Epithelioid inflammatory myofibroblastic sarcoma with VCL-ALK fusion of central nervous system: case report and brief review of the literature

Epithelioid Inflammatory Myofibroblastic Sarcoma: Case Series With a First Report of CLTC::ALK Fusion in an Aggressive Disease

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and clinically aggressive variant of inflammatory myofibroblastic tumor (IMT). It typically presents in children and young adults, often affecting the abdominal cavity. It is characterized by the presence of plump, polyhedral, and epithelioid cells, and a distinctive nuclear or perinuclear ALK staining on immunohistochemistry. Various ALK fusion partners have been identified in EIMS, including RANBP2, RRBP1, EML4, and VCL. In this report, we present four cases of EIMS involving the abdominal cavity, including the first case with a CLTC::ALK fusion, which has previously been associated only with nonaggressive IMT.

Rare giant epithelioid inflammatory myofibroblastic sarcoma of the abdominal cavity in a child: a case report and review of the literature

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a distinct subtype of inflammatory myofibroblastoma tumor (IMT) that is recognized as a rare malignant tumor characterized by anaplastic lymphoma kinase (ALK) positivity, significant aggressiveness, treatment challenges, and a poor prognosis. We report on the case of an 8-year-old boy presenting with abdominal pain and vomiting. Computed tomography (CT) of the abdomen revealed a large tumor, and the pathology results following a biopsy confirmed the diagnosis of EIMS. The patient underwent radical tumor resection, and genetic testing identified the presence of the RANBP2-ALK fusion. To our knowledge, this represents the largest pediatric case of abdominal EIMS documented in the literature. Currently, there is no standard therapy for EIMS; however, existing studies advocate for the use of ALK tyrosine kinase inhibitors (TKIs) in its treatment. This case was reported to be in remission following treatment with crizotinib, thereby contributing to the understanding of the specific pathology of EIMS and facilitating accurate diagnosis and targeted therapy.

Epithelioid inflammatory myofibroblastic sarcoma with exceptionally long response to lorlatinib-a case report

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive subtype of inflammatory myofibroblastic tumor. The disease is associated with rearrangements of the anaplastic lymphoma kinase (ALK). In this paper, we present the clinicopathological features and treatment of a female patient diagnosed with EIMS. In 2019, an 18-year-old female patient was admitted to the hospital with abdominal pain. Radiological examinations confirmed a large pelvic mass which was subsequently resected. After re-evaluation of the initial histologic diagnosis, the final diagnosis of EIMS was established. Consequently, due to the lack of response to chemotherapy and deteriorating clinical condition, she began the therapy with ALK inhibitors. In total, the patient was treated with crizotinib, alectinib, and lorlatinib. As a result, after over 4 years since the initial diagnosis, she is still alive with significantly improved clinical condition and quality of life. This paper demonstrates the clinical benefits of sequential therapy of ALK inhibitors and an exceptionally long response to lorlatinib, a third-generation tyrosine kinase inhibitor.

Thoracic epithelioid inflammatory myofibroblastic sarcoma: a rare and aggressive disease with case report and literature review

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare subtype of inflammatory myofibroblastic tumor, characterized to be an aggressive disease with high frequency of ALK rearrangement, rapid recurrence, and poor prognosis. Primary EIMS of thoracic origin is rarely observed. Herein, we described a case of 28-year-old female developed primary EIMS in the anterior mediastinum with hepatic metastasis. The EIMS displayed sheet-like growth of epithelioid and spindle cells with enlarged nuclei, abundant and eosinophilic cytoplasm, and infiltration of inflammatory cells. Immunohistochemical staining revealed positive expression of ALK in the nuclear membrane, and ALK rearrangement was identified by polymerase chain reaction assay. Alectinib showed partial response, and achieved a meaningful survival benefit for four months. Based on this case report and literature review, ALK inhibitor reveals promising activity on the rare but aggressive EIMS. Awareness of EIMS in thoracic disease and its clinicopathological features is essential to avoid erroneous diagnosis.

Epithelioid inflammatory myofibroblastic sarcoma treated with Alectinib: a case report and literature review

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an extremely rare and aggressive form of inflammatory myofibroblastic tumor. Clinically, it has a high risk of relapse and peripheral organ infiltration, and it responds poorly to conventional chemotherapy. Anaplastic lymphoma kinase (ALK) inhibitors are currently the most effective targeted therapy for EIMS. This report discusses a typical case of abdominal EIMS in a 43-year-old woman. The tumors recurred rapidly within one month after surgery. Alectinib was promptly administered upon diagnosis. However, the patient developed a severe allergic reaction to the medication. After a comprehensive assessment and symptomatic treatment, her condition stabilized, leading to a favorable prognosis. This study summarizes cases of abdominal EIMS, highlights the successful use of Alectinib for treatment, and discusses the management of medication-related complications.

