Phase II study of temozolomide and thalidomide in patients with metastatic melanoma in the brain: high rate of thromboembolic events (CALGB 500102)

VEGF/VEGFR axis and its signaling in melanoma: Current knowledge toward therapeutic targeting agents and future perspectives

Melanoma is responsible for most skin cancer-associated deaths globally. The progression of melanoma is influenced by a number of pathogenic processes. Understanding the VEGF/VEGFR axis, which includes VEGF-A, PlGF, VEGF-B, VEGF-C, and VEGF-D and their receptors, VEGFR-1, VEGFR-2, and VEGFR-3, is of great importance in melanoma due to its crucial role in angiogenesis. This axis generates multifactorial and complex cellular signaling, engaging the MAPK/ERK, PI3K/AKT, PKC, PLC-γ, and FAK signaling pathways. Melanoma cell growth and proliferation, migration and metastasis, survival, and acquired resistance to therapy are influenced by this axis. The VEGF/VEGFR axis was extensively examined for their potential as diagnostic/prognostic biomarkers in melanoma patients and results showed that VEGF overexpression can be associated with unfavorable prognosis, higher level of tumor invasion and poor response to therapy. MicroRNAs linking to the VEGF/VEGFR axis were identified and, in this review, divided into two categories according to their functions, some of them promote melanoma angiogenesis (promotive group) and some restrict melanoma angiogenesis (protective group). In addition, the approach of treating melanoma by targeting the VEGF/VEGFR axis has garnered significant interest among researchers. These agents can be divided into two main groups: anti-VEGF and VEGFR inhibitors. These therapeutic options may be a prominent step along with the modern targeting and immune therapies for better coverage of pathological processes leading to melanoma progression and therapy resistance.

Developments in therapy for brain metastases in melanoma patients

Introduction: Cutaneous melanoma brain metastases (MBM) are a major cause of morbidity and mortality. While cytotoxic agents, interferon, or interleukin-2, have been used with some success in extracranial disease, limited efficacy is demonstrated in MBM. The rare patient with long-term survival presented with limited intracranial disease amenable to surgery or radiation therapy. However, the development of targeted therapy and immunotherapy over the last decade has significantly improved overall survival in this formerly devastating presentation of metastatic melanoma.Areas covered: This article reviews the mechanism of brain metastasis, challenges with treating the central nervous system, historical treatment of MBM, and outcomes in clinical trials with targeted therapy and immunotherapy.Expert opinion: The MBM patient population now, more than ever, requires a multidisciplinary approach with surgery, radiation therapy, and the use of newer systemic therapies such as immunotherapy agents and targeted therapy agents. MBM has traditionally been excluded from clinical trials for systemic therapy due to poor survival. However, recent data show overall survival rates have significantly improved, supporting the need for inclusion of MBM patients in systemic therapy clinical trials. Understanding the mechanisms of therapeutic activity in the brain, resistance  mechanisms, and the appropriate multi-modality treatment approach requires further investigation. Nevertheless, these therapies continue to give some hope to patients with historically poor survival.

A phase I trial of concurrent sorafenib and stereotactic radiosurgery for patients with brain metastases

We hypothesized that sorafenib (BAY 43-9006), an oral multi-kinase inhibitor, used in combination with SRS will improve overall intracranial control. This Phase I study assesses the safety, tolerability, and maximal tolerated dose of sorafenib administered with SRS to treat 1-4 brain metastases. This was an open label phase I dose escalation study with an expansion cohort. Eligible adults had 1-4 brain metastases from solid malignancies. Sorafenib was begun 5-7 days prior to SRS and continued for 14 days thereafter. Dose escalation of sorafenib was conducted via a "3 + 3" dose escalation design. Dose limiting toxicities (DLT) were determined 1 month after SRS and defined as ≥grade 3 neurologic toxicities. Twenty-three patients were enrolled. There were no DLTs at dose level 1 (400 mg per day) or dose level 2 (400 mg twice per day). An expansion cohort of 17 patients was treated at dose level 2. There were six grade 3 toxicities: hypertension (n = 2), rash (n = 1), lymphopenia (n = 1), hypokalemia (n = 1), fatigue (n = 1) and hand-foot syndrome (n = 1). All of these were attributable to sorafenib and not to the combination with SRS. The median time to CNS progression was 10 months, 1 year CNS progression-free survival was 46%, the median overall survival was 11.6 months and the 1 year overall survival was 46%. The use of sorafenib concurrent with SRS for the treatment of 1-4 brain metastases is safe and well tolerated at 400 mg twice a day. Our recommended phase II dose of concurrent sorafenib with SRS would be 400 mg twice daily.

