Summary about Disease
Inflammatory pseudotumor (IPT), also known as inflammatory myofibroblastic tumor (IMT), is a rare lesion characterized by a mass-like collection of inflammatory cells and spindle cells (myofibroblasts). It can occur in virtually any organ of the body, but is most commonly found in the lungs, orbit, and retroperitoneum. It is considered a benign or low-grade neoplasm, but can sometimes exhibit aggressive behavior or recur after treatment. While the exact nature of IPT remains unclear, it is thought to be a reactive process to injury or infection in some cases, while others might represent true neoplastic lesions.
Symptoms
Symptoms vary widely depending on the location and size of the inflammatory pseudotumor. Common symptoms include:
Lungs: Cough, shortness of breath, chest pain, wheezing, hemoptysis (coughing up blood)
Orbit (Eye): Proptosis (bulging of the eye), diplopia (double vision), vision loss, pain, swelling around the eye
Retroperitoneum (Abdomen): Abdominal pain, palpable mass, bowel obstruction, urinary problems
Other Sites: Symptoms may be related to compression or obstruction of adjacent structures. General symptoms like fever, weight loss, and fatigue may occur but are less common.
Causes
The exact cause of inflammatory pseudotumor is unknown. Several factors are believed to contribute to its development:
Infection: Some cases have been linked to bacterial or viral infections, such as E. coli, *Klebsiella*, *Actinomyces*, and Epstein-Barr virus (EBV).
Trauma: Prior trauma or surgery may play a role in some cases.
Immune Dysregulation: An abnormal immune response might contribute to the inflammatory process.
Genetic Factors: Rearrangements in the ALK gene have been identified in a subset of IPT cases, suggesting a possible neoplastic component. However, most cases do not have a clear genetic cause.
Medicine Used
Treatment approaches vary depending on the location, size, and symptoms of the inflammatory pseudotumor. Commonly used medicines include:
Corticosteroids: Prednisone or other corticosteroids are often the first-line treatment to reduce inflammation.
Nonsteroidal Anti-inflammatory Drugs (NSAIDs): Can provide some symptom relief in some cases.
Immunosuppressants: Medications like methotrexate, azathioprine, or cyclosporine may be used if corticosteroids are ineffective or to reduce steroid dependence.
ALK Inhibitors: For IPTs with ALK gene rearrangements, ALK inhibitors like crizotinib, ceritinib, or alectinib may be used.
Chemotherapy: May be considered in aggressive or refractory cases.
Antibiotics or Antivirals: If an infection is suspected, appropriate antimicrobial therapy may be used.
Is Communicable
Inflammatory pseudotumor is not communicable. It is not an infectious disease and cannot be spread from person to person.
Precautions
There are no specific precautions to prevent inflammatory pseudotumor, as the exact causes are not fully understood. Maintaining a healthy lifestyle, addressing underlying infections promptly, and avoiding unnecessary trauma may be beneficial but are not proven to prevent IPT.
How long does an outbreak last?
The duration of an inflammatory pseudotumor is highly variable. Some lesions may resolve spontaneously or with treatment over weeks or months. Others may persist for years or even recur after treatment. The duration depends on factors such as the location, size, aggressiveness, and response to therapy.
How is it diagnosed?
Diagnosis of inflammatory pseudotumor typically involves a combination of:
Imaging Studies: X-rays, CT scans, MRI scans, and PET scans can help visualize the lesion and assess its size, location, and involvement of surrounding structures.
Biopsy: A tissue sample is obtained through needle biopsy or surgical excision and examined under a microscope to confirm the diagnosis and rule out other conditions.
Immunohistochemistry: Special stains are used on the biopsy sample to identify specific markers that can help distinguish IPT from other tumors and to assess for ALK gene rearrangements.
Clinical Evaluation: A thorough medical history and physical examination are important to assess symptoms and identify potential risk factors.
Timeline of Symptoms
The timeline of symptoms can vary greatly depending on the location and growth rate of the IPT.
Gradual Onset: Many IPTs present with a gradual onset of symptoms over weeks or months.
Insidious Development: Some IPTs may be asymptomatic initially and are discovered incidentally during imaging for other reasons.
Rapid Progression: In rare cases, IPTs can grow rapidly and cause more severe symptoms within a short period.
Fluctuating Symptoms: Some patients may experience periods of symptom improvement followed by exacerbations.
Important Considerations
Differential Diagnosis: Inflammatory pseudotumor can mimic other benign and malignant conditions, so it's important to consider other possibilities during diagnosis.
Multidisciplinary Approach: Management of IPT often requires a team of specialists, including surgeons, oncologists, radiologists, and pathologists.
Long-Term Follow-up: Patients with IPT require long-term follow-up to monitor for recurrence or disease progression.
Clinical Trials: Participation in clinical trials may be an option for patients with aggressive or refractory IPT.
Psychological Support: Dealing with a rare and potentially chronic condition can be emotionally challenging, and psychological support may be helpful.