Pleura mesothelioma: combined modality treatments

PET-guided dose escalation tomotherapy in malignant pleural mesothelioma

PURPOSE

To test the feasibility of salvage radiotherapy using PET-guided helical tomotherapy in patients with progressive malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

A group of 12 consecutive MPM patients was treated with 56 Gy/25 fractions to the planning target volume (PTV); FDG-PET/CT simulation was always performed to include all positive lymph nodes and MPM infiltrations. Subsequently, a second group of 12 consecutive patients was treated with the same dose to the whole pleura adding a simultaneous integrated boost of 62.5 Gy to the FDG-PET/CT positive areas (BTV).

RESULTS

Good dosimetric results were obtained in both groups. No grade 3 (RTOG/EORTC) acute or late toxicities were reported in the first group, while 3 cases of grade 3 late pneumonitis were registered in the second group: the duration of symptoms was 2-10 weeks. Median overall survival was 8 months (1.2-50.5 months) and 20 months (4.3-33.8 months) from the beginning of radiotherapy, for groups I and II, respectively (p=0.19). A significant impact on local relapse from radiotherapy was seen (median time to local relapse: 8 vs 17 months; 1-year local relapse-free rate: 16% vs 81%, p=0.003).

CONCLUSIONS

The results of this pilot study support the planning of a phase III study of combined sequential chemoradiotherapy with dose escalation to BTV in patients not able to undergo resection.

Imaging and therapy of malignant pleural mesothelioma using replication-competent herpes simplex viruses

BACKGROUND

Malignant pleural mesothelioma (MPM) is an aggressive cancer that is refractory to current treatment modalities. Oncolytic herpes simplex viruses (HSV) used for gene therapy are genetically engineered, replication-competent viruses that selectively target tumor cells while sparing normal host tissue. The localized nature, the potential accessibility and the relative lack of distant metastasis make MPM a particularly suitable disease for oncolytic viral therapy.

METHODS

The infectivity, selective replication, vector spread and cytotoxic ability of three oncolytic HSV: G207, NV1020 and NV1066, were tested against eleven pathological types of MPM cell lines including those that are resistant to radiation therapy, gemcitabine or cisplatin. The therapeutic efficacy and the effect on survival of NV1066 were confirmed in a murine MPM model.

RESULTS

All three oncolytic HSV were highly effective against all the MPM cell lines tested. Even at very low concentrations of MOI 0.01 (MOI: multiplicity of viral infection, ratio of viral particles per cancer cell), HSV were highly effective against MPM cells that are resistant to radiation, gemcitabine and cisplatin. NV1066, an oncolytic HSV that expresses green fluorescent protein (GFP), was able to delineate the extent of the disease in a murine model of MPM due to selective infection and expression of GFP in tumor cells. Furthermore, NV1066 was able to reduce the tumor burden and prolong survival even when treatment was at an advanced stage of the disease.

CONCLUSION

These findings support the continued investigation of oncolytic HSV as potential therapy for patients with therapy-resistant MPM.

Exploiting the PI3K/AKT pathway for cancer drug discovery

Evolving studies with several different targeted therapeutic agents are demonstrating that patients with genomic alterations of the target, including amplification, translocation and mutation, are more likely to respond to the therapy. Recent studies indicate that numerous components of the phosphatidylinositol-3-kinase (PI3K)/AKT pathway are targeted by amplification, mutation and translocation more frequently than any other pathway in cancer patients, with resultant activation of the pathway. This warrants exploiting the PI3K/AKT pathway for cancer drug discovery.

Mitogenic Signal Transduction Pathways in Meningiomas: Novel Targets for Meningioma Chemotherapy?

The roles of growth factor receptors and numerous downstream growth regulatory pathways are of increasing interest in neuro-oncology. These pathways have been extensively studied in gliomas but only recently analyzed in meningiomas. This article reviews current research on the growth factor receptor-Ras-Raf-1-MEK-1-MAPK, PI3K-Akt/PKB, PLC-gamma1-PKC, phospholipase A2-cyclooxygenase, and TGF-beta receptor-Smad pathways that appear to regulate meningioma growth and inhibit apoptosis. Sites along these receptor/kinase cascades that might be targeted by novel therapies are also discussed.

Novel targeted agents in the treatment of lung cancer

Lung cancer is the leading cause of cancer-related mortality in the US. Although an improvement in outcome is possible with the continued advancement of cytotoxic-based treatment, clinical research is currently focused on utilising novel molecular targets with proven efficacy in preclinical models and a low toxicity profile. This is the result of advances in understanding of tumour biology and molecular pathways that have been implicated in cancer pathogenesis and progression. Novel agents targeting cell cycle regulation, angiogenesis and signal transduction pathways have reached clinical testing in lung cancer and are discussed in this review.

Accuracy of whole-body dual-modality fluorine-18-2-fluoro-2-deoxy-D-glucose positron emission tomography and computed tomography (FDG-PET/CT) for tumor staging in solid tumors: comparison with CT and PET

PURPOSE

To assess the accuracy of positron emission tomography/computed tomography (PET/CT) when staging different malignant diseases.

PATIENTS AND METHODS

This was a retrospective, blinded, investigator-initiated study of 260 patients with various oncological diseases who underwent fluorine-18-2-fluoro-2-deoxy-d-glucose PET/CT for tumor staging. CT images alone, PET images alone, PET + CT data viewed side by side, and fused PET/CT images were evaluated separately according to the tumor-node-metastasis system. One hundred forty patients with tumors not staged according to the tumor-node-metastasis system or a lack of reference standard were excluded from data analysis; 260 patients were included. Diagnostic accuracies were determined for each of the four image sets. Histopathology and a clinical follow-up of 311 (+/- 125) days served as standards of reference.

RESULTS

PET/CT proved significantly more accurate in assessing tumor-node-metastasis system stage compared with CT alone, PET alone, and side-by-side PET + CT (P < .0001). Of 260 patients, 218 (84%; 95% CI, 79% to 88%) were correctly staged with PET/CT, 197 (76%; 95% CI, 70% to 81%) with side-by-side PET + CT, 163 (63%; 95% CI, 57% to 69%) with CT alone, and 166 (64%; 95% CI, 58% to 70%) with PET alone. Combined PET/CT had an impact on the treatment plan in 16, 39, and 43 patients when compared with PET + CT, CT alone, and PET alone, respectively.

CONCLUSION

Tumor staging with PET/CT is significantly more accurate than CT alone, PET alone, and side-by-side PET + CT. This diagnostic advantage translates into treatment plan changes in a substantial number of patients.

Estrogen receptor pathways in lung cancer

Lung cancer is the leading cause of death from neoplasia in men and women in the United States. Some studies suggest that women are more susceptible than men to tobacco-induced carcinogenesis and may show higher risk than men for lung cancer development from smoking. More recently, increasing biochemical and genetic data have supported this male-female difference in response to tobacco. Estrogens may be involved in lung carcinogenesis, and estrogen receptors (ERs), mainly ERb, are present and functional in normal lung and tumor cell lines and tissues. Estrogen can directly stimulate the transcription of estrogen-responsive genes in the nucleus of lung cells, and it can also transactivate growth factor signaling pathways, in particular the epidermal growth factor pathway. Lung cancer patients currently have few effective therapeutic options. An understanding of these new developments in estrogen signaling and cross-talk pathways may pave the way for innovative combinatorial approaches for treatment of lung cancer and possibly chemoprevention.

Fatal pulmonary toxicity in a patient treated with gefitinib for non-small cell lung cancer after previous hemolytic-uremic syndrome due to gemcitabine

Gefitinib is a low-molecular-weight epidermal growth factor receptor tyrosine kinase inhibitor. To date, gefitinib has been administered to over 65,000 people worldwide. The most commonly reported adverse events were diarrhea, acne-like skin rash, nausea, vomiting and asthenia. Most of them were transient and mild in severity. Interstitial lung disease in patients who have been treated with gefitinib is uncommon and has recently been described with an estimated incidence rate of around 1%. We present here a case of fatal drug-induced pulmonary toxicity after therapy with gefitinib for metastatic non-small cell lung cancer. The patient had been treated with gemcitabine and cisplatin, and developed drug-induced hemolytic-uremic syndrome 6 months before gefitinib use.

The role of EGFR inhibitors in nonsmall cell lung cancer

PURPOSE OF REVIEW

The epidermal growth factor receptor is a cell membrane receptor that plays a key role in cancer development and progression. Ligand-activated epidermal growth factor receptor-dependent signaling is involved in cell proliferation, apoptosis, angiogenesis, invasion, and metastasis. Targeting the epidermal growth factor receptor represents a promising molecular approach in cancer treatment. Several antiepidermal growth factor receptor agents are in clinical development. This review focuses on the available clinical data on epidermal growth factor receptor-targeting drugs in the treatment of nonsmall cell lung cancer.

RECENT FINDINGS

Three drugs are currently in phase 2 and phase 3 development as single agents or in combination with other anticancer therapies in nonsmall cell lung cancer patients: cetuximab (Erbitux), a chimeric human-mouse monoclonal IgG1 antibody that blocks ligand binding and functional epidermal growth factor receptor activation; and erlotinib (Tarceva) and gefitinib (Iressa), two orally bioavailable, small-molecule epidermal growth factor receptor inhibitors of tyrosine kinase enzymatic activity that prevent epidermal growth factor receptor autophosphorylation and activation. Single-agent gefitinib treatment has determined a 10 to 20% response rate and a 30 to 50% symptom improvement in previously treated, chemotherapy-refractory advanced nonsmall cell lung cancer patients. Gefitinib has been the first epidermal growth factor receptor-targeting agent to be registered as an anticancer drug in several countries, including Japan, Australia, and the United States, for the third-line treatment of chemoresistant nonsmall cell lung cancer patients.

SUMMARY

Antiepidermal growth factor receptor has shown promising antitumor activity in nonsmall cell lung cancer patients with a mild toxicity profile. However, a series of important clinical issues such as selection of potentially responsive patients and optimal combination with conventional anticancer treatments needs to be addressed to use these drugs better in lung cancer.

Systemic treatment policies in ovarian cancer: the next 10 years

Over the past two decades, the development of treatment policies and practice standards has become formalized. In ovarian cancer, most attention has been focused on the development of policies for front-line systemic treatment, using survival as the major outcome that should drive change. This review summarizes the evidence that supported the emergence of paclitaxel-carboplatin as a widely used standard of care for front-line therapy and some of the contradictory data from randomized studies. Furthermore, recently completed or ongoing randomized studies of the addition of a third cytotoxic agent to paclitaxel-carboplatin are summarized. Finally, some novel noncytotoxic approaches are discussed. New standards of care and treatment policies in the next decade will be based on high-quality evidence of improved survival from controlled studies. Many such trials are now ongoing or planned.

Treatment of non-small-cell lung cancer: state of the art and development of new biologic agents

Conventional treatment of non-small-cell lung cancer (NSCLC) has apparently reached a plateau of effectiveness in improving the survival of NSCLC patients. Although neoadjuvant and adjuvant therapies in early stages are under investigation and some progress has been achieved in the management of locally advanced and advanced disease, treatment outcomes for NSCLC are still to be considered dismal. The majority of patients affected from NSCLC experience metastatic disease and optimization of chemotherapy is unlikely to produce further substantial survival improvement, with symptom relief and quality of life still being the primary goal of treatment. Based on this background, clinical investigation of novel treatment strategies is mandatory. As our understanding of tumor cell biology has increased and several molecular targets for NSCLC have been identified, a number of new biologic agents have been developed. Targeted therapy describes treatment strategies that focus on cell signaling and other biologic pathways involved in tumorigenesis. Several targeted agents have been introduced in clinical trials in NSCLC, the majority in advanced disease, and some phase III studies have already produced definitive results. Currently, the minority of these new agents offer promise of improved outcomes and negative results are more common to be reported than positive ones. However, important lessons can be learned from this first generation of clinical trials that should be considered the first step of clinical research in this field.

Chemotherapy in metastatic and locally advanced non-small cell lung cancer

The majority of patients with non-small cell lung cancer have locally advanced and metastatic disease at diagnosis. Combination platinum-based chemotherapy is the standard treatment for patients with advanced disease who have a performance status of 0-1. Chemotherapy is superior to supportive care alone in terms of survival, palliation of symptoms, and in many studies, improving quality of life. Newer third generation therapies such as paclitaxel, docetaxel, vinorelbine, and gemcitabine have been proven effective as single agents with minimal toxicity, compared with supportive care alone. In combination with platinum, these agents produce higher response rates than older platinum-based regimens, are associated with additional survival benefits, and are generally more convenient and less toxic for patients. Newer nonplatinum doublets appear equivalent to newer platinum-regimens and have expanded the options available for patients. Targeted agents are promising and may soon offer patients more effective and less toxic therapies. Progress in treatment in the advanced setting has led to advances in the care of locally advanced disease. Combination chemoradiotherapy is a standard treatment for locally advanced disease, and studies with newer agents are in progress.

ZD 1839 in patients with brain metastases from non-small-cell lung cancer (NSCLC): report of four cases

The activity of ZD 1839 on brain metastases (BM) from Non-Small-Cell Lung Cancer (NSCLC) is unknown. We report four cases of BM responding to ZD 1839 theraphy.