Advances in the treatment of malignant pleural mesothelioma

Malignant mesothelioma of the peritoneum mimicking primary peritonitis carcinomatosis

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Synthetic Secoisolariciresinol Diglucoside (LGM2605) Prevents Asbestos-Induced Inflammation and Genotoxic Cell Damage in Human Mesothelial Cells

Although alveolar macrophages play a critical role in malignant transformation of mesothelial cells following asbestos exposure, inflammatory and oxidative processes continue to occur in the mesothelial cells lining the pleura that may contribute to the carcinogenic process. Malignant transformation of mesothelial cells following asbestos exposure occurs over several decades; however, amelioration of DNA damage, inflammation, and cell injury may impede the carcinogenic process. We have shown in an in vitro model of asbestos-induced macrophage activation that synthetic secoisolariciresinol diglucoside (LGM2605), given preventively, reduced inflammatory cascades and oxidative/nitrosative cell damage. Therefore, it was hypothesized that LGM2605 could also be effective in reducing asbestos-induced activation and the damage of pleural mesothelial cells. LGM2605 treatment (50 µM) of huma n pleural mesothelial cells was initiated 4 h prior to exposure to asbestos (crocidolite, 20 µg/cm2). Supernatant and cells were evaluated at 0, 2, 4, and 8 h post asbestos exposure for reactive oxygen species (ROS) generation, DNA damage (oxidized guanine), inflammasome activation (caspase-1 activity) and associated pro-inflammatory cytokine release (IL-1β, IL-18, IL-6, TNFα, and HMGB1), and markers of oxidative stress (malondialdehyde (MDA) and 8-iso-prostaglandin F2a (8-iso-PGF2α). Asbestos induced a time-dependent ROS increase that was significantly (p < 0.0001) reduced (29.4%) by LGM2605 treatment. LGM2605 pretreatment also reduced levels of asbestos-induced DNA damage by 73.6% ± 1.0%. Although levels of inflammasome-activated cytokines, IL-1β and IL-18, reached 29.2 pg/mL ± 0.7 pg/mL and 43.9 pg/mL ± 0.8 pg/mL, respectively, LGM2605 treatment significantly (p < 0.0001) reduced cytokine levels comparable to baseline (non-asbestos exposed) values (3.8 pg/mL ± 0.2 pg/mL and 5.4 pg/mL ± 0.2 pg/mL, respectively). Furthermore, levels of IL-6 and TNFα in asbestos-exposed mesothelial cells were high (289.1 pg/mL ± 2.9 pg/mL and 511.3 pg/mL ± 10.2 pg/mL, respectively), while remaining undetectable with LGM2605 pretreatment. HMGB1 (a key inflammatory mediator and initiator of malignant transformation) release was reduced 75.3% ± 0.4% by LGM2605. Levels of MDA and 8-iso-PGF2α, markers of oxidative cell injury, were significantly (p < 0.001) reduced by 80.5% ± 0.1% and 76.6% ± 0.3%, respectively. LGM2605, given preventively, reduced ROS generation, DNA damage, and inflammasome-activated cytokine release and key inflammatory mediators implicated in asbestos-induced malignant transformation of normal mesothelial cells.

Survival after Pleural Malignant Mesothelioma a Population-based Study in Italy

Aims and Background

The study analyzed survival after malignant mesothelioma in the population-based Registry of Malignant Mesothelioma of Piedmont (NW Italy, 4.5 million total population). It focused on possible differences related to period of diagnosis a proxy of changes in diagnostic or therapeutic procedures.

Methods

Cases were actively searched in pathology units and files of hospital admissions and discharges. In 1990-1998, 693 incident cases were diagnosed in residents in the region: 590 of them had a histologic diagnosis of pleural mesothelioma in life and were included in the study. Vital status was ascertained at the municipality of residence as of January 1, 2000.

Results

Fifty-eight cases were alive (9.8%) and 20 were lost (3.6%) at the end of the follow-up. Median survival was 0.71 years (95% Cl, 0.64-0.78). Cumulative survival was 35.9% at 1 year (95% Cl, 32.0-39.8) and 14.2% at 2 years (95% Cl, 11.2-17.1). Survival was associated to age (longer survival for younger subjects at diagnosis; P <0.0001) and to histology (longer survival for epithelial mesothelioma, shorter for fibrous and intermediate for mixed or unspecified types; P <0.0001). There was no difference in survival for period of diagnosis. The results were confirmed in multivariate analyses. Analyses according to type of hospital (with vs without thoracic surgery) did not show any statistically significant difference.

Discussion

The study on survival after malignant mesothelioma is the second largest of the three population-based studies in the world, which showed results similar to ours. Survival measured in published clinical series ranged between 18.4% and 57.6% at 1 year for pleural and 24.1% and 33.8% for peritoneal mesothelioma. The most striking effect of the present study was the absence of improvement in survival with period of diagnosis. Either there was no change in treatment efficacy or the effect was limited to small subgroups and could not be noticed when the analysis included larger categories.

