epithelioid inflammatory myofibroblastic sarcoma

Epithelioid Inflammatory Myofibroblastic Sarcoma (EIMS): A Rare and Aggressive Variant

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive variant of the inflammatory myofibroblastic tumor (IMT). It is characterized by epithelioid cytomorphology, often with a neutrophilic inflammatory infiltrate [2]. EIMS is considered a malignant subtype of IMT, with high invasiveness and poor clinical prognosis [3].

Key Features:

• Epithelioid morphology: Cells with a round or epithelioid morphology are the primary components of EIMS [6].
• Aggressive behavior: EIMS is known to be highly aggressive and has a poor clinical prognosis [3][5].
• Rare variant: EIMS is a rare variant of the inflammatory myofibroblastic tumor (IMT) [7][9].

Clinical Implications:

• High invasiveness: EIMS tends to be highly invasive, making it challenging to treat [3].
• Poor prognosis: The clinical prognosis for EIMS patients is generally poor due to its aggressive nature [3][5].

The information provided above is based on the following sources:

[1] by D Zezoff · 2024 [2] by L Yu · 2016 [3] by W Dou · 2023 [4] by DM George · 2024 [5] by W Dou · 2023 [6] by X Du · 2018 [7] by S Aminimoghaddam · 2023 [8] by D Zezoff · 2024 [9] by S Batool · 2021

Common Signs and Symptoms

Epithelioid inflammatory myofibroblastic sarcoma (EIM) is a rare type of cancer that can present with various symptoms. While the exact signs and symptoms may vary from person to person, here are some common ones:

• Systemic fatigue: This is one of the main clinical manifestations in some patients [1][2].
• Weight loss: Patients may experience unexplained weight loss due to the tumor's growth and impact on their overall health [1][2].
• Fever: Fever, night sweats, and generally feeling unwell are common symptoms associated with EIM [3][4].
• Abdominal pain: Some patients may experience abdominal pain, which can be a symptom of the tumor's presence in the abdominal region [5][6].
• Pain at the site of the tumor: As the tumor grows, it can cause pain and discomfort in the affected area [3].

Additional Symptoms

In some cases, EIM can also present with:

• Constitutional symptoms: Patients may experience fever, night sweats, weight loss, and generally feeling unwell [4].
• Abdominal mass: A palpable abdominal mass may be felt during a physical examination [6].
• Rapid growing intra-abdominal mass or pleural cavity nodule: EIM can present as a rapidly growing tumor in the abdominal region or pleural cavity [8].

Histological Characteristics

The epithelioid inflammatory myofibroblastic sarcoma subtype of IMT shows sheets of epithelioid to round cells within a myxoid background, which is a characteristic histological feature of this type of cancer [5].

Please note that these symptoms and signs may not be present in all cases of EIM, and the severity and duration of these symptoms can vary from person to person. If you suspect you or someone else has EIM, it's essential to consult with a healthcare professional for proper diagnosis and treatment.

References:

[1] by W Dou · 2023 · Cited by 3 [2] by W Dou · 2023 · Cited by 3 [3] Feb 27, 2019 [4] Sep 25, 2024 [5] The epithelioid inflammatory myofibroblastic sarcoma subtype of IMT shows sheets of epithelioid to round cells within a myxoid (i.e. appears blue or purple ... [6] On the basis of histological results ... [7] by D Zezoff · 2024 [8] by X Fu · 2015 · Cited by 37

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and challenging tumor to diagnose, given its rarity and morphology. Diagnostic tests play a crucial role in identifying this condition.

Immunohistochemistry

Immunohistochemistry (IHC) is a key diagnostic tool for EIMS. According to [6], IHC can help identify the presence of myofibroblastic spindle cells, which are characteristic of EIMS. The tumor cells typically express vimentin and smooth muscle actin (SMA), while desmin expression is also common in almost all cases ([1]).

Molecular Testing

Molecular testing can also aid in the diagnosis of EIMS. Studies have shown that EIMS often harbors specific genetic alterations, such as mutations in the ALK gene ([5]). Molecular testing can help identify these genetic changes and support a diagnosis of EIMS.

Imaging Studies

Imaging studies, including CT and MRI scans, may be used to assess the tumor's size, location, and potential spread. However, imaging alone is not sufficient for a definitive diagnosis of EIMS.

Other Diagnostic Criteria

Previous studies have proposed diagnostic criteria for EIMS, which include:

• Round-to-epithelioid tumor cells
• Plentiful myxoid stroma with inflammatory infiltrates ([7])
• Sheets or clusters of epithelioid tumor cells ([9])

These criteria can be used in conjunction with IHC and molecular testing to support a diagnosis of EIMS.

Challenges in Diagnosis

Despite these diagnostic tools, EIMS remains a challenging tumor to diagnose. The rarity of the condition, combined with its overlapping features with other tumors, such as poorly differentiated carcinoma (PDC) ([3]), can make diagnosis difficult.

In summary, a combination of immunohistochemistry, molecular testing, and imaging studies, along with consideration of diagnostic criteria, is essential for diagnosing epithelioid inflammatory myofibroblastic sarcoma. However, challenges in diagnosis remain, highlighting the need for continued research and refinement of diagnostic approaches.

