Primary Epithelioid Sarcoma of Frontotemporal Scalp: a Rare Case Report with Recent Literature Review

Epithelioid sarcoma (ES) is a very rare and aggressive mesenchymal sarcoma subtype which represents less than 1% of soft tissue sarcomas (STS). According to the origin of the site, there are two types of ES: distal-type epithelioid sarcoma and proximal-type epithelioid sarcoma. The clinical diagnosis of ES mainly is confirmed by histopathology examination followed by immunohistochemistry. Radical excisional surgery is the best treatment option for epithelioid sarcoma. According to TNM staging, the treatment option will vary from surgery to surgery accompanied with radiotherapy and chemotherapy. Here in, we presented a 36-year-old man had non-healing ulcer in left frontotemporal scalp extending to involve left orbit. Histopathological confirmed epithelioid sarcoma. Magnetic Resonance Imaging (MRI) of Head and Neck revealed that there was mass in left frontotemporal scalp measuring 6.7 X 5.7 X 2.6 cm extending to zygomatic region and left orbit D/D malignant mass/sarcoma with bilateral (B/L) sinusitis. After that patient undergone for Wide Local excision (WLE) surgery on 11 th September 2022. Adjuvant Radiation Therapy (RT) 6000 cGy radiation dose in 30 fractions (#) which was 200 cGy per fraction (#) were given during 22 nd September to 10 th November 2022 due to local advancement of disease. Patient was asked to follow up after 6 weeks after completion of RT. After 6 weeks of surgery, the patient was undergone for MRI and report revealed normal study.


Introduction
Epithelioid sarcoma (ES) is a very rare and brutal soft tissue sarcoma first portrayed by Enzinger in 1970, which may be proximal or distal types. 1 ES is a malignant mesenchymal neoplasm that exhibits epithelioid cytomorphology and a predominantly epithelial phenotype.The neoplastic cells in the proximal subtype tend to exhibit prominent malignant features including moderate nuclear atypia with prominent nucleoli and are associated with a poorer prognosis than the distal subtype. 2 ES of the scalp as a primary site of origin is a rare occurrence and hence possesses a challenge in early diagnosis and timely intervention.In addition, there is not specific treatment management for ES of the scalp due to very few cases were reported and limited studies are accessible on the role of chemotherapy.Therefore, even in the current period, radical wide surgical resection (WLE) with adjuvant radiation therapy remains the basis of treatment. 3ES has a far above the ground predisposition for local recurrence, lymph nodes invasion, and distant metastasis, especially when it involves the lungs. 4ny research studies articles have reported on epithelioid sarcoma survival rates through the years.Due to rare occurrences of the disease, the numbers show a discrepancy and significantly.Five-year survival and ten-year survival rate for patients with epithelioid sarcoma are approximately 50-70% and 42-55% respectively. 5Our case was a survival case from ES in the scalp.There were 14 primary studies that have been reported ES in the scalp till the date.We did a retrospective analysis and reviewed all the reported studies.

Case Report
Here in, we presented a 36-year-old man had nonhealing ulcer in left frontotemporal scalp extending to involve left orbit.Histopathological features and immunohistochemistry were confirmed that it was proximal type epithelioid sarcoma.Histopathology examination revealed that pleomorphic dermal infiltrate consistent within epithelioid sarcoma.Magnetic Resonance Imaging (MRI) of Head and Neck revealed that there was mass in left frontotemporal scalp measuring 6.7 X 5.7 X 2.6 cm extending to zygomatic region and left orbit D/D malignant mass/sarcoma with bilateral (B/L) sinusitis.GradeIII, left temporal region, 6 X 6 X 2.5 cm, DOI 1.8 cm, LVSI was not identified.PNI present, margins were uninvolved, 0.1 cm from closest margin, Zygomatic bone was involved by tumor and eyebrow with eyelid was also involved with tumor however epidermis free from tumor (LN0/40, pT4aN0).Adjuvant Radiation Therapy (RT) 6000 cGy radiation dose in 30 fractions (#) which was 200 cGy per fraction (#) were given during 22 nd September to 10 th November 2022.Patient was asked to follow up after 6 weeks after completion of RT.After 6 weeks of radiation therapy (RT), the patient undergone for MRI of Head and Neck.MRI examination revealed no residual or recurrent mass seen in the post operative bed.There was Myocutaneous free flap in the surgical bed in left frontotemporal scalp extending to zygomatic region and covering entire left orbit (which was exenterated) with post RT changes.There was B/L maxillary left ethmoid sinusitis.Computed Tomography (CT) scan Chest was also done to examine lung metastases and revealed that there were no lungs metastases.