Treatment of Brain Metastases

Brain metastases (BMs) occur in 10% to 20% of adult patients with cancer, and with increased surveillance and improved systemic control, the incidence is likely to grow. Despite multimodal treatment, prognosis remains poor. Current evidence supports use of whole-brain radiation therapy when patients present with multiple BMs. However, its associated cognitive impairment is a major deterrent in patients likely to live longer than 6 months. In patients with oligometastases (one to three metastases) and even some with multiple lesions less than 3 to 4 cm, especially if the primary tumor is considered radiotherapy resistant, stereotactic radiosurgery is recommended; if the BMs are greater than 4 cm, surgical resection with or without postoperative whole-brain radiation therapy should be considered. There is increasing evidence that systemic therapy, including targeted therapy and immunotherapy, is effective against BM and may be an early choice, especially in patients with sensitive primary tumors. In patients with progressive systemic disease, limited treatment options, and poor performance status, best supportive care may be appropriate. Regardless of treatment goals, use of corticosteroids or antiepileptic medications is helpful in symptomatic patients. In this review, we provide a summary of current therapy, as well as developments in the treatment of BM from solid tumors.

Management of melanoma brain metastases

Relapses in the brain remain a major obstacle to cure in many patients with advanced melanoma. At present, the management of melanoma brain metastases continues to rely heavily on surgical and radiotherapeutic interventions, which have become safer and more effective with modern imaging, surgery and radiation technologies. Additionally, novel targeted and immunotherapeutic agents, shown to generate meaningful intracranial response and survival benefit in patients with melanoma brain metastases when compared with historical controls, expand systemic treatment options for this subset of patients. These systemic therapies become particularly important when intracranial disease burden precludes neuro- or radio-surgery. Considerable multidisciplinary research effort is ongoing to improve outcomes for melanoma patients with brain metastases, a key challenge in the management of advanced melanoma.

Central nervous system cancers

Primary and metastatic tumors of the central nervous system are a heterogeneous group of neoplasms with varied outcomes and management strategies. Recently, improved survival observed in 2 randomized clinical trials established combined chemotherapy and radiation as the new standard for treating patients with pure or mixed anaplastic oligodendroglioma harboring the 1p/19q codeletion. For metastatic disease, increasing evidence supports the efficacy of stereotactic radiosurgery in treating patients with multiple metastatic lesions but low overall tumor volume. These guidelines provide recommendations on the diagnosis and management of this group of diseases based on clinical evidence and panel consensus. This version includes expert advice on the management of low-grade infiltrative astrocytomas, oligodendrogliomas, anaplastic gliomas, glioblastomas, medulloblastomas, supratentorial primitive neuroectodermal tumors, and brain metastases. The full online version, available at NCCN. org, contains recommendations on additional subtypes.

Combining temozolomide with other antitumor drugs and target-based agents in the treatment of brain metastases: an unending quest or chasing a chimera?

INTRODUCTION

Medical treatment of brain metastases (BM) is still a controversial issue in cancer therapy being mainly limited by the existence of the BBB. Temozolomide (TMZ) can cross BBB and several clinical trials have been performed attempting to demonstrate the activity of TMZ in combination with whole brain radiotherapy (WBRT) in the treatment of BM.

AREAS COVERED

This review summarizes TMZ-WBRT combination trials highlighting the confounding factors that limit the interpretation of the achieved results and describes the main clinical trials using TMZ in combination with other cytotoxic or biological agents. The main limitations of these trials are: i) patient selection for heterogenous primitive neoplasms and for heterogeneous neuro-functional score; ii) poor penetration across BBB of the other drugs; iii) cumulative toxicity and iv) poor control of extracranial tumor sites.

EXPERT OPINION

Biotechnological, biological and biochemical advances in the management of BM could allow in short time the definition of new schedules based on the rational use of new anticancer weapons. The latter could be cytotoxic agents encapsulated in nanotechnological tools able to cross BBB, lipophilic small kinase inhibitors (lapatinib, sunitinib), mTOR inhibitors and PARP inhibitors combined with old drugs such as TMZ.

Riluzole enhances ionizing radiation-induced cytotoxicity in human melanoma cells that ectopically express metabotropic glutamate receptor 1 in vitro and in vivo

PURPOSE

Brain metastases are a common preterminal event in patients with metastatic melanoma and require radiation therapy. Our group has previously shown that human GRM1 (hGRM1) expressing melanoma cells release excess extracellular glutamate and are growth inhibited by riluzole, an inhibitor of glutamate release. Riluzole-treated cells accumulate in G(2)/M phase of the cell cycle at 24 hours, and then undergo apoptotic cell death. We evaluated whether riluzole enhanced radiosensitivity in melanoma cells.