Synthetic Lignan Secoisolariciresinol Diglucoside (LGM2605) Reduces Asbestos-Induced Cytotoxicity in an Nrf2-Dependent and -Independent Manner

Asbestos exposure triggers inflammatory processes associated with oxidative stress and tissue damage linked to malignancy. LGM2605 is the synthetic lignan secoisolariciresinol diglucoside (SDG) with free radical scavenging, antioxidant, and anti-inflammatory properties in diverse inflammatory cell and mouse models, including exposure to asbestos fibers. Nuclear factor-E2 related factor 2 (Nrf2) activation and boosting of endogenous tissue defenses were associated with the protective action of LGM2605 from asbestos-induced cellular damage. To elucidate the role of Nrf2 induction by LGM2605 in protection from asbestos-induced cellular damage, we evaluated LGM2605 in asbestos-exposed macrophages from wild-type (WT) and Nrf2 disrupted (Nrf2⁻/⁻) mice. Cells were pretreated with LGM2605 (50 µM and 100 µM) and exposed to asbestos fibers (20 µg/cm²) and evaluated 8 h and 24 h later for inflammasome activation, secreted cytokine levels (interleukin-1β (IL-1β), interleukin-18 (IL-18), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNFα)), cytotoxicity and cell death, nitrosative stress, and Nrf2-regulated enzyme levels. Asbestos exposure induced robust oxidative and nitrosative stress, cell death and cytotoxicity, which were equally mitigated by LGM2605. Inflammasome activation was significantly attenuated in Nrf2^−/− macrophages compared to WT, and the protective action of LGM2605 was seen only in WT cells. In conclusion, in a cell model of asbestos-induced toxicity, LGM2605 acts via protective mechanisms that may not involve Nrf2 activation.

Effects of Combined Therapies on the Survival of Pleural Mesothelioma Patients Treated in Brescia, 1982–2006

Aims and background

During the 1990's, the traditional unimodal treatments (surgery, radiotherapy, chemotherapy, immunotherapy) for malignant pleural mesothelioma started to be combined in bimodal or multimodal strategies. However, recent population-based analyses of the survival of patients with malignant pleural mesothelioma indicate that even these treatments have not led to significant improvements in prognosis, which remains very poor. The present study assessed the survival of patients given combined treatments and multimodal therapies in a specialized hospital department.

Methods

The study population comprised 530 patients diagnosed with malignant pleural mesothelioma from 1982 to 2006: 343 of them were residents in the province of Brescia (Lombardy, Northern Italy) and 187 were residents outside the province, with a follow-up to 31 December 2009. Kaplan-Meier survival analyses and Cox proportional risks model were used to test sex, age at diagnosis, histological type and treatments, as prognostic factors.

Results

The estimated median survival for the whole group of patients was 317 days (257 for residents and 398 for non-residents), and respectively 310 and 340 days in the groups diagnosed in the periods 1982–2000 and 2001–2006. Multivariate analysis confirmed that the prognosis was better for younger patients and cases of epithelioid type malignant pleural mesothelioma, whereas for patients receiving any single treatment the prognosis was not significantly better than for those given palliative care alone. However, patients receiving combined treatments or the multimodality approach had significantly longer median survival and the relative risk of death was respectively 0.57 and 0.61 compared to untreated patients (or those only given symptomatic therapy).

Conclusions

This is the first study in Italy to assess the effectiveness of different treatment approaches in a significant number of patients treated in one hospital. Further studies are needed to confirm the improvement in prognosis – even if modest – on larger numbers of patients and taking into account the different stages of the disease.

Asbestos Induces Oxidative Stress and Activation of Nrf2 Signaling in Murine Macrophages: Chemopreventive Role of the Synthetic Lignan Secoisolariciresinol Diglucoside (LGM2605)

The interaction of asbestos fibers with macrophages generates harmful reactive oxygen species (ROS) and subsequent oxidative cell damage that are key processes linked to malignancy. Secoisolariciresinol diglucoside (SDG) is a non-toxic, flaxseed-derived pluripotent compound that has antioxidant properties and may thus function as a chemopreventive agent for asbestos-induced mesothelioma. We thus evaluated synthetic SDG (LGM2605) in asbestos-exposed, elicited murine peritoneal macrophages as an in vitro model of tissue phagocytic response to the presence of asbestos in the pleural space. Murine peritoneal macrophages (MFs) were exposed to crocidolite asbestos fibers (20 µg/cm²) and evaluated at various times post exposure for cytotoxicity, ROS generation, malondialdehyde (MDA), and levels of 8-iso Prostaglandin F2α (8-isoP). We then evaluated the ability of LGM2605 to mitigate asbestos-induced oxidative stress by administering LGM2605 (50 µM) 4-h prior to asbestos exposure. We observed a significant (p < 0.0001), time-dependent increase in asbestos-induced cytotoxicity, ROS generation, and the release of MDA and 8-iso Prostaglandin F2α, markers of lipid peroxidation, which increased linearly over time. LGM2605 treatment significantly (p < 0.0001) reduced asbestos-induced cytotoxicity and ROS generation, while decreasing levels of MDA and 8-isoP by 71%–88% and 41%–73%, respectively. Importantly, exposure to asbestos fibers induced cell protective defenses, such as cellular Nrf2 activation and the expression of phase II antioxidant enzymes, HO-1 and Nqo1 that were further enhanced by LGM2605 treatment. LGM2605 boosted antioxidant defenses, as well as reduced asbestos-induced ROS generation and markers of oxidative stress in murine peritoneal macrophages, supporting its possible use as a chemoprevention agent in the development of asbestos-induced malignant mesothelioma.

STAT6 siRNA matrix-loaded gelatin nanocarriers: formulation, characterization, and ex vivo proof of concept using adenocarcinoma cells

The clinical utility of siRNA therapy has been hampered due to poor cell penetration, nonspecific effects, rapid degradation, and short half-life. We herewith proposed the formulation development of STAT6 siRNA (S6S) nanotherapeutic agent by encapsulating them within gelatin nanocarriers (GNC). The prepared nanoformulation was characterized for size, charge, loading efficiency, release kinetics, stability, cytotoxicity, and gene silencing assay. The stability of S6S-GNC was also assessed under conditions of varying pH, serum level, and using electrophoretic assays. In vitro cytotoxicity performance was evaluated in human adenocarcinoma A549 cells following MTT assay. The developed formulation resulted in an average particle size, surface charge, and encapsulation efficiency as 70 ± 6.5 nm, +10 ± 1.5 mV, and 85 ± 4.0%, respectively. S6S-GNC showed an insignificant (P < 0.05) change in the size and charge in the presence of buffer solutions (pH 6.4 to 8.4) and FBS (10% v/v). A549 cells were treated with native S6S, S6S-lipofectamine, placebo-GNC, and S6S-GNC using untreated cells as a control. It was observed that cell viability was decreased significantly with S6S-GNC by 55 ± 4.1% (P < 0.001) compared to native S6S (2.0 ± 0.55%) and S6S-lipofectamine complex (40 ± 3.1%). This investigation infers that gelatin polymer-based nanocarriers are a robust, stable, and biocompatible strategy for the delivery of siRNA.

