New Therapeutic strategies for soft tissue sarcomas

Evaluation for therapeutic measures to small gastric stromal tumor: A retrospective study of 90 cases

Surgery and regular follow-up are two main measures for small gastric stromal tumors (sGST) less than 2cm in diameter, while there is no sound evidence to prove which treatment is more beneficial to sGST patients. In this study, we reviewed the clinical and pathological features of patients with sGST receiving surgery and discussed the value of surgical intervention. In all, 90 patients who were diagnosed as sGST(less than 2cm) and accepted surgical treatment were enrolled, correspondently, another 104 patients with GSTs between 2-5cm and 74 patients with GSTs >5cm were collected as Control groups 1 and 2, respectively, and all of them received surgical treatment. Results showed that there were no significant difference among 3 groups in terms of gender, age, clinical features, tumor locations, and mutations of the exon 9 or 11 in C-kit gene, and immunohistochemical results of CD117, CD34, and DOG-1 proteins (P > 0.05). However, we observed growing percentage of medium-/high-risk GSTs and nucleus mitotic counts >5/50 HPF in Control groups (P < 0.05). Patients with sGST were more suitable for minimally invasive procedures than the other 2 groups, with shorter hospital stay (P < 0.05). During the follow-up period (medium 45.4 months), the recurrence rate was also associated with tumor size, which surged from 1.11% in sGST group to 7.69% and 17.56% in Control groups 1 and 2, respectively. In all, we concluded that patients with sGST experienced low proportions of medium-/high-risk tumors; however, they still suffered from potential risk of tumor progression. Due to satisfied surgical outcome, surgical treatment could be suggested for sGST.

Paclitaxel-Dependent Prolonged and Persistent Complete Remission Four Years from First Recurrence of Secondary Breast Angiosarcoma

Among angiosarcomas, radiation-induced breast sarcomas (RIBS) represent a well-known entity generally characterized by a poor outcome, especially in patients with advanced disease. Despite the unfavorable prognosis, some chemotherapeutic agents have been used to treat these malignancies, occasionally with success. Treatments with demonstrated activity against sarcomas include ifosfamide-based regimens and, more recently, taxane derivatives.

We report a case of a patient having a secondary breast angiosarcoma recurring early after surgery, who achieved complete remission following treatment with weekly paclitaxel. After 4 years of maintenance therapy, with an interval between consecutive administrations of no longer than 3 weeks, the patient is still in complete remission. A locoregional recurrence was documented twice during this period, the first as a consequence of a brief treatment interruption and the second because of a treatment delay. Nonetheless, in both instances a new complete remission was rapidly achieved with the resumption of the same treatment, without evidence of any significant adverse effects. We discuss the highly unusual behavior of this malignancy and the possible role of the two different mechanisms of action of paclitaxel-antiangiogenic versus cytotoxic-depending on the schedule of administration, with evidence of “false” drug-resistance.

Retrospective study of laparoscopic versus open gastric resection for gastric gastrointestinal stromal tumors based on the propensity score matching method

BACKGROUND

Surgical resection with a free margin is considered the gold standard for the treatment of gastric gastrointestinal stromal tumors (GISTs). Previous studies about the advantages of laparoscopic resection versus open surgery have generally been non-randomized and retrospective and have some obvious shortcomings that could influence the veracity and reliability of the results. Therefore, the aim of this study was to evaluate the efficacy of laparoscopic resection in the treatment of gastric GISTs using the propensity score matching (PSM) method.

METHODS

Between 2005 and 2014, 217 consecutive patients undergoing laparoscopic or open resection for gastric GISTs were enrolled in a retrospective, single-center study. Patient and tumor characteristics, intraoperative and postoperative characteristics, and oncologic outcomes were collected from a database. The efficacy of the laparoscopic approach was analyzed using the PSM method by comparing the clinical parameters of patients who underwent laparoscopic (LAP) and open resection (OPEN) procedures.

RESULTS

After PSM, 88 patients involved in the analysis (44 LAP vs. 44 OPEN) were randomly matched (1:1) by tumor size, localization, disease course, body mass index, age, and gender. The LAP group was clearly superior to the open group in terms of intraoperative indicators and postoperative short-term efficacy. The incidence of postoperative complications in the LAP group was lower than in the OPEN group (4.5 vs. 18.2 %, P = 0.044). A survival analysis showed that there was no significant difference in the disease-free survival time between the two groups (χ ² = 0.211, P = 0.646).

