The Ewing family of tumors (EFTs) is a group of small cell sarcomas including Ewing sarcoma of the bone, extra osseous Ewing tumors, and primitive neuroectodermal tumors. They are rare cancers, usually diagnosed in peoples' twenties. The sarcoma of bone is the most common of the variants. All forms are predisposed to metastasis and have had historically high rates of mortality. The family of tumors shares a common translocation mutation of the EWS gene on chromosome 22 to an ETS-type gene, most commonly the FLI1 gene.[1] EFTs are highly malignant, with 5-year survival for patients with metastatic disease at 20%. The current standard of care includes resection, radiation, and chemotherapy.[2]
Genetic and demographic predisposition
editEwing’s sarcoma is most common in Caucasians and typically diagnosed during the first several decades of life, most often in someone’s teens. The cancer also affects males at twice the rate compared to females.[1]
Despite EFTs appearing more often in younger patients, they have not been linked to any common cancer predisposing syndromes, such as Li-Fraumeni Syndrome. EFTs have also not been shown to correlate with any environmental risk factor.[3] The defining genetic mutation of EFTs is the translocation of EWS gene located on chromosome 22 to an ETS-type gene, most often FLI1. Other potential fusion genes include ERG, ETV1, E1A-F, or FEV.[4]
Types
editThe Ewing Family of Tumors are small cell sarcomas most commonly occurring within the bone, but may also occur within soft tissues or as a primitive neuroendocrine tumor.
Ewing's sarcoma of bone
editEwing’s sarcoma of bone is the most common of the EFTs and tends to occur in the trunk and long bones. The cancer most often occurs in the shaft, or diaphysis, of bones, as compared to other common bone cancers. The most common presenting symptom is pain in the bone, and the initial diagnostic step is imaging, often both MRI and radiograph. Due to the high chance of metastasis, full body PET/CT is often performed to look for cancer spread. Confirming diagnosis of Ewing’s sarcoma requires biopsy and genetic testing. The current practice for treatment is first neoadjuvant radiation to shrink the cancer, resection, and follow up chemotherapy.[1][5]
Extra-osseous Ewing's sarcoma
editExtra-osseous Ewing’s sarcoma accounts for roughly 20% of Ewing’s sarcoma cases, and most commonly occurs in the glutes, shoulders, and arms. The presentation is nonspecific, with most patients first reporting a painful mass. Initial workup is similar to Ewing’s sarcoma of bone, beginning with imaging. However, ultrasound is often used in conjunction with CT and MRI. Biopsy is again required to confirm diagnosis. Treatment also consists of surgical removal followed by chemotherapy, however patients seem to do better overall when compared to Ewing’s sarcoma of the bone.[6][7]
Primitive Neuroectodermal Tumor (PNETs)
editPrimitive neuroendocrine tumors are rare forms of EFTs that originate from neuroendocrine cells, with the differentiation varying from tumor to tumor. PNETs were first discovered in peripheral nerves and considered distinct from EFTs, until genetic studies showed the same translocation of EWS-FLI1 in PNETs. PNETs and Ewing’s sarcoma are described as appearing on the same histologic spectrum.[8][9] Treatment of PNETs is the same as extra-osseous Ewing’s sarcoma, with resection of the whole tumor alongside chemotherapy and radiation. Outcomes however are poor as PNET remains an aggressive cancer as a member of the Ewing Family of Tumors.[9]
References
edit- ^ a b c Iwamoto Y (February 2007). "Diagnosis and treatment of Ewing's sarcoma". Japanese Journal of Clinical Oncology. 37 (2): 79–89. doi:10.1093/jjco/hyl142. PMID 17272319.
- ^ Yu H, Ge Y, Guo L, Huang L (January 2017). "Potential approaches to the treatment of Ewing's sarcoma". Oncotarget. 8 (3): 5523–5539. doi:10.18632/oncotarget.12566. PMC 5354928. PMID 27740934.
- ^ Gargallo P, Yáñez Y, Juan A, Segura V, Balaguer J, Torres B, et al. (October 2020). "Review: Ewing Sarcoma Predisposition". Pathology & Oncology Research. 26 (4): 2057–2066. doi:10.1007/s12253-019-00765-3. PMID 31656020. S2CID 204907655.
- ^ Baldauf MC, Orth MF, Dallmayer M, Marchetto A, Gerke JS, Rubio RA, et al. (January 2018). "Robust diagnosis of Ewing sarcoma by immunohistochemical detection of super-enhancer-driven EWSR1-ETS targets". Oncotarget. 9 (2): 1587–1601. doi:10.18632/oncotarget.20098. PMC 5788584. PMID 29416716.
- ^ Zöllner SK, Amatruda JF, Bauer S, Collaud S, de Álava E, DuBois SG, et al. (April 2021). "Ewing Sarcoma-Diagnosis, Treatment, Clinical Challenges and Future Perspectives". Journal of Clinical Medicine. 10 (8): 1685. doi:10.3390/jcm10081685. PMC 8071040. PMID 33919988.
- ^ Abboud A, Masrouha K, Saliba M, Haidar R, Saab R, Khoury N, et al. (May 2021). "Extraskeletal Ewing sarcoma: Diagnosis, management and prognosis". Oncology Letters. 21 (5): 354. doi:10.3892/ol.2021.12615. PMC 7967932. PMID 33747211.
- ^ Galyfos G, Karantzikos GA, Kavouras N, Sianou A, Palogos K, Filis K (February 2016). "Extraosseous Ewing Sarcoma: Diagnosis, Prognosis and Optimal Management". The Indian Journal of Surgery. 78 (1): 49–53. doi:10.1007/s12262-015-1399-0. PMC 4848231. PMID 27186040.
- ^ Bosman FT (2018-07-27). "Book review—Rosai and Ackerman's surgical pathology-2 volume set, 11th edition". Virchows Archiv. 473 (3): 389–390. doi:10.1007/s00428-018-2421-2. ISSN 0945-6317. S2CID 51726143.
- ^ a b Patel D, Nandu NS, Reddy A (April 2020). "Extraosseus [sic] Ewing's Sarcoma in Pancreas: A Review". Cureus. 12 (4): e7505. doi:10.7759/cureus.7505. PMC 7195206. PMID 32373408.
External links
edit- Cancer.Net: Ewing Family of Tumors, Childhood
- Ewing family of tumors entry in the public domain NCI Dictionary of Cancer Terms
This article incorporates public domain material from Dictionary of Cancer Terms. U.S. National Cancer Institute.