Serum vascular endothelial growth factor as a tumour marker in soft tissue sarcoma

The vascular landscape of human cancer

Tumors depend on a blood supply to deliver oxygen and nutrients, making tumor vasculature an attractive anticancer target. However, only a fraction of patients with cancer benefit from angiogenesis inhibitors. Whether antiangiogenic therapy would be more effective if targeted to individuals with specific tumor characteristics is unknown. To better characterize the tumor vascular environment both within and between cancer types, we developed a standardized metric - the endothelial index (EI) - to estimate vascular density in over 10,000 human tumors, corresponding to 31 solid tumor types, from transcriptome data. We then used this index to compare hyper- and hypovascular tumors, enabling the classification of human tumors into 6 vascular microenvironment signatures (VMSs) based on the expression of a panel of 24 vascular "hub" genes. The EI and VMS correlated with known tumor vascular features and were independently associated with prognosis in certain cancer types. Retrospective testing of clinical trial data identified VMS2 classification as a powerful biomarker for response to bevacizumab. Thus, we believe our studies provide an unbiased picture of human tumor vasculature that may enable more precise deployment of antiangiogenesis therapy.

Neoadjuvant intravitreal ranibizumab treatment in high-risk ocular melanoma patients: a two-stage single-centre phase II single-arm study

Despite an established history of intraocular antivascular endothelial growth factor (anti-VEGF) agents therapy in a variety of ocular pathologies as well as other cancer forms, use in the primary treatment of uveal melanoma has not been well assessed. This was a two-stage therapeutic and exploratory phase II, non-randomised, single centre trial involving intraocular treatment with 0.5 mg in 0.05 ml of ranibizumab via six intravitreous injections over 6 months in patients with primary ocular melanoma that otherwise required radical surgery because of tumour size. Seven patients were recruited with a median age of 66 years. At baseline, the longest basal diameter was 15.1 mm (mean, range 10-20.4 mm) with a height measured by ultrasonography of 9.2 mm (mean, range 6.6-12.7 mm). No patients achieved complete or partial response at any visit. All required enucleation. Histopathological analysis revealed mixed cell melanoma in 5/7 (71%) and spindle cell morphology in 2/7 (29%) with ciliary body involvement in 4/7 (57%) and the presence of closed loops also in 4/7 (57%). Genetic analysis demonstrated loss of chromosome 3 in 5/7 (71%) but abnormalities in chromosome 1,6 or 8 in all cases. Our study was terminated early as alternative treatments were clearly superior for local tumour control. There continues to be a role of intravitreal anti-VEGF for the treatment of the sequelae of local radiotherapy in the form of radiation retinopathy and so these agents may be used as adjuncts in the treatment of uveal melanoma rather than as a primary treatment.

Real-World Experiences with Pazopanib in Patients with Advanced Soft Tissue and Bone Sarcoma in Northern California

Background: Pazopanib was approved for advanced soft tissue sarcoma as a second- or third-line therapy based on the clinical trial "Pazopanib for metastatic soft-tissue sarcoma" (PALETTE). We hypothesized that the real-world experiences may be significantly different from the clinical trial results. Methods: We analyzed the response pattern of patients with advanced soft tissue and bone sarcoma who received pazopanib treatment between 1 January 2011 and 31 October 2018 in Kaiser Permanente Northern California. Results: A total of 123 patients with 23 different histologic subtypes were assessable. One patient with low-grade fibromyxoid sarcoma obtained complete response (CR) after 2 months of treatment with pazopanib, 12 patients (9.7%) obtained partial response (PR), 34 patients (27.6%) had stable disease (SD), while 76 patients (61.8%) developed progressive disease (PD). The disease control rate (DCR) was 46.3% (CR + PR + SD). Among the 12 patients with PR, 3 had undifferentiated pleomorphic sarcoma (UPS), 4 had leiomyosarcoma (LMS), 2 had pleomorphic rhabdomyosarcoma, 1 had pleomorphic liposarcoma, 1 had dedifferentiated liposarcoma, and 1 had angiosarcoma. The median duration of response was 9 months. Two patients with Ewing's sarcoma had SD for 6 and 13 months, and two patients with osteosarcoma had SD for 6 and 9 months. Among 65 patients assessed at 8 weeks, 9 had a response, and 10 had SD. Among 104 patients assessed at 12 weeks, 12 had a response, and 26 had SD. The median progression-free survival (PFS) was approximately 3 months for all 123 cases and for patients with UPS and LMS. Conclusions: Our cohort of patients with advanced soft tissue and bone sarcoma in Northern California treated with pazopanib had diverse histologic subtypes. The response rate (CR + PR) was higher than that of the PALETTE trial, while the DCR and the median PFS were significantly lower. The observation of PR in two patients with liposarcoma and durable SD in several patients with bone sarcoma indicates that pazopanib has activity in liposarcoma and bone sarcoma.