Primary epithelioid inflammatory myofibroblastic sarcoma of the brain with EML4::ALK fusion mimicking intra-axial glioma: a case report and brief literature review

An aggressive subtype of inflammatory myofibroblastic tumor, epithelioid inflammatory myofibroblastic sarcoma occurs primarily inside the abdominal cavity, followed by a pulmonary localization. Most harbor anaplastic lymphoma kinase (ALK) gene rearrangements, with RANBP2 and RRBP1 among the well-documented fusion partners. We report the second case of primary epithelioid inflammatory myofibroblastic sarcoma of the brain, with a well-known EML4::ALK fusion. The case is notable for its intra-axial presentation that clinico-radiologically mimicked glioma.

ALK-Rearranged Epithelioid Mesenchymal Neoplasm: Expanding the Spectrum of Tyrosine Kinase-Altered Mesenchymal Tumors

The anaplastic lymphoma kinase (ALK) gene encodes a receptor tyrosine kinase, and fusions involving this gene have been reported in a variety of mesenchymal neoplasms. ALK-altered tumors with epithelioid morphology have been described in epithelioid inflammatory myofibroblastic sarcoma and epithelioid fibrous histiocytoma. Herein, we describe the clinicopathologic features of 7 ALK-rearranged mesenchymal tumors with epithelioid morphology occurring predominately in the pediatric population. Tumors occurred in 4 females and 3 males with an age ranging from 1 month to 28 years. Five tumors were superficial and solitary, while 1 presented with multiple peritoneal/omental nodules, and 1 presented as a large mediastinal mass. Morphologically, all tumors comprised epithelioid cells arranged in sheets, anastomosing cords, or small clusters embedded in a myxohyaline stroma. The cells had slightly variably sized ovoid nuclei with moderately prominent nucleoli and abundant eosinophilic cytoplasm. Four cases had sparse mitotic figures without necrosis. The remaining 3 tumors (2 deep and 1 superficial) had more than 10 mitoses per 10 high-power fields as well as foci of necrosis. ALK fusions were identified in all cases. The fusion partners included HMBOX1 (n = 1), VCL (n = 1), PRRC2B (n = 1), MYH10 (n = 1), STRN (n = 1), and EML4 (n = 2). One tumor recurred locally 2 years after initial resection; 1 patient had widely metastatic disease (mediastinal tumor). At the time of last follow-up (n = 6), 4 patients were alive without evidence of disease, 1 died due to complications of therapy (peritoneal tumor), and 1 was alive with disease. Our findings expand the spectrum of ALK-rearranged mesenchymal tumors. Our cases predominately occurred in older children and mainly exhibited epithelioid to round cell morphology, as opposed to spindle cell morphology. We also show that tumors in a deep location with higher-grade features follow a more aggressive clinical course.

Epithelioid Inflammatory Myofibroblastic Sarcoma With Poor Response to Crizotinib: A Case Report

Introduction

Epithelioid type inflammatory myofibroblastic sarcoma (EIMS) is a subtype of inflammatory myofibroblastic tumor (IMT). It consists of round or epithelioid cells, and almost all types of EIMS contain rearrangements of the anaplastic lymphoma kinase (ALK) gene.

Case presentation

We describe a 20-year-old female presenting with abdominal pain and a rapidly growing intraabdominal mass who underwent surgical tumor resection. She was diagnosed with EIMS. ALK and ki-67 expressions were detected in immunohistochemistry assessment. She was started with Crizotinib 200 mg twice a day, and chemotherapy was also initiated due to the recurrence of the disease 4 months after the initial treatment. She was unresponsive to all the medical regimens and died in 8 months.

Conclusion

Approach to patients with EIMS is really challenging in terms of both diagnosis and treatment. Patients with combined surgical and non-surgical treatment regimen were seen to have a more favorable outcome in some EIMS cases. Therefore, it is essential to implement a multidisciplinary approach to diagnose and treat patients suspicious of EIMS.

Epithelioid inflammatory myofibroblastic sarcoma: a case report and brief literature review

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare variant of the inflammatory myofibroblastic tumor, characterized by more aggressive clinical course and nuclear membrane staining of anaplastic lymphoma kinase (ALK) with ALK rearrangement. An elderly male came to the clinic because of an accidental abdominal mass. Abdominal and pelvic enhanced CT revealed a tumor apparently orginated from mesenchymal tissue. Subsequently, the abdominal mass and multiple organ resection was performed, and the mass was pathologically confirmed as EIMS. The patient developed Clavien-Dindo Grade III postoperative complications and was discharged after his condition improved. He received doxorubicin monotherapy after operation, but only one cycle was administered due to severe vomiting. The follow-up of 5 months after operation showed no evidence of recurrence. Given the rarity of EIMS, and ALk inhibitors have a long and robust effect on patients with ALK gene tumors, it is very important for clinicians to be familiar with the clinicopathological features of EIMS, which will contribute to the accurate diagnosis of EIMS and reduce misdiagnosis.

