Deep Soft Tissue Research Articles

A large femoral primary cutaneous Ewing's sarcoma in a 35-year-old woman: Case report.

IntroductionExtraskeletal Ewing's sarcoma is a rare malignant tumor of mesenchymal origin, which is histologically similar to primary osseous Ewing's sarcoma. It has been well described in deep soft tissues. However, location in cutaneous or subcutaneous tissue has rarely been reported. Being seen principally in children, it can be seen, rarely, in old men.Case presentationWe present a case of large primary cutaneous Ewing sarcoma within the left thigh of a 35-year-old woman, without osseous involvement. Physical examination. Histologically, it was a small round cell tumor that marked strongly for CD99. The diagnosis of cutaneous Ewing sarcoma was performed.DiscussionThe things that distinguish our case are that it is the first case in Syria, in addition to the size of the large tumor with diameters of 15 × 20 cm, and it is in a 35-year-old woman.ConclusionEwing sarcoma is a rare malignant small round cell tumor of the skin and subcutaneous tissue. It should be differentiated from other cutaneous neoplasms composed of small round cells.

Laparoscopic excision for multiple intra-abdominal juvenile fibrosarcoma: A case report.

Introduction and importanceFibrosarcoma is a rare malignant tumor comprising spindle-shaped fibroblasts exhibiting variable collagen production. Adult-type fibrosarcoma (AFS) mainly occurs in people aged between 30 and 80 years, primarily in the deep soft tissues of the trunk, neck, and extremities, especially in areas surrounding bones. Juvenile fibrosarcoma(JFS) is a type of AFS that occurs in adolescents and rarely develops in the abdominal cavity.Case presentationA 13-year-old girl presented with right upper quadrant pain for 5 days. Abdomen and pelvis computed tomography showed a 12 × 6-cm, ill-defined, lobulated, solid, cystic mass in the abdominal cavity. On laparoscopy, there were two masses in the abdominal cavity. One abutted the stomach and severely adhered to the gallbladder. The second mass was located between the transverse colon and duodenum, and it was surrounded by the omentum. The tissues surrounding the masses were finely dissected, and the two masses were excised completely. The patient was discharged without complications on post-operative day 7.Clinical discussionJFS, AFS in adolescents, is a rare malignant tumor. And there have been no reported cases of multiple JFS in abdominal cavity. Surgical excision is the gold standard of treatment for localized AFS, and the laparoscopic approach for minimal tumor handling is beneficial.ConclusionWe describe a rare case of multiple intra-abdominal juvenile fibrosarcoma, managed through laparoscopic surgery.

Localized Angiosarcoma, Not One Disease: A Retrospective Single-Center Study on Prognosis Depending on the Primary Site and Etiology.

Background Angiosarcomas are rare and heterogeneous tumors with poor prognosis. The clinical subtypes are classified depending on the primary site and etiology. Methods We conducted a retrospective, monocentric study of 136 patients with localized AS between May 1985 and November 2018. Overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) were estimated using the Kaplan–Meier method. To identify prognostic factors, univariate and multivariate analyses were performed based on Cox regressions. Results The median age was 67 years (19–72.8 years). Primary sites were cutaneous (27.2%), breast (38.2%), and deep soft tissue (34.6%). The majority was primary angiosarcomas (55.9%) followed by postradiation (40.4%) and chronic lymphedema angiosarcomas (2.9%). Prognosis significantly differed depending on the primary site and etiology. Shortest median OS and MFS were observed in deep soft tissue angiosarcomas, whereas cutaneous angiosarcomas, angiosarcomas of the breast, and radiation-associated angiosarcomas displayed worse median LRFS. Univariate analyses showed better OS for tumor size <10 cm (p = 0.009), negative surgical margins (p = 0.021), and negative lymph node status (p = 0.007). LRFS and MFS were longer for tumor size <10 cm (p = 0.012 and p = 0.013). In multivariate analyses, age <70 years was the only independent positive prognostic factor for OS in all subgroups. For LRFS, secondary AS of the breast was a negative prognostic factor (HR: 2.35; p = 0.035). Conclusions Different behaviors and prognoses depending on the primary site and etiology should be considered for the treatment of this heterogeneous disease. In cutaneous angiosarcomas of the head/neck and postradiation angiosarcomas of the breast, local recurrence seems to have a crucial impact on OS. Therefore, improved local therapies and local tumor staging may have to be implemented. However, in deep soft tissue angiosarcomas, distant recurrence seems to have a major influence on prognosis, which indicates a benefit of additional perioperative chemotherapy.