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.

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.

Targeted therapy in sarcomas other than GIST tumors

Non-GIST soft tissue sarcomas are a heterogeneous grouping of mesenchymal tumors that comprise less than 1% of adult malignancies. Treatment continues to be based on cytotoxic chemotherapy regimens. However, characterization of the molecular pathway deregulations that drive these tumors has led to the emergence of more customized treatment options. In this review, we focus on the multitude of molecular inhibitors targeting angiogenesis and cell cycle pathways being tested in clinical trials.

Study protocol of REGOSARC trial: activity and safety of regorafenib in advanced soft tissue sarcoma: a multinational, randomized, placebo-controlled, phase II trial

Background

Angiogenesis, among other signaling pathways, plays a key-role in sarcoma biology. Regorafenib (RE) has recently been shown to be effective in imatinib and sunitinib-refractory GIST in a phase III trial.

Methods/design

We are conducting an international trial (France, Austria and Germany) consisting in 4 parallel double-blind placebo-controlled randomized (1/1) phase II trials to assess the activity and safety of RE in doxorubicin-refractory STS (ClinicalTrials.gov: NCT01900743). Each phase II trial is dedicated to one of the 4 following histological subgroups: liposarcoma, leiomyosarcoma, synovial sarcoma and other sarcoma. Within each randomized trial the following stratification factors will be applied: countries and prior exposure to pazopanib. Key-eligibility criteria are: measurable disease, age ≥18, not > 3 previous systemic treatment lines for metastatic disease, metastatic disease not amenable to surgical resection. The primary endpoint is progression-free survival (PFS) according to central radiological review. Secondary endpoints are: Toxicity (NCI-CTC AE V4.0); time to progression; Growth modulation index in pts receiving RE after randomization; 3 and 6 months PFS-Rates, best response rate and overall survival. Each phase II trial will be separately analyzed. In 3 trials, statistical assumptions are: PFS0 = 1.6 & PFS1 = 4.6 months; 1-sided α = 0.1; β = 0.05 with a total sample size of 192 pts. To take into account the rarity of synovial sarcoma, the statistical assumptions are: PFS0 = 1.6 & PFS1 = 4.6 months; 1-sided α = 0.1; β = 0.2 Tumor assessment is done monthly during the 4 first months, and every 3 months thereafter. After central radiological confirmation of tumor progression, an optional open-label option is offered to eligible patients.

Discussion

The design of this trial allows an assessment of regorafenib activity over placebo in four sarcoma strata and might provide evidence for launching a phase III trial. This study includes both integrative and exploratory translational research program. The study is enrolling since June 2013 (Trial Registration Number: EudraCT N°: 2012-005743-24, on the 15^th February 2012).

The angiogenic asset of soft tissue sarcomas: a new tool to discover new therapeutic targets

STS (soft tissue sarcomas) are rare malignant tumours deriving from cells of mesenchymal origin and represent only 1% of all malignant neoplasms. It has been extensively demonstrated that angiogenesis has an important role in cancer malignancy. Particularly, a lot of studies demonstrate the importance of angiogenesis in the development of carcinomas, whereas little is known about the role of angiogenesis in sarcomas and especially in STS. This review aims at summarizing the new discoveries about the nature and the importance of angiogenesis in STS and the new possible therapeutic strategies involved. Only a few studies concerning STS focus on tumour neovascularization and proangiogenic factors and look for a correlation with the patients prognosis/survival. These studies demonstrate that intratumoural MVD (microvessels density) may not accurately represent the angiogenic capacity of STS. Nevertheless, this does not exclude the possibility that angiogenesis could be important in STS. The importance of neoangiogenesis in soft tissue tumours is confirmed by the arising number of publications comparing angiogenesis mediators with clinical features of patients with STS. The efficacy of anti-angiogenic therapies in other types of cancer is well documented. The understanding of the involvement of the angiogenic process in STS, together with the necessity to improve the therapy for this often mortal condition, prompted the exploration of anti-tumour compounds targeting this pathway. In conclusion, this review emphasizes the importance to better understand the mechanisms of angiogenesis in STS in order to subsequently design-specific target therapies for this group of poorly responding tumours.

A phase Ib/II translational study of sunitinib with neoadjuvant radiotherapy in soft-tissue sarcoma

Background:

Preoperative radiotherapy (RT) is commonly used to treat localised soft-tissue sarcomas (STS). Hypoxia is an important determinant of radioresistance. Whether antiangiogenic therapy can ‘normalise' tumour vasculature, thereby improving oxygenation, remains unknown.

