Phase II study of sunitinib malate, a multitargeted tyrosine kinase inhibitor in patients with relapsed or refractory soft tissue sarcomas. Focus on three prevalent histologies: leiomyosarcoma, liposarcoma and malignant fibrous histiocytoma

Molecular characteristics and systemic treatment options of liposarcoma: A systematic review

Liposarcoma (LPS) is a rare soft tissue sarcoma that develops from the differentiation of fat cells, typically occurring in the lower extremities and retroperitoneal space. Depending on its histological morphology and molecular changes, LPS can be divided into various subtypes, each exhibiting distinct biological behaviors. During treatment, especially for LPS arising in the retroperitoneum, the extent and quality of the initial surgery are critically important. Treatment strategies must be tailored to the specific type of LPS. Over the past few decades, the treatment of LPS has undergone numerous advancements, with new therapeutic approaches such as targeted drugs and immunotherapies continually emerging. This paper reviews the biological characteristics, molecular alterations, as well as surgical and pharmacological treatments of various LPS subtypes, with the aim of enhancing clinicians' understanding and emphasizing the importance of individualized precision therapy. With a deeper understanding of the biological characteristics and molecular alterations of LPS, future treatment trends are likely to focus more on developing personalized treatment plans to better address the various types of LPS.

Genetic, Epigenetic and Transcriptome Alterations in Liposarcoma for Target Therapy Selection

Liposarcoma (LPS) is one of the most common adult soft-tissue sarcomas (STS), characterized by a high diversity of histopathological features as well as to a lesser extent by a spectrum of molecular abnormalities. Current targeted therapies for STS do not include a wide range of drugs and surgical resection is the mainstay of treatment for localized disease in all subtypes, while many LPS patients initially present with or ultimately progress to advanced disease that is either unresectable, metastatic or both. The understanding of the molecular characteristics of liposarcoma subtypes is becoming an important option for the detection of new potential targets and development novel, biology-driven therapies for this disease. Innovative therapies have been introduced and they are currently part of preclinical and clinical studies. In this review, we provide an analysis of the molecular genetics of liposarcoma followed by a discussion of the specific epigenetic changes in these malignancies. Then, we summarize the peculiarities of the key signaling cascades involved in the pathogenesis of the disease and possible novel therapeutic approaches based on a better understanding of subtype-specific disease biology. Although heterogeneity in liposarcoma genetics and phenotype as well as the associated development of resistance to therapy make difficult the introduction of novel therapeutic targets into the clinic, recently a number of targeted therapy drugs were proposed for LPS treatment. The most promising results were shown for CDK4/6 and MDM2 inhibitors as well as for the multi-kinase inhibitors anlotinib and sunitinib.

Pharmacokinetics and bioequivalence of sunitinib and Sutent® in Chinese healthy subjects: an open-label, randomized, crossover study

Purpose: The purpose of this study was to examine the pharmacokinetics (PK), bioequivalence and safety of generic sunitinib and its original product Sutent® in healthy Chinese subjects through a phase-I clinical trial. Methods: The study selected two groups of 24 healthy Chinese subjects in a 1:1 ratio through random allocation. Each participant received either 12.5 mg of sunitinib or Sutent® per cycle. A total of 15 different time points were employed for blood sample collection during each cycle. Furthermore, a comprehensive assessment of the drugs' safety was consistently maintained throughout the trial. Results: The average adjusted geometric mean ratios (GMR) (90% CI) for the primary PK parameters Cmax, AUC0-t and AUC0-∞ were 97.04% (93.06%-101.19%), 98.45% (93.27%-103.91%) and 98.22% (93.15%-103.56%), respectively. The adjusted GMRs for essential pharmacokinetic (PK) parameters all met the requirements for bioequivalence, with values within the acceptable range of 80%-125%. In addition, the two drugs showed comparable results for the other PK parameters. These results indicate that the two drugs were bioequivalent. Furthermore, both drugs showed well safety. Conclusion: The research results proved that the PK and safety profiles of sunitinib in healthy Chinese subjects were comparable to those of Sutent®. These results advocate the clinical application of generic sunitinib as a potential alternative to original product Sutent® in the treatment of certain medical conditions.

Biology and Management of High-Grade Myxofibrosarcoma: State of the Art and Future Perspectives

Myxofibrosarcoma (MFS) is one of the most common adult soft tissue sarcomas, typically arising in the extremities. Histologically, MFS is classified into three grades: low, intermediate, and high. Histological grades correlate with distant metastases and tumor-associated mortality. The diagnosis of MFS is challenging due to a lack of well-characterized immunohistochemical markers. High-grade MFS displays highly complex karyotypes with multiple copy number alterations. Recent integrated genomic studies have shown the predominance of somatic copy number aberrations. However, the molecular pathogenesis of high-grade MFS remains poorly understood. The standard treatment for localized MFS is surgical resection. The systemic treatment options for advanced disease are limited. This review provides an updated overview of the clinical and imaging features, pathogenesis, histopathology, and treatment of high-grade MFS.

Renal Leiomyosarcoma: Unraveling the Mysteries of a Rare Malignancy

Primary leiomyosarcoma is a rare malignant kidney tumor. The diagnosis of this disease is usually made on the basis of histological examination because it lacks specific clinical or radiological characteristics. Differentiation between leiomyosarcoma and sarcomatoid renal cell carcinoma can be challenging because spindle cell morphology is observed in both tumors. Therefore, caution should be exercised when making a diagnosis of primary renal leiomyosarcoma. Both renal sarcoma and sarcomatoid renal cell carcinoma have a worse prognosis, and nephrectomy is the treatment of choice in locally resectable tumors. An example of such a tumor is discussed in relation to its diagnostic challenges. We report a case of a 35-year-old female who presented with a left renal mass. A left radical nephrectomy was performed, and a firm, tan-white, lobulated tumor (14x8x7.5 cm) was present on gross examination. A histological diagnosis of high-grade leiomyosarcoma was made on the basis of histology, positivity for caldesmon and desmin, and negative cytokeratin immunostaining. Sarcomatoid renal cell carcinoma was ruled out based on morphological findings after extensive sampling of the tumor along with negativity for CK, CD-10, and carbonic anhydrase IX immunostaining.

Regorafenib for the Treatment of Sarcoma

OPINION STATEMENT

Sarcomas are a rare group of tumors with many subtypes, conventionally classified into soft-tissue sarcomas and bone sarcomas. Chemotherapeutic regimens form the mainstay of systemic therapy but are not well defined beyond the first-line setting and clinical outcomes are variable. Tyrosine kinase inhibitors (TKIs), with a broad inhibition profile which have been shown to target tumor angiogenesis, have an established role in the treatment of sarcomas without characteristic driver alterations. One such TKI, regorafenib, has been evaluated in sarcomas and clinical data are discussed in this review. An overview of regorafenib data from five phase 2 and one phase 1b clinical trials in over 10 sarcoma subtypes (both soft-tissue and bone) in adult and pediatric patients is reviewed. Regorafenib demonstrated clinical benefit in patients with non-adipocytic soft-tissue sarcomas, osteosarcoma and Ewing sarcoma who had progressed on prior therapy. Patients with otherwise limited treatment options may therefore benefit from regorafenib therapy.

Tsp2 Facilitates Tumor-associated Fibroblasts Formation and Promotes Tumor Progression in Retroperitoneal Liposarcoma

Retroperitoneal liposarcoma (RLPS) is the most common subtype of retroperitoneal soft tissue sarcoma, characterized by a high recurrence rate and insensitivity to radiotherapy and chemotherapy. The function of tumor microenvironmental components, especially tumor-associated fibroblasts (TAFs), remains unclear in RLPS. The crosstalk between tumor cells and stromal cells should be clarified for therapy target discovery in RLPS. In this study, we demonstrated that TAFs from dedifferentiated liposarcoma (DDLPS) could attract LPS cells and promote their proliferation and migration. However, although α-SMA is positively expressed in RLPS, its expression does not indicate prognosis. By screening differentially expressed genes, performing Oncomine visualization, TCGA gene expression correlation analysis and qPCR verification, we determined that thrombospondin-2 (THBS2) gene expression was related to TAFs. The expression of Tsp2 protein, which was encoded by THBS2, was correlated with α-SMA expression, and it was an independent predictive factor for disease-free survival and recurrence-free survival in patients with RLPS. In vitro, Tsp2 facilitated the transformation of bone marrow-derived fibroblasts (BMFs) to TAFs and promoted the malignant biological behaviors of LPS cells by activating the MAPK/MEK/ERK pathway. Therefore, suppression of Tsp2 is expected to be a promising treatment method for RLPS patients.