A case of peripancreatic plexiform schwannoma

BackgroundPlexiform schwannoma is one of the least common variants of schwannoma, accounting for only 5% of all schwannoma cases. It generally occurs in the skin and subcutaneous tissues and is uncommon in deep soft tissue or viscera. We present an extremely rare case of plexiform schwannoma arising from the peripancreatic plexus.Case presentationA 29-year-old man presented with hyperglycemia detected during a medical checkup. He was diagnosed with type 1 diabetes based on the clinical findings and laboratory tests. During the diagnostic process for diabetes, a 2.5 cm mass was incidentally detected in the pancreas by abdominal ultrasound. Contrast-enhanced computed tomography revealed a mass that was gradually enhanced at the body and tail of the pancreas. Magnetic resonance imaging revealed low signal intensity of the mass on T1-weighted images and high signal intensity on T2-weighted and diffusion-weighted images. Magnetic resonance cholangiopancreatography showed no abnormal findings in the main pancreatic duct. Endoscopic ultrasonography (EUS) showed a lobulated, low-echoic mass with a clear boundary. EUS-guided fine needle biopsy was performed, and spindle-shaped cells that were diffusely immunopositive for S-100 and negative for c-kit and desmin were detected, resulting in a diagnosis of a neurogenic tumor arising from the pancreas or the peripancreatic nerve plexus. The patient underwent laparoscopic spleen-preserving distal pancreatectomy. Although the tumor was connected to the splenic plexus, the splenic artery could be divided along its adventitial plane. Macroscopic findings of the excised tumor consisted of multiple yellowish-white nodules, and its histopathological features were consistent with plexiform schwannoma. There was no pancreatic tissue on the dorsal surface of the tumor, which suggested that the tumor arose from the peripancreatic nerve plexus.ConclusionsThe findings documented herein can aid in the differential diagnosis of peripancreatic schwannoma and in planning appropriate treatment.

Intra-articular leiomyoma of the knee mimicking a ganglion cyst in a child: A case report and review of literature.

Introduction and importanceAngioleiomyoma is a rare benign soft tissue tumor of smooth muscle getting its origin from the muscular layer of vessel walls. The localized type of leiomyoma occurs on the skin, deep soft tissues, in the genitourinary, gastrointestinal, and respiratory tracts.Case presentationWe report a case of a 16-year-old patient who presented with an intra-articular leiomyoma developed in the anterior cruciate ligament and treated with arthroscopy.Clinical discussionAngioleiomyoma can occur anywhere in the body and is most often seen in the extremities, particularly the lower limbs, but is very rare in the knee joint. Angioleiomyoma should be included in the differential diagnosis of nodular lesions mimicking loose body, such as lipomas, inclusion cysts, ganglion, pigmented villonodular synovitis (PVNS), fibroma, nodular synovitis, hemangioma, synovial sarcoma, myopericytoma, leiomyosarcomas, glomus tumor.ConclusionAngioleiomyoma related to the cruciate ligaments of the knee should be considered in the differential diagnosis of a painful knee especially when associated with a decreased of range of motion of knee. The arthroscopic debridement should be considered the treatment of choice in order to reliably restore active ROM.