Methods:

Two cohorts were prospectively enrolled. Cohort A evaluated the implications of hypoxia in STS, using the hypoxic tracer ¹⁸F-azomycin arabinoside (FAZA-PET). In cohort B, sunitinib was added to preoperative RT in a dose-finding phase 1b/2 design.

Results:

In cohort A, 13 out of 23 tumours were hypoxic (FAZA-PET), correlating with metabolic activity (r²=0.85; P<0.001). Two-year progression-free (PFS) and overall (OS) survival were 61% (95% CI: 0.44–0.84) and 87% (95% CI: 0.74–1.00), respectively. Hypoxia was associated with radioresistance (P=0.012), higher local recurrence (Hazard ratio (HR): 10.2; P=0.02), PFS (HR: 8.4; P=0.02), and OS (HR: 41.4; P<0.04). In Cohort B, seven patients received sunitinib at dose level (DL): 0 (50 mg per day for 2 weeks before RT; 25 mg per day during RT) and two patients received DL: −1 (37.5 mg per day for entire period). Dose-limiting toxicities were observed in 4 out of 7 patients at DL 0 and 2 out of 2 patients at DL −1, resulting in premature study closure. Although there was no difference in PFS or OS, patients receiving sunitinib had higher local failure (HR: 8.1; P=0.004).

Conclusion:

In STS, hypoxia is associated with adverse outcomes. The combination of sunitinib with preoperative RT resulted in unacceptable toxicities, and higher local relapse rates.

Anti-angiogenic therapy, a new player in the field of sarcoma treatment

Sarcomas encompass a heterogeneous family of mesenchymal malignancies. In metastatic disease improvement in outcome has been limited and there is a clear need for the development of new therapies. One potential target is angiogenesis, already an accepted target for treatment of more prevalent cancers. Multiple (pre)clinical studies focused on the role of angiogenesis and anti-angiogenic treatment in sarcomas. However, getting significant results is complicated due to the relatively small number of patients and the broad range of sarcoma subtypes. Recently, pazopanib has been approved for the treatment of advanced soft tissue sarcoma patients, which is an important step forward and paves the way for the introduction of anti-angiogenic treatment in sarcomas. However, more studies are needed to understand the biological mechanisms by which patients respond to angiogenic inhibitors and to detect markers of response. This review covers the knowledge that has been gained on the role of angiogenesis and anti-angiogenic therapy in sarcomas.

The VEGF- and PDGF-family of angiogenic markers have prognostic impact in soft tissue sarcomas arising in the extremities and trunk

Background

Soft-tissue sarcomas are rare malignant tumors of mesenchymal lineage that can arise in any part of the body. Prognosis, and hence also treatment may vary according to histologic subtype and localization. Angiogenesis is the process of forming new blood vessels from pre-existing ones. The deregulation of this process is thought to be an important step in malignant transformation. This study investigates the prognostic impact of platelet derived growth factor- (PDGF), vascular endothelial growth factor- (VEGF) and fibroblast growth factor (FGF) families in soft-tissue sarcomas of the extremities & trunk (ET) and visceral & retroperitoneal (VR) locations.

Methods

Tumor samples from 181 patients (115 ET and 66 VR) with resected soft tissue sarcomas were collected and tissue microarrays were constructed. Immunohistochemistry was used to evaluate angiogenic marker expression. Recurrence-free survival (RFS), metastasis-free survival (MFS) and disease-specific survival (DSS) were used as endpoints in prognostic impact assessment.

Results

In univariate analyses, almost all investigated angiogenic markers had prognostic impact in the ET group. In contrast, only FGFR-1 showed any significant prognostic impact in the VR group. In the multivariate analyses, PDGF-D (HR = 1.863, 95% CI = 1.057-3.283, P = 0.031), VEGFR-1 (HR = 2.106, 95% CI = 1.038-4.272, P = 0.039) and VEGF-A (HR 2.095, 95% CI 1.028-4.271, P = 0.042) were independent negative prognosticators for DSS, MFS and RFS, respectively, in the ET group. FGFR-1 was an independent positive prognosticator for DSS (HR = 0.243, 95% CI = 0.095-0.618, P = 0.003) in the VR group.

Conclusions

Angiogenic molecules from the PDGF and VEGF families have prognostic impact in soft-tissue sarcomas arising in the ET, but not in VR locations. In the latter histological grade and resection margins are the most important prognostic factors.

Pazopanib is an active treatment in desmoid tumour/aggressive fibromatosis

Background

Desmoid tumours/aggressive fibromatosis (DT/AF) are infrequent soft-tissue neoplasms. They usually behave as indolent diseases. However, they may grow locally infiltrating or compressing adjacent structures. The role of local treatment is limited and only a few drugs have shown activity.

