Management of Myxofibrosarcoma and Undifferentiated Pleomorphic Sarcoma

An aggressive soft-tissue sarcoma of the extremity: A myxofibrosarcoma, grade 3 (FNCLCC system)

We report a case of myxofibrosarcoma of the posterior region of the femur, part of the group of soft-tissue sarcomas: a set of rare and heterogeneous tumors with various subtypes and different prognostic. It is characterized by local infiltrative activity and an extremely high rate of local recurrence. A 58-year-old man came to the Radiology Department to examine a voluminous round and expansive formation of the posterior thigh region. The patient stated that the mass had grown suddenly for about 3 months, maybe after a trauma, increasing in volume exponentially and causing him discomfort, embarrassment, and pain. The result of the first diagnostic approach, with the US, was unexpected and suspicious, and the radiologist wanted to do first a CT, and then maybe plan an MRI. The CT revealed an inhomogeneous density formation and in MRI the mass resulted to be compatible, with the radiologic pattern, with the diagnosis of a sarcoma of the soft tissue. The physicians had already alerted the pathological anatomy, as they suspected something malignant. So, some days after the MRI examination, the patient underwent histological sampling, confirming the suspicion: a myxofibrosarcoma (stage III) of the posterior region of the femoral region. The patient started on radio and chemotherapy, which increases survival and in the hope of reducing the size of the mass, and a strict follow-up was posed before doing the surgery.

From oncogenes to tumor suppressors: The dual role of ncRNAs in fibrosarcoma

Fibrosarcoma is a challenging cancer originating from fibrous tissues, marked by aggressive growth and limited treatment options. The discovery of non-coding RNAs (ncRNAs), including long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and small interfering RNAs (siRNAs), has opened new pathways for understanding and treating this malignancy. These ncRNAs play crucial roles in gene regulation, cellular processes, and the tumor microenvironment. This review aims to explore the impact of ncRNAs on fibrosarcoma's pathogenesis, progression, and resistance to treatment, focusing on their mechanistic roles and therapeutic potential. A comprehensive review of literature from databases like PubMed and Google Scholar was conducted, focusing on the dysregulation of ncRNAs in fibrosarcoma, their contribution to tumor growth, metastasis, drug resistance, and their cellular pathway interactions. NcRNAs significantly influence fibrosarcoma, affecting cell proliferation, apoptosis, invasion, and angiogenesis. Their function as oncogenes or tumor suppressors makes them promising biomarkers and therapeutic targets. Understanding their interaction with the tumor microenvironment is essential for developing more effective treatments for fibrosarcoma. Targeting ncRNAs emerges as a promising strategy for fibrosarcoma therapy, offering hope to overcome the shortcomings of existing treatments. Further investigation is needed to clarify specific ncRNAs' roles in fibrosarcoma and to develop ncRNA-based therapies, highlighting the significance of ncRNAs in improving patient outcomes in this challenging cancer.

Modeling Myxofibrosarcoma: Where Do We Stand and What Is Missing?

Myxofibrosarcoma (MFS) is a malignant soft tissue sarcoma (STS) that originates in the body's connective tissues. It is characterized by the presence of myxoid (gel-like) and fibrous components and typically affects patients after the fifth decade of life. Considering the ongoing trend of increasing lifespans across many nations, MFS is likely to become the most common musculoskeletal sarcoma in the future. Although MFS patients have a lower risk of developing distant metastases compared with other STS cases, MFS is characterized by a high frequency of local recurrence. Notably, in 40-60% of the patients where the tumor recurs, it does so multiple times. Consequently, patients may undergo multiple local surgeries, removing the risk of potential amputation. Furthermore, because the tumor relapses generally have a higher grade, they exhibit a decreased response to radio and chemotherapy and an increased tendency to form metastases. Thus, a better understanding of MFS is required, and improved therapeutic options must be developed. Historically, preclinical models for other types of tumors have been instrumental in obtaining a better understanding of tumor development and in testing new therapeutic approaches. However, few MFS models are currently available. In this review, we will describe the MFS models available and will provide insights into the advantages and constraints of each model.

Retroperitoneal undifferentiated pleomorphic sarcoma with total nephrectomy: a case report and literature review

Background

Undifferentiated pleomorphic sarcoma (UPS) is a highly malignant soft tissue sarcoma with a poor prognosis and no clear effective clinical means for treatment, and there has been no significant progress in research within this field in recent years. This study aimed to investigate the epidemiology, etiology, clinical features, diagnostic modalities, various treatment modalities, and prognosis of retroperitoneal undifferentiated pleomorphic sarcoma and to contribute to the clinical management of this type of disease. In this study, we report a case of undifferentiated pleomorphic sarcoma with a primary origin in the retroperitoneum. Undifferentiated pleomorphic sarcoma occurring in the retroperitoneum is rarely reported.

Case description

A 59-year-old man with abdominal distension and pain for 4 months presented to our hospital after the failure of conservative treatment. A 9.6 cm by 7.4 cm mass in the left retroperitoneum was found on a CT scan of the whole abdomen with three degrees of enhancement. After surgical treatment, the tumor and the left kidney were completely removed, and pathological examination and genetic sequencing showed an apparent undifferentiated pleomorphic sarcoma. The patient subsequently declined follow-up treatment and is currently alive and well.

Conclusions

At the current level of clinical technology, the treatment of undifferentiated pleomorphic sarcoma is still in the exploratory stage, and the scarcity of clinical cases of this disease may have hindered the acquisition of clinical trials and research data for this disease. At present, the first choice of treatment for undifferentiated pleomorphic sarcoma is still radical resection. In the existing clinical studies, there are no strong data to support the effect of preoperative neoadjuvant chemoradiotherapy and adjuvant chemoradiotherapy in clinical practice. Similar to other diseases, the use of radiotherapy and chemotherapy before and after surgery may be a potential treatment for this disease in the future. Targeted therapy for this disease still needs further exploration, and we need more reports on related diseases to promote future treatment and research on this disease.

High-grade pleomorphic sarcoma associated with an orthopedic implant: a rare case report

The use of prosthetic implants and metallic materials is widespread in modern orthopedic surgery. Generally, these materials are non-toxic and inert. Nevertheless, a few cases of malignancy associated with certain implants have been documented in the literature. It has been reported that some components of these implants have carcinogenic properties. In most cases, these tumors are high-grade sarcomas that occur in the bone or soft tissue adjacent to the implant site. Here we present the case of a 53-year-old patient who underwent intramedullary nailing of the tibia and developed a pleomorphic sarcoma at the implant site 18 years later.

Wide Resection Preserving Conjoined Tendons of the Rotator Cuff Muscles for Undifferentiated Pleomorphic Sarcoma at the Suprascapular Fossa - A Case Report

Surgical principles in sarcoma are a wide resection, including surrounding tissues and maximisation of the function of the affected limb. Rotator cuff muscles are biomechanically important structures acting as a force couple in movement of the shoulder joint. Thus, conjoined tendons are essential for motion capability in absence of the supraspinatus muscle. This article reports a case of a large undifferentiated pleomorphic sarcoma (UPS) at the suprascapular fossa in a 78-year-old man. After diagnosis of sarcoma, he underwent wide, en-bloc excision preserving conjoined tendons of rotator cuff muscles and low-dose radiation therapy for surveillance of local recurrence. All dissection was performed to avoid contaminating the tumour and involved the whole supraspinatus except the conjoined tendons. We report a case of UPS at the suprascapular fossa, which showed a good result after a wide resection preserving conjoined tendons of rotator cuff muscles. Level of Evidence: Level V (Therapeutic).