Surgical management of primary undifferentiated pleomorphic sarcoma of the rectum: a case report and review of the literature

Background

Undifferentiated pleomorphic sarcoma (UPS) is a malignant soft tissue tumor that has been reclassified from malignant fibrous histiocytoma with the development of the pathological diagnosis. It principally occurs in the extremities but rarely occurs in the rectum. We herein report a rare case of UPS arising in the rectum.

Case presentation

A 85-year-old woman was referred to our hospital with a complaint of anal pain, which had persisted for several months. Computed tomography (CT) showed a 53 × 58 × 75 mm mass on the left side of the rectum. Colonoscopy revealed a submucosal elevation in the rectum without any exposure of the tumor to the surface. Contrast-enhanced CT and magnetic resonance imaging revealed an 80-mm mass that originated in the rectal muscular propria, and we suspected a gastrointestinal stromal tumor. No lymph node metastasis or distant metastasis was observed. We performed a laparoscopic Hartmann’s operation. Intraoperatively, severe adhesion around the tumor caused tumor injury and right ureteral dissection. Thus, laparoscopic right ureteral anastomosis and ureteral stenting were additionally performed. The operation time was 6 h and 3 min, and the estimated blood loss was small. The patient was discharged without complications 25 days after surgery. A pathological examination showed that the tumor was composed of highly heterogeneous cells with no specific differentiation traits, leading to a diagnosis of UPS. Contrast-enhanced CT performed 2 months after surgery showed bilateral pelvic lymph node enlargement, which indicated recurrence. Considering the patient’s age, we performed radiotherapy (50 Gy/25 Fr targeting the pelvic region). At present, 16 months have passed since the completion of radiotherapy. Contrast-enhanced CT shows that the recurrent lymph nodes have disappeared, and no new distant metastasis has been observed.

Conclusions

We reported a case of UPS arising in the rectum. The surgical procedure and indication of preoperative therapy should be carefully selected because complete removal of the tumor is desirable in UPS.

Tyrosine kinase inhibitors in sarcoma treatment

Sarcomas are a group of rare mesenchymal malignant tumors that arise from transformed cells of the mesenchymal connective tissue, which are challenging to treat. The majority of sarcomas are soft tissue sarcomas (STSs; 75%) and this heterogeneous group of tumors is further comprised of gastrointestinal stromal tumors (~15%) and bone sarcomas (10%). Although surgery remains the current primary therapeutic approach for localized disease, recurrent, metastatic and refractory sarcomas require cytotoxic chemotherapy, which usually yields poor results. Therefore the efficiency of sarcoma treatment imposes a difficult problem. Furthermore, even though progress has been made towards understanding the underlying molecular signaling pathways of sarcoma, there are limited treatment options. The aim of the present study was therefore to perform a systematic literature review of the available clinical evidence regarding the role of tyrosine kinase inhibitors (TKIs) in patients with recurrent or refractory STSs and bone sarcomas over the last two decades. Tyrosine kinases are principal elements of several intracellular molecular signaling pathways. Deregulation of these proteins has been implicated in driving oncogenesis via the crosstalk of pivotal cellular signaling pathways and cascades, including cell proliferation, migration, angiogenesis and apoptosis. Subsequently, small molecule TKIs that target these proteins provide a novel potential therapeutic approach for several types of tumor by offering significant clinical benefits. Among the eligible articles, there were 45 prospective clinical trials, primarily multicentric, single arm, phase II and non-randomized. Numerous studies have reported promising results regarding the use of TKIs, mainly resulting in disease control in patients with STSs. The lack of randomized clinical trials demonstrates the ambiguous efficiency of various studied treatment options, which therefore currently limits the approved drugs used in clinical practice. Research both in clinical and preclinical settings is needed to shed light on the underlying molecular drivers of sarcomagenesis and will identify novel therapeutic approaches for pretreated patients.

Molecular targeted therapy for advanced or metastatic soft tissue sarcoma

Soft tissue sarcomas are a form of rare and heterogeneous neoplasms with high recurrence rate and mortality. Over the past decades, less progress has been achieved. Surgical management with or without adjuvant/neoadjuvant radiotherapy is still the first-line treatment for localized soft tissue sarcomas, and chemotherapy is the additional option for those with high-risk. However, not all patients with advanced or metastatic soft tissue sarcomas benefit from conventional chemotherapy, targeted therapy takes the most relevant role in the management of those resistant to or failed to conventional chemotherapy. Heterogeneous soft tissue sarcomas vary from biological behavior, genetic mutations, and clinical presentation with a low incidence, indicating the future direction of histotype-based even molecule-based personalized therapy. Furthermore, increasing preclinical studies were carried out to investigate the pathogenesis and potential therapeutic targets of soft tissue sarcomas and increasing new drugs have been developed in recent years, which had started opening new doors for clinical treatment for patients with advanced/metastatic soft tissue sarcomas. Here we sought to summarize the concise characteristics and advance in the targeted therapy for the most common subtypes of soft tissue sarcomas.

The timing of targeted therapy initiation in metastatic sarcoma as an adjuvant to first-line chemotherapy or a second-line agent

58 cases of metastatic sarcoma were reviewed retrospectively in order to compare the efficacy and safety of concurrent (n=24, group A) versus sequential (n=34, group B) use of chemotherapy and targeted therapy in metastatic sarcoma. Progression-free survival (PFS) 1 was defined as the duration between initiation of first-line treatment to disease progression or recurrence. PFS' was defined as the duration between initiation of first-line treatment to the failure of chemotherapy and targeted therapy, and overall survival (OS) was defined as the duration between initiation of first-line treatment to the date of last follow-up or death. The results revealed that patients in group A possessed a higher tumor burden compared to those in group B (P=0.049). Survival curves revealed that the median PFS1 (15.2 vs. 5.4 months, P=0.000), median PFS' (15.2 vs. 10.8 months, P=0.049), and median OS (42.3 vs. 25.3 months, P=0.041) of subjects in group A were remarkably longer than those of group B. Subgroup analysis showed that patients in group A experienced more favorable PFS1 (15.2 vs. 3 months, P=0.000), PFS' (15.2 vs. 5.8 months, P=0.003), and OS (35.2 vs. 15.7 months, P=0.011) than those in group B, with findings especially prominent in patients with tumor burden ≥ 10 cm in comparison to patients with tumor burden < 10 cm (P ≥ 0.05). All grades of leukopenia, thrombocytopenia, fatigue, and oral mucositis were more frequently diagnosed in patients of group A compared to those of group B. However, there were no significant differences between the rates of Grade 3-4 adverse events between the two groups. This investigation suggests that the concurrent use of targeted therapy and chemotherapy may be useful and safe as a first-line treatment in patients with metastatic sarcoma who possess a high tumor burden.

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 murinedouble 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.

Pharmacotherapy for liposarcoma: current and emerging synthetic treatments

Liposarcomas are rare tumors arising from adipocytic tissue and accounting for approximately 15-20% of all soft tissue sarcomas. Liposarcoma can be further classified into histopathological subtypes with variable chemosensitivity according to subtype. Decisions regarding management should be made on an individual basis, but surgery for localized disease and systemic chemotherapy remain the mainstay of treatment. Currently, only doxorubicin and trabectedin have robust Phase III data to support their use in the management of advanced liposarcoma. However, in the subgroup analysis of a Phase III trial comparing eribulin with dacarbazine, there was a greater than 7-month improvement in median overall survival in those treated with eribulin. There are also promising results from emerging studies in novel and targeted agents for the treatment of liposarcoma.