Discussion
There are many assumption concerning the derivation and tumorigenesis of epithelioid sarcoma (ES).It has been projected that ES is a mesenchymal carcinoma originated from prehistoric mesenchymal or myofibroblast cells. 1 There is another hypothesis squabble that ES may be originate from naive synovial cells and correspond to a modification of synovial sarcoma. 19Both subtypes (proximal and distal) of ES influence patients of a broad age variety which is also summarized in table 1. ES is in attendance obvious malignant histologic features, including a high mitotic index, necrosis, and invasiveness.The age at the diagnosis of ES which is originated at scalp ranges from 1 year to 80-years, and the average age are28 years.The propensity for local recurrence and distal metastasis is higher in ES of the scalp and is usually correlated with bone invasion, indicating its distinction from ES of other locations.ES occurring in the head and neck are supposed to be differentiated from other epithelioid tumors by INI stains. 20e clinical, pathological and other details of previous published case studies and our present case study are summarized (Table 1).In our study, we also summarized literatures review.A total of 15 case studies are included in this literature review including our study.The male female proportion is approximately 2.7:1.The 15 cases studies of scalp ES including our case study preponderated by epithelioid tumor cell morphology.Prognosis of scalp ES is dependent upon various factors including TNM staging of tumor i.e. tumor size, bony erosion, adjacent organ involvement, lymph lodes involvements and distance metastases.The prognosis of scalp ES is correlated with a poor prognosis and all relapsed cases exhibited bone erosion.Necrosis exists in up to 70% of the cases and is usually associated with central degeneration.Most cases exhibit a dominated epithelioid morphology in the dermis and subcutaneous tissue with ulcer and lymphatic vascular invasion.Granuloma-like features, calcification and bone formation occasionally occur.Approximately, 60 % of cases were recovered from disease including our case study in literature review of all 15 cases.This may be due to external appearance and diagnosed earlier.
Treatment protocol is still not consistent, but radical surgery is the best option for ES scalp.Radiotherapy is given for local invasion of disease.In some cases, chemotherapy is also given but it is not significantly approachable.Many research studies articles have reported on epithelioid sarcoma survival rates through the years.Due to rare occurrences of the disease, the numbers show a discrepancy and significantly.Five-year survival and ten-year survival rate for patients with epithelioid sarcoma are approximately 50-70% and 42-55% respectively. 5Our case was a survival case from ES in the scalp.

Conclusion
To our knowledge, this report describes a unique clinical case and contains the largest descriptive analysis of reported cases of primary non-metastatic scalp ES.We presented the initial clinical findings and treatment course for a male patient diagnosed with ES of the left Fronto parietal scalp, stage pT2 N0 M0.Based on the previously reported clinical outcomes for patients with primary scalp ES.In prior reported clinical outcomes for scalp ES cases, we feel it is reasonable to consider surgical resection followed by postoperative external beam radiotherapy for localized scalp ES.Future research is still needed for this rare malignancy and clinical presentation.

Figure 1 :
Figure 1: Pre-treated Magnetic Resonance Imaging (MRI) scan of Face and Neck revealed that there was mass in left frontotemporal scalp measuring 6.7 X 5.7 X 2.6 cm extending to zygomatic region and left orbit D/D malignant mass/sarcoma with bilateral (B/L) sinusitis.

Figure
Figure 2Post treated Magnetic Resonance Imaging (MRI) scan of Face and Neck revealed no residual or recurrent mass seen in post-operative bed.There was myocutaneous free flap in the surgical bed in left frontotemporal scalp extending to zygomatic region and covering entire left orbit (which was exenterated) with post RT changes.

Figure 3 :
Figure 3: Post Treated photograph of patient.