formation. In over 40% of the tumors, ALK gene mutation has been observed
• Some believe that the inflammatory myofibroblastic tumor is the result of an inflammatory reactive process (such as due to a surgery) and not a true tumor
• It is also believed by some researchers that the tumor may arise due to viral infections caused by human herpes virus 8 (HHV8) or Epstein-Barr virus (EBV)

What are the Sign and Symptoms of Inflammatory Myofibroblastic Tumor of Colon?

The signs and symptoms depend on the size of the tumor. Specific signs and symptoms of Inflammatory Myofibroblastic Tumor of Colon are generally not observed. The presentations are based upon the site of tumor in the large intestine and may include:

• Small tumors usually do not cause any symptoms. But, occasionally they may become painful, if they compress surrounding structure
• Pain within the abdominal region; chest pain
• Nausea
• Diarrhea or constipation
• Anemia; increased platelet count
• Bleeding from the rectum (following bowel movement)
• Fever and weight loss in some cases
• Loss of appetite
• Enlarged lymph nodes may be observed in some cases
• Intestinal obstruction due to large tumor sizes
• Large size tumors are known to ulcerate

The tumor is solid and well-defined and commonly found at the right side of the colon. It ranges in size from 3-12 cm. The tumor is also seen in the peritoneal folds (mesentery and omentum, which are the fats connected to the small intestine). Some tumors are known to occur in the rectum.

How is Inflammatory Myofibroblastic Tumor of Colon Diagnosed?

A diagnosis of Inflammatory Myofibroblastic Tumor of Colon may be undertaken using the following tests and exams:

• Complete evaluation of family (medical) history, along with a thorough physical examination
• Stool sample analysis
• Screening colonoscopy: IMTs of Colon may be diagnosed during colonoscopies. A colonoscopy is a test that allows the physician to look at the inner lining of the colon and rectum. A typical colonoscopy involves using a thin, flexible tube (called a colonoscope), with an attached video camera, to view the colon and rectum
• Lower gastrointestinal series, which are a combination of analysis methods, combining X-rays and barium to visualize the intestinal region
• Tissue biopsy of the tumor:
  • A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
  • Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
  • Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

Note: Inflammatory Myofibroblastic Tumors are very rare. Due to this, it typically causes diagnostic challenges to the pathologist while trying to establish an accurate diagnosis.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Inflammatory Myofibroblastic Tumor of Colon?

Some potential complications of Inflammatory Myofibroblastic Tumor of Colon include:

• They can mimic colon cancer and cause considerable emotional stress in the affected individual
• Intussusception: When one part of the intestine pushes itself into another part of the intestine, causing obstruction of the bowel
• Recurrence of the tumor after treatment, especially due to partial removal of IMT

IMTs are considered to be low-grade tumors and in a majority of individuals, they do not show any malignancy (95% or more cases). However, in about 5% of the individuals, the tumor can undergo a malignant transformation (called Malignant Inflammatory Myofibroblastic Tumor). In such cases, metastasis has been observed that may even result in fatal outcomes.

How is Inflammatory Myofibroblastic Tumor of Colon Treated?

Inflammatory Myofibroblastic Tumor of Colon may be treated through the following measures:

• Surgical removal of the entire tumor is the preferred method of treatment
• In young children, if the tumors cannot be surgically removed, then corticosteroid administration is found to be beneficial
• Orally administered NSAIDs may be effective as anti-inflammatory medication, along with other treatment tools
• Chemotherapy may help, if the condition recurs, if there is a local invasion, or a distant metastasis is noted (in very rare cases). However, chemotherapy is mostly administered following surgery
• Occasionally, some tumors are known to disappear over time, without any treatment

Observation and periodic checkups to monitor the condition is recommended following treatment.

How can Inflammatory Myofibroblastic Tumor of Colon be Prevented?

Presently, there are no specific methods or guidelines to prevent Inflammatory Myofibroblastic Tumor of Large Intestine.

What is the Prognosis of Inflammatory Myofibroblastic Tumor of Colon? (Outcomes/Resolutions)

• An early diagnosis and prompt treatment of Inflammatory Myofibroblastic Tumor of Colon generally yields better outcomes than a late diagnosis and delayed treatment
• The prognosis on timely surgical removal of the tumor is generally good. Some tumors are known to spontaneously regress and disappear
• On a complete excision and removal, Colonic IMT is generally not known to recur. Some tumors are known to recur and/or even metastasize (occasionally)

Additional and Relevant Useful Information for Inflammatory Myofibroblastic Tumor of Colon:

The following article link will help you understand other cancers and benign tumors:

http://www.dovemed.com/diseases-conditions/cancer/