Malignant pleural mesothelioma: update on treatment options with a focus on novel therapies

There is evidence that improved treatments of malignant pleural mesothelioma are increasing the quality and quantity of life for patients with mesothelioma. Multimodality treatment programs that combine maximal surgical cytoreduction with novel forms of radiation therapy and more effective chemotherapy combinations may offer significant increases in survival for certain subgroups of patients with mesothelioma. Lung-sparing surgery may allow improvements in pulmonary function after surgery-based multimodality therapy, and potential longer overall survival than that seen with extrapleural pneumonectomy. Experimental treatments provide hope for all patients with mesothelioma, and in the future may be combined with standard therapy in multimodality protocols.

Malignant mesothelioma: a clinical study of 238 cases

Malignant mesothelioma is a diffuse tumor arising in the pleura, peritoneum, or other serosal surface and is closely associated with asbestos exposure. An estimated 2,500 to 3,000 cases are diagnosed each year in the United States. Although there are individual case reports and small series detailing the clinical aspects of mesothelioma, few studies examine a large series of patients with malignant mesothelioma from the clinical perspective. This study reports on the findings of 238 cases of malignant mesothelioma from a private consultative medical practice. Most cases had a history of occupational asbestos exposure. The mean latency was 48.5 yr, with women having a longer latency than men. The mean age at diagnosis was 70. Survival overall was poor (mean 8.8 months), but treatment was beneficial (mean 11.3 versus 6.4 months). Epithelioid histology conferred a survival advantage over sarcomatoid and responded better to treatment. Our data support an inverse relationship between asbestos dose and latency.

Targeted proteasome inhibition by Velcade induces apoptosis in human mesothelioma and breast cancer cell lines

INTRODUCTION

Thoracic malignancies and human breast cancer (HBC) continue to be aggressive solid tumors that are poor responders to the existing conventional standard chemotherapeutic approaches. Malignant pleural mesothelioma (MPM) is an asbestos-related tumor of the thoracic pleura that lacks effective treatment options. Altered ubiquitin proteasome pathway is frequently encountered in many malignancies including HBC and MPM and thus serves as an important target for therapeutic intervention strategies. Although proteasome inhibitor Velcade (Bortezomib) has been under clinical investigation for a number of cancers, limited preclinical studies with this agent have thus far been conducted in HBC and MPM malignancies.

PURPOSE

To study the biological and molecular responses of MPM and HBC cells to Velcade treatments, and to identify mechanisms involved in transducing growth inhibitory effects of this agent.

METHODS

Flow-cytometric analyses coupled with western immunoblotting and gene-array methodologies were utilized to determine mechanisms of Velcade-dependent growth suppression of five MPM (H2595, H2373, H2452, H2461, and H2714) and two breast cancer (MDA MB-468, SKBR-3) cell lines.

RESULTS

Our data revealed significant reduction in cell growth properties that were dose and time dependent. Velcade treatment resulted in G2M phase arrest, increased expression of cyclin-dependent kinase inhibitor p21 and pro-apoptotic protein Bax. Pretreatment of mesothelioma cells with Velcade showed synergistic effect with cisplatin combination regimens. High-throughput gene expression profiling among Velcade treated and untreated mesothelioma cell lines resulted in identification of novel transducers of apoptosis such as CARP-1, XAF1, and Troy proteins.

CONCLUSIONS

Velcade targets cell cycle and apoptosis signaling to suppress MPM and HBC growth in part by activating novel transducers of apoptosis. This pilot study has paved way for further in-depth analysis of the downstream target molecules associated with presensitization of mesothelioma cells in finding effective therapeutic treatment options for both mesothelioma and recalcitrant breast cancers.

Pemetrexed plus cisplatin or pemetrexed plus carboplatin for chemonaïve patients with malignant pleural mesothelioma: results of the International Expanded Access Program

INTRODUCTION

Previously published results from a randomized phase III study of pemetrexed plus cisplatin in patients with malignant pleural mesothelioma (MPM) demonstrated a significant survival benefit and higher response rate compared with cisplatin. Although pemetrexed was under review by regulatory agencies, an International Expanded Access Program (EAP) provided more than 3000 mesothelioma patients with access to single-agent pemetrexed or pemetrexed in combination with cisplatin or carboplatin in 13 countries. This manuscript reports the safety and efficacy data from the nonrandomized open-label study in chemonaïve patients receiving pemetrexed plus platinum under the EAP.

METHODS

Patients with histologically confirmed MPM, not amenable to curative surgery, received pemetrexed 500 mg/m in combination with either cisplatin 75 mg/m or carboplatin AUC 5, once every 21 days with standard premedication. Efficacy data were recorded at the end of study participation.

RESULTS

A total of 1704 chemonaïve patients received pemetrexed plus cisplatin (n = 843) or pemetrexed plus carboplatin (n = 861) and were evaluated for safety. The efficacy evaluable population consisted of 745 patients in the pemetrexed plus cisplatin group and 752 patients in the pemetrexed plus carboplatin group for whom physician-reported tumor response was available. The pemetrexed plus cisplatin group demonstrated a response rate of 26.3% compared with 21.7% for the pemetrexed plus carboplatin group, with similar 1-year survival rates (63.1% versus 64.0%) and median time to progressive disease (7 months versus 6.9 months). The most common grade 3/4 hematologic toxicity was neutropenia in 23.9% of the pemetrexed plus cisplatin group and 36.1% of the pemetrexed plus carboplatin group.