CONCLUSION

These data should be processed using the PSM method in a non-randomized controlled trial (non-RCT) study. It is safe and feasible for patients with gastric GISTs up to 5 cm in size or located in the gastroesophageal junction to be treated with laparoscopic surgery.

A case of tumor lysis syndrome following chemotherapy for a uterine epithelioid leiomyosarcoma with focal rhabdomyosarcomatous differentiation

Tumor lysis syndrome (TLS) is a potential complication characterized by hyperuricemia, hyperphosphatemia, hyperkalemia and hypocalcemia due to massive necrosis of malignant cells after cytotoxic therapy. This fatal complication occurs frequently in tumors with hematological malignancies, such as acute lymphoblastic leukemia and Burkitt's lymphoma, and in other tumors with high proliferative rates and tumor burdens. TLS is rarely associated with the treatment of solid tumors. Herein, we report a case of TLS following the initial administration of effective chemotherapy for an epithelioid leiomyosarcoma with focal rhabdomyosarcomatous differentiation of the uterus.

Rapamycin pharmacokinetic and pharmacodynamic relationships in osteosarcoma: a comparative oncology study in dogs

Background

Signaling through the mTOR pathway contributes to growth, progression and chemoresistance of several cancers. Accordingly, inhibitors have been developed as potentially valuable therapeutics. Their optimal development requires consideration of dose, regimen, biomarkers and a rationale for their use in combination with other agents. Using the infrastructure of the Comparative Oncology Trials Consortium many of these complex questions were asked within a relevant population of dogs with osteosarcoma to inform the development of mTOR inhibitors for future use in pediatric osteosarcoma patients.

Methodology/Principal Findings

This prospective dose escalation study of a parenteral formulation of rapamycin sought to define a safe, pharmacokinetically relevant, and pharmacodynamically active dose of rapamycin in dogs with appendicular osteosarcoma. Dogs entered into dose cohorts consisting of 3 dogs/cohort. Dogs underwent a pre-treatment tumor biopsy and collection of baseline PBMC. Dogs received a single intramuscular dose of rapamycin and underwent 48-hour whole blood pharmacokinetic sampling. Additionally, daily intramuscular doses of rapamycin were administered for 7 days with blood rapamycin trough levels collected on Day 8, 9 and 15. At Day 8 post-treatment collection of tumor and PBMC were obtained. No maximally tolerated dose of rapamycin was attained through escalation to the maximal planned dose of 0.08 mg/kg (2.5 mg/30kg dog). Pharmacokinetic analysis revealed a dose-dependent exposure. In all cohorts modulation of the mTOR pathway in tumor and PBMC (pS6RP/S6RP) was demonstrated. No change in pAKT/AKT was seen in tumor samples following rapamycin therapy.

Conclusions/Significance

Rapamycin may be safely administered to dogs and can yield therapeutic exposures. Modulation pS6RP/S6RP in tumor tissue and PBMCs was not dependent on dose. Results from this study confirm that the dog may be included in the translational development of rapamycin and potentially other mTOR inhibitors. Ongoing studies of rapamycin in dogs will define optimal schedules for their use in cancer and evaluate the role of rapamycin use in the setting of minimal residual disease.

Effect of type 1 insulin-like growth factor receptor targeted therapy on chemotherapy in human cancer and the mechanisms involved

INTRODUCTION

Chemotherapy is administered only to patients with advanced cancers, typically to modest avail. Hence, the search for innovative approaches to treat cancer is growing rapidly. One such approach involves targeting molecular pathways identified as encouraging tumor growth and maintenance, particularly the type 1 insulin-like growth factor (IGF-1) and its receptor (IGF-1R) pathway that is important in conferring chemoresistance.

MATERIALS AND METHODS

This study focuses on IGF-1R targeted therapy, which will enhance chemotherapy efficacy, through reviewing recent literature from PubMed and Medline databases.

CONCLUSION

This review examines data and strategies addressing an approach conquering chemoresistance through the combination of IGF-1R targeted therapy and chemotherapy in cancer patients, as well as the mechanisms by which IGF-1R acts as a target. This will impact on future research on treatment selection, thereby improving patient prognosis.

A novel tyrosine-kinase selective inhibitor, sunitinib, induces transient hypothyroidism by blocking iodine uptake

CONTEXT

Sunitinib (sunitinib malate; SU11248; Sutent; Pfizer Inc., New York, NY) is a multitarget inhibitor of tyrosine kinases for the treatment of some human cancers. A myxedematous coma in a patient treated with sunitinib for a gastrointestinal stromal tumor was unexpectedly observed.