A Novel CASC15-ALK and TFG-ROS1 Fusion Observed in Uterine Inflammatory Myofibroblastic Tumor

The majority of inflammatory myofibroblastic tumors (IMTs) in the gynecologic tract occur in the uterine corpus and harbor anaplastic lymphoma kinase ( ALK ) rearrangement. Herein, we report 1 uterine IMT case with a novel fusion involving ALK and 1 uterine IMT case with ROS1 rearrangement. The ages of the patients were 56 and 57 yr, respectively. The tumor size was 10.0 and 8.0 cm, respectively. Both patients had stage IB disease. Histologically, the 2 IMT cases had classic morphologic features and predominantly comprised bland spindle cells with hypercellular (fascicular/storiform) and hypocellular (myxoid rich) areas admixed with variably prominent lymphoplasmacytic infiltration. Immunohistochemically, the ALK -rearranged case was positive for ALK , and the ROS1 -rearranged case was positive for ROS1 . Both cases were diffusely positive for desmin. The tumor cells were variably positive for estrogen receptor (1/2 cases, 50.0%) and progesterone receptor (1/2 cases, 50.0%). Targeted RNA sequencing revealed one case each with either a novel CASC15-ALK or TFG-ROS 1 fusion. We identified a novel ALK fusion partner CASC15 in IMT and described the first uterine IMT with a TFG-ROS1 fusion. This study improves our understanding of molecular events in IMT.

Epithelioid inflammatory myofibroblastic sarcoma arising in the maxilla: first reported case in the jaws

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare variant of inflammatory myofibroblastic tumors located mostly in the intra-abdominal region. Herein, we present a case of a 32-year-old male with a lobulated growth in the right maxilla. Radiology revealed a solitary osteolytic lesion with an irregular margin, causing buccal and palatal cortex erosion. Histopathology revealed a tumor composed of spindle-shaped fascicles that blend into sheets of round to ovoid-shaped epithelioid cells, areas of myxoid changes, and necrosis. Tumor cells showed a moderate amount of eosinophilic cytoplasm, large vesicular nuclei with coarse chromatin, nuclear pleomorphism, and increased mitoses. Tumor cells were immunopositive for ALK-1, focal positivity for smooth muscle actin, panCK, epithelial membrane antigen, and immunonegativity for CD 30, desmin, CD34, and STAT6. P53 showed a wild-type staining pattern, and INI-1 expression was retained. The Ki-67 proliferative index was 22%. To the best of our knowledge, this is the first case of EIMS occurring in the maxilla.

Case report: Epithelioid inflammatory myofibroblastic sarcoma treated with an ALK TKI ensartinib

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive variant of inflammatory myofibroblastic tumor (IMT) and has a poor prognosis. EIMS is characterized by epithelioid morphology, neutrophilic infiltrate and specific fusion partners of anaplastic lymphoma kinase (ALK). Despite no standard therapy for EIMS, ALK tyrosine kinase inhibitors (TKIs) are recommended for these tumors. The present case describes an abdominal mass that presented in a 31-year-old male. The patient suffered from recurrence and multiple metastases 2 months after surgery. Ensartinib was administered and RANBP2-ALK fusion was detected. A partial response has been observed for 4 months and there has been no recurrence. This study provided a successful case with sustained response of targeted therapy.

Inflammatory Myofibroblastic Tumour: State of the Art

Simple Summary

Among sarcomas, which are rare cancers, inflammatory myofibroblastic tumors are extremely rare. Unlike other subtypes, this is a largely oncogene-driven neoplasia, and early gene rearrangement identification is important for accurate advanced stage treatment. In this manuscript, we review the clinicopathologic characteristics of this ultra-rare entity, as well as the current treatment landscape, with a particular focus on opportunities provided by tyrosine kinase inhibitors (TKIs).

Abstract

An inflammatory myofibroblastic tumor (IMT) is a neoplasm composed of myofibroblastic and fibroblastic spindle cells accompanied by inflammatory cells, including lymphocytes and eosinophils. It is an ultra-rare tumor, the optimal management of which remains to be defined. Surgery is the treatment of choice for localized tumors. The treatment of advanced disease is not precisely defined. Chemotherapy regimens result in an overall response rate of approximately 50% based on retrospective data. The latest pathophysiological data highlight the role played by tyrosine kinase fusion genes in IMT proliferation. Anaplast lymphoma kinase (ALK) oncogenic activation mechanisms have been characterized in approximately 80% of IMTs. In this context, data regarding targeted therapies are most important. The aims of this article are to review the latest published data on the use of systematic therapy, particularly the use of molecular targeted therapy, and to publish an additional case of an IMT with Ran-binding protein 2 (RANPB2)-ALK fusion showing a long response to a tyrosine kinase inhibitor.