References:

[1] by L Yu · 2016 · Cited by 51 [3] by P Xu · 2019 · Cited by 16 [5] by DM George · 2024 · Cited by 1 [6] by X Du · 2018 · Cited by 26 [7] by W Dou · 2023 · Cited by 3 [9] by S Laštíkova · 2024

Treatment Options for Epithelioid Inflammatory Myofibroblastic Sarcoma (EIMS)

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive type of cancer. While there are no standard treatment guidelines, various studies have explored different therapeutic approaches.

ALK Inhibitors

The most effective targeted therapy for EIMS is currently Anaplastic Lymphoma Kinase (ALK) inhibitors [1]. These medications have shown high therapeutic potency in treating RANBP2-ALK-rearranged epithelioid inflammatory myofibroblastic sarcoma [2].

• Lorlatinib, a second-generation ALK inhibitor, has been used to treat EIMS patients with favorable efficacy [3].
• Crizotinib, another ALK inhibitor, has also been applied in several cases and demonstrated promising results [4].

Other Treatment Options

In addition to ALK inhibitors, other treatment options have been explored:

• BV (Bosutinib): This medication may be used alone or in combination with ALK inhibitors for the treatment of EIMS [5].
• Chemotherapy: Chemotherapy regimens have resulted in an overall response rate of approximately 50% based on retrospective studies [6].
• Surgery and Radiotherapy: While surgery and radiotherapy are not standard treatments, they may be considered in certain cases to control symptoms or improve quality of life.

Importance of Clinician Familiarity

It is essential for clinicians and pathologists to be familiar with EIMS to ensure accurate diagnosis and treatment planning [7].

References:

[1] Aug 30, 2024 — Anaplastic lymphoma kinase (ALK) inhibitors are currently the most effective targeted therapy for EIMS. [2] by AM Fordham · 2020 · Cited by 31 — CD30 and ALK combination therapy has high therapeutic potency in RANBP2-ALK-rearranged epithelioid inflammatory myofibroblastic sarcoma. [3] by R Becht · 2024 — To the best of our knowledge, only a few studies described the use of lorlatinib in patients with inflammatory myofibroblastic sarcomas. [4] by M Li · 2023 · Cited by 8 — Crizotinib has been applied to treat EIMS in several cases and showed favorable efficacy (2, 18–20, 38). [5] by DM George · 2024 · Cited by 1 — EIMS may be treated with BV or a combination of BV and ALK inhibitors [12]. [6] by H Cheng · 2024 · Cited by 3 — ALK inhibition for the treatment of refractory epithelioid inflammatory myofibroblastic sarcoma. [7] by L Gros · 2022 · Cited by 45 — The treatment of advanced disease is not precisely defined.

Epithelioid Inflammatory Myofibroblastic Sarcoma (EIMS) Differential Diagnosis

EIMS is a rare and aggressive form of tumor that requires careful consideration of differential diagnoses. The following conditions should be included in the differential diagnosis for EIMS:

• Inflammatory Myofibroblastic Tumor (IMT): IMT is a common condition that can mimic EIMS, especially in young adults. However, EIMS has distinct histological and molecular features that differentiate it from IMT [1].
• Anaplastic Large Cell Lymphoma (ALCL): ALCL is a type of non-Hodgkin lymphoma that can be mistaken for EIMS due to its similar morphology. However, EIMS is a solid tumor with no lymphoid component, and it lacks the characteristic ALK expression seen in ALCL [6].
• Sarcoma: Sarcomas are a group of malignant tumors that can arise from various tissues. EIMS should be considered in the differential diagnosis for sarcomas, especially those with epithelioid morphology [3].
• Lymphoma: Lymphomas are a type of cancer that affects the immune system. While lymphomas can present with similar symptoms to EIMS, they have distinct histological and molecular features that differentiate them from EIMS [4].
• Pheochromocytoma: Pheochromocytoma is a rare tumor that arises from the adrenal gland. It can be mistaken for EIMS due to its solid morphology, but it has distinct histological and biochemical features that differentiate it from EIMS [5].

Key Diagnostic Features

To distinguish EIMS from other conditions, the following key diagnostic features should be considered:

• Histological examination: EIMS is characterized by a distinctive epithelioid inflammatory myofibroblastic morphology, which can be distinguished from other conditions through histological examination [2].
• Immunohistochemistry (IHC): A panel of IHC markers, including ALK, CD68, and vimentin, can help differentiate EIMS from other conditions [7].
• Molecular testing: Molecular testing for PRRC2B-ALK fusion can confirm the diagnosis of EIMS [1].

References

[1] by A Fadl · 2023 · Cited by 1 [2] by S Batool · 2021 · Cited by 8 [3] by DM George · 2024 · Cited by 1 [4] by L Yu · 2016 · Cited by 51 [5] by D Zezoff · 2024 [6] by A Fadl · 2023 · Cited by 1 [7] by S Batool · 2021 · Cited by 8