Cases presentation

We report the outcome of two patients affected by progressive DT/AF treated with the angiogenesis inhibitor pazopanib in two different institutions. Both patients achieved dramatic improvement in their symptoms and radiological signs of response. The clinical benefit lasted for more than 1 year and it is still ongoing.

Conclusions

Pazopanib is an active treatment in DT/AF. It is the first time this has been reported.

The evolution of systemic therapy in sarcoma

Approximately 50% of patients with localized soft tissue sarcomas will develop recurrent disease after complete surgical resection, requiring alternative means of treatment. Conventional chemotherapy comprising of doxorubicin and ifosfamide has shown benefit in advanced disease, however, there remains a clear need for more effective, less toxic, therapies for the treatment of this heterogeneous group of mesenchymal malignancies. Recently, greater emphasis has been placed on the underlying biology of individual sarcoma subtypes, with the development and evaluation of novel therapies both in common and in rare subtypes. In addition, there is a greater specificity in the selection of chemotherapy agents based on activity in individual histological subtypes. Despite these advances the management of sarcoma, and in particular of rare subtypes, remains a major challenge. Some histological subtypes are resistant to conventional chemotherapy and patients with these diseases should be offered participation in early phase clinical trials of novel drugs.

Targeted treatment for advanced soft tissue sarcoma: profile of pazopanib

Soft tissue sarcomas comprise approximately 1% of all adult solid malignancies. While chemotherapy is the mainstay of treatment for patients with metastatic or inoperable disease, overall survival for these patients is approximately 12 months, highlighting the need for novel agents. Both laboratory and clinical data have suggested that antiangiogenic agents may have a role in the treatment of soft tissue sarcomas. Pazopanib is a multitargeted receptor tyrosine kinase inhibitor with antiangiogenic activity. The randomized, double-blind, placebo-controlled, Phase III PALETTE (pazopanib for metastatic soft-tissue sarcoma) study demonstrated improved progression-free survival in patients receiving pazopanib compared with placebo. In this review, we discuss the rationale and clinical evidence for the use of pazopanib in the treatment of metastatic and inoperable soft tissue sarcomas.

Pazopanib, a new therapy for metastatic soft tissue sarcoma

INTRODUCTION

Pazopanib (GW786034, Votrient®) is a vascular endothelial growth factor receptor-focused multi-tyrosine kinase inhibitor involved in inhibiting the angiogenesis pathway. The agent was recently registered for use in soft tissue sarcomas, a group of diseases with a major unmet medical need.

AREAS COVERED

The relevance of angiogenesis in soft tissue sarcomas is discussed. These data were the basis to decide on the development of pazopanib in these diseases. The clinical pharmacology of pazopanib, as far as practically relevant, is summarized. After the first observations of possible activity in soft tissue sarcomas in the Phase I study, a Phase II and subsequent randomized placebo-controlled Phase III study were performed and are being put into perspective in this review.

EXPERT OPINION

Pazopanib is an active drug for the treatment of chemotherapy-failing nonadipocytic soft tissue sarcomas. It almost triples progression-free survival significantly from 1.6 to 4.6 months in this heavily pretreated population. The safety profile is manageable, exemplified by the high dose intensity that can be achieved over time. Pazopanib can be considered as part of the standard of care for patients with soft tissue sarcomas.

Pazopanib in the treatment of soft tissue sarcoma

Patients with advanced metastatic soft tissue sarcoma (STS) have a poor prognosis, and in the last two decades of the 20th century their overall survival has remained unchanged. Improved treatments are needed for these patients and for preventing metastases in earlier stages of disease. Numerous novel agents and new combination regimens are undergoing clinical testing in STS. Some of these agents show promising activity. Pazopanib is one such agent that has undergone Phase II and III evaluations in advanced STS. Pazopanib is a multi-tyrosine kinase inhibitor, blocking various signaling pathways, thereby preventing angiogenesis and metastasis, and inhibiting tumor cell growth and survival. In a Phase II study, pazopanib demonstrated activity in patients with advanced leiomyosarcomas, synovial sarcomas and other eligible STSs. This activity was confirmed in a Phase III trial, where pazopanib significantly extended the median progression-free survival versus placebo in a variety of STS subtypes.

Vascular endothelial growth factor serum levels in children with newly diagnosed rhabdomyosarcoma

BACKGROUND

The adverse prognostic impact of elevated levels of circulating Vascular Endothelial Growth Factor (VEGF) is described in several malignancies. However, no information is available in childhood rhabdomyosarcoma (RMS). In the present study, serum VEGF-A (sVEGF-A) was measured at diagnosis in a series of patients with RMS.