CONCLUSION

This large EAP confirmed the activity of pemetrexed plus cisplatin and pemetrexed plus carboplatin in chemonaïve patients with MPM, demonstrating clinically similar time to progressive disease and 1-year survival rates.

Intracavitary radioimmunotherapy to treat solid tumors

Radioimmunotherapy (RIT) potentially is an attractive treatment for radiosensitive early-stage solid tumors and as an adjuvant to cytoreductive surgery. Topical administration of RIT may improve the efficacy because higher local concentrations are achieved. We reviewed the results of locally applied radiolabeled monoclonal antibodies for the treatment of solid tumors. Intracavitary RIT in patients with ovarian cancer and glioma showed improved targeting after local administration, as compared to the intravenous administration. In addition, various studies showed the feasibility of locally applied RIT in these patients. In studies that included patients with small-volume disease, adjuvant RIT in ovarian cancer and glioma showed to be at least as effective as standard therapy. The information about RIT for peritoneal carcinomatosis of colorectal origin is scarce, while results from preclinical data are promising. RIT may be applied for other, relatively unexplored indications. Studies on the application of radiolabeled antibodies in early urothelial cell cancer have been performed, showing that intracavitary RIT may hold a promise. Moreover, in patients with malignant pleural mesothelioma or malignant pleural effusion, RIT may play a role in the palliative treatment. Intracavitary RIT limits toxicity and improves tumor targeting. RIT is more effective in patients with small-volume disease of solid cancers. RIT may have potential for palliation in patients with malignant pleural mesothelioma or malignant pleural effusion. The future of RIT may, therefore, not only be in the inclusion in contemporary multimodality treatment, but also in the expansion to palliative treatment.

A retrospective analysis of malignant pleural mesothelioma patients treated either with chemotherapy or best supportive care between 1990 and 2005 A single institution experience

The aim of this study was to investigate the efficacy and safety profile of chemotherapy (CT) compared to best supportive care (BSC) in patients with histopathologically confirmed diffuse malignant pleural mesothelioma (DMPM). A total of 161 patients between 1990 and 2004 treated either with CT (109 patients) or BSC (52 patients) depending on patients choice were evaluated in this analyses. Chemotherapy protocols included a combination of cisplatin, mitomycin C and recombinant interferon alpha 2a (CM-In), or cisplatin, mitomycin C and ifosfamide (CMI), or cisplatin and gemcitabine (CG). We found a significant difference in the median survivals of the patients with CT compared to BSC, 11.3 months versus 8.0. Objective response rate was 28/109 (25.7%) with 3.7% of complete response rate. Stable disease rate was 39/109 (35.8%). There was a significant difference between median survivals of patients with objective response (17 months) and median survivals of patients with progressive diseases (6 months) and also with stable diseases (16 months). There was a significant difference between the stable disease and the progressive disease. Stages 3 and 4 patients of epithelial cell type having received chemotherapy live longer than those not having received chemotherapy (12 months versus 4). There was no significant difference between the survivals of the different chemotherapy regimens. The toxicity with CT regimens were mild and well-tolerated. We conclude that CT prolongs survival compared to BSC in patients with DMPM. Survivals of patients with objective response prolong considerably with CT compared BSC. We observed that stages 3 and 4 patients with epithelial cell type got benefit from CT. Especially, of epithelial cell type stages 1 and 2 should receive multimodal treatment.

EGFR expression: associations with outcome and clinicopathological variables in malignant pleural mesothelioma

Malignant mesothelioma (MM) is a fatal tumour of increasing incidence which is related to asbestos exposure. This work evaluated expression in MM of Epidermal Growth Factor Receptor (EGFR) by immunohistochemistry in 168 tumour sections and its correlations with clinicopathological and biological factors. The microvessel density (MVD) was derived from CD34 immunostained sections. Hematoxylin and eosin stained sections were examined for intratumoural necrosis. COX-2 protein expression was evaluated with semi-quantitative Western blotting of homogenised tumour supernatants (n=45). EGFR expression was correlated with survival by Kaplan-Meier and log rank analysis. Univariate and multivariate Cox proportional hazards models were used to compare the effects of EGFR with clinicopathological and biological prognostic factors and prognostic scoring systems. EGFR expression was identified in 74 cases (44%) and correlated with epithelioid cell type (p<0.0001), good performance status (p<0.0001), the absence of chest pain (p<0.0001) and the presence of TN (p=0.004), but not MVD or COX-2. EGFR expression was a good prognostic factor in univariate analysis (p=0.01). Independent indicators of poor prognosis in multivariate analysis were non-epithelioid cell type (p=0.0001), weight loss, performance status and WBC>8.3x10(9)L(-1). EGFR status was not an independent prognostic factor. EGFR expression in MM correlates with epithelioid histology and TN. EGFR may be a target for selective therapies in MM.

Comparative genomic hybridisation in malignant deciduoid mesothelioma

BACKGROUND

Malignant deciduoid mesothelioma is a rare variant of epithelioid mesothelioma. This tumour generally has poor prognosis, and can be asbestos related.

AIM

To identify peculiar genetic changes responsible for critical phases in pathogenesis of malignant deciduoid mesothelioma and their prognostic relevance.

METHODS

Comparative genomic hybridisation was carried out in six cases of malignant pleural deciduoid mesothelioma, four sporadic and two familial. All cases were found to be asbestos related. Four patients died during follow-up and the mean survival was 29.5 (SD 14.2, range 12-43) months.