VEGFR Inhibitors for Uterine Metastatic Perivascular Epithelioid Tumors (PEComa) Resistant to mTOR Inhibitors. A Case Report and Review of Literature

Uterine perivascular epithelioid cell tumors (PEComas) are rare neoplasms. PI3K/AKT/mTOR pathway upregulation is critical for their pathogenesis and is often associated with TSC1/TSC2 inactivation. Although first line mTOR inhibitors are an effective treatment, metastatic PEComas eventually progress. A 53-year-old woman presented a 4-month history of post-menopausal vaginal bleeding. Clinical and radiological examination detected a uterine mass and a single S1 bone lesion. The patient underwent a radical hysterectomy and bone biopsy. The anatomopathological evaluation concluded to an oligo-metastatic uterine PEComa. The tumor harbored a heterozygous deletion of 9q34 that contains the TSC1 gene. Concerning the primary lesion, the resection was complete and the single bone metastasis was treated with radiotherapy. Three months later, the patient presented bone, lung and subcutaneous metastatic progression. An everolimus and denosumab treatment was initiated. After 2 years of treatment, a clinically significant bone, lung and subcutaneous progression was detected. Following a literature review of the possible therapeutic options, we initiated a second line treatment by pazopanib. This treatment resulted in regression of the subcutaneous lesions and stability of lung and bone metastases. In this challenging, rare setting, our report suggests single agent, anti-angiogenic, tyrosine kinase inhibitor to be effective as second line treatment of metastatic uterine PEComa progressing on mTOR inhibitors.

Safety and efficacy of pazopanib as a second-line treatment and beyond for soft tissue sarcomas: A real-life tertiary-center experience in the MENA region

INTRODUCTION

Sarcomas are uncommon malignancies. No advances have been recently achieved despite multiple efforts. Pazopanib is a safe and effective tyrosine kinase inhibitor used in managing soft tissue sarcomas (STS) after chemotherapy failure. However, its use is limited in developing countries and no efficacy data exist from our region. We aimed to study the efficacy of pazopanib in our population, characterized by response rates of patients with chemotherapy-refractory advanced STS receiving pazopanib. Secondary endpoints included progression-free survival (PFS), overall survival (OS) and toxicity profile.

MATERIALS AND METHODS

15 patients (age≥18 year) diagnosed with advanced STS, refractory to first-line chemotherapy, receiving pazopanib as ≥second-line therapy in one tertiary center in Lebanon were included between January 1st, 2014 and October 31st, 2018. Patient and disease characteristics, disease evaluation, as well as tolerance to treatment, were extracted from charts retrospectively. Statistical analysis was done using SPSS version 24.

RESULTS

The mean age was 48.6 [19-66] years. Eleven patients (73.3%) received pazopanib in second-line, whereas four patients (26.7%) received it in third-line. Thirteen patients (86.7%) progressed, and two patients (13.3%) had stable disease. The median PFS was three months [1-19] and the mean OS was 25.4 months [17.2-33.6]. Five patients required dose-reductions due to poor tolerance.

CONCLUSION

Conclusions cannot be drawn due to small patient numbers. However, given the 3-month PFS, 13% of patients maintaining stable disease, and tolerable safety profile, it is reasonable to incorporate pazopanib in STS treatment. More focused studies with larger patient populations need to be done in Lebanon.

Treatment options in unresectable soft tissue and bone sarcoma of the extremities and pelvis - a systematic literature review

In patients with metastatic or unresectable soft tissue and bone sarcoma of extremities and pelvis, survival is generally poor. The aim of the current systematic review was to analyse recent publications on treatment approaches in patients with inoperable and/or metastatic sarcoma.

Original articles published between 1st January 2011 and 2nd May 2020, using the search terms ‘unresectable sarcoma’, ‘inoperability AND sarcoma’, ‘inoperab* AND sarcoma’, and ‘treatment AND unresectable AND sarcoma’ in PubMed, were potentially eligible. Out of the 839 initial articles (containing 274 duplicates) obtained and 23 further articles identified by cross-reference checking, 588 were screened, of which 447 articles were removed not meeting the inclusion criteria. A further 54 articles were excluded following full-text assessment, resulting in 87 articles finally being analysed.

Of the 87 articles, 38 were retrospective (43.7%), two prospective (2.3%), six phase I or I/II trials (6.9%), 22 phase II non-randomized trials (27.6%), nine phase II randomized trials (10.3%) and eight phase III randomized trials (9.2%). Besides radio/particle therapy, isolated limb perfusion and conventional chemotherapy, novel therapeutic approaches, including immune checkpoint inhibitors and tyrosine kinase inhibitors were also identified, with partially very promising effects in advanced sarcomas.

Management of inoperable, advanced or metastatic sarcomas of the pelvis and extremities remains challenging, with the optimal treatment to be defined individually. Besides conventional chemotherapy, some novel therapeutic approaches have promising effects in both bone and soft tissue subtypes. Considering that only a small proportion of studies were randomized, the clinical evidence currently remains moderate and thus calls for further large, randomized clinical trials.

Cite this article: EFORT Open Rev 2020;5:799-814. DOI: 10.1302/2058-5241.5.200069

Novel Therapeutic Insights in Dedifferentiated Liposarcoma: A Role for FGFR and MDM2 Dual Targeting

Simple Summary

Well-differentiated/dedifferentiated liposarcomas (WDLPS/DDLPS) are the most frequent soft tissue sarcomas. Despite the hopes raised by some targeted therapies, effective well-tolerated treatments for DDLPS are still lacking. Small-molecule FGFR inhibitors are currently evaluated in advanced clinical trials including the potent FDA-approved pan-FGFR inhibitor erdafitinib. We provide the first analysis of FGFR1-4 expression and their prognostic value in a series of 694 WDLPS/DDLPS samples. We identified FGFR1 and FGFR4 as prognostic biomarkers. We demonstrated erdafitinib efficacy and showed that erdafitinib combination with the MDM2 antagonist idasanutlin was highly synergistic in vitro and in vivo. The clinical relevance of our findings was supported by our data on a patient with DDLPS refractory to multiple lines of treatment whose tumor was stabilized for 12 weeks on erdafitinib. These data provide a rationale to use FGFR expression as a biomarker to select patients for clinical trials investigating FGFR inhibitors and to test combined erdafitinib and idasanutlin.

Abstract

We aimed to evaluate the therapeutic potential of the pan-FGFR inhibitor erdafitinib to treat dedifferentiated liposarcoma (DDLPS). FGFR expression and their prognostic value were assessed in a series of 694 samples of well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS). The effect of erdafitinib—alone or in combination with other antagonists—on tumorigenicity was evaluated in vitro and in vivo. We detected overexpression of FGFR1 and/or FGFR4 in a subset of WDLPS and DDLPS and demonstrated correlation of this expression with poor prognosis. Erdafitinib treatment reduced cell viability, inducing apoptosis and strong inhibition of the ERK1/2 pathway. Combining erdafitinib with the MDM2 antagonist RG7388 exerted a synergistic effect on viability, apoptosis, and clonogenicity in one WDLPS and two DDLPS cell lines. Efficacy of this combination was confirmed in vivo on a DDLPS xenograft. Importantly, we report the efficacy of erdafitinib in one patient with refractory DDLPS showing disease stabilization for 12 weeks. We provide evidence that the FGFR pathway has therapeutic potential for a subset of DDLPS and that an FGFR1/FGFR4 expression might constitute a powerful biomarker to select patients for FGFR inhibitor clinical trials. In addition, we show that combining erdafitinib with RG7388 is a promising strategy for patients with DDLPS that deserves further investigation in the clinical setting.

Genetic aberrations and molecular biology of cardiac sarcoma

Cardiac tumors are rare and complex entities. Early assessment and differentiation between non-neoplastic and neoplastic masses, be they benign or malignant, is essential for guiding diagnosis, determining prognosis, and planning therapy. Cardiac sarcomas represent the most frequent primary malignant histotype. They could have manifold presentations so that the diagnosis is often belated. Moreover, considering their rarity and the limitation due to the cardiac location itself, the optimal multimodal management of patients affected by primary cardiac sarcomas still remains highly difficult and outcome dismal. Therefore, there is an urgent need to improve these results mainly focusing on more adequate tools for prompt diagnosis and exploring new and more effective therapies. Knowledge about the molecular landscape and pathogenesis of cardiac sarcoma is even more limited due to the rarity of this disease. In this sense, the molecular characterization of heart tumors could unfold potentially novel, druggable targets. In this review, we focused on genetic aberrations and molecular biology of cardiac sarcomas, collecting the scarce information available and resuming all the molecular findings discovered in each tumor subtype, with the aim to get further insights on mechanisms involved in tumor growth and to possibly highlight specific molecular profiles that can be used as diagnostic tests and unveil new clinically actionable targets in this tricky and challenging disease.