PROCEDURE

sVEGF-A was assessed retrospectively in 17 newly diagnosed RMS patients. sVEGF-A concentrations were determined by quantitative enzyme-linked immunoabsorbent ELISA kit and their possible associations with age at diagnosis, gender, histology, primary site, primary size, Intergroup Rhabdomyosarcoma Study (IRS) post-surgical group, and outcome were investigated.

RESULTS

sVEGF-A median value in patients with RMS was significantly higher than in controls: 499.0 pg/ml, range: 2,648.0 versus 301.5 pg/ml, range: 716.0 (P = 0.013). Although not statistically significant probably due to the limited number of patients, sVEGF-A median levels resulted higher in unfavorable primary sites (277.0 vs. 539.0 pg/ml; P = 0.31), and advanced groups (390.0 vs. 715.0; P = 0.29). Patients with shorter 5-year overall survival (OS) and 5-year progression-free survival (PFS) times also had higher sVEGF-A levels, although again the difference was not statistically significant (P = 0.18 and P = 0.22, respectively).

CONCLUSIONS

Circulating VEGF is significantly increased in pediatric patients with newly diagnosed RMS. Further studies in larger series of RMS patients are needed to understand whether measurements of circulating VEGF might have a role in assessing prognosis and modulating treatment.

Pazopanib: a promising new agent in the treatment of soft tissue sarcomas

Pazopanib (GW786034) is a novel, small-molecule tyrosine kinase inhibitor. The primary mechanism of action of pazopanib can be described through its antiangiogenic properties via inhibition of the intracellular tyrosine kinase of VEGF receptor (VEGFR) and PDGF receptor (PDGFR). It is an orally available angiogenesis inhibitor that targets VEGFR-1, -2 and -3, PDGFR-α and -β, and c-kit. Pazopanib exhibits distinct pharmacokinetic and toxicity profiles compared with other agents in that class. Phase I studies defined the recommended monotherapy dose of pazopanib as 800 mg once daily. In 2009, it was approved in the USA for the treatment of advanced and metastatic renal cell carcinoma, and subsequently approved in other countries and demonstrated clinically and statistically significant activity in Phase II and III studies in advanced soft tissue sarcoma patients. This article focuses on its emerging role in the treatment of advanced soft tissue sarcomas.

Phase IB study of the combination of docetaxel, gemcitabine, and bevacizumab in patients with advanced or recurrent soft tissue sarcoma: the Axtell regimen

BACKGROUND

To assess the response of patients with soft tissue sarcoma (STS) to the combination of docetaxel, bevacizumab, and gemcitabine. Vascular endothelial growth factor (VEGF)-A levels and expression of VEGF-A and VEGF receptors 1 and 2 were evaluated.

PATIENTS AND METHODS

Thirty-eight chemotherapy-naive patients with STS were enrolled. A dose-finding study for gemcitabine from 1000, 1250, then 1500 mg/m(2) was done in nine patients (three cohorts), followed by an expansion cohort of 27 patients. Dose of docetaxel was 50 mg/m(2), bevacizumab was 5 mg/kg, and gemcitabine was 1500 mg/m(2), every 2 weeks. Serum VEGF-A was measured by enzyme-linked immunosorbent assay and tissue VEGF-A and its receptors by immunohistochemistry.

RESULTS

The median follow-up was 36 months. The overall response rate observed was 31.4%, with 5 complete and 6 partial responses, and 18 stable diseases lasting for a median of 6 months. There was no significant hematologic toxicity. The adverse events with the highest grade were attributed to bevacizumab. There was no correlation of VEGF pathway biomarkers with outcome.

CONCLUSIONS

The combination of gemcitabine, docetaxel, and bevacizumab is safe and effective in patients with STS. The most concerning adverse events were consequences of bevacizumab administration. The benefit of bevacizumab in this patient population remains unclear.

Serum vascular endothelial growth factor in dogs with soft tissue sarcomas

This work aimed to evaluate serum vascular endothelial growth factor (VEGF) in 25 dogs with soft tissue sarcoma, and in 30 healthy dogs. Blood was collected once time from the control animals and three times, in the same way, from animals with sarcoma. Blood count was performed in the blood collected, and serum VEGF was measured by enzyme-linked immunosorbent assay quantitative method. Serum VEGF in control animals was similar to patients with soft tissue sarcoma. There was a reduction in serum VEGF after the sarcoma resection. There was positive correlation between serum VEGF and neutrophil counts, and negative between VEGF and hemoglobin content in animals with sarcoma. Animals with hemangiopericytoma showed higher serum VEGF levels compared to the patients with malignant peripheral nerve sheath. Circulating blood cells can contribute to elevate VEGF serum concentrations in dogs with soft tissue sarcomas and a possible role of VEGF in the angiogenesis of these tumors.

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

Soft tissue sarcomas (STS) represent a diverse group of histologic subtypes with targetable molecular alterations, often treated as a single disease. Sunitinib malate is a multitargeted receptor tyrosine kinase inhibitor active in other solid tumors carrying similar alterations (i.e., imatinib mesylate-refractory gastrointestinal stromal tumors). This single-institution phase II study investigated the safety and efficacy of sunitinib malate in three common STS subtypes. Patients with documented unresectable or metastatic STS (liposarcoma, leiomyosarcoma and malignant fibrous histiocytoma [MFH]), measurable disease, and 3 or less prior lines of therapy were eligible. Treatment consisted of sunitinib malate, 50 mg daily, for 4 weeks every 6 weeks. Forty-eight patients were enrolled, and 35% were heavily pretreated (≥ 2 prior lines of chemotherapy). The safety profile resembled previously known sunitinib malate toxicities. Median progression-free and overall survivals for liposarcoma, leiomyosarcoma, and MFH were 3.9 and 18.6, 4.2 and 10.1 and 2.5 and 13.6 months, respectively. The 3-month progression-free rates in the untreated and pretreated (chemotherapy) patients with liposarcoma, leiomyosarcoma and MFH were 75% and 69.2%, 60%, and 62.5% and 25% and 44.4%, respectively. With the caveats that a minority of patients with potentially indolent or low-grade disease could have been included and the small numbers, a 3-month progression-free rate of >40% suggests activity for sunitinib malate at least in liposarcomas and leiomyosarcomas. Thus, we believe that further investigation in these susceptible STS subtypes is warranted.

Profiling of VEGFs and VEGFRs as prognostic factors in soft tissue sarcoma: VEGFR-3 is an independent predictor of poor prognosis

BACKGROUND

In non-gastrointestinal stromal tumor soft tissue sarcoma (non-GIST STS) optimal treatment is surgery with wide resection margins. Vascular endothelial growth factors (VEGFs) and receptors (VEGFRs) are known to be key players in the initiation of angiogenesis and lymphangiogenesis. This study investigates the prognostic impact of VEGFs and VEGFRs in non-GIST STS with wide and non-wide resection margins.

METHODS

Tumor samples from 249 patients with non-GIST STS were obtained and tissue microarrays were constructed for each specimen. Immunohistochemistry was used to evaluate the expressions of VEGF-A, -C and -D and VEGFR-1, -2 and -3.

RESULTS

In the univariate analyses, VEGF-A (P=0.040) in the total material, and VEGF-A (P=0.018), VEGF-C (P=0.025) and VEGFR-3 (P=0.027) in the subgroup with wide resection margins, were significant negative prognostic indicators of disease-specific survival (DSS). In the multivariate analysis, high expression of VEGFR-3 (P=0.042, HR=1.907, 95% CI 1.024-3.549) was an independent significant negative prognostic marker for DSS among patients with wide resection margins.

CONCLUSION

VEGFR-3 is a strong and independent negative prognostic marker for non-GIST STSs with wide resection margins.

Pazopanib: an antiangiogenic drug in perspective

Pazopanib, a tyrosine kinase inhibitor targeted to angiogenesis, has been tested in preclinical and clinical trials and has shown promising activity against a variety of solid tumors, such as renal cancer, all of which are related to the angiogenic pathway. It has a safety profile related to this mechanism of action. Diarrhea, hypertension, hair depigmentation and nausea are the most common side effects. Pazopanib is currently under evaluation as monotherapy and in combination with some potentially synergistic agents of proven activity.

Pazopanib, a multikinase angiogenesis inhibitor, in patients with relapsed or refractory advanced soft tissue sarcoma: a phase II study from the European organisation for research and treatment of cancer-soft tissue and bone sarcoma group (EORTC study 62043)

PURPOSE Given the importance of angiogenesis in soft tissue sarcoma (STS), pazopanib, an oral angiogenesis inhibitor that targets vascular endothelial growth factor receptor and platelet-derived growth factor receptor, was explored in patients with advanced STS. PATIENTS AND METHODS Patients with intermediate- or high-grade advanced STS who were ineligible for chemotherapy or who had received no more than two prior cytotoxic agents for advanced disease, who had documented progression, who had adequate performance status, and who had good organ function were eligible. Pazopanib 800 mg was given daily. The primary end point was progression-free rate at 12 weeks (PFR(12 weeks)). Secondary end points were response, safety, and overall survival. Four different strata were studied: adipocytic STS, leiomyosarcomas, synovial sarcomas, and other STS types. A Simon two-stage design was applied (P1 = 40%; P0 = 20%; alpha = beta = .1) for each stratum. Results One hundred forty-two patients were enrolled. The adipocytic STS stratum was closed after the first stage, given insufficient activity (PFR(12 weeks), five [26%] of19). PFR(12 weeks) was 18 (44%) of 41 patients in the leiomyosarcoma cohort, 18 (49%) of 37 in the synovial sarcomas, and 16 (39%) of 41 in the other STS types. Compared with historical controls who were treated with second-line chemotherapy, progression-free and overall survivals were prolonged in the three cohorts in which the primary end point was reached. The most frequent drug-related toxicities were hypertension, fatigue, hypopigmentation, and nausea. Other toxicities included liver enzyme elevations, myelosuppression, and proteinuria, all of which were mostly grades 1 to 2. The most frequent grades 3 to 4 toxicities were hyperbilirubinemia (6.3%), hypertension (7.7%), and fatigue (7.7%). CONCLUSION Pazopanib is well tolerated in patients with relapsed, advanced STS and demonstrates interesting activity that warrants additional study in patients with leiomyosarcomas, synovial sarcomas, and other STS types.

Molecularly targeted therapy and cancer surgery

May reduce micrometastases

Markers of angiogenesis and clinical features in patients with sarcoma

The growth and dissemination of sarcomas depends on angiogenesis. A number of measurable markers related to tumor angiogenesis have been studied in patients with sarcoma. The available literature related to markers of angiogenesis and clinical features in patients with sarcoma was reviewed. Clinical features of interest included tumor size, tumor grade, tumor stage, presence of metastatic disease, and prognosis. In patients with soft-tissue sarcomas, tumor vascular endothelial growth factor (VEGF) expression correlates with stage, grade, and prognosis. Circulating VEGF levels also correlate with tumor grade. High circulating angiopoietin-2 levels are associated with increased tumor size in soft-tissue sarcoma. For patients with osteosarcoma, tumor VEGF expression correlates with outcome. Elevated tumor and circulating VEGF levels are associated with the development of lung metastases in osteosarcoma. Patients with Ewing sarcoma have increased circulating VEGF levels compared with controls. Angiogenesis markers correlate with important clinical features in patients with sarcomas ranging from soft-tissue sarcomas to bone sarcomas. Markers of angiogenesis may serve an important role in predicting a particular patient's clinical course and in identifying patients for possible antiangiogenic therapy. Cancer 2007 (c) 2006 American Cancer Society.

Giant cell tumor of the uterus: case report and response to chemotherapy

Background

Giant cell tumor (GCT) is usually a benign but locally aggressive primary bone neoplasm in which monocytic macrophage/osteoclast precursor cells and multinucleated osteoclast-like giant cells infiltrate the tumor. The etiology of GCT is unknown, however the tumor cells of GCT have been reported to produce chemoattractants that can attract osteoclasts and osteoclast precursors. Rarely, GCT can originate at extraosseous sites. More rarely, GCT may exhibit a much more aggressive phenotype. The role of chemotherapy in metastatic GCT is not well defined.

Case presentation

We report a case of an aggressive GCT of the uterus with rapidly growing lung metastases, and its response to chemotherapy with pegylated-liposomal doxorubicin, ifosfamide, and bevacizumab, along with a review of the literature.

Conclusion

Aggressive metastasizing GCT may arise in the uterus, and may respond to combination chemotherapy.

Primary pulmonary artery sarcoma: report of three cases and review of the literature

Pulmonary artery sarcomas (PASs) are rare tumors of the vasculature of the lung that usually present as a thromboembolism. Failure of anticoagulant therapy to relieve all of a patient's symptoms suggests the diagnosis. Approximately 75% of patients with PAS present with dyspnea, and slightly > 50% also experience chest pain or cough. Imaging studies (chest computed tomography with 3-dimensional reconstruction, magnetic resonance imaging, perfusion lung scan, and pulmonary angiogram) are usually unspecific. A definitive diagnosis requires pathologic examination of tissue obtained by intravascular, percutaneous, or surgical biopsy. Treatment of primary PAS is usually surgical with or without adjuvant chemotherapy or radiation therapy. Because these tumors are rare, data from large randomized trials are not available. Palliative chemotherapy with anthracyclines and ifosfamide is the usual treatment in advanced disease, with response rates of approximately 50%. The mean survival time ranges from 14 months to 18 months. We report 3 cases of PAS treated with surgery and chemotherapy (anthracyclines and ifosfamide) with different outcomes.

Circulating CA125 in patients with peritoneal mesothelioma treated with cytoreductive surgery and intraperitoneal hyperthermic perfusion

BACKGROUND

Recent phase I/II trials report encouraging results in selected patients with peritoneal mesothelioma (PM) treated with cytoreductive surgery (CRS) and intraperitoneal hyperthermic perfusion (IPHP). Circulating tumor markers have never been extensively investigated in the management of PM. We assessed the clinical role of markers in a large series of patients with PM undergoing CRS and IPHP.

METHODS

Clinical data on 60 patients with PM operated with the intention to perform adequate CRS (residual tumor nodules <or= 2.5mm) and IPHP were prospectively collected. Marker levels were determined pre-operatively, post-operatively, and routinely during long-term follow-up. Baseline diagnostic sensitivity, accuracy in monitoring response to treatment or tumor progression and prognostic significance were determined.

RESULTS

Baseline diagnostic sensitivity was 53.3% for CA125, 0 for CEA, 3.8% for CA19.9 and 48.5% for CA15.3. Forty-six patients underwent adequate cytoreduction and IPHP; gross residual tumor was left after the operation in fourteen. Postoperatively, CA125 became negative in 21/22 patients with elevated baseline levels undergoing adequate CRS and IPHP, while remained elevated in 9/9 patients with persistent macroscopic disease. CA125 became positive in 12/12 patients with elevated baseline levels developing disease progression after adequate CRS and IPHP. Baseline CA125 showed borderline prognostic significance only among patients not previously treated with systemic chemotherapy.

CONCLUSIONS

CA125 was elevated in the majority of patients with PM in the present series. Serial maker measurements paralleled tumor growth or regression after CRS and IPHP, suggesting the need of further studies to assess the role of CA125 in this clinical setting.

Microvessel density does not predict outcome in high grade soft tissue sarcoma

The induction of new blood vessel growth into tumours from a pre-existing vascular bed (angiogenesis) is a characteristic of virtually all malignant tumours studied. Previous studies have demonstrated a consistent correlation between the extent of angiogenesis and disease prognosis for a wide range of carcinomas, but not for sarcomas.

AIMS

To investigate the most appropriate method for assessment of microvessel density (MVD) using a cohort of patients with large (>5 cm), deep (intramuscular), high grade soft tissue sarcoma and investigate any relationship between MVD, vascular endothelial growth factor (VEGF) expression and prognosis.

METHODS

Forty-two patients were included in the study. MVD was evaluated in peripheral, central, necrotic and hotspot areas within the tumour by either Chalkley count or total count of immunostained vessels in five high power (x 200) visual fields.

RESULTS

Hot spots of angiogenesis were only present in 33% of specimens. There was a strong correlation p<0.001 between the two methods of quantification with Chalkey method being recommended. VEGF expression evaluated by immunohistochemistry was seen in all but one tumour with strong diffuse cytoplasmic staining within tumour cells, which was not correlated with microvessel density, metastasis or survival. There was a positive correlation between MVD and histological subtype (p<0.01), and primary tumour size and the development of metastasis (p=0.049) but MVD was not predictive of metastasis or overall survival.

CONCLUSIONS

Unlike the majority of previous studies involving various types of carcinoma, there was no correlation between microvessel density and metastasis or survival in a group of patients with large (>5 cm), deep, high grade soft tissue sarcoma.

Serum vascular endothelial growth factor as a significant marker of treatment response in pediatric malignancies

The aim of this pilot study was to determine VEGF serum levels (S-VEGF) at diagnosis and at restaging in children diagnosed with cancer, and to investigate whether this parameter provides prognostic information for remission after induction therapy and response to treatment. S-VEGF levels of 35 consecutive pediatric patients with various types of cancer were assayed at diagnosis and at restaging. Levels of VEGF were determined using a commercially available ELISA anti-human VEGF immunoassay kit. Thirty-one children went into complete remission or had a very good partial response to first-line therapy; 4 patients developed tumor progression. At diagnosis average S-VEGF level was 495 pg/mL (range, 0.89--2220 pg/mL) and at restaging it decreased to 118.36 pg/mL (range, 7.44--487 pg/mL). (p=.0039). The 4 patients with tumor progression had increased S-VEGF levels at restaging. The comparison between the levels of S-VEGF at diagnosis and at restaging showed a significant difference for the patients who responded to treatment with decreased S-VEGF and the patients who developed tumor progression with increased S-VEGF (p=.0019). One child with metastatic Ewing sarcoma developed progressive disease after several weeks, with significantly progressively higher S-VEGF levels. One child with Hodgkin disease, who had a higher level at first restaging and developed progressive disease, responded to reinduction therapy and had a significantly lower level at the second restaging. The child with metastatic hepatoblastoma responded to first-line chemotherapy with concomitant decrease in S-VEGF and alpha-fetoprotein levels, but developed local recurrence with elevation in both parameters. Changes in S-VEGF levels correlated with response to treatment for most of the children diagnosed with cancer. This provides a rationale for exploring clinical interest in S-VEGF measurements of a larger group of children with malignancies, and using the test for clinical trials of antiangiogenic therapies.