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

• Gastric Inflammatory Pseudotumor
• Inflammatory Fibrosarcoma of Stomach
• Plasma Cell Granuloma of Stomach

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

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

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

• Inflammatory Myofibroblastic Tumor of Stomach is typically seen in young adults and children, including in newborns and infants
• Both males and females are affected and no gender preference is noted
• 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 Stomach? (Predisposing Factors)

• Presently, the specific risk factors for Inflammatory Myofibroblastic Tumor of Stomach are unknown or unidentified

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s 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 Stomach? (Etiology)

The cause of development of Inflammatory Myofibroblastic Tumor of Stomach 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
• The ALK gene may exhibit fusion with any of the following genes - ATIC, CLTC, RANBP2, TPM3 or TPM4 genes
• Some believe that the inflammatory myofibroblastic tumor is the result of an inflammatory reactive process and that it is 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 Stomach?

The signs and symptoms depend on the size of the tumor. Specific signs and symptoms of Inflammatory Myofibroblastic Tumor of Stomach are generally not observed, especially when the tumors are small. In some cases, large tumors may present the following symptoms:

• Feeling of abdominal discomfort; abdominal cramps or abdominal pain
• Mild abdominal tenderness
• Irregular bowel movement
• Malabsorption
• Fever, weakness, and night sweats may be present
• Diarrhea, mostly in children
• The tumors are typically solitary; however, in some cases, more than one tumor may be seen
• Some tumors are seen outside of the GI tract
• The tumor size ranges from 1-2 cm to over 10 cm
• Small tumors may occasionally become painful, if they compress surrounding structures

How is Inflammatory Myofibroblastic Tumor of Stomach Diagnosed?

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

• Complete physical exam with evaluation of medical history
• Ultrasound scan of the stomach/abdomen: It is a non-invasive procedure that uses high frequency sound waves to produce real-time images
• Abdominal CT scan: It is a noninvasive procedure that provides more details of soft tissues, blood vessels, and internal organs
• Stool sample analysis
• Upper GI endoscopy: An endoscopic procedure is performed using an instrument called an endoscope, which consists of a thin tube and a camera. Using this technique, the radiologist can have a thorough examination of the insides of the gastrointestinal tract
• Chromoendoscopy can help detect small-sized tumors; small tumors can also be detected using narrow band imaging technique
• Endoscopic ultrasonography: During this procedure, fine needle aspiration biopsy (FNAB) can be performed on the affected area. This is good technique for tumor detection including tumor invasion parameters, and whether nearby lymph nodes are affected
• Vascular angiographic studies of the tumor
• Exploratory laparoscopy (diagnostic laparoscopy) may be required, if gastrointestinal symptoms are present. In this procedure, the abdomen is examined using a minimally-invasive technique, and a tissue biopsy and tissue for culture obtained
• Whole body PET scans to determine how far the cancer has spread to other organ systems, in case of malignancy
• Tissue biopsy of the tumor:
  • A tissue biopsy of the nodule 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
• Some tumors are mistaken for gastrointestinal stromal tumors (GISTs)
• It is reported to be difficult to differentiate between a benign tumor and a malignant tumor

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 Stomach?

Some potential complications of Inflammatory Myofibroblastic Tumor of Stomach include:

• They can mimic stomach cancer and cause considerable emotional stress in the affected individual
• Large tumors may considerably obstruct the gastric passage
• Recurrence of the tumor after treatment, especially due to partial removal of IMT
• Damage to the muscles, vital nerves, and blood vessels, during surgery
• Post-surgical infection at the wound site is a potential complication

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 Stomach Treated?

Inflammatory Myofibroblastic Tumor of Stomach 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
• Chemotherapy may help, if the condition recurs , if there is a local invasion, or a distant metastasis is noted (in very rare cases)
• Radiation therapy and chemotherapy (used following a surgery) are not found to be very useful treatment tools
• 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 Stomach be Prevented?

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

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

• An early diagnosis and prompt treatment of Inflammatory Myofibroblastic Tumor of Stomach generally yields better outcomes than a late diagnosis and delayed treatment
• The prognosis on timely surgical removal of the tumor is generally good. On a complete excision and removal, IMT of Stomach is generally not known to recur
• However, some tumors are known to recur on an incomplete removal, or can even metastasize (occasionally)

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

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

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