Apatinib as targeted therapy for advanced bone and soft tissue sarcoma: a dilemma of reversing multidrug resistance while suffering drug resistance itself

Bone and soft tissue sarcomas are rare malignant tumors originated from mesenchymal tissues. They harbor more than 50 distinct subtypes and differ in pathological features and clinical courses. Despite the significant improvements in modern multi-modality treatment, the outcomes and overall survival rates remain poor for patients with advanced, refractory, metastatic, or relapsed diseases. The growth and metastasis of bone and soft tissue sarcoma largely depend on angiogenesis, and VEGF/VEGFR pathway is considered as the most prominent player in angiogenesis. Therefore, blockade of VEGF/VEGFR pathways is a promising therapeutic strategy to retard neovascularization. Several VEGFR inhibitors have been developed and revealed their favorable anti-neoplastic effects in various cancers, but such desirable anti-tumor effects are not obtained in advanced sarcomas because of multiple reasons, such as drug tolerance, short duration of response, and severe adverse effects. Fortunately, preclinical and clinical studies have indicated that apatinib is a novel promising VEGFR2 inhibitor showing potent anti-angiogenic and anti-neoplastic activities in advanced sarcomas. Especially, apatinib has showed notable characteristics in multidrug resistance reversal, tumor regression, vascular normalization, immunosuppression alleviation, and enhancement of chemotherapeutic and radiotherapeutic effects. However, apatinib also gets struck in dilemma of reversing multidrug resistance of chemotherapeutic agents while suffering drug resistance itself, and several difficulties should be tackled before full use of apatinib. In this review, we discuss the outstanding characteristics and main predicaments of apatinib as targeted therapy in advanced sarcomas. Bone and soft tissue sarcomas are rare but malignant tumors originated from mesenchymal tissues. They harbor more than 100 distinct subtypes and differ in features of pathologies and clinical courses. Despite the significant improvements in modern multi-modality treatment, the outcomes and overall survival rates remain poor for patients with advanced, refractory, metastatic, or relapsed lesions. The growth and metastasis of bone and soft tissue sarcoma largely depend on angiogenesis and VEGF/VEGFR pathways play a pivotal role in angiogenesis. Therefore, blockade of VEGF/VEGFR pathways is a promising therapeutic strategy. Several VEGFR inhibitors have been developed and verified in clinical trials but with unfavorable outcomes. Fortunately, preclinical studies and clinical trials have indicated that apatinib is a novel promising VEGFR2 inhibitor showing potent anti-angiogenic and anti-neoplastic activities in advanced sarcomas. Actually, apatinib has showed notable characteristics in multidrug resistance reversal, tumor regression, vascular normalization, immunosuppression alleviation, enhancement of chemotherapeutic and radiotherapeutic effects. However, apatinib also gets struck in dilemma of reversing multidrug resistance of chemotherapeutic agents while suffering drug resistance itself, and several difficulties should be tackled before full use of apatinib. In this review, we discuss the outstanding characteristics and main predicaments of apatinib as targeted therapy in advanced sarcomas.

Therapeutic Implication of Genomic Landscape of Adult Metastatic Sarcoma

PURPOSE

This study investigated therapeutic potential of integrated genome and transcriptome profiling of metastatic sarcoma, a rare but extremely heterogeneous group of aggressive mesenchymal malignancies with few systemic therapeutic options.

METHODS

Forty-three adult patients with advanced or metastatic non-GI stromal tumor sarcomas of various histology subtypes who were enrolled in the Personalized OncoGenomics program at BC Cancer were included in this study. Fresh tumor tissues along with blood samples underwent whole-genome and transcriptome sequencing.

RESULTS

The most frequent genomic alterations in this cohort are large-scale structural variation and somatic copy number variation. Outlier RNA expression as well as somatic copy number variations, structural variations, and small mutations together suggest the presence of one or more potential therapeutic targets in the majority of patients in our cohort. Point mutations or deletions in known targetable cancer genes are rare; for example, tuberous sclerosis complex 2 provides a rationale for targeting the mammalian target of rapamycin pathway, resulting in a few patients with exceptional clinical benefit from everolimus. In addition, we observed recurrent 17p11-12 amplifications, which seem to be a sarcoma-specific event. This may suggest that this region harbors an oncogene(s) that is significant for sarcoma tumorigenesis. Furthermore, some sarcoma tumors carrying a distinct mutational signature suggestive of homologous recombination deficiency seem to demonstrate sensitivity to double-strand DNA-damaging agents.

CONCLUSION

Integrated large-scale genomic analysis may provide insights into potential therapeutic targets as well as novel biologic features of metastatic sarcomas that could fuel future experimental and clinical research and help design biomarker-driven basket clinical trials for novel therapeutic strategies.

Atypical Presentation of Renal Leiomyosarcoma: A Case Report

Primary renal sarcomas are rare comprising from 0.8 to 2.7% of adult renal tumours. They cannot be distinguished clinically or radiologically from the more common renal cell carcinomas. Leiomyosarcoma is the most common histological subtype accounting for around 50-60% of renal sarcomas. Leiomyosarcomas arise from the renal capsule, renal vein or the renal pelvis. They present with nonspecific clinical symptoms and signs and usually have a dismal outcome. Rarely atypical presentations such as acute tumour rupture and hematuria are encountered. We report a 27-year-old woman who presented with malignant hypertension. The hypertension was controlled emergently with antihypertensive agents. In view of the young age, a thorough workup was conducted to identify the cause of hypertension. Imaging studies revealed a solid enhancing renal tumour compressing the renal vasculature. As the staging workup did not reveal any evidence of metastases, the patient underwent right-sided open radical nephrectomy after adequate control of hypertension. The histological examination uncovered the renal tumour to be a leiomyosarcoma. Postoperative period was uneventful and she was doing well on one year follow up. Surprisingly the blood pressure normalised postoperatively and the patient was weaned off of her antihypertensive medications. This case is presented to highlight the atypical acute presentation of primary renal leiomyosarcoma with relatively good prognosis. Timely diagnosis and meticulous surgical resection improved the prognosis of this aggressive renal malignancy.

Safety and Tolerability of Anti-Angiogenic Protein Kinase Inhibitors and Vascular-Disrupting Agents in Cancer: Focus on Gastrointestinal Malignancies

Angiogenesis is an essential process for tumor growth and metastasis. Inhibition of angiogenesis as an anticancer strategy has shown significant results in a plethora of tumors. Anti-angiogenic agents are currently part of many standard-of-care options for several metastatic gastrointestinal cancers. Bevacizumab, aflibercept, ramucirumab, and regorafenib have significantly improved both progression-free and overall survival in different lines of treatment in metastatic colorectal cancer. Second-line ramucirumab and third-line apatinib are effective anti-angiogenic treatments for patients with metastatic gastric cancer. Unfortunately, the anti-angiogenic strategy has major practical limitations: resistance inevitably develops through redundancy of signaling pathways and selection for subclonal populations adapted for hypoxic conditions. Anti-angiogenic agents may be more effective in combination therapies, with not only cytotoxics but also other emerging compounds in the anti-angiogenic class or in the separate class of the so-called vascular-disrupting agents. This review aims to provide an overview of the approved and "under development" anti-angiogenic compounds as well as the vascular-disrupting agents in the treatment of gastrointestinal cancers, focusing on the actual body of knowledge available on therapy challenges, pharmacodynamic and pharmacokinetic mechanisms, safety profiles, promising predictive biomarkers, and future perspectives.

Pharmacotherapy for liposarcoma: current state of the art and emerging systemic treatments

Introduction: Liposarcomas are a heterogeneous group of soft tissue tumors that arise from adipose tissue and are one of the most common soft tissue sarcomas found in adults. Liposarcomas are subclassified into four subtypes with distinct histologic and biologic features that influence their treatment and management. Areas covered: This manuscript reviews the key clinicopathologic and cytogenic characteristics of the liposarcoma histologic subtypes and summarizes the results of recent clinical trials, treatment options, and future directions in the pharmacotherapy for the management of liposarcoma. Expert opinion: Despite significant advancements in the management of this disease, the treatment of liposarcoma continues to be a challenge. Surgical resection remains the mainstay of treatment for localized disease; however, use of systemic therapies in conjunction with surgery may be considered in patients where tumor shrinkage could reduce surgical morbidity and in patients with high-risk of micrometastatic disease. Anthracycline-based chemotherapy regimens remain the standard first-line treatment for unresectable/metastatic liposarcoma. Trabectedin and eribulin are currently the two most promising and evidenced-based second-line treatment options for liposarcomas. However, multiple clinical trials dedicated to patients with liposarcoma evaluating novel targeted agents are ongoing. Every effort should be made to enroll patients with liposarcoma into histotype-specific clinical trials.

Efficacy and safety of apatinib in treatment of osteosarcoma after failed standard multimodal therapy: An observational study

Recently, apatinib has been shown to be effective in treating sarcoma. This study aimed to assess the safety and efficacy of apatinib in the treatment of patients with osteosarcoma after failed of standard multimodal therapy and to compare the therapeutic effects of apatinib on osteosarcoma between high-dose group and low-dose group.A total of 27 patients with osteosarcoma who received apatinib between January 2016 and August 2017 were retrospectively reviewed. Among the 27 patients, the objective response rate (ORR) and the disease control rate (DCR) were 25.93% and 66.67%, respectively. The median of progression-free survival (m-PFS) was 3.5 months (95% confidence interval [CI], 2.5-4.8 months), and the median of overall survival (m-OS) was 9.5 months (95% CI, 7.8-10.5 months). There was no statistically significant difference in ORR (36.36% vs 18.75%), DCR (63.64% vs 68.75%), m-PFS (4.3 months [95% CI, 1.8-7 months) vs 3.35 months (95% CI, 1.8-4 months]), and m-OS (9.5 months [95% CI, 7.8-10.5 months] vs 9.4 months [95% CI, 7.8-10.8 months]) (P > .05) between the high-dose group (the average dose was 659 mg/qd) and the low-dose group (the average dose was 516 mg/qd). Most of the adverse events (AEs) were in grade 1 or grade 2. The main AEs in grade 3 were hypertension, rash, weight loss, hand-foot syndrome, and diarrhea.Apatinib is safe and effective in the treatment of advanced osteosarcoma. We recommend that the initial dose of apatinib should be 500 mg/qd in the treatment of osteosarcoma.

miR-193b regulates tumorigenesis in liposarcoma cells via PDGFR, TGFβ, and Wnt signaling

Liposarcoma is the most common soft tissue sarcoma. Molecularly targeted therapeutics have had limited efficacy in liposarcomas, in part because of inadequate knowledge of the complex molecular alterations in these tumors. Our recent study revealed the tumor suppressive function of miR-193b in liposarcoma. Considering the biological and clinical heterogeneity of liposarcoma, here, we confirmed the under-expression of miR-193b in additional patient liposarcoma samples and cell lines. Based on STRING analysis of protein-protein interactions among the reported putative miR-193b targets, we validated three: PDGFRβ, SMAD4, and YAP1, belonging to strongly interacting pathways (focal adhesion, TGFβ, and Hippo, respectively). We show that all three are directly targeted by miR-193b in liposarcoma. Inhibition of PDGFRβ reduces liposarcoma cell viability and increases adipogenesis. Knockdown of SMAD4 promotes adipogenic differentiation. miR-193b targeting of the Hippo signaling effector YAP1 indirectly inhibits Wnt/β-catenin signaling. Both a PDGFR inhibitor (CP-673451) and a Wnt/ β-catenin inhibitor (ICG-001) had potent inhibitory effects on liposarcoma cells, suggesting their potential application in liposarcoma treatment. In summary, we demonstrate that miR-193b controls cell growth and differentiation in liposarcoma by targeting multiple key components (PDGFRβ, SMAD4, and YAP1) in several oncogenic signaling pathways.

Systemic Treatment of Metastatic/Recurrent Uterine Leiomyosarcoma: A Changing Paradigm

The treatment of metastatic and recurrent uterine leoimyosarcoma (uLMS) has evolved rapidly in the past several years. Leoimyosarcoma is extremely aggressive and responds poorly to traditional chemotherapeutics. Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these new compounds. Additionally, the potential role of immunotherapy is being assessed in current uLMS clinical trials. Given the increasing number of agents available both in the U.S. and globally, a treatment template that addresses optimal sequencing based upon expert consensus would be useful. Current guidelines, although listing various options, lack granularity by line of therapy. Most patients with leiomyosarcoma, even in early stage, are treated with surgery followed by adjuvant chemotherapy despite uLMS being relatively chemoresistant. Adjuvant chemotherapy often includes the combination of gemcitabine and docetaxel with or without doxorubicin in first-line systemic therapy, but these cytotoxic agents only provide patients with advanced disease a 5-year survival <30%. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uLMS. Critical ongoing studies investigating novel approaches including immunotherapeutics and genetic alterations also will be discussed. IMPLICATIONS FOR PRACTICE: Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these compounds. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uterine leoimyosarcoma.

Treatment-related adverse effects with pazopanib, sorafenib and sunitinib in patients with advanced soft tissue sarcoma: a pooled analysis

Objective

Research efforts have investigated therapies targeting tyrosine kinase signaling pathways. We performed a pooled analysis to determine the frequency of severe adverse effects in patients with soft tissue sarcoma treated with pazopanib, sorafenib and sunitinib.

Materials and methods

We performed a comprehensive search of PubMed, Web of Science, Ovid, the Cochrane Library and Embase databases from the drugs’ inception to May 2017 to identify clinical trials. All-grade and severe adverse events (AEs; grade≥3) were analyzed.

Results

A total of 10 trials published between 2009 and 2016, including 843 patients, were eligible for analysis. We included 424 patients (three studies) who received pazopanib 800 mg daily, 353 patients (five studies) who received sorafenib 400 mg twice daily and 66 patients (two studies) who received sunitinib 37.5 mg daily. The incidence of AEs is different among the three VEGFR-tyrosine kinase inhibitors (TKIs). Pazopanib showed higher incidence of all-grade nausea, diarrhea and hypertension compared with sorafenib and sunitinib. However, patients in the sorafenib group experienced a significantly higher frequency of all-grade rash (26.1%), hand–foot syndrome (33.4%) and mucositis (38.5%). The difference was highly significant for sorafenib vs. pazopanib in the incidence of all-grade rash (odds ratio [OR] 1.649, 95% CI 1.086–2.505, P=0.023), hand–foot syndrome (OR 3.096, 95% CI 1.271–7.544, P=0.009) and mucositis (OR 4.562, 95% CI 2.132–9.609, P<0.001). Moreover, the frequency of grade ≥3 mucositis was significantly higher in the sunitinib group compared with the pazopanib or sorafenib group (7.6% vs. 1.3%, OR 6.448, 95% CI 1.499–27.731, P=0.013).

Conclusion

Statistically significant differences in certain common adverse effects, such as all-grade and severe AEs, were detected among pazopanib, sorafenib and sunitinib in the current study. Early and prompt management is critically needed to avoid unnecessary dose reductions and treatment-related discontinuations.

Positive correlation between the density of macrophages and T-cells in undifferentiated sarcoma

Undifferentiated sarcoma (US) is a frequent soft tissue sarcoma. Although the 10-year survival rate is around 60%, advanced US is highly resistant to chemo/radiotherapy. The tumor microenvironment (TME) is closely associated with tumor progression. However, few studies of infiltrated immune cells in US have been published. In this study, we evaluated tumor-associated macrophages (TAMs) and CD8-positive cytotoxic T lymphocytes (CTLs) in 28 cases of US. Iba1, CD163, and CD204 were used as markers for TAMs. The density of CTLs was positively correlated with the density of TAMs. However, a negative correlation was seen between the density of CTLs and the percentage of CD204-positive TAMs. We found no significant association between the density of Iba1-/CD204-/CD8-positive cells and clinicopathological factors. No significant correlation between immune cell infiltration and clinical outcome was observed. Although we found no significant association between immune cells and clinicopathological factors, these findings may provide new insight into the characterization of immune cells in the TME of US.

Current Molecular Targeted Therapies for Bone and Soft Tissue Sarcomas

Systemic treatment options for bone and soft tissue sarcomas remained unchanged until the 2000s. These cancers presented challenges in new drug development partly because of their rarity and heterogeneity. Many new molecular targeting drugs have been tried in the 2010s, and some were approved for bone and soft tissue sarcoma. As one of the first molecular targeted drugs approved for solid malignant tumors, imatinib's approval as a treatment for gastrointestinal stromal tumors (GISTs) has been a great achievement. Following imatinib, other tyrosine kinase inhibitors (TKIs) have been approved for GISTs such as sunitinib and regorafenib, and pazopanib was approved for non-GIST soft tissue sarcomas. Olaratumab, the monoclonal antibody that targets platelet-derived growth factor receptor (PDGFR)-α, was shown to extend the overall survival of soft tissue sarcoma patients and was approved in 2016 in the U.S. as a breakthrough therapy. For bone tumors, new drugs are limited to denosumab, a receptor activator of nuclear factor κB ligand (RANKL) inhibitor, for treating giant cell tumors of bone. In this review, we explain and summarize the current molecular targeting therapies approved and in development for bone and soft tissue sarcomas.

Efficacy and safety of apatinib monotherapy in advanced bone and soft tissue sarcoma: An observational study

Sarcomas are rare but malignant tumors with high risks of local recurrence and distant metastasis. Anti-angiogenic therapy is a potential strategy against un-controlled and not-organized tumor angiogenesis. We aimed to assess the safety and efficacy of apatinib, an oral tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2, in patients with advanced sarcoma. Thirty-one patients who received initial apatinib between September 2015 and August 2016 were retrospectively reviewed. Among them, 19 (61.3%) patients were heavily pretreated with two or more lines of cytotoxic chemotherapy. Apatinib was given at a start-dose of 425 mg qd. During therapy, 9 (29.0%) patients required dose interruption and 7 (22.6%) needed dose reduction, and the mean dosage of apatinib was 372.9 ± 68.4 mg/day. In the study cohort, one patient was treated as adjunctive therapy and 6 patients stopped treatment before radiographic response assessment. Thus, 24 patients were eligible for tumor response evaluation. The objective response rate was 33.3% and clinical benefit rate was as high as 75.0%. The progression free survival was 4.25 (95% confidence interval [CI], 2.22-5.11) months, whereas the overall survival was 9.43 (95% CI, 6.64-18.72) months. Compared with other histological subtypes, leiomyosarcoma did not show significant survival benefits. Most of the adverse events (AEs) were at grade 1 or 2. The main grade 3 AEs were hypertension (6.5%), hand foot skin reaction (6.5%), and diarrhea (3.2%). In conclusion, apatinib showed promising efficacy and acceptable safety profile in metastatic or recurrent sarcoma, giving rationale clinical evidence to conduct clinical trials.

Radiotherapy in soft-tissue sarcoma of the extremities

Sarcomas are an infrequent and heterogeneous group of neoplasia. Surgery with or without associated radiotherapy (RT) is the basic treatment for this type of tumour. To increase the therapeutic ratio (the index between cytotoxic effects in tumours and normal tissue complications with a certain dose of radiation), new advances are being investigated to increase local and distant control and to decrease the morbidity of the treatment. The aim of this review was to analyse the different strategies, based on technology and biology, which are being investigated to increase the therapeutic ratio of this disease.

Clinical and Molecular Spectrum of Liposarcoma

Liposarcomas are rare malignant tumors of adipocytic differentiation. The classification of liposarcomas into four principal subtypes reflects the distinct clinical behavior, treatment sensitivity, and underlying biology encompassed by these diseases. Increasingly, clinical management decisions and the development of investigational therapeutics are informed by an improved understanding of subtype-specific molecular pathology. Well-differentiated liposarcoma is the most common subtype and is associated with indolent behavior, local recurrence, and insensitivity to radiotherapy and chemotherapy. Dedifferentiated liposarcoma represents focal progression of well-differentiated disease into a more aggressive, metastasizing, and fatal malignancy. Both of these subtypes are characterized by recurrent amplifications within chromosome 12, resulting in the overexpression of disease-driving genes that have been the focus of therapeutic targeting. Myxoid liposarcoma is characterized by a pathognomonic chromosomal translocation that results in an oncogenic fusion protein, whereas pleomorphic liposarcoma is a karyotypically complex and especially poor-prognosis subtype that accounts for less than 10% of liposarcoma diagnoses. A range of novel pharmaceutical agents that aim to target liposarcoma-specific biology are under active investigation and offer hope of adding to the limited available treatment options for recurrent or inoperable disease.

Systemic Therapy in Metastatic or Unresectable Well-Differentiated/Dedifferentiated Liposarcoma

Liposarcoma is one of the most common subtypes of soft-tissue sarcoma and consists of three main subtypes, of which well-differentiated liposarcoma and dedifferentiated liposarcoma account for 40–45%. The current mainstay of systemic treatment for patients with metastatic or unresectable disease remains doxorubicin with or without ifosfamide in the first-line setting. Recently, eribulin and trabectedin have been approved by the US Food and Drug Administration for recurrent liposarcomas and progress in molecular characterization of these tumors has opened up new and potential novel treatment targets. This review will focus on the evidence base for current treatment strategies and will also discuss potential future options.

Kinase profiling of liposarcomas using RNAi and drug screening assays identified druggable targets

BACKGROUND

Liposarcoma, the most common soft tissue tumor, is understudied cancer, and limited progress has been made in the treatment of metastatic disease. The Achilles heel of cancer often is their kinases that are excellent therapeutic targets. However, very limited knowledge exists of therapeutic critical kinase targets in liposarcoma that could be potentially used in disease management.

METHODS

Large RNAi and small-molecule tyrosine kinase inhibitor screens were performed against the proliferative capacity of liposarcoma cell lines of different subtypes. Each small molecule inhibitor was either FDA approved or in a clinical trial.

RESULTS

Screening assays identified several previously unrecognized targets including PTK2 and KIT in liposarcoma. We also observed that ponatinib, multi-targeted tyrosine kinase inhibitor, was the most effective drug with anti-growth effects against all cell lines. In vitro assays showed that ponatinib inhibited the clonogenic proliferation of liposarcoma, and this anti-growth effect was associated with apoptosis and cell cycle arrest at the G0/G1 phase as well as a decrease in the KIT signaling pathway. In addition, ponatinib inhibited in vivo growth of liposarcoma in a xenograft model.

CONCLUSIONS

Two large-scale kinase screenings identified novel liposarcoma targets and a FDA-approved inhibitor, ponatinib with clear anti-liposarcoma activity highlighting its potential therapy for treatment of this deadly tumor.

The role of pazopanib on tumour angiogenesis and in the management of cancers: A review

Pazopanib is a relatively new compound to be introduced into the chemotherapy field. It is thought to have decent anti-angiogenic properties, which gives an additional hope for the treatment of certain types of cancers. A systematic review solely discussing about pazopanib and its anti-angiogenic effect is yet to be published to date, despite several relevant clinical trials being conducted over the recent years. In this review, we aim to investigate the mechanism of pazopanib's anti-angiogenic effect and its effectiveness in treating several cancers. We have included, in this study, findings from electronically searchable data from randomized clinical trials, clinical studies, cohort studies and other relevant articles. A total of 352 studies were included in this review. From the studies, the effect of pazopanib in various cancers or models was observed and recorded. Study quality is indefinite, with a few decent quality articles. The most elaborately studied cancers include renal cell carcinoma, solid tumors, advanced solid tumors, soft tissue sarcoma, breast cancer and gynecological cancers. In addition, several less commonly studied cancers are included in the studies as well. Pazopanib had demonstrated its anti-angiogenic effect based on favorable results observed in cancers, which are caused by angiogenesis-related mechanisms, such as renal cell carcinoma, solid tumors, advanced solid tumors and soft tissue sarcoma. This review was conducted to study, analyze and review the anti-angiogenic properties of pazopanib in various cancers. The results obtained can provide a decent reference when considering treatment options for angiogenesis-related malignancies. Furthermore, the definite observations of the anti-angiogenic effects of pazopanib could provide newer insights leading to the future development of drugs of the same mechanism with increased efficiency and reduced adverse effects.

Effective apatinib treatment of pleomorphic liposarcoma: A case report

RATIONALE

Pleomorphic liposarcoma (PLS) is a rare and aggressive malignant tumor, and both radiation and conventional cytotoxic chemotherapy remain controversial for metastatic or unresectable disease.

PATIENT CONCERNS

We presented an 81-year-old Chinese woman with advanced PLS who received apatinib after failure chemotherapy.

DIAGNOSES

The patient was diagnosed as having PLS by biopsy.

INTERVENTIONS

After a failed chemotherapy, apatinib started to be taken orally 425 mg per day.

OUTCOMES

This patient achieved 3-month progression-free survival (PFS) and a higher quality of life. Meanwhile, this patient suffered grade 2 hypertension and grade 3 hand-foot syndrome (HFS).

LESSONS

In this case, apatinib presented good efficacy and safety to treat PLS. Randomized clinical studies are required to confirm the efficacy and safety of apatinib in the treatment of PLS.

Successful treatment of advanced pancreatic liposarcoma with apatinib: A case report and literature review

Pancreatic liposarcoma is a malignant tumor originated from the pancreas mesenchymal tissue and mostly presented in skin, subcutaneous, periosteum, and long bone on both sides. Both conventional chemotherapy and radiotherapy have limited efficacy and poor prognosis for advanced pancreatic liposarcoma. Here, we reported a case of advanced pancreatic liposarcoma and reviewed the literature specific for liposarcoma of the pancreas and discuss the emerging options of treatment. The patient was treated with apatinib and a cross-line rescue therapy combined with paclitaxel after progressive disease. The therapeutic effect of the combination regimen has been evaluated. Apatinib is an oral tyrosine kinase inhibitor targeting the intracellular domain of vascular endothelial growth factor receptor-2 (VEGFR-2), which has dual effects of anti-angiogenesis and anti-tumor cell proliferation. To our knowledge, this is the first case to report the successful use of apatinib for advanced pancreatic liposarcoma.

A phase II study of tivozanib in patients with metastatic and nonresectable soft-tissue sarcomas

Background

Soft tissue sarcomas (STSs) overexpress vascular endothelial growth factors (VEGF) and VEGF-receptors (VEGFR) activation have been associated with tumor aggressiveness. Tivozanib is a potent small molecule tyrosine kinase inhibitor against VEGFR1-3, with activity against PDGFRα/β and cKIT. The primary endpoint of this study was progression free survival (PFS) rate at 16 weeks. Secondary end points were overall survival (OS), response rate, safety and correlative studies.

Patients and methods

A Simon two-stage phase II trial was performed using tivozanib given orally at 1.5 mg daily, 3 week on 1 week off on a 28 day cycle until disease progression or intolerable toxicity.

Results

Fifty-eight patients were enrolled and treated with tivozanib. Leiomyosarcoma was the most common STS histological type in our cohort (47%) and 27 patients (46%) had received at least 3 lines of therapy prior to study entry. Up to 24 patients (41%) had prior VEGF targeted therapies. Partial response and stable disease were observed in 2 (3.6%) and 30 (54.5%) patients. The 16 week PFS rate was 36.4% [95% confidence interval (CI) 23.7-49.1] and a median PFS of 3.5 months (95% CI 1.8-3). Median OS observed was 12.2 months (95% CI 8.1-16.8). The most frequent all grade toxicities were fatigue (48.3%), hypertension (43.1%), nausea (31%) and diarrhea (27.6%). The most common grade three toxicity was hypertension (22.4%). Correlative studies demonstrate no correlation between the expression of VEGFR 1, 2 or 3, PDGFRα/β or FGF, and activity of tivozanib.

Conclusion

Tivozanib was well tolerated and showed antitumor activity with a promising median PFS and PFS rate at 4 months in a heavily pretreated population of metastatic STSs. Our results support further studies to assess the clinical efficacy of tivozanib in STS.

Clinical Trial Number

NCT01782313.

Pharmacological therapies for Liposarcoma

INTRODUCTION

Liposarcoma (LS) is one of the most common adult soft tissue sarcomas (STS). For metastatic disease, systemic treatment options were historically represented by standard cytotoxic chemotherapy. More recently, innovative therapies have been introduced and they are currently part of the therapeutic armamentarium, positively impacting disease control and patients' quality of life. Moreover, in the last decade, a better understanding of the molecular characteristics of each STS subtype allowed to detect new potential targets and develop novel, biology-driven compounds at different stages of testing. Areas covered: This review is focused on LS, retracing their pharmacological management, starting with a summary of results achieved with standard chemotherapy, then moving to a deeper analysis on data obtained with new, approved therapies and finally reporting an update on ongoing clinical trials, thus providing an overview on the current scenario and outlining how it might evolve in the coming years. Expert commentary: Important strides have been made in the knowledge and treatment of LS. Peculiar molecular features and fundamental signalling pathways represent nowadays druggable targets for novel therapies. However, predictive biomarkers still need to be identified in order to better select the target population, to possibly test combinations of drugs, with the ultimate goal of improving outcomes.

Newer medical therapies for metastatic soft tissue sarcoma

INTRODUCTION

Metastatic/advanced soft tissue sarcoma has a poor prognosis conventionally, treatment options have been limited. In recent years, this area has been a rich ground for research with many new drugs being approved and several more in the pipeline. With multiple new treatment options available, it is vital to keep up pace with this rapidly changing field. Areas covered: Recent data regarding use of novel agents in advanced soft tissue sarcoma is reviewed with a focus on clinical applicability. The goal is to guide the clinician into choosing appropriate lines of therapy for the individual patient in light of recent availability of multiple new treatment options. Expert commentary: Patients with advanced soft tissue sarcoma can expect to receive several lines of therapy in the modern era. Tumor histology should ideally guide the choice of therapy. The new FDA approved second line drugs viz, trabectedin, pazopanib and eribulin should be considered first after failure of doxorubicin-based chemotherapy. Additional options have become available, such as antiangiogenic agents, mTOR inhibitors, and several new molecules targeting specific oncogenic pathways. All these agents have a role in treating soft tissue sarcoma, and careful individualization of therapy can help achieve optimal outcomes in these challenging patients.

Targeting Angiogenesis in Colorectal Cancer: Tyrosine Kinase Inhibitors

Colorectal cancer is commonly diagnosed throughout the world, and treatment options have greatly expanded over the last 2 decades. Targeting angiogenesis has been a major focus of study in a variety of malignancy types. Targeting angiogenesis has been achieved by several mechanisms in colorectal cancer, including use of antiangiogenic small molecule tyrosine kinase inhibitors (TKIs). There have been many attempts and failures to prove efficacy of TKIs in the treatment of colorectal cancer including sorafenib, sunitinib, vatalanib, and tivozanib. Regorafenib was the first TKI to demonstrate efficacy and is an orally active inhibitor of angiogenic (including the vascular endothelial growth factor receptors 1, 2, and 3), stromal, and oncogenic receptor tyrosine kinases. There are ongoing investigations of both regorafenib and ninetanib; however, there remains a critical need to better understand novel combinations with TKIs that could prove more efficacious than available options.

Current classification, treatment options, and new perspectives in the management of adipocytic sarcomas

Sarcomas are a heterogeneous group of mesenchymal tumors arising from soft tissue or bone, with an uncertain etiology and difficult classification. Soft tissue sarcomas (STSs) account for around 1% of all adult cancers. Till date, more than 50 histologic subtypes have been identified. Adipocyte sarcoma or liposarcoma (LPS) is one of the most common STS subtypes, accounting for 15% of all sarcomas, with an incidence of 24% of all extremity STSs and 45% of all retroperitoneal STSs. The new World Health Organization classification system has divided LPS into four different subgroups: atypical lipomatous tumor/well-differentiated LPS, dedifferentiated LPS, myxoid LPS, and pleomorphic LPS. These lesions can develop at any location and exhibit different aggressive potentials reflecting their morphologic diversity and clinical behavior. Patients affected by LPS should be managed in specialized multidisciplinary cancer centers. Whereas surgical resection is the mainstay of treatment for localized disease, the benefits of adjuvant and neoadjuvant chemotherapy are still unclear. Systemic treatment, particularly chemotherapy, is still limited in metastatic disease. Despite the efforts toward a better understanding of the biology of LPS, the outcome of advanced and metastatic patients remains poor. The advent of targeted therapies may lead to an improvement of treatment options and clinical outcomes. A larger patient enrollment into translational and clinical studies will help increase the knowledge of the biological behavior of LPSs, test new drugs, and introduce new methodological studies, that is, on treatment response.

Histology-Specific Uses of Tyrosine Kinase Inhibitors in Non-gastrointestinal Stromal Tumor Sarcomas

OPINION STATEMENT

Adult sarcomas, especially those with metastatic or unresectable disease, have limited treatment options. Traditional chemotherapeutic options have been limited by poor response rates in patients with advanced sarcomas. The important clinical question is whether the success of targeted therapy in GIST can be extended to other sarcomas and also if preclinical data describing targets across this heterogeneous group of cancers can be translated to clinical efficacy of known and upcoming target specific agents. Multi-targeted tyrosine kinase inhibitors (TKI) such as pazopanib, sorafenib, sunutinib, cediranib have shown benefits across various histologies of soft tissue sarcoma as well as bone sarcomas. The efficacy of imatinib in Dermatofibrosarcoma Protruberans; sunitinib and cediranib in alveolar soft part sarcoma; and sorafenib and imatinib in chordomas have provided a treatment option of these rare tumors where no effective options existed. TKIs are being tested in combination with chemotherapy as well as radiation to improve response. Although traditional RECIST criteria may not adequately reflect response to these targeted agents, the studies have shown promise for the efficacy of TKIs across the spectrum of sarcomas. The integration of biomarker studies with clinical trials may help further identify responders beyond that defined by histology. With the current data, TKIs are being used both as first-line treatment and beyond in non-GIST sarcomas.

Significant partial response of metastatic intra-abdominal and pelvic round cell liposarcoma to a small-molecule VEGFR-2 tyrosine kinase inhibitor apatinib: A case report

INTRODUCTION

Myxoid/round cell liposarcoma is the second most common subtype of liposarcoma. Chemotherapy and radiotherapy have a limited efficacy for treating advanced myxoid/round cell liposarcoma, with relatively serious side effects.

CASE PRESENTATION

We herein present a 68-year-old Chinese woman initially diagnosed with advanced multiple intra-abdominal and pelvic round cell liposarcoma.She refused to receive cytotoxic chemotherapy and received apatinib as the first-line therapy, a novel tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2 that has been used in the treatment of patients with metastatic gastric cancer who progressed with 2 or more chemotherapy regimens. This patient was partially responsive to apatinib with a dose of 500 mg daily. No serious drug-related side effects were observed.

CONCLUSION

Our findings indicate that some cases of liposarcoma may be responsive to antiangiogenic agent apatinib. Randomized clinical studies are needed to further confirm the efficacy and safety of apatinib in the clinical treatment of liposarcoma.

Pazopanib in the management of advanced soft tissue sarcomas

Therapy of soft tissue sarcomas represents an area of significant unmet need in oncology. Angiogenesis has been explored as a potential target both preclinically and clinically, with suggestions of activity. Pazopanib is a multitargeted tyrosine kinase inhibitor with prominent antiangiogenic effects. In a Phase II study, pazopanib demonstrated activity in strata enrolling patients with leiomyosarcomas, synovial sarcomas, or other sarcomas but not those enrolling adipocytic sarcomas. PALETTE, the pivotal Phase III trial, demonstrated improved progression-free survival versus placebo in pazopanib-treated patients previously treated for advanced soft tissue sarcomas. No survival benefit was observed, and adipocytic sarcomas were excluded. Health-related quality-of-life assessments indicated significant decrements in several areas affected by pazopanib toxicities, but no global deterioration. Cost-effectiveness analyses indicate that pazopanib therapy may or may not be cost-effective in different geographic settings. Pazopanib provides important proof-of-concept for antiangiogenic therapy in soft tissue sarcomas. Its use can be improved by further biological studies of its activity profile in sarcomas, studies of biological rational combinations, and clinicopathologic/biological correlative studies of activity to allow better drug targeting.

Benefit, Risk, and Outcomes in Drug Development: A Systematic Review of Sunitinib

BACKGROUND

Little is known about the total patient burden associated with clinical development and where burdens fall most heavily during a drug development program. Our goal was to quantify the total patient burden/benefit in developing a new drug.

METHODS

We measured risk using drug-related adverse events that were grade 3 or higher, benefit by objective response rate, and trial outcomes by whether studies met their primary endpoint with acceptable safety. The differences in risk (death rate) and benefit (overall response rate) between industry and nonindustry trials were analyzed with an inverse-variance weighted fixed effects meta-analysis implemented as a weighted regression analysis. All statistical tests were two-sided.

RESULTS

We identified 103 primary publications of sunitinib monotherapy, representing 9092 patients and 3991 patient-years of involvement over 10 years and 32 different malignancies. In total, 1052 patients receiving sunitinib monotherapy experienced objective tumor response (15.7% of intent-to-treat population, 95% confidence interval [CI] = 15.3% to 16.0%), 98 died from drug-related toxicities (1.08%, 95% CI = 1.02% to 1.14%), and at least 1245 experienced grade 3-4 drug-related toxicities (13.7%, 95% CI = 13.3% to 14.1%). Risk/benefit worsened as the development program matured, with several instances of replicated negative studies and almost no positive trials after the first responding malignancies were discovered.

CONCLUSIONS

Even for a successful drug, the risk/benefit balance of trials was similar to phase I cancer trials in general. Sunitinib monotherapy development showed worsening risk/benefit, and the testing of new indications responded slowly to evidence that sunitinib monotherapy would not extend to new malignancies. Research decision-making should draw on evidence from whole research programs rather than a narrow band of studies in the same indication.

Off-label use of targeted therapies in osteosarcomas: data from the French registry OUTC'S (Observatoire de l'Utilisation des Thérapies Ciblées dans les Sarcomes)

Background

The objective of this study is to explore the off-label use of targeted therapies (TTs) for patients with osteosarcoma registered within the French Sarcoma Group – Bone Tumor Study Group (GSF-GETO) national registry.

Methods

All patients with an osteosarcoma, registered between January 1, 2009 and July 15, 2013 were analyzed.

Results

Twenty-nine patients with refractory relapsed osteosarcomas received 33 treatment lines of TTs. The median age at the beginning of treatment was 19 years (range 9–72). The median number of previous lines of chemotherapy was 3 (range 1–8). Before inclusion, 3 patients were in second complete remission, 26 were in progression for metastatic relapse. Twenty-three patients received sirolimus (in combination with cyclophosphamide for 18); 5, sunitinib; 4, sorafenib; and one, pazopanib. Stable disease was observed for 45.5 % of patients (95 % Confidence Interval (CI) [20–52.8]). The median Progression-Free Survival (PFS) was 3 months (95 % CI [2–5.4]) for patients treated by sirolimus and 1.8 months (95 % CI [1.3–2.8]) for patients receiving multi-targeted tyrosine kinase inhibitors; 6-month PFS 15 %. The median Overall Survival (OS) was 6.8 months (95 % CI [4.7–12.1]), and one-year OS was 24 %. In a multivariate analysis, PFS was superior for patients receiving sirolimus compared to other TTs (Hazard Ratio (HR) = 2.7, 95 % CI [1.05–7.1]). No toxic death was reported. Grade 3 and 4 toxicities were observed in 27 and 6 % of cases respectively.

Conclusion

Off-label TTs, especially sirolimus, reported benefit in the treatment of refractory osteosarcomas with an acceptable toxicity profile, including in pediatric population.