RESULTS

Genetic abnormalities were found in all the tumour tissues, the most frequent being chromosomal gains at 1p, 12q, 17, 8q, 19 and 20 and losses at 13q, 6q and 9p. Survival was found to be longer in those patients who presented a smaller number of losses (< or =2) in the tumorous chromosomes.

CONCLUSIONS

Although numerous genetic changes are presented by deciduoid mesotheliomas, certain chromosomal regions are preferentially affected. The clinical outcome for this mesothelioma subtype is predicted by the number of losses.

Management of Malignant Pleural Mesothelioma

Malignant mesothelioma is increasing in incidence globally and has no known cure. Its unique clinical feature of local infiltration along tissue planes makes it a difficult neoplasm to manage. There have been few randomized controlled trials regarding treatment options, although these have increased in recent years, and results are eagerly awaited. This article summarizes important advances in the management of mesothelioma, especially diagnostic and therapeutic aspects.

Intrapleural topical application of cisplatin with the surgical carrier Vivostat increases the local drug concentration in an immune-competent rat model with malignant pleuromesothelioma

OBJECTIVE

We sought to investigate whether intrapleural topical application of cisplatin with a surgical carrier has a prolonged local tissue level in comparison with cisplatin solution while reducing systemic toxicity.

METHODS

Forty immune-competent Fischer rats were inoculated with 10(6) mesothelioma cells. Ten days later, left pneumonectomy with tumor debulking was performed. Twenty animals underwent local application of cisplatin solution (100 mg/m2), whereas the same quantity of cisplatin was topically applied as a gel with the Vivostat (Vivolution) system in 20 other animals. In each group 5 subgroups of 4 animals were defined according to the harvesting time of blood and tissue samples (2, 4, 24, and 72 hours and 1 week) after local therapy. Platinum concentrations in serum and tissue and systemic toxicity were analyzed.

RESULTS

Platinum concentrations in tissue were significantly higher in the gel group (group 1) than in the solution group (group 2) at 1, 3, and 7 days after therapy (1510, 1224, and 1069 pg/mg for group 1 vs 598, 382, and 287 pg/mg for group 2; P = .007, P = .005, and P = .0002, respectively). Laboratory findings showed renal insufficiency in the animals of the solution group at 1 week, with values of 98 mmol/L versus 7.7 mmol/L for urea and 410 mumol/L versus 43 mumol/L for creatinine (P = .02 and P = .01, respectively), which was confirmed by means of pathologic analysis.

CONCLUSIONS

Intrapleural administration of cisplatin with the carrier Vivostat significantly provides sustained higher platinum concentrations up to 1 week in tissue in comparison with application of cisplatin solution without conferring systemic toxicity in this model.

Bisphosphonates Inhibit the Growth of Mesothelioma Cells In vitro and In vivo

PURPOSE

Bisphosphonates (such as risedronate and zoledronate) are widely used inhibitors of bone resorption. Despite their in vitro antiproliferative effects in various cancer cells, bisphosphonates have not exhibited significant antitumor efficacy in animal models of visceral cancer, which may be due to their poor bioavailability. The diagnostic use of radioactive bisphosphonates has revealed the accumulation of bisphosphonates in mesothelioma, which prompted us to test the antitumor efficacy of bisphosphonates in this disease.

EXPERIMENTAL DESIGN AND RESULTS

Treatment with either risedronate or zoledronate (2 x 10(-4) to 2 x 10(-6) mol/L) inhibited the growth of AB12 and AC29 mouse mesothelioma cells and induced the accumulation of unprenylated Rap1A in these cells. Both these in vitro effects were reversed by geranygeraniol, an end product of the mevalonate pathway that these bisphosphonates inhibit. Both bisphosphonates also induced the phosphorylation of the p38 mitogen-activated protein kinase in AB12 and AC29 cells. The inhibition of p38 augmented bisphosphonate-induced growth inhibition in these cells. Bisphosphonate-induced p38 phosphorylation was not reversible by geranylgeraniol. Risedronate (15 mg/kg) and zoledronate (0.5 mg/kg) inhibited the growth of s.c. tumors and increased the median survival of mice with i.p. mesothelioma tumors in vivo.

DISCUSSION

In conclusion, risedronate and zoledronate inhibit the mevalonate pathway and induce p38 activation in mesothelioma cells in vitro. The effects on the mevalonate pathway dominate because the net result is growth inhibition. Both bisphosphonates also inhibit mesothelioma tumor growth in vivo and prolong the survival of mesothelioma-bearing mice. These results support further study of bisphosphonates in the management of mesothelioma.

A novel radiation therapy technique for malignant pleural mesothelioma combining electrons with intensity-modulated photons

BACKGROUND AND PURPOSE

To investigate the feasibility and potential benefits of combining electron and photon intensity modulated radiotherapy (IMRT) for patients with malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

The planning CT images of 11 MPM patients, six after extrapleural pneumonectomy (EPP) and five after pleurectomy/decortication (P/D), were used for this study. These cases were planned with photon IMRT alone and photon IMRT combined with electrons (IMRT+e). The latter approach incorporated the electron dose into the inverse planning optimization. The resulting doses to the planning target volume (PTV) and relevant critical structures were compared.

RESULTS

For all patients, the PTV was well covered and doses to critical structures were clinically acceptable for all patients with both techniques. However, IMRT+e exhibited a distinct advantage in reducing the doses to the liver, ipsilateral kidney, contralateral kidney, and heart (P=0.002, 0.003, 0.025, and 0.001, respectively).

CONCLUSIONS

This study showed that IMRT or IMRT+e is a viable treatment modality for MPM patients. Both plans can provide excellent target coverage and normal tissue sparing, but with the addition of electron beams, the critical structures can be further spared. Additional refining of the electron contribution is expected to further reduce radiation-induced morbidity.