EXPERIMENTAL DESIGN

Clonogenic assays were performed to evaluate clonogenic survival after treatment in hGRM1 expressing and nonexpressing melanoma cells. Western immunoblots were performed to confirm apoptotic cell death. A xenograft mouse model was used to validate the in vitro experiments. Tumors harvested from the xenografts were fixed and stained for apoptosis and DNA damage markers.

RESULTS

In the hGRM1-positive cell lines C8161 and UACC903, riluzole enhanced the lethal effects of ionizing radiation; no difference was seen in the hGRM1-negative UACC930 cell line. C8161 cells treated with riluzole plus irradiation also showed the highest levels of the cleaved forms of PARP and caspase-3; excised C8161 xenografts showed the greatest number of apoptotic cells by immunohistochemistry (P < 0.001). On cell cycle analysis, a sequence-dependent enrichment in the G(2)/M phase was shown with the combination of riluzole and irradiation. Xenografts treated with riluzole and weekly radiation fractions showed significant growth inhibition and revealed markedly increased DNA damage.

CONCLUSIONS

We have shown, in vitro and in vivo, that the combination of riluzole and ionizing radiation leads to greater cytotoxicity. These results have clinical implications for patients with brain metastases receiving whole brain radiation therapy.

Prognostic factors for survival in melanoma patients with brain metastases

BACKGROUND

One of the most common and deadly complications of melanoma is brain metastases. The outcomes of advanced melanoma patients who developed brain metastases were reviewed to identify significant prognostic factors for overall survival (OS).

METHODS

An institutional database of advanced melanoma patients enrolled on clinical trials in the Department of Melanoma Medical Oncology from 1986 to 2004 was reviewed and patients who developed brain metastases were identified. Date of diagnosis, patient age, pattern of brain involvement, timing relative to extracranial metastases, prior response to systemic therapy, and treatments given for brain metastases were assessed as potential prognostic factors for OS.

RESULTS

Among 743 melanoma patients enrolled in clinical trials for regional or systemic metastatic disease, 330 (44%) patients developed brain metastases. The median OS after the diagnosis of brain metastases was 4.7 months. Diagnosis before 1996, increased number of parenchymal brain metastases, leptomeningeal involvement, and development of brain metastases after receiving systemic therapy for extracranial metastases were found to be significant prognostic factors for OS. Among patients who received systemic therapy as the initial treatment of brain metastases, patients who previously responded to systemic therapies had longer survival than patients who had not responded.

CONCLUSIONS

The era, pattern, and timing of melanoma brain metastases were found to be strongly associated with survival. Previous responsiveness to systemic therapies did not predict better outcomes overall, but it did correlate with improved survival for patients with brain metastases who were treated with systemic therapies. These factors may be used in guiding patient management and for stratifying patients in clinical trials.

Emerging risk stratification approaches to cancer-associated thrombosis: risk factors, biomarkers and a risk score

Cancer patients are well-known to be at increased risk of venous thromboembolism (VTE). However, the risk varies widely between patients and over the natural history of malignancy. Recent data have identified multiple clinical risk factors as well as biomarkers predictive of VTE. Risk factors include patient-associated factors such as age, obesity and medical comorbidities, cancer-associated factors such as site and stage of cancer, and treatment-associated factors, particularly chemotherapy and anti-angiogenic therapy. Biomarkers associated with increased risk of cancer-associated VTE include leukocyte count, platelet count, and levels of tissue factor, P-selectin and D-dimer. This review focuses on the evidence for risk stratification of cancer patients, based on these risk factors and biomarkers, as well as a recently validated predictive model which can be used to identify patients at highest risk. Targeted thromboprophylaxis utilizing model-based and/or biomarker-based approaches may provide an optimal risk-benefit ratio and is currently the focus of ongoing clinical trials.

The role of emerging and investigational therapies for metastatic brain tumors: a systematic review and evidence-based clinical practice guideline of selected topics

QUESTION

What evidence is available regarding the emerging and investigational therapies for the treatment of metastatic brain tumors?

TARGET POPULATION

These recommendations apply to adults with brain metastases.

RECOMMENDATIONS

New radiation sensitizers Level 2 A subgroup analysis of a large prospective randomized controlled trial (RCT) suggested a prolongation of time to neurological progression with the early use of motexafin-gadolinium (MGd). Nonetheless this was not borne out in the overall study population and therefore an unequivocal recommendation to use the currently available radiation sensitizers, motexafin-gadolinium and efaproxiral (RSR 13) cannot be provided. Interstitial modalities There is no evidence to support the routine use of new or existing interstitial radiation, interstitial chemotherapy and or other interstitial modalities outside of approved clinical trials. New chemotherapeutic agents Level 2 Treatment of melanoma brain metastases with whole brain radiation therapy and temozolomide is reasonable based on one class II study. Level 3 Depending on individual circumstances there may be patients who benefit from the use of temozolomide or fotemustine in the therapy of their brain metastases. Molecular targeted agents Level 3 The use of epidermal growth factor receptor inhibitors may be of use in the management of brain metastases from non-small cell lung carcinoma.