Unveiling the Genomic Basis of Chemosensitivity in Sarcomas of the Extremities: An Integrated Approach for an Unmet Clinical Need

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) can be considered as a spectrum of the same disease entity, representing one of the most common adult soft tissue sarcoma (STS) of the extremities. While MFS is rarely metastasizing, it shows an extremely high rate of multiple frequent local recurrences (50-60% of cases). On the other hand, UPS is an aggressive sarcoma prone to distant recurrence, which is correlated to a poor prognosis. Differential diagnosis is challenging due to their heterogeneous morphology, with UPS remaining a diagnosis of exclusion for sarcomas with unknown differentiation lineage. Moreover, both lesions suffer from the unavailability of diagnostic and prognostic biomarkers. In this context, a genomic approach combined with pharmacological profiling could allow the identification of new predictive biomarkers that may be exploited for differential diagnosis, prognosis and targeted therapy, with the aim to improve the management of STS patients. RNA-Seq analysis identified the up-regulation of MMP13 and WNT7B in UPS and the up-regulation of AKR1C2, AKR1C3, BMP7, and SGCG in MFS, which were confirmed by in silico analyses. Moreover, we identified the down-regulation of immunoglobulin genes in patient-derived primary cultures that responded to anthracycline treatment compared to non-responder cultures. Globally, the obtained data corroborated the clinical observation of UPS as an histotype refractory to chemotherapy and the key role of the immune system in determining chemosensitivity of these lesions. Moreover, our results confirmed the validity of genomic approaches for the identification of predictive biomarkers in poorly characterized neoplasms as well as the robustness of our patient-derived primary culture models in recapitulating the chemosensitivity features of STS. Taken as a whole, this body of evidence may pave the way toward an improvement of the prognosis of these rare diseases through a treatment modulation driven by a biomarker-based patient stratification.

A League of Its Own? Established and Emerging Therapies in Undifferentiated Pleomorphic Sarcoma

OPINION STATEMENT

Over the last decade in soft tissue sarcoma (STS) research, the shifting landscape towards more precise subtype classification and the increasing study of novel therapeutic strategies has prompted a need to highlight current knowledge of effective subtype specific therapies. Undifferentiated pleomorphic sarcoma (UPS), formerly known as malignant fibrous histiocytoma (MFH), is among the most common subtypes of STS arising in the trunk or extremities of adults. Administration of systemic chemotherapy is the primary management in locally advanced and metastatic UPS. While anthracycline-based chemotherapy continues to be standard of care in this setting, outcomes in locally advanced or metastatic UPS remain poor. Recent studies highlight the unique characteristics of UPS that may contribute to its greater sensitivity to immune checkpoint inhibition (ICI) compared to other STS subtypes. With the promise of benefit from novel therapies, including ICI or ICI plus chemotherapy, for a subset of patients with UPS comes the need to identify biomarkers predictive of response to therapy. Ongoing and future clinical trials should place strong emphasis on correlative biomarker studies to learn more about the unique biology of UPS and to identify patients for whom ICI-based therapy will be effective.

The immune subtypes and landscape of sarcomas

Background

Considering the molecular heterogeneity of sarcomas and their immunologically quiet character, immunotherapy (e.g., immune checkpoint inhibitors) plays a viable role in only a subset of these tumors. This study aimed to determine the immune subtypes (IMSs) of sarcomas for selecting suitable patients from an extremely heterogeneous population.

Results

By performing consensus clustering analysis of the gene expression profiles of 538 patients with sarcomas in online databases, we stratified sarcomas into three IMSs characterized by different immune cell features, tumor mutational burdens (TMBs), gene mutations, and clinical outcomes. IMS1 showed an immune “hot” and immunosuppressive phenotype, the highest frequencies of CSMD3 mutation but the lowest frequencies of HMCN1 and LAMA2 mutations; these patients had the worst progression-free survival (PFS). IMS2 was defined by a high TMB and more gene mutations, but had the lowest frequency of MND1 mutations. IMS3 displayed the highest MDN1 expression level and an immune “cold” phenotype, these patients had the worst PFS. Each subtype was associated with different expression levels of immunogenic cell death modulators and immune checkpoints. Moreover, we applied graph learning-based dimensionality reduction to the immune landscape and identified significant intra-cluster heterogeneity within each IMS. Finally, we developed and validated an immune gene signature with good prognostic performance.

Conclusions

Our results provide a conceptual framework for understanding the immunological heterogeneity of sarcomas. The identification of immune-related subtypes may facilitate optimal selection of sarcoma patients who will respond to appropriate therapeutic strategies.