Gene Therapy for Malignant Pleural Mesothelioma

Gene therapy for mesothelioma is currently in its adolescence. The expansion of knowledge regarding molecular aspects of mesothelioma carcinogenesis has facilitated the development of promising gene therapy modalities that target specific oncoproteins and mutant tumor suppressor genes. Although implementation of any of these gene therapy approaches as part of standard medical care for patients who have mesothelioma remains years in the future, the field is finally progressing toward more definitive phase II/III efficacy studies. Unfortunately, the marginal benefits garnered from standard anticancer treatments in mesothelioma argue strongly for continued participation in clinical studies of various experimental approaches, particularly gene therapy. These trials serve multiple purposes: to establish safety, determine proper dosing, evaluate for efficacy, and, in an iterative fashion, guide future avenues of laboratory investigation.

Malignant Pleural Mesothelioma: A Case Report

OBJECTIVE

The aim of this study was to discuss a case of malignant pleural mesothelioma (MPM) that presented to a chiropractic teaching clinic and review the pathophysiology of diseases associated with asbestos exposure.

CLINICAL FEATURES

An 86-year-old woman had right-sided back pain at the thoracolumbar junction for 3 months; this pain prevented her from exercising on a daily basis. She was alert and oriented but in obvious distress because of her back pain. Breath sounds were decreased on the right in the posterior and lower lobes, with dull percussion and increased tactile fremitus. A significant collection of pleural effusion was seen on the right side on plain film radiographs. A chest computed tomography with contrast showed a large right-sided pleural effusion with small consolidation at the right lung base suggestive of pleural or pulmonary malignancy and highly suspicious for MPM. Further questioning about asbestos exposure revealed that her husband was a maintenance worker. An extrapleural pneumonectomy was performed, and specimens of parietal and visceral pleura were sent for pathological, which revealed a definitive diagnosis of spindle cell mesothelioma.

INTERVENTION AND OUTCOME

The patient was diagnosed with MPM, and a surgical therapy option was considered because of the aggressive nature of the lesion and her advanced age. An extrapleural pneumonectomy was performed with removal of parietal and visceral pleura, right lower lobe, and right hemidiaphragm.

CONCLUSION

This is an unusual case of advanced MPM that is most likely from indirect asbestos exposure.

Photodynamic therapy in the management of malignant pleural mesothelioma: A review

BACKGROUND

In the past decade there have been sporadic publications on malignant pleural mesothelioma (MPM). In the present trend of multi-modal treatment for MPM we aim to evaluate the current status of photodynamic therapy (PDT) in the management of MPM through a review study.

METHODS

Original publications in English were the main source of the review and their material analysed in respect of patient and disease characteristics, PDT methods, mortality and morbidity and survival. Ten articles concerned with 230 patients were analysed and 35 other publications relevant to the study were used for reference. In every case PDT was used as an adjuvant to surgery whose role appeared to be a cyto-reductive procedure of debulking, pleurectomy and decortication (DPD) with/without pulmonary resection. PDT methods used two photosensitisers; Photofrin™ [630nm laser light] (6 series=170 patients) or Foscan™ [652nm laser light] (4 series=60 patients).

RESULTS

Overall mortality and morbidity was 7.1% (4.9% for Photofrin™ and 13.3% for Foscan™ PDT) and 48% (38% for Photofrin™ and 70% for Foscan™ PDT) respectively. Better survival was achieved for DPD and early stage disease.

CONCLUSIONS

Intra-operative (IOP) PDT in MPM is a safe procedure that requires more development and work regarding photosensitisers and light distribution systems for use in intra-pleural situations. The role of surgery in IOP-PDT appears to be cyto-reduction to ≤5mm residual tumour thickness in order for PDT to be used effectively. Curative intent may depend on the stage of MPM and completeness of cyto-reduction with/without pulmonary resection.

Measuring quality of life in patients with pleural mesothelioma using a modified version of the Lung Cancer Symptom Scale (LCSS): psychometric properties of the LCSS-Meso

Health-related quality of life (QOL) assessment is a key component in patient assessment and the development of therapies for malignant pleural mesothelioma. However, no mesothelioma-specific instrument was available. The Lung Cancer Symptom Scale (LCSS), a site-specific instrument used to assess QOL in patients with lung cancer, was identified as an instrument that could be appropriate. A modified nine-item patient-reported and six-item observer-reported LCSS was incorporated into two clinical trials of pemetrexed in patients with pleural mesothelioma. Basic psychometric properties of feasibility, reliability, and validity were tested. Properties were stable or enhanced by deletion of the hemoptysis item. Feasibility was demonstrated with a high completion rate of 90% by 512 patients. Reliability was acceptable, with good internal consistency for the eight-item measure (alpha coefficient=0.86) and reasonably good for the five-item observer measure (alpha coefficient=0.66); there was also good stability for the patient measure using test-retest (r=0.87). Content validity was supported by a literature review and patient self-report of presenting symptoms (>90% of patients had three or more symptoms). Construct validity was well supported by finding better scores in the higher performance status groups and greater symptom improvement in patients with tumor response, good concordance with the LCSS conceptual model and good explanation of variance for summation items, and a high degree of convergence between the patient and observer forms (r=0.57). Criterion-related validity was supported by predicting survival time, time to progression, and tumor response rate; all three summary items and the total LCSS-Meso score were statistically significant predictors (p<0.005). The LCSS-Meso is a feasible, reliable, and valid instrument to assess health-related QOL in patients with pleural mesothelioma. One item, hemoptysis, was dropped from the original LCSS based on these findings.