Assessing risk of venous thromboembolism in the patient with cancer

PURPOSE

Patients with cancer are increasingly at risk for venous thromboembolism (VTE). Rates of VTE, however, vary markedly among patients with cancer.

DESIGN

This review focuses on recent data derived from population-based, hospital-based, and outpatient cohort studies of patients with cancer that have identified multiple clinical risk factors as well as candidate laboratory biomarkers predictive of VTE.

RESULTS

Clinical risk factors for cancer-associated VTE include primary tumor site, stage, initial period after diagnosis, presence and number of comorbidities, and treatment modalities including systemic chemotherapy, antiangiogenic therapy, and hospitalization. Candidate predictive biomarkers include elevated platelet or leukocyte counts, tissue factor, soluble P-selectin, and D-dimer. A recently validated risk model, incorporating some of these factors, can help differentiate patients at high or low risk for developing VTE while receiving chemotherapy.

CONCLUSION

Identifying patients with cancer who are most at risk for VTE is essential to better target thromboprophylaxis, with the eventual goal of reducing the burden as well as the consequences of VTE for patients with cancer.

Diagnosis and treatment of melanoma brain metastasis: a literature review

BACKGROUND

Brain metastasis is common in patients with malignant melanoma and represents a significant cause of morbidity and mortality. Nearly 37% of patients with malignant melanoma eventually develop brain metastasis, and autopsy reports show that 75% of those who died of this disease developed brain metastasis.

METHODS

We review the level I and level II evidence that guides indications for treatment with surgery, stereotactic radiosurgery, chemotherapy, and immunotherapy for patients with melanoma brain metastasis.

RESULTS

Level I evidence supports the role of whole brain radiotherapy, microsurgery, and radiosurgery alone or in combination for the treatment of patients with melanoma brain metastasis. Chemotherapy has been ineffective. Ongoing studies continue to assess the effects of immunotherapy and agents in development.

CONCLUSIONS

Brain metastasis is a common and formidable challenge in patients with malignant melanoma. Although there have been no randomized controlled trials exclusively in patients with melanoma brain metastasis, care can be guided by the application of level I evidence for the treatment of brain metastasis in general and phase II studies focusing specifically on melanoma brain metastasis. Promising new agents and approaches are needed and will hopefully be identified in the near future.

Tumor angiogenesis in melanoma

A large number of clinical studies are being conducted to assess the effects of angiogenesis inhibitors in the treatment of patients who have metastatic melanoma. It has become increasingly clear that a therapeutic approach that combines angiogenesis inhibitors with cytotoxic agents or other treatment modalities is more likely to result in a clinical benefit for patients rather than antiangiogenesis treatments alone. However, a targeted treatment approach with antiangiogenic agents needs to be based on an in-depth understanding of the complex mechanisms involved in melanoma tumor angiogenesis.

Molecular-targeted therapy in malignant melanoma

Malignant melanoma is a deadly disease in which standard treatment options have remained remarkably static over the past 30 years. Recent discoveries have expanded the understanding of the molecular processes critical to melanomagenesis. During this same time period, therapeutic agents have been developed that target these processes, leading to an explosion of preclinical research. Several agents that have shown promise in the preclinical setting have now entered clinical trials. To date, the success of these molecularly targeted approaches as single agents has been limited. Although more encouraging results have been seen when these agents have been used in combination with cytotoxic therapy, the specific contribution of the targeted agents to the observed anti-tumor effects remains to be established in randomized controlled Phase III trials. This article presents a review of the limitations of current therapy, a description of key pathogenic mechanisms for which inhibitors exist and a summary of therapeutic trials of molecularly targeted agents in this disease.

A phase 1 study of granulocyte macrophage colony-stimulating factor (sargramostim) and escalating doses of thalidomide in patients with high-risk malignant melanoma