Synovial Sarcoma of the Extremities: A Literature Review

Synovial sarcoma (SS) is a rare and highly malignant tumor and a type of soft tissue sarcoma (STS), for which survival has not improved significantly in recent years. Synovial sarcomas occur mostly in adolescents and young adults (15–35 years old), usually affecting the deep soft tissues near the large joints of the extremities, with males being at a slightly higher risk. Despite its name, synovial sarcoma is neither related to the synovial tissues that are a part of the joints, i.e., the synovium, nor does it express synovial markers; however, the periarticular synovial sarcomas can spread as a secondary tumor to the joint capsule. SS was initially described as a biphasic neoplasm comprising of both epithelial and uniform spindle cell components. Synovial sarcoma is characterized by the presence of the pathognomonic t (X; 18) (p11.2; q11.2) translocation, involving a fusion of the SS18 (formerly SYT) gene on chromosome 18 to one of the synovial sarcoma X (SSX) genes on chromosome X (usually SSX1 or SSX2), which is seen in more than 90% of SSs and results in the formation of SS18-SSX fusion oncogenes.

Low‐grade fibromyxoid sarcoma arising from the lung: A case report

Low‐grade fibromyxoid sarcoma (LGFMS) is a rare sarcoma subtype that most commonly arises in young adults. This tumor typically presents in the deep soft tissues of the proximal extremities or trunk as a painless mass. Although the most common site of LGFMS metastasis is the lung, it is rarely the primary site. Here, we report a case of primary pulmonary LGFMS. A 22‐year‐old asymptomatic man was referred to our hospital for investigation of a lung mass that had been discovered incidentally. Computed tomography (CT) showed a well‐defined mass 4.0 cm in diameter in the upper lobe of the right lung. Malignancy was suggested by focal uptake of 18F‐fluorodeoxyglucose positron‐emission tomography (18‐FDG‐PET). Following surgery, postoperative histological analysis of the resected specimen demonstrated LGFMS based on histological and immunohistological findings. In particular, mucin 4 showed diffuse positivity in the spindle‐shaped tumor cells. In conclusion, LGFMS can arise in the lungs, and physicians should consider this entity as a differential diagnosis for solitary lung mass in young adults.

Sarcoma fibromixoide de bajo grado con metástasis pulmonares. Reporte de un caso raro

Background Low-grade fibromyxoid sarcoma is a very rare tumor that tends to develop in deep soft tissues of young adults and has the potential for local recurrence and distant metastasis. Clinical case We present the case of a 36-year-old man with a low-grade fibromyxoid sarcoma in the right shoulder, which was initially reported as a 4-year-old tumor, undergoing extensive resection with a histopathological report of low-grade fibromyxoid sarcoma, whose deep surgical edge was in bony contact. A simple and contrasted axial tomography was performed where an 8 mm left lung lesion was observed in the upper lobe lower lingular segment of heterogeneous content, hyperdense with contrast medium reinforcement. Left lateral thoracotomy is performed for metastasectomy and pathology corroborates the diagnosis of metastasis from fibromyxoid sarcoma. Conclusion Low histological fibromyxoid sarcoma is a very rare tumor that must be differentiated from other soft tissue tumors. Recurrences and metastases are reported, despite short or prolonged disease-free periods of up to 50 years, so patients with a history of this tumor should be followed up.

Biology and Management of Dedifferentiated Liposarcoma: State of the Art and Perspectives.

Dedifferentiated liposarcoma (DDL) is defined as the transition from well-differentiated liposarcoma (WDL)/atypical lipomatous tumor (ALT) to non-lipogenic sarcoma, which arises mostly in the retroperitoneum and deep soft tissue of proximal extremities. It is characterized by a supernumerary ring and giant marker chromosomes, both of which contain amplified sequences of 12q13-15 including murine double minute 2 (MDM2) and cyclin-dependent kinase 4 (CDK4) cell cycle oncogenes. Detection of MDM2 (and/or CDK4) amplification serves to distinguish DDL from other undifferentiated sarcomas. Recently, CTDSP1/2-DNM3OS fusion genes have been identified in a subset of DDL. However, the genetic events associated with dedifferentiation of WDL/ALT remain to be clarified. The standard treatment for localized DDL is surgery, with or without radiotherapy. In advanced disease, the standard first-line therapy is an anthracycline-based regimen, with either single-agent anthracycline or anthracycline in combination with the alkylating agent ifosfamide. Unfortunately, this regimen has not necessarily led to a satisfactory clinical outcome. Recent advances in the understanding of the pathogenesis of DDL may allow for the development of more-effective innovative therapeutic strategies. This review provides an overview of the current knowledge on the clinical presentation, pathogenesis, histopathology and treatment of DDL.

Novel fusion sarcomas including targetable NTRK and ALK

BackgroundChallenging emerging entities with distinctive molecular signatures may benefit from algorithms for diagnostic work-up. MethodsFusion sarcomas (2020–2021, during pandemic) were diagnosed by clinicoradiology, morphology, phenotype, and next-generation sequencing (NGS). ResultsSix fusion sarcomas in two males and four females involved the chest-wall, neck, or extremities; ages ranged 2-73, median 18 years. Sizes ranged 5.3-25.0, median 9.1 cm. These include high grade 1) TPR-NTRK1 of proximal femur with a larger rounded soft tissue mass, previously considered osteosarcoma yet without convincing tumor matrix. A pathologic fracture necessitated emergency hemipelvectomy (NED) and 2) novel KANK1-NTRK2 sarcoma of bone and soft tissue with spindled pleomorphic to epithelioid features (AWD metastases). 3) Novel ERC1-ALK unaligned fusion, a low grade infiltrative deep soft tissue hand sarcoma with prominent-vascularity, myopericytoid/lipofibromatosis-like ovoid cells, and collagenized stroma, was successfully treated with ALK-inhibitor (Crizotinib), avoiding amputation. These NTRK and ALK tumors variably express S100 and CD34 and were negative for SOX10. 4) and 5) CIC-DUX4 round cell tumors (rapid metastases/demise), one with COVID superinfection, were previously treated as Ewing sarcoma. These demonstrated mild pleomorphism and necrosis, variable myxoid change and CD99 reactivity, and a distinctive dot-like-Golgi WT1 immunostaining pattern. 6) A chest wall/thoracic round cell sarcoma, focal CD34/ keratins/CK7, revealed nuclear-STAT6, STAT6-NAB2 by NGS, confirming malignant solitary fibrous tumor, intermediate-risk-stratification (AWD metastases). ConclusionsRecent fusion sarcomas include new KANK1-NTRK2 and ERC1-ALK, the latter successfully treated by targeted-therapy. ALK/NTRK fusion partners TPR and KANK1 suggest unusual high-grade morphology/behavior. Clinicoradiologic, morphologic, and phenotypic algorithms can prompt molecular-targeted immunostains or NGS for final classification and promising inhibitor therapy.

Myopericytoma in the knee joint

Abstract Introduction: Myopericytoma is a relatively new disease entity described by Granter and colleagues in 1998. It is a benign tumor classified as a pericytic/perivascular tumor. Myopericytomas are most commonly seen in the dermis and subcutaneous soft tissue of the peripheral extremities of adults, but some rare reports indicate that myopericytoma can occur in the deep soft tissue around the knee joint. We report a case of a woman in her 30s with myopericytoma around the knee joint. Patient concerns: A 30-year-old woman presented with popliteal pain that increased during deep knee flexion in the left knee. Diagnosis: Magnetic resonance imaging showed a cystic lesion behind the posterior cruciate ligament. An intra-articular lesion was suspected, we performed arthroscopy; however, no lesions were observed. An additional contrast-enhanced magnetic resonance imaging showed a strong contrast effect in the lesion and surrounding soft tissue. We suspected chronic lymphadenitis, hemangiomas, and neoplastic lesions, and an excisional biopsy was performed. Interventions: Through the Burks approach, we performed an excisional biopsy. Based on the characteristic spindle-shaped cell array and immunohistochemistry, the diagnosis was myopericytoma. Outcomes: Six months after surgery, the patient was doing well with no pain. Conclusion: Although myopericytoma is difficult to diagnose preoperatively, it is a disease that should be differentiated from the tumor around the knee joint. The key for diagnosing this disease is histopathological and immunohistochemistry examination.

Anatomic and Radiographic Safe Zone for Posterior Malleolar Screw Placement.

The most appropriate treatment and management of posterior malleolar fractures (PMFs) lacks consensus. Indirect reduction and fixation with posterior to anterior (PA) screw shows promise by avoiding the risks associated with direct reduction or indirect anterior to posterior approaches. Some authors have raised concerns about potential risk to nearby structures with the PA technique, including hardware prominence into the syndesmosis. This study highlights use of the posteromedial vertical syndesmotic line (PVSL) as a fluoroscopic landmark, helping surgeons avoid intrasyndesmotic placement. Study aims are to evaluate PVSL correspondence with posterior border of the incisura tibialis and to define a safe zone between this line and flexor hallucis longus tendon. Indirect PA screw placement was completed on 10 cadaveric specimens, followed by fluoroscopy in mortise and lateral views. Dissection was performed to assess screw placement relative to the posteromedial border of the syndesmosis. The posterior border of the syndesmosis was marked with a radiopaque wire. Repeat imaging was completed to validate the fluoroscopic PVSL is representative of the posteromedial border of the tibial incisura. On dissection, 9 out of 10 cadavers had accurate screw placement with no penetration into the syndesmosis. Corresponding imaging showed the screw head to be medial to the marker on mortise view. For the specimen with penetration into the syndesmosis, imaging confirmed that the screw head was lateral to the marker on mortise views. The radiopaque marker correlated with the PVSL for all specimens when comparing anatomic to radiographic findings. A radiographic safe zone is defined for the PA screw 12 mm medial to the PVSL to ensure no iatrogenic injury to the flexor hallucis longus tendon. This study demonstrated that a posterior incisura tibialis fluoroscopic landmark is unambiguous in localizing the posterior syndesmotic border and that screws medial to this line are safely out of the syndesmosis, while screws placed lateral are either in or at risk of intrasyndesmotic placement. A safe zone is defined for screw placement. This article describes a radiographic and clinical safe zone for fixation and hardware placement during open reduction internal fixation (ORIF) of PMFs. This information will assist surgeons in avoiding intrasyndesmotic hardware placement as well as injury to deep soft tissue structures.

Multifocal cutaneous epithelioid hemangiodothelioma on the same lower limb

&lt;p class="abstract"&gt;Epithelioid hemangioendothelioma (EHE) is a rare low-grade vascular tumour mainly affecting bones, deep soft tissues and exceptionally the skin. Multifocal cutaneous involvement is uncommon and should raise suspicion for metastasizing extracutaneous epithelioid hemangiodothelioma. Hereby we report the case of a young patient with multifocal cutaneous EHE involving the same lower limb. We emphasize the necessity for dermatologists to evoke the diagnosis of EHE in patients presenting with nonspecific tumours of the extremities. Prompt management and diagnosis are essential in this potential aggressive tumour.&lt;/p&gt;

Detection of BCOR gene rearrangement in Ewing-like sarcoma: an important diagnostic tool

BackgroundBCOR-CCNB3 sarcoma (BCS) is a group of undifferentiated small round cell sarcomas harboring the BCOR gene rearrangement which shares morphology with the Ewing sarcoma family as well as other malignant round blue cell tumors, thus making them difficult to diagnose. The aim of this study was to explore the role of molecular techniques in the diagnosis of BCS.MethodsTwenty-three cases of EWSR1 rearrangement-negative undifferentiated small round cell sarcomas (Ewing-like sarcoma) were analyzed for the presence of BCOR gene rearrangement by Fluorescence in situ hybridization (FISH) and Reverse Transcription -Polymerase Chain Reaction (RT-PCR). The clinicopathological features of the positive cases were also reviewed. Fifteen additional cases were used as negative controls.ResultsEight cases were found with BCOR gene rearrangement by FISH and reappraised as BCS. The patients ranged in age from 8 to 20 years old, with a male predominance (M:F = 6:2). All tumors were located in the lower extremities. The tumor locations were more common in bone (n = 6) than deep soft tissue (n = 2). Histologically, 7 of 8 tumors were predominately composed of spindle or ovoid cells. The tumor cells were usually arranged in solid hypercellular sheets without a distinct architectural pattern. IHC showed expression of TLE1 (100%), CCNB3 (88%), BCOR (71%). RT-PCR for BCOR-CCNB3 fusion transcript was positive in 7 of 8 cases. Pre-operative chemotherapy resulted in eradication of tumors in 5 patients after a follow-up of 7 to 42 months.ConclusionsEfficient diagnosis of BCOR rearranged sarcomas is achieved by the using a combination of FISH and RT-PCR assays.

Invasive Group A Streptococcus Infection in Children in Central Israel in 2012-2019.

Group A Streptococcus can cause serious and sometimes life-threatening disease in children. The past few years have witnessed a rise in invasive group A Streptococcus infection (iGASi) for unclear reasons. This study attempted to describe the epidemiology, the clinical and demographic characteristics and the outcomes associated with iGASi in hospitalized children in central Israel. We retrospectively analyzed the medical records of children <18 years old discharged with a diagnosis of iGASi between January 2012 and December 2019. Clinical, laboratory and microbiologic data, and immunization status were retrieved. The patients were divided into severe and nonsevere groups based on their clinical presentation. The emm type was determined at the national reference center. A total of 167 patients with 206 positive cultures for group A Streptococcus were identified. Hospitalizations for iGASi increased from 701 to 958 per 100,000 admissions between 2012-2015 and 2016-2019, respectively, representing an increase of 37%. The majority of the isolates were from the otolaryngologic system followed by blood, deep soft tissue and respiratory sites. Uncomplicated mastoiditis was the most common diagnosis, followed by bacteremia. Pneumonia was the main diagnosis in the severe group (39.4%). The admissions because of iGASi in children <18 years old increased during the last 8 years. Surveillance systems and prospective studies should be conducted to expend our understanding of the epidemiology of iGASi in children, better assess the pathogenesis and specific risk factors and monitor changes in emm-type distribution.

Radiological and histopathological assessment of bone infiltration in soft tissue sarcomas.

Deep soft tissue sarcomas are frequently in contact with bone. The therapeutic decision of a composite resection strategy may be challenging, which is usually based on clinical and radiological criteria. The aims of the study were to evaluate the overall frequency of bone and periosteal infiltration in these patients in whom composite resection was indicated, and evaluate the role of magnetic resonance imaging and bone scintigraphy in this scenario. Forty-nine patients with a composite surgical resection (soft tissue sarcoma and bone), treated at a single institution between 2006 and 2018, were retrospectively included. Presurgical planning of the resection limits was based on clinical and imaging findings (magnetic resonance imaging and bone scintigraphy). Magnetic resonance imaging was performed in all patients (100%) and bone scintigraphy in 41 (83.7% of the cases). According to magnetic resonance imaging results, patients were divided into two groups: Group A, in which the tumor is adjacent to the bone without evidence of infiltration (n = 24, 48,9%), and Group B, patients with evidence of bone involvement by magnetic resonance imaging (n = 25, 51,1%). BS showed a pathological deposit in 28 patients (68.3%). Histological analysis of the resection specimen was preceded to identify bone and periosteal infiltration. For the analysis of the diagnostic validity of imaging tests, histological diagnosis was considered as the gold standard in the evaluation of STS bone infiltration. Histological bone infiltration was identified in 49% of patients and isolated periosteal infiltration in 14.3%. In terms of diagnostic accuracy, magnetic resonance imaging and bone scintigraphy sensitivity values were 92% and 90%, and their specificity values were 91.7% and 52.4%, respectively. The incidence of bone and periosteal infiltration of soft tissue sarcomas in contact with bone is high. Presurgical bone assessment by MRI has proven to be a sensitive and specific tool in the diagnosis of bone infiltration. Due to its high negative predictive value, BS is a useful test to rule out it. In those cases, in which there is suspicion of bone infiltration not confirmed by MRI, new diagnostic protocols should be established in order to avoid inappropriate resections.

Clear cell sarcoma in pelvic region - case report

Clear cell sarcoma is a rare tumor with a predilection to involve tendon and aponeuroses, predominantly around the foot and ankle region. It is clinically, genetically as well as biologically distinct from malignant melanoma, however share some histological and immunohistochemical similarities with it. Clear cell sarcoma usually arise from the deep soft tissue of lower extremities and carries a balanced translocation t(12;22) (q13;q12). The fusion protein activates MiTF, a melanocytic transcription factor which leads to tumor growth and melanin production. The head &amp; neck and trunk are distinctly unusual sites for occurrence of CCS. We herewith describe a CCS in the pelvis of the 26 years-old male patient presented with the chief complaints of paraesthesia, weakness, muscle wasting in right lower limb with foot drop since one year with review of literature.

Low-Grade Fibromyxoid Sarcomas with the Maxillary Sinus Localization: A Case Report and Review of the Literature.

A low-grade fibromyxoid sarcoma (LGFMS) is an extremely rare tumor first described by Evans in 1987. LGFMS is a type of soft tissue sarcoma characterized by a deceptively benign histological appearance but completely malignant behavior. LGFMS is usually seen in the deep soft tissues of the extremities and trunk. We have examined many reviews, case reports and case series previously published in PubMed and Google Scholar. To date, only five cases have been reported in the maxilla. LGFMS generally affects young adults, but it can also be seen in children and older adults. A radical surgical approach is the most recommended treatment option. LGFMS has a very low mitotic activity; therefore, it is considered that neither chemotherapy nor radiotherapy has a significant effect on long-term LGFMS prognosis. However, to date, there has been no study suggesting any protocol for the follow-up of patients with LGFMS. In this report, we present a case with LGFMS located in the maxillary sinus, in which despite radiotherapy following extensive surgical excision, the tumor recurred in a short period of three months and reached its former size.

A Very Rare Case of Necrotizing Fasciitis Caused by Metallosis.

Necrotizing fasciitis is a surgically diagnosed infection of the deep soft tissues that results in high mortality. It is usually caused by aerobic and anaerobic bacteria and group A Streptococcus. Metallosis is characterized by the deposition of metal debris in the blood that causes metal poisoning and tissue damage. The abrasion of metal components that occurs after joint replacements causes metallosis, which may lead to severe complications. We report a rare case of metallosis-induced necrotizing fasciitis of the right thigh. Metallosis should be considered as a cause of necrotizing fasciitis if the patient has had a joint replacement surgery.

Pay attention to the prevention and treatment of iatrogenic wound

The iatrogenic wound is defined as infection, necrosis, or defect of the skin and deep soft tissue resulting from a medical procedure. At present, the main factors causing iatrogenic wounds include surgery, radiotherapy, interventional therapy, and drugs etc. Iatrogenic wounds are attributed to iatrogenic injuries that are in accordance with ethics, laws, and relevant regulations, and the degree of these injuries is within an acceptable range. Medical staff can reduce the incidence of iatrogenic wounds and the degree of injury by improving medical technology and responsibility in medical procedures. Iatrogenic wounds can be repaired and the patient's physical and mental health can be restored with targeted medical treatment. How to effectively prevent and treat iatrogenic wounds so as to minimize the degree of iatrogenic injuries to patients needs further exploration. To sum up, the purpose to publish this special topic in this issue is to arouse the peer's attention to the prevention and treatment of iatrogenic wounds.