OBJECTIVE

Our objective was to evaluate the effect of sunitinib on thyroid function in 24 patients with gastrointestinal stromal tumors.

DESIGN

This was a prospective, observational cohort study.

SETTING

The study was performed at two tertiary care hospitals.

PATIENTS

A total of 24 patients receiving the following cycles of therapy were included in the study: 4-wk daily treatment at the dose of 50 mg orally (ON) and 2-wk withdrawal (OFF).

INTERVENTIONS

Thyroid function tests, ultrasonography, and iodine-123 ((123)I) thyroidal uptake were performed at the end of several ON and OFF periods.

RESULTS

After one to six cycles of treatment, 46% of patients developed hypothyroidism. Initially, TSH levels were elevated at the end of ON periods and normalized at the end of OFF periods, but a worsening in following cycles was always observed. Neither echographic alterations nor variations in thyroglobulin and antithyroid autoantibodies were found during the ON and OFF periods. On the contrary, (123)I uptake was significantly reduced at the end of ON periods, with partial or total normalization at the end of OFF periods.

CONCLUSIONS

A high prevalence of hypothyroidism, very severe in some cases, was observed during sunitinib. Significant variations in (123)I uptake strongly suggest that the underlying mechanism is an impaired iodine uptake. The absence of thyroid autoimmunity, the lack of a preceding transient hyperthyroidism, and the normal echographic pattern exclude autoimmune and/or destructive mechanisms. Patients on sunitinib should be strictly monitored for the appearance of hypothyroidism and promptly treated.

A phase II and pharmacological study of the matrix metalloproteinase inhibitor (MMPI) COL-3 in patients with advanced soft tissue sarcomas

This phase II study evaluated the antitumor activity of the tetracycline analog COL-3, a potent inhibitor of metalloproteinases (MMPs), particularly MMP-2 and MMP-9, on a continuous oral schedule at a dose of 50 mg/m2 daily in patients with advanced and/or metastatic soft tissue sarcoma (STS). The principal endpoints were the rate of objective tumor regression and the proportion of patients who did not experience disease progression during the first 8 weeks of treatment. Other study objectives included an assessment of pharmacology of COL-3, time to progression (TTP), and overall survival. A Simon two-stage design with multinomial stopping rule was employed, with 15 patients enrolled during the first stage of the study. Although COL-3 was generally well-tolerated, there were no objective responses and 5(33%) patients experienced disease progression during the first 8 weeks of treatment, which exceeded the criteria established a priori with regard to pursuing further evaluations of COL-3 in STS. The median values for TTP and survival were 109 and 279 days, respectively. Based on these results, further studies of COL-3 on this administration schedule in patients with STS are not warranted.

Angiogenic Profile of Soft Tissue Sarcomas Based on Analysis of Circulating Factors and Microarray Gene Expression

BACKGROUND

Broader understanding of diverse angiogenic pathways in a particular cancer can lead to better utilization of anti-angiogenic therapies. The aim of this study was to develop profiles of angiogenesis-related gene and protein expression for various histologic subtypes of soft tissue sarcomas (STS) growing in different sites.

MATERIALS AND METHODS

Plasma levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiopoietin 2 (Ang2), and leptin were determined in 108 patients with primary STS. Gene expression patterns were analyzed in 38 STS samples and 13 normal tissues using oligonucleotide microarrays.

RESULTS

VEGF and bFGF plasma levels were elevated 10-13 fold in STS patients compared to controls. VEGF levels were broadly elevated while bFGF levels were higher in patients with fibrosarcomas and leiomyosarcomas. Ang2 levels correlated with tumor size and were most elevated for tumors located in the trunk, while leptin levels were highest in patients with liposarcomas. Hierarchical clustering of microarray data based on angiogenesis-related gene expression demonstrated that histologic subtypes of STS often shared similar expression patterns, and these patterns were distinctly different from those of normal tissues. Matrix metalloproteinase 2, platelet-derived growth factor receptor, alpha and Notch 4 were among several genes that were up-regulated at least 7-fold in STS.

CONCLUSIONS

STS demonstrate significant heterogeneity in their angiogenic profiles based on size, histologic subtype, and location of tumor growth, which may have implications for anti-angiogenic strategies. Comparison of STS to normal tissues reveals a panel of upregulated genes that may be targets for future therapies.