Induction chemotherapy, extrapleural pneumonectomy, and radiotherapy in the treatment of malignant pleural mesothelioma: The Memorial Sloan-Kettering experience

Approximately 25% of patients with malignant pleural mesothelioma (MPM) prove unresectable at surgery and the median survival of stage III MPM is <12 months even after complete resection by extrapleural pneumonectomy. From 1939-2004, a series of sequential clinical trials has been performed at our institution. The surgical procedure has been modified and improved upon, and adjuvant hemithoracic radiation (RT) standardized. The evolution of our current standard of care for MPM is discussed. Improving chemotherapy for MPM led us to test induction chemotherapy followed by EPP and adjuvant RT for locally advanced MPM to assess feasibility. Patients with T3-4 or N2 MPM by CT and PET scans were enrolled on a phase II study. Induction therapy was: gemcitabine (1250 mg/m2 days 1, 8) and cisplatin (75 mg/m2 day 8)x2-4 cycles. Patients underwent EPP 3-5 weeks after induction therapy, then 54 Gy RT 4-6 weeks postop. At surgery, 8/9 had complete resection by EPP with no postoperative deaths. All received planned adjuvant RT. This combined modality approach is feasible for locally advanced MPM, and initial analysis suggests improved resectability. This experience supports additional studies of induction and multimodality therapy, especially with regimens such as cisplatin and pemetrexed which may be better tolerated and more effective.

Second-line (post-study) chemotherapy received by patients treated in the phase III trial of pemetrexed plus cisplatin versus cisplatin alone in malignant pleural mesothelioma

BACKGROUND

A phase III trial in patients with malignant pleural mesothelioma demonstrated a survival advantage for pemetrexed plus cisplatin compared with single-agent cisplatin. Because post-study chemotherapy (PSC) may have influenced the outcome of the trial, we examined its use and association with survival.

PATIENTS AND METHODS

Eighty-four patients from the pemetrexed plus cisplatin arm and 105 patients from the single-agent cisplatin arm received PSC. Kaplan-Meier survival estimates were compared by treatment groups, and by PSC and non-PSC subgroups.

RESULTS

The percentage of patients receiving PSC was imbalanced between the treatment arms. Fewer pemetrexed plus cisplatin treated patients received PSC (37.2% versus 47.3%). A multiple regression analysis performed in this trial showed that PSC had a statistically significant correlation with prolonged survival (P <0.01), adjusting for baseline prognostic factors and treatment intervention. The adjusted hazard ratio for PSC over non-PSC subgroups was 0.56 (confidence interval 0.44-0.72).

CONCLUSIONS

PSC in malignant pleural mesothelioma was significantly associated with prolonged survival. It is not known whether the reduced risk of death was associated with PSC or whether patients who had prolonged survival tended to receive more PSC. The pemetrexed plus cisplatin treatment group had a statistically significant survival advantage even though fewer patients from that arm of the trial received PSC. The potentially beneficial role of PSC should be assessed in prospective trials.

Immunotherapy of Murine Malignant Mesothelioma Using Tumor Lysate–pulsed Dendritic Cells

RATIONALE

Exploiting the immunostimulatory capacities of dendritic cells holds great promise for cancer immunotherapy. Currently, dendritic cell-based immunotherapy is evaluated clinically in a number of malignancies, including melanoma and urogenital and lung cancer, showing variable but promising results.

OBJECTIVE

To evaluate if pulsed dendritic cells induce protective immunity against malignant mesothelioma in a mouse model.

METHODS

Malignant mesothelioma was induced in mice by intraperitoneal injection of the AB1 mesothelioma cell line, leading to death within 28 days. For immunotherapy, dendritic cells were pulsed overnight either with AB1 tumor cell line lysate, AB1-derived exosomes, or ex vivo AB1 tumor lysate, and injected either before (Days -14 and -7) at the day of (Day 0) or after (Days +1 and +8) tumor implantation.

MAIN RESULTS

Mice receiving tumor lysate-pulsed dendritic cells before tumor implantation demonstrated protective antitumor immunity with prolonged survival (> 3 months) and even resisted secondary tumor challenge. Tumor protection was associated with strong tumor-specific cytotoxic T-lymphocyte responses. Adoptive transfer of splenocytes or purified CD8+ T lymphocytes transferred tumor protection to unimmunized mice in vivo. When given after tumor implantation in a therapeutic setting, pulsed dendritic cells prevented mesothelioma outgrowth. With higher tumor load and delayed administration after tumor implantation, dendritic cells were no longer effective.

CONCLUSIONS

We demonstrate in this murine model that immunotherapy using pulsed dendritic cells may emerge as a powerful tool to control mesothelioma outgrowth. In the future, immunotherapy using dendritic cells could be used as adjuvant to control local recurrence after multimodality treatment for malignant mesothelioma.

Ifosfamide, mesna, and interferon-alpha2A combination chemoimmunotherapy in malignant mesothelioma: results of a single center in central anatolia

Our aim was to determine the efficacy of ifosfamide, mesna, and interferon alpha combination therapy in malignant mesothelioma (MM) patients. Fourty-two patients (39 evaluable) with histologically proven MM were enrolled into this study from January 1999 to October 2002. The drug schedule consisted of a combination of ifosfamide, 3000 mg/m2 1-3 d intravenous infusion (iv), the uroprotective agent mesna, 3000 mg/m2 1-3 d iv every 3 wk, and interferon alpha2a, 4.5 MU subcutaneously (sc) 3 d/wk for 6 mo as first-line chemotherapy. Overall, 140 cycles were administered to the 39 patients (median, 3.5 cycles; range, 1 to 6 cycles). Among the 39 patients, 8 partial remissions (PR) (21%) were observed. Thirteen patients (33%) had stable disease for at least 8 wk and 18 (46%) had progressive disease. Overall survival (OAS) and progression free survival (PFS) for all patients were 10.0 +/- 2.9 mo (95%CI 4.3-15.7) and 5.0 +/- 1.9 mo (95%CI 1.38-8.62), respectively. One and two year survival rates were calculated as 39% and 5%, respectively. All of the PR patients had the epithelial type of MM. Their survival time was 21.0 +/- 5.7 mo (95% CI 9.9-32.1) and significantly longer than that of nonresponders (p=0.0061). The toxicity of the drug combination was mild and well tolerated. There were no treatment-related deaths. Grade 3-4 neutropenia and febrile neutropenia were seen in 10 patients (26%) and 3 patients (8%), respectively. Chemotherapy was stopped in three patients because of renal function deficiency. One of these patients who had peritoneal MM required hemodialysis. In conclusion, this combination therapy showed encouraging antitumor activity with modest toxicity.

