Soft tissue sarcomas in children

A Case Study of a Rare Undifferentiated Spindle Cell Sarcoma of the Penis: Establishment and Characterization of Patient-Derived Models

Rare sarcomas present significant treatment challenges compared to more prevalent soft tissue sarcomas due to limited treatment options and a poor understanding of their biology. This study investigates a unique case of penile sarcoma, providing a comprehensive morphological and molecular analysis. Through the creation of experimental patient-derived models-including patient-derived xenograft (PDX), 3D, and monolayer primary cultures-we successfully replicated crucial molecular traits observed in the patient's tumor, such as smooth muscle actin and CD99 expression, along with specific mutations in genes like TSC2 and FGFR4. These models are helpful in assessing the potential for an in-depth exploration of this tumor's biology. This comprehensive approach holds promise in identifying potential therapeutic avenues for managing this exceedingly rare soft tissue sarcoma.

Evaluation of the Synthetic Multifunctional Peptide Hp-MAP3 Derivative of Temporin-PTa

In recent years, antimicrobial peptides isolated from amphibian toxins have gained attention as new multifunctional drugs interacting with different molecular targets. We aimed to rationally design a new peptide from temporin-PTa. Hp-MAP3 (NH2-LLKKVLALLKKVL-COOH), net charge (+4), hydrophobicity (0.69), the content of hydrophobic residues (69%), and hydrophobic moment (0.73). For the construction of the analog peptide, the physicochemical characteristics were reorganized into hydrophilic and hydrophobic residues with the addition of lysines and leucines. The minimum inhibitory concentration was 2.7 to 43 μM against the growth of Gram-negative and positive bacteria, and the potential for biofilm eradication was 173.2 μM. Within 20 min, the peptide Hp-MAP3 (10.8 μM) prompted 100% of the damage to E. coli cells. At 43.3 μM, eliminated 100% of S. aureus within 5 min. The effects against yeast species of the Candida genus ranged from 5.4 to 86.6 μM. Hp-MAP3 presents cytotoxic activity against tumor HeLa at a concentration of 21.6 μM with an IC50 of 10.4 µM. Furthermore, the peptide showed hemolytic activity against murine erythrocytes. Structural studies carried out by circular dichroism showed that Hp-MAP3, while in the presence of 50% trifluoroethanol or SDS, an α-helix secondary structure. Finally, Amphipathic Hp-MAP3 building an important model for the design of new multifunctional molecules.

Comprehensive analysis of a novel cuproptosis-related lncRNA signature associated with prognosis and tumor matrix features to predict immunotherapy in soft tissue carcinoma

Background: A crucial part of the malignant processes of soft tissue sarcoma (STS) is played by cuproptosis and lncRNAs. However, the connection between cuproptosis-related lncRNAs (CRLs) and STS is nevertheless unclear. As a result, our objective was to look into the immunological activity, clinical significance, and predictive accuracy of CRLs in STS. Methods: The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases, respectively, provided information on the expression patterns of STS patients and the general population. Cuproptosis-related lncRNA signature (CRLncSig) construction involved the univariate, multivariate, and least absolute shrinkage and selection operator Cox regression analysis. The predictive performance of the CRLncSig was evaluated using a serial analysis. Further research was done on the connections between the CRLncSig and the tumor immune milieu, somatic mutation, immunotherapy response, and chemotherapeutic drug susceptibility. Notably, an in vitro investigation served to finally validate the expression of the hallmark CRLs. Results: A novel efficient CRLncSig composed of seven CRLs was successfully constructed. Additionally, the low-CRLncSig group's prognosis was better than that of the high-CRLncSig group's based on the new CRLncSig. The innovative CRLncSig then demonstrated outstanding, consistent, and independent prognostic and predictive usefulness for patients with STS, according to the evaluation and validation data. The low-CRLncSig group's patients also displayed improved immunoreactivity phenotype, increased immune infiltration abundance and checkpoint expression, and superior immunotherapy response, whereas those in the high-CRLncSig group with worse immune status, increased tumor stemness, and higher collagen levels in the extracellular matrix. Additionally, there is a noticeable disparity in the sensitivity of widely used anti-cancer drugs amongst various populations. What's more, the nomogram constructed based on CRLncSig and clinical characteristics of patients also showed good predictive ability. Importantly, Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR) demonstrated that the signature CRLs exhibited a significantly differential expression level in STS cell lines. Conclusion: In summary, this study revealed the novel CRLncSig could be used as a promising predictor for prognosis prediction, immune activity, tumor immune microenvironment, immune response, and chemotherapeutic drug susceptibility in patients with STS. This may provide an important direction for the clinical decision-making and personalized therapy of STS.

A review of paediatric soft tissues masses referred to a tertiary musculoskeletal sarcoma centre

OBJECTIVES

To determine the differential diagnosis of musculoskeletal soft tissue masses in children referred to a specialist musculoskeletal oncology unit.

METHODS

All children (0-18 y) referred to a specialist musculoskeletal oncology unit over a 20-month period (September 2018-May 2020) were retrospectively reviewed. Demographic data and referral diagnoses were obtained from the electronic patient notes. MRI findings and histopathological results were recorded. The comparison of non-neoplastic, benign neoplastic and malignant diagnoses at the point of referral and final diagnosis was determined.

RESULTS

116 patients were included, 60 (51.7%) males and 56 (48.3%) females with mean age of 10.6 years (3 months-18 years). 69 (59.5%) patients were referred with a suspected sarcoma, 29 (25.0%) with a suspected benign tumour and 18 (15.5%) with a non-neoplastic lesion. A diagnosis was achieved by histological assessment in 61 (52.6%) cases, microbiological assessment in 3 (2.6%) or clinical and imaging assessment in 52 (44.8%). 67 (57.8%) cases had non-neoplastic pathology, 39 (33.6%) a benign tumour, 4 (3.4%) an intermediate-grade tumour, 6 (5.2%) a malignant tumour.

CONCLUSIONS

Although over half of children referred to a specialist musculoskeletal oncology unit were suspected of having a soft tissue sarcoma at referral, only 5.2% were diagnosed with a malignant tumour.

ADVANCES IN KNOWLEDGE

Approximately, 6 of 69 (8.7%) children referred to a specialist musculoskeletal oncology unit with a suspected soft tissue sarcoma will have a malignant lesion. Most paediatric soft tissue masses are non-neoplastic, the commonest diagnosis being a vascular malformation.

Pediatric Soft Tissue and Bone Sarcomas in Tanzania: Epidemiology and Clinical Features

PURPOSE

Pediatric sarcomas represent an important group of childhood tumors that require treatment at Muhimbili National Hospital (MNH), the largest pediatric oncology center in Tanzania. Treatment is often adapted from established childhood protocols validated in clinical trials from the United States and the United Kingdom. There are no studies describing the types of pediatric sarcomas most commonly seen in Tanzania to understand similarities and disparities with other countries and which sarcomas to prioritize in adapting treatment protocols. The objective of this study was to establish a baseline of the epidemiologic and clinical features of pediatric sarcomas diagnosed at MNH.

METHODS

Information was collected on clinical and tumor features of all children seen at MNH pediatric oncology unit between 2011 and 2016 with a confirmed histologic diagnosis of either bone or soft tissue sarcoma (STS).

RESULTS

A total of 135 cases were analyzed; 89 (66%) were STS and 46 (34%) were bone sarcomas. There was a slight female predominance (n = 69; 51%), and the mean age (SD) of patients was 6.3 (5.1) years. Greater than 90% (n = 123) of the cases presented with a painless swelling. The commonest STS, accounting for almost three-fourths of the cases (n = 66) was rhabdomyosarcoma (RMS), with embryonal subtype being the most common RMS (n = 49; 74%). Osteosarcoma was the most common bone sarcoma, accounting for greater than 80% (n = 40) of the cases. Ewing sarcoma accounted for less than 15% (n = 6). Most of the patients presented with stage IV disease (n = 57; 87%) and lung was the commonest metastatic site.

CONCLUSION

To our knowledge, this report is the first study documenting the epidemiologic and clinical features of pediatric sarcomas in a modern Tanzanian pediatric hospital. Embryonal RMS and osteosarcomas should be prioritized for adapting treatment protocols from other countries.

Pediatric soft tissue sarcoma of the limbs: clinical outcome of 97 patients

PURPOSE

Soft tissue sarcomas (STS) of the extremities in children are a heterogeneous group of tumors with a very different prognosis for which optimal treatment remains controversial.

PATIENTS AND METHODS

We retrospectively evaluated 97 patients younger than 15 years old affected by limb soft tissue sarcomas. All cases were histologically revised, and tumor grade was assessed according to the FNLCC system. Thirty-two were rhabdomyosarcoma (RMS) and 65 non-rhabdomyosarcoma (NRMSTS); among these, 40 (61.5%) were grade 3 according to FNLCC classification. Overall survival, local recurrence and distant metastasis were analyzed.

RESULTS

Overall survival was 77.8% at 5 years and 69.7% at 10 years. Among grade 3 tumors, RMS had a worse prognosis over NRSTS. Similarly, tumors larger than 5 cm had a worse prognosis compared to smaller ones. Local recurrence-free survival was 90.7% at 5 years and 87.1% at 10 years with a better local control in grade 3 NRSTS over RMS and in tumors smaller than 2 cm.

CONCLUSION

Children affected by extremities RMS were confirmed to have the worst prognosis, in particular in case of metastasis at presentation. Differently from adult patients, hand and feet locations are frequent site for STS and 2 cm diameter should be taken as cut off for higher risk of LR. Similarly to adulthood STS, grading correlates with prognosis in NRSTS. The identification of prognostic variables should enable risk-adapted therapies to be planned.

Low-grade Nonrhabdomyosarcoma Soft Tissue Sarcoma: What is Peculiar for Childhood

BACKGROUND

Nearly half of soft tissue sarcomas are nonrhabdomyosarcomas (NRSTSs). The low-grade (LG) form comprises a heterogenous group of diseases that rarely metastasize but are known for local recurrence.

AIM OF THE STUDY

The aim of the study was to retrospectively evaluate pediatric LG-NRSTS with regard to demography, survival, and factors affecting outcome in Egyptian patients.

PATIENTS AND METHODS

The study reviewed 66 NRSTS patients who presented to the Pediatric Oncology Department, National Cancer Institute, Cairo University, between January 2008 and December 2013.

RESULTS

Out of the reviewed cases 32 patients had LG tumors and were eligible for analysis. The male to female ratio was 1:1 and the median age was 7.5 years (range, 1 mo to 18 y). Desmoid fibromatosis (N=18) showed frequent local recurrence and nearly half of this group was alive without disease. No recurrence of the disease occurred in the nonfibromatosis group (n=14) and all patients were alive and free of disease. The 5-year overall survival was 88% for the entire group of study patients versus 45% for event-free survival. Tumors >5 cm in diameter and fibromatosis histology subtype were associated with lower EFS.

CONCLUSIONS

LG-NRSTS generally has good prognosis, with overall survival reaching 90%. However, aggressive fibromatosis usually runs a poorer course in the form of high incidence of local recurrence and lower survival rates. This needs to be further assessed in larger prospective studies including novel therapies in addition to the current conventional modalities.

Current management of pediatric soft tissue sarcomas

Pediatric soft tissue sarcomas are a group of malignant neoplasms arising within embryonic mesenchymal tissues during the process of differentiation into muscle, fascia and fat. The tumors have a biphasic peak for age of incidence. Rhabdomyosarcoma (RMS) is diagnosed more frequently in younger children, whereas adult-type non-RMS soft tissue sarcoma is predominately observed in adolescents. The latter group comprises a variety of rare tumors for which diagnosis can be difficult and typically requires special studies, including immunohistochemistry and molecular genetic analysis. Current management for the majority of pediatric sarcomas is based on the data from large multi-institutional trials, which has led to great improvements in outcomes over recent decades. Although surgery remains the mainstay of treatment, the curative aim cannot be achieved without adjuvant treatment. Pre-treatment staging and risk classification are of prime importance in selecting an effective treatment protocol. Tumor resectability, the response to induction chemotherapy, and radiation generally determine the risk-group, and these factors are functions of tumor site, size and biology. Surgery provides the best choice of local control of small resectable tumors in a favorable site. Radiation therapy is added when surgery leaves residual disease or there is evidence of regional spread. Chemotherapy aims to reduce the risk of relapse and improve overall survival. In addition, upfront chemotherapy reduces the aggressiveness of the required surgery and helps preserve organ function in a number of cases. Long-term survival in low-risk sarcomas is feasible, and the intensity of treatment can be reduced. In high-risk sarcoma, current research is allowing more effective disease control.