Primary Cutaneous Epithelioid Inflammatory Myofibroblastic Sarcoma Harboring RANBP2-ALK Fusion: Report of an Exceptional Case

PDGFRA::USP8 Fusion in a Cutaneous Inflammatory Myofibroblastic Tumor, Highlighting Genetic Pleiotropy of Kinase Gene Fusions in Soft Tissue Neoplasms

PDGFRA

USP8 fusions have recently been described in neoplasms in the provisional category of calcified chondroid mesenchymal neoplasm (CCMN). Here, we describe a cutaneous inflammatory myofibroblastic tumor (IMT) on the upper leg of a 24-year-old male harboring the same fusion product. The tumor showed a morphology typical of IMT, including a concomitant inflammatory infiltrate; in addition, there was strong immunohistochemical PDGFRα overexpression. Methylation profiling (Sarcoma classifier v12.2) was consistent with IMT (calibrated score 0.99). Herein, we review other soft tissue tumors with PDGFRA fusions, emphasizing PDGFRA::USP8 fusions, further highlighting the genetic pleiotropy of kinase gene fusions in soft tissue tumors. In addition, this case expands the landscape of kinase fusions in IMT, presented by an extremely rare cutaneous IMT.

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.

Epithelioid Inflammatory Myofibroblastic Sarcoma: A Report of a Rare Case

Epithelioid inflammatory myofibroblastic sarcoma (EIMS), a variant of inflammatory myofibroblastic tumor (IMT), is a rare malignant tumor commonly associated with anaplastic lymphoma kinase (ALK) gene fusions and is aggressive in nature with local recurrence. Here, we report a case of a 23-year-old female who presented with a cough and, upon investigations, was found to have a mass in the left upper lobe of the lung detected by chest computed tomography (CT). Biopsy revealed EIMS with ALK and desmin protein expression. The patient underwent a lobectomy via video-assisted thoracoscopic surgery (VATS). The postoperative period was uneventful.

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.

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.