Molecular profiling of sarcomas: new vistas for precision medicine

The Recent Advances in Molecular Diagnosis of Soft Tissue Tumors

Soft tissue tumors are rare mesenchymal tumors with divergent differentiation. The diagnosis of soft tissue tumors is challenging for pathologists owing to the diversity of tumor types and histological overlap among the tumor entities. Present-day understanding of the molecular pathogenesis of soft tissue tumors has rapidly increased with the development of molecular genetic techniques (e.g., next-generation sequencing). Additionally, immunohistochemical markers that serve as surrogate markers for recurrent translocations in soft tissue tumors have been developed. This review aims to provide an update on recently described molecular findings and relevant novel immunohistochemical markers in selected soft tissue tumors.

SNHG10/miR-141-3p/WTAP axis promotes osteosarcoma proliferation and migration

LncRNAs have been suggested to participate in the growth and metastasis of cancer through a variety of molecular mechanisms. Recently, SNHG10, a newly discovered lncRNA, is reported to play a role of an oncogene in osteosarcoma (OS) genesis. Nonetheless, the mechanism underlying OS remains unclear. The present work found that SNHG10 expression increased within OS cells and tissues, while suppressing its expression decreased OS cell proliferation, migration, invasion, but increased their apoptosis. As for the mechanism, we confirmed that SNHG10 could bind to miR-141-3p, while the latter could bind to WTAP. SNHG10 upregulated WTAP through decreasing miR-141-3p expression. More importantly, SNHG10 deletion remarkably reduced proliferation, migration, and invasion of cells, but accelerated their apoptosis. However, when cells were subjected to miR-141-3p inhibitor cotransfection or overexpressed WTAP, these effects were partially recovered. In summary, this study suggested that the expression of SNHG10 markedly elevated within OS, and the SNHG10/miR-141-3p/WTAP axis facilitated OS progression.

Immune Checkpoint Inhibitory Therapy in Sarcomas: Is There Light at the End of the Tunnel?

Soft tissue and bone sarcomas are a very heterogeneous group of tumors with many subtypes for which diagnosis and treatment remains a very challenging task. On top of that, the treatment choices are limited, and the prognosis of aggressive sarcomas remains poor. Immune checkpoint inhibitors (ICIs) have drawn a lot of attention last years because of their promising response rates and their durable effects. ICIs are currently widely used in the daily routine practice for the treatment of a different malignancies, such as melanoma, Hodgkin lymphoma, and non-small cell lung carcinoma. Still, ICIs are not included in the standard treatment protocols of the different sarcoma types. However, a plethora of clinical trials investigates the clinical benefit of ICIs in sarcomas. There is clear need to develop predictive biomarkers to determine which sarcoma patients are most likely to benefit from immune checkpoint blockade. This review will focus on (i) the clinical trial results on the use of ICIs in different sarcoma types; and on (ii) possible biomarkers predictive for the effectiveness of these drugs in sarcomas.

Will Next-Generation Immunotherapy Overcome the Intrinsic Diversity and Low Immunogenicity of Sarcomas to Improve Clinical Benefit?

Sarcomas are a rare type of a heterogeneous group of tumours arising from mesenchymal cells that form connective tissues. Surgery is the most common treatment for these tumours, but additional neoadjuvant or adjuvant chemotherapy or radiation therapies may be necessary. Unfortunately, a significant proportion of patients treated with conventional therapies will develop metastatic disease that is resistant to therapies. Currently, there is an urgent need to develop more effective and durable therapies for the treatment of sarcomas. In recent years immunotherapies have revolutionised the treatment of a variety of cancers by restoring patient anti-tumour immune responses or through the adoptive infusion of immune effectors able to kill and eliminate malignant cells. The clinicopathologic and genetic heterogeneity of sarcomas, together with the generally low burden of somatic mutations potentially generating neoantigens, are currently limited to broad application of immunotherapy for patients with sarcomas. Nevertheless, a better understanding of the microenvironmental factors hampering the efficacy of immunotherapy and the identification of new and suitable therapeutic targets may help to overcome current limitations. Moreover, the recent advances in the development of immunotherapies based on the direct exploitation or targeting of T cells and/or NK cells may offer new opportunities to improve the treatment of sarcomas, particularly those showing recurrence or resistance to standard of care treatments.

Secondary cytoreductive surgery in recurrent uterine leiomyosarcoma: a multi-institutional study

INTRODUCTION

Uterine leiomyosarcoma (uLMS) represents a rare gynecological malignancy with high incidence of recurrence. Evidence in literature about the management of recurrent uLMS is limited, and the role of secondary cytoreduction has been evaluated in small and heterogeneous populations. The objective of this study is to assess the prognostic role of secondary cytoreductive surgery and its related complications in a large and homogeneous group of patients.

METHODS

All consecutive patients who underwent surgery for recurrent uLMS between 01/2010-01/2018 at four Italian tertiary referral centers, were included. Relevant demographic and clinico-pathologic data were retrieved. Survival curves were estimated by Kaplan-Meier method and compared by log-rank test. Cox-proportional hazard model was used to assess the effect of the most predictive prognostic variables.

RESULTS

38 patients with recurrent uLMS were treated with secondary cytoreductive surgery in the study period. Recurrence presented as isolated disease in 17 (44.7%) cases. Bowel, bladder and upper abdominal surgery was performed in 50.0%, 18.4% and 28.9% of the cases, respectively. No residual tumor was the final surgical result in 35 (92.1%) patients. Median hospital stay was 7 days (range, 1-24). No women had major intra-operative and 4 (33.3%) had major post-operative complications. No patient died within 30-days from the secondary cytoreduction. Median time to the first cycle of adjuvant chemotherapy was 41-days (range, 29-78). Median recurrence-free survival was 16.0months (95%CI,11.6 to 26.1). 5-year overall survival (OS) was 76% (95%CI,53 to 89%). Time to first recurrence >12months significantly affected OS (p=0.04).

DISCUSSION

Secondary cytoreduction in recurrent uLMS often requires complex and extensive surgical procedures. Referral to tertiary centers guarantees low peri-operative morbidity, short length of hospitalization and median time to chemotherapy within the standard of care. Therefore, secondary cytoreduction to no residual disease is an option that may be considered in recurrent uLMS, especially in patients with time to first recurrence >12months.