This phase 1 study evaluated the safety and tolerability of adjuvant treatment with subcutaneous granulocyte macrophage colony-stimulating factor (GM-CSF) administered in combination with escalating doses of thalidomide in patients with surgically resected stage II (T4), III, or IV melanoma at high risk for recurrence. Adjuvant treatment included GM-CSF 125 microg/m2 subcutaneously for 14 days and thalidomide at an initial dose of 50 mg/d, escalated in cohorts of 3 to 6 patients each to a maximum of 400 mg/d followed by 14 days of rest. Treatment was continued for up to 1 year in the absence of disease progression. Of 19 patients treated, the most common toxicities were grade 1/2 constipation (68%), fatigue (58%), neuropathy (42%), bone and joint pain (37%), and dyspnea, dizziness, injection site skin reaction, and somnolence (32% each). Thrombotic events in 3 of 19 patients (16%), including 1 treatment-related death, were the most serious adverse events and were thought to be due to thalidomide. With a median follow-up of 945 days (2.6 y), 8 (42%) patients were alive, including 1 with disease and 7 without evidence of disease. GM-CSF plus thalidomide as adjuvant therapy for patients with resected high-risk melanoma was associated with a high incidence of thrombotic events. Because life-threatening events are unacceptable in the adjuvant setting, up-front antithrombotic prophylaxis will be necessary for further evaluation of GM-CSF plus thalidomide as a viable regimen in this patient group.

Brain metastases: current management and new developments

PURPOSE OF REVIEW

To review the state-of-the-art and new developments in the management of patients with brain metastases.

RECENT FINDINGS

Treatment decisions are based on prognostic factors to maximize neurologic function and survival, while avoiding unnecessary therapies. Whole-brain radiotherapy (WBRT) is the treatment of choice for patients with unfavorable prognostic factors. Stereotactic radiosurgery (SRS) or surgery is indicated for patients with favorable prognostic factors and limited brain disease. In single brain metastasis, the addition of either stereotactic radiosurgery or surgery to WBRT improves survival. The omission of WBRT after surgery or radiosurgery results in a worse local and distant control, though it does not affect survival. The incidence of neurocognitive deficits in long-term survivors after WBRT remains to be defined. New approaches to avoid cognitive deficits following WBRT are being investigated. The role of chemotherapy is limited. Molecularly targeted therapies are increasingly employed. Prophylaxis with WBRT is the standard in small-cell lung cancer.

SUMMARY

Many questions need future trials: the usefulness of new radiosensitizers; the role of local treatments after surgery; and the impact of molecularly targeted therapies on subgroups of patients with specific molecular profiles. Quality of life and cognitive functions are recognized as major endpoints in clinical trials.

Therapeutic strategies for targeting mononuclear phagocytes in cancer

The initiation and progression of cancer is dependent on factors both intrinsic and extrinsic to the malignant cells. Stromal, vascular endothelial, and inflammatory cells are the principal normal populations that support tumors by supplying factors and nutrients. The mononuclear phagocyte lineage, which includes monocytes, macrophages, and dendritic cells is of particular clinical interest because lineage members can enhance tumor angiogenesis and metastasis, or alternately contribute to tumor destruction. Thus therapies that regulate these cells represent an innovative approach for improving patient survival in childhood cancer.

Temozolomide, thalidomide, and whole brain radiation therapy for patients with brain metastasis from metastatic melanoma: a phase II Cytokine Working Group study

BACKGROUND

The combination of temozolomide (TMZ) and thalidomide was reported to produce a high response rate, including shrinkage of brain metastases, in patients with metastatic melanoma. The authors tested the efficacy of a regimen including TMZ, thalidomide, and whole brain radiation therapy (WBRT) in patients with brain (CNS) metastases from melanoma.

METHODS

Patients with melanoma, CNS metastases documented by magnetic resonance imaging, and no prior systemic chemotherapy received WBRT, 30 Gray in 10 fractions, Days 1 to 5 and 8 to 12; TMZ, 75 mg/m(2)/day, Weeks 1 to 6; and thalidomide, 100 mg/day, Weeks 1 to 4, then escalated by 100 mg/day at Weeks 5, 7, and 9 as tolerated to a maximum of 400 mg/day. CNS and systemic tumor response was assessed at Week 10. Patients without CNS or clinically significant systemic disease progression received additional cycles of TMZ at 10-week intervals.

RESULTS

Thirty-nine patients received treatment, and 3 exhibited CNS response (1 complete response, 2 partial responses) (response rate, 7.6%; 95% confidence interval, 0.7%-16.1%), all unconfirmed by repeat imaging. Seven patients had stable CNS disease at 10 weeks. No patient exhibited a systemic response. Only 4 patients received 2 cycles of therapy, and just 1 received 3. Median time to progression was 7 weeks, and median overall survival was 4 months. Grade 3-4 side effects included deep venous thrombosis (3), pulmonary embolism (1), and CNS events (12). Eighteen (45%) patients required admission for side effects (7) and/or symptomatic disease progression (11).

CONCLUSIONS

The efficacy of TMZ, thalidomide, and WBRT in the treatment of CNS metastatic melanoma is low. Other treatment approaches should be considered for this patient population.

A phase II study of thalidomide and irinotecan for treatment of glioblastoma multiforme

PURPOSE

Irinotecan is a cytotoxic agent with activity against gliomas. Thalidomide, an antiangiogenic agent, may play a role in the treatment of glioblastoma multiforme (GBM). To evaluate the combination of thalidomide and irinotecan, we conducted a phase II trial in adults with newly-diagnosed or recurrent GBM.

PATIENTS AND METHODS

Thalidomide was given at a dose of 100 mg/day, followed by dose escalation every 2 weeks by 100 mg/day to a target of 400 mg/day. Irinotecan was administered on day 1 of each 3 week cycle. Irinotecan dose was 700 mg/m(2) for patients taking enzyme-inducing anticonvulsants and 350 mg/m(2) for all others. The primary endpoint was tumor response, assessed by MRI. Secondary endpoints were toxicity, progression-free survival, and overall survival.

RESULTS

Twenty-six patients with a median age of 55 years were enrolled, with fourteen evaluable for the primary outcome, although all patients were included for secondary endpoints. One patient (7%) exhibited a partial response after twelve cycles, and eleven patients (79%) had stable disease. The intention to treat group with recurrent disease included 16 patients who had a 6-month PFS of 19% (95% CI: 4-46%) and with newly-diagnosed disease included 10 patients who had a 6-month PFS of 40% (95% CI: 12-74%). Gastrointestinal (GI) toxicity was mild, but six patients (23%) experienced a venous thromboembolic complication. Two patients had Grade 4 treatment-related serious adverse events that required hospitalization. There were no treatment-related deaths.

CONCLUSION

The combination of irinotecan and thalidomide has limited activity against GBM. Mild GI toxicity was observed, but venous thromboembolic complications were common.

Genetic associations with thalidomide mediated venous thrombotic events in myeloma identified using targeted genotyping

A venous thromboembolism (VTE) with the subsequent risk of pulmonary embolism is a major concern in the treatment of patients with multiple myeloma with thalidomide. The susceptibility to developing a VTE in response to thalidomide therapy is likely to be influenced by both genetic and environmental factors. To test genetic variation associated with treatment related VTE in patient peripheral blood DNA, we used a custom-built molecular inversion probe (MIP)-based single nucleotide polymorphism (SNP) chip containing 3404 SNPs. SNPs on the chip were selected in "functional regions" within 964 genes spanning 67 molecular pathways thought to be involved in the pathogenesis, treatment response, and side effects associated with myeloma therapy. Patients and controls were taken from 3 large clinical trials: Medical Research Council (MRC) Myeloma IX, Hovon-50, and Eastern Cooperative Oncology Group (ECOG) EA100, which compared conventional treatments with thalidomide in patients with myeloma. Our analysis showed that the set of SNPs associated with thalidomide-related VTE were enriched in genes and pathways important in drug transport/metabolism, DNA repair, and cytokine balance. The effects of the SNPs associated with thalidomide-related VTE may be functional at the level of the tumor cell, the tumor-related microenvironment, and the endothelium. The clinical trials described in this paper have been registered as follows: MRC Myeloma IX: ISRCTN68454111; Hovon-50: NCT00028886; and ECOG EA100: NCT00033332.

A phase II study of thalidomide and temozolomide in patients with brain metastases from malignant melanoma: lymphopenia correlates with response

Background:

Central nervous system (CNS) metastases develop in nearly half of patients with advanced melanoma and in 15–20% CNS is the first site of relapse. Median overall survival is short, ranging from two to four months, and one-year survival rate is only 10–15%. THA has been shown to have both anti-angiogenetic and immuno-modulating effects. TMZ is an oral alkylating agent with an excellent oral bioavailability and it is highly lipophillic with an ability to penetrate the blood–brain barrier. TMZ and THA in combination were tested in patients with brain metastases from malignant melanoma.

Methods:

Between June 2004 and February 2007 patients with measurable metastatic melanoma in progression and PS ≤ 1 received TMZ in a dose of 150 mg/m² qd for seven days, followed by seven days off therapy and THA in 200 mg qd, both orally administered. Concomitant treatment with steroids was allowed. PBMCs were collected from the last 14 consecutive patients for evaluation of immune parameters.

Results:

Forty screened patients were eligible and evaluable for response, and 39 were evaluable for toxicity. 25 patients had asymptomatic and 15 symptomatic brain metastases. The toxicity was primarily grade 1–2 with no grade 4 or treatment-related deaths. Four patients had thromboembolic events grade 3. One patient obtained a CR and five a PR in the CNS, while two had CR and four had PR outside CNS. Overall response rate was 17.5%. We found a significant positive correlation between lymphopenia and objective response.

Conclusions:

The combination treatment was well tolerated but with more frequent thromboembolic events compared to single drug TMZ or THA. The treatment demonstrated activity in CNS as well as outside CNS. The correlation between lymphopenia and objective response needs further investigation.

Translational research in melanoma

Current treatment of malignant melanoma exemplifies not only the need for translational research but also many of the challenges of moving from bench to bedside. Melanoma remains unique among solid tumors in that its treatment primarily is surgical. Radiation is of limited benefit, and chemotherapy has been disappointing in both the adjuvant and metastatic settings. This leaves clinicians with few options for reducing the chance of recurrence after surgery and for treating unresectable disease. With this in mind, there has been a fervent attempt to identify novel approaches to melanoma therapy and translate them into clinical use.

[Experimental treatment of malignant melanoma and its rationale]

To treat malignant melanoma successfully currently means to recognize the tumor at an early stage and to remove it immediately. Aside from individual cases, available treatment modalities are not able to increase survival, especially in the palliative situation. Thus innovative experimental approaches are urgently needed to strongly improve the palliative and adjuvant treatment of melanoma. Anti-tumor effects are expected from targeted therapies, which are directed against defined molecules decisive for tumor pathogenesis. Crucial points of attack are signaling pathways, angiogenesis and apoptosis resistance. New diagnostic and therapeutic developments have enhanced the efficacy of chemotherapies. Increasing insights into tumor immunology provide new treatment approaches of vaccination, cell transfer and especially of blocking immune tolerance mechanisms. It will be challenging for the future to identify and characterize more precisely those patients who might most benefit from a certain treatment approach.

[Thromboembolic risk associated with use of angiogenesis inhibitors used for the treatment of cancers]

Among antiangiogenic agents, thalidomide is not the most potent nor the most specific even so when venous thromboembolic events have been reported with the prescription of thalidomide in multiple myeloma. This side effect has been related to the antiangiogenic effect of this immunomodulator. In keeping with this observation venous thromboembolic events have been reported in other indications of thalidomide and with thalidomide analogues (Lenalidomide and Actimid). The thrombotic side effects are mostly venous but arterial thrombotic events are also observed with the use of these molecules. With the other and more specific antiagiogenic agents an increase in thrombotic events are also observed. This increase was not immediately evident since the situation in which they are prescribed (metastatic cancers) are already characterized by a high rate of thrombotic events. The prothrombotic effect of antiangiogenic agents are probably linked to an effect on endothelium (decrease of antithrombotic activities and stimulation of a prothrombotuic state). The other sides effects of antiangiogenic agents (hemorrhages, hypertension, proteinuria, microangiotpahia, delay in scaring) are also probably related to endothelial effects. The prothrombotic effect of antoangiogenic agents appears as potentiating the prothrombotic conditions of the disease (myeloma, cancer) and the prothombotic effects of the associated treatments (chemotherapy, high dose corticosteroids, erythropoietin). The increased thrombotic risk linked to prescription of antiangiogenic agents and specially of thalidomide and analogues for multiple myeloma is such that it is recommended to associate a preventive antithrombotic treatment. Some efficacy has been reported with the use of aspirin, oral anticoagulant or low molecular weight heparin. No head to head comparative trial do not allow to prefer one strategy. From published data full dose oral anticoagulants appear to confer the highest hemorrhagic risk and perhaps low molecular weight heparin the best benefit-risk ratio.

Treatment of melanoma and nonmelanoma skin cancer

The incidence of skin cancer is increasing in Caucasian populations worldwide. Treatment approaches for Nonmelanoma skin cancer (NMSC) are predominantly curative and surgery can be regarded as standard of care. Nevertheless, novel and less invasive topical therapy modalities like photodynamic therapy or local immune modifiers are in progress. In contrast to NMSC, the mortality of melanoma has not changed considerably over the last years and decades. Melanoma survival mainly depends on primary tumor thickness underlining the importance of primary and secondary prevention by avoidance or early detection of the disease. The chance to cure melanoma patients is steadily decreasing with tumor stage. As the prognosis in distant metastatic disease is still poor, except for single situations therapy approaches are palliative and accompanied by an optimal supportive care of the patients concerned. Albeit removal of localized metastases is currently the most effective approach in metastatic melanoma, chemo- and chemoimmunotherapy has to be regarded as standard treatment in most of the cases. Novel and promising therapeutic options accrue from growing insights in tumor biology and immunology. Not only in melanoma, development and application of targeted therapies currently attract the most attention in the treatment of advanced tumors. First clinical experiences with those antiproliferative, antiangiogenic and proapoptotic agents reveal only moderate antitumoral activity in melanoma, so that future efforts aim at defining more effective combination strategies using chemo-, targeted and vaccination therapy approaches.

Evaluation of interferon alpha-2B and thalidomide in patients with disseminated malignant melanoma, phase 2, SWOG 0026

BACKGROUND

Southwest Oncology Group protocol 0026 evaluated interferon alpha-2b plus thalidomide in patients with disseminated melanoma. Endpoints were 6-month progression-free survival rate, response rate, and toxicity.

METHODS

Twenty-six patients with Stage IV melanoma, measurable or nonmeasurable disease, performance status of 0-2, and adequate renal and hepatic functions were registered. One prior systemic therapy for Stage IV disease was required. Interferon was administered subcutaneously (1 million U) twice daily; thalidomide was orally administered (200-400 mg) each evening in a dose-escalating manner. Response evaluations using Response Evaluation Criteria in Solid Tumors were performed every 8 weeks.

RESULTS

After 2 sudden deaths and 1 grade 4 treatment-related pulmonary embolism, this study was temporarily closed. One patient with deep-vein thrombosis and 2 with grade 3 cardiac arrhythmias were reported. The relationship of these events to the treatment was worrisome but not definitive. Grade 3 treatment-related adverse events occurred in 14 of 26 patients. Because of concern for patient safety the study was permanently closed. No treatment responses were seen in the 22 evaluable patients. Estimated 6-month progression-free survival rate was 15% (95% confidence interval [CI], 2%-29%), estimated 6-month overall survival was 58% (95% CI, 39%-77%), and estimated response probability was 0 of 22 (95% CI, 0%-15%).

CONCLUSIONS

This regimen demonstrated a lack of response and was associated with multiple severe toxicities. Further investigation of interferon alpha-2b and thalidomide in this dose and schedule is not warranted.

Phase II trial of pegylated interferon and thalidomide in malignant metastatic melanoma

Pegylated interferon and thalidomide demonstrate immunomodulatory and antiangiogenic activity, and efficacy in melanoma. The combination was evaluated in a phase II trial. Eligibility included biopsy-confirmed malignant melanoma with metastases and progression, maximum of two earlier systemic therapies, performance status of 0-2, and adequate hepatic, bone marrow and renal function. Pegylated interferon was administered at a dose of 0.5 microg/kg subcutaneously weekly and thalidomide 200 mg orally daily. Toxicity was evaluated every 2 weeks and response every 8 weeks. Eighteen patients were enrolled in this trial. Median age was 55.5 years (range: 29-80 years). Seventeen patients had visceral metastases and one had lymph node-only metastases. Two patients had brain metastases. Nine patients had received earlier adjuvant therapy and 16 patients had received earlier therapy for metastatic disease. Performance status was 0, 1 and 2 in 11, six and one patients, respectively. Severe (grade 4) toxicities observed were anemia in two patients and thrombocytopenia in one patient. No treatment-related deaths occurred. Dose escalation of thalidomide to 300 mg daily was feasible in four patients. One therapy-related hospitalization for nausea and dehydration occurred. No objective responses were noted; three patients demonstrated disease stabilization. The regimen of pegylated interferon and thalidomide was well tolerated. The combination, however, failed to demonstrate clinical efficacy in pretreated metastatic malignant melanoma.

New approaches in metastatic melanoma: biological and molecular targeted therapies

Classical metastatic melanoma therapy is disappointing but important progress has been made in the understanding of melanoma biology. Genetic lesions and several intracellular signaling pathways that could serve as targets for novel therapy have been identified and a number of new agents are under evaluation. Promising tumor cell targets were identified in the cell membrane, cytoplasm and nucleus. New therapeutic approaches, besides monoclonal antibodies and vaccination, include an increasing number of small molecules that have been shown to interfere restrictively with intracellular signaling pathways in melanoma and decrease proliferation, survival, migration or invasion. Other agents can interfere with stromal components of melanoma, such as angiogenesis and components of the immune system.

Current topics in melanoma

PURPOSE OF REVIEW

New approaches to melanoma are emerging. This review summarizes developments over the past 12 months.

RECENT FINDINGS

Surgical, chemotherapeutic, immunologic and targeted therapies for melanoma are evolving. Sentinel lymph node sampling is now accepted as the standard of care for patients with intermediate thickness primary melanomas. Temozolomide continues to be widely used as part of combination therapy, and recent evidence suggests that a combination of temozolomide and interferon-alpha may be superior to temozolomide alone. Meanwhile, temozolomide and thalidomide carries unacceptable thrombosis risk. In the area of immunotherapy, anti-CTLA-4 continues to show promise, but special attention must be paid to gastrointestinal toxicity. Interferon-alpha, in addition, has shown efficacy in the neoadjuvant setting with inflammatory infiltrates demonstrated in tumors. A better understanding of the complex genetic regulation of melanoma cell growth is emerging and this is expected to lead to the development of novel targeted therapies.

SUMMARY

Research is producing a more complete understanding of melanoma genetics and immune regulation. These are beginning to produce therapeutics that are impacting clinical practice.