The palliative benefits of MVP (mitomycin C, vinblastine and cisplatin) chemotherapy in patients with malignant mesothelioma

BACKGROUND

With the rising incidence of malignant mesothelioma (MM), it is important to optimise treatment to control symptoms, maintain quality of life and, if possible, prolong life. We have analysed prospectively collected data to evaluate a frequently used palliative chemotherapy regimen.

PATIENTS AND METHODS

Between October 1986 and May 2002 all patients with inoperable pleural mesothelioma were considered for treatment with MVP (mitomycin C 8 mg/m2 every 6 weeks, vinblastine 6 mg/m2 every 3 weeks and cisplatin 50 mg/m2 every 3 weeks) chemotherapy. Symptoms were assessed by physician assessment at baseline and after each cycle of chemotherapy.

RESULTS

One hundred and fifty patients were treated with MVP for mesothelioma. Forty-three per cent had a performance status (PS) 2 or worse. The response rate was 15.3%, with 68.6% having stable disease. Sixty-nine per cent reported an improvement in symptoms; in particular there were good responses for pain (71%), cough (62%) and dyspnoea (50%). The most common grade 3/4 toxicity was neutropenia (22%). Median overall survival was 7 months, with 1-year survival 31% and 2-year survival 11%. Median survival for patients with PS 0/1 was 10 months, and was 6 months for patients with PS 2/3. Poor prognostic factors in univariate analysis included poor PS, weight loss, mixed or sarcomatoid histology, low haemoglobin and high white blood cell count. Excluding pathological subtype, the prognostic significance of poor PS and weight loss were retained in multivariate analysis.

CONCLUSIONS

Palliation of symptoms in MM is achievable with current cisplatin-based treatments.

The pathology associated with therapeutic procedures in malignant mesothelioma

AIMS

To describe iatrogenic pathological lesions in malignant pleural mesothelioma.

METHODS AND RESULTS

All cases of malignant pleural mesothelioma confirmed by antemortem pleural biopsy and undergoing post mortem examination over a 7-year period (1995-2001) formed the study group. This comprised 48 malignant pleural mesotheliomas [epithelioid (n = 21), biphasic (n = 14) and sarcomatoid (n = 13)]. Twenty-eight of 48 (58%) had received chemical (talc) pleurodesis, 30/48 (63%) palliative localized radiotherapy, 6/48 (13%) chemotherapy, and 14/48 (30%) surgery [12/48 (26%) pleural decortication and 2/48 (4%) pleuropneumonectomy].

CONCLUSIONS

Talc pleurodesis induces a marked pseudosarcomatous fibroblastic proliferation which may impart a biphasic pattern to the neoplasm. In more chronic cases, paucicellular fibrosis with a foreign body giant cell reaction is noted. The talc is polarizable and deposited in linear fashion within the tumour. In 2/28 (7%) pleurodesis cases platyform ferruginous bodies were seen in the peripheral alveolated lung parenchyma and these mimicked asbestos bodies. An awareness of this is important to prevent false attribution to asbestos. Talc could be identified by transmission electron microscopic mineral analysis in 5/15 (33%) cases examined. Tumour nodules developing subjacent to iatrogenic wound sites were noted in 8/48 (17%) cases. In 6/8 (75%) of these cases, comparative assessment of the locally irradiated subcutaneous chest wall tumour, with background pleural mesothelioma, showed no morphological difference in architectural tumour growth pattern, extent of necrosis, cytological or nuclear pleomorphism, mitotic activity or tumour immunophenotype. In 2/8 (25%) cases the locally irradiated tumour showed prominent bizarre multinucleated tumour giant cells and intense mixed inflammation, a feature not seen in the background (non-irradiated) tumour. All six malignant pleural mesotheliomas receiving chemotherapy appeared refractory to treatment in that chemotherapy did not appear to have any significant effect on the tumour morphology, cytonuclear pleomorphism, mitotic activity, extent of necrosis or immunophenotype. In the 12 decortication specimens and two pleuropneumonectomy resections, post mortem examination identified evidence of residual malignant mesothelioma of similar morphological subtype and immunophenotype to the resected tumour.

Current chemotherapeutic treatment of malignant pleural mesothelioma

Malignant pleural mesothelioma is an aggressive malignancy which is almost always fatal; median survival is usually < 1 year. Most patients present with symptoms including pain, dyspnoea, pleural effusions and chest wall masses. Until recently, there has been no effective treatment which can improve symptoms and prolong survival. This article reviews recent developments in the treatment of mesothelioma, particularly advances in drug therapy and the use of the current most active drug combination: pemetrexed and cisplatin. Pemetrexed is a novel antifolate drug with multiple enzyme targets. The combination of pemetrexed and cisplatin demonstrated a survival advantage over cisplatin alone in patients with pleural mesothelioma, and can give symptomatic benefits. This combination has become the standard of care in mesothelioma treatment.

Soluble type II transforming growth factor-beta receptor inhibits established murine malignant mesothelioma tumor growth by augmenting host antitumor immunity

PURPOSE

Transforming growth factor (TGF)-beta blockade has been proposed as an anticancer therapy; however, understanding which tumor patients might benefit most from such therapy is crucial. An ideal target of such inhibitory therapy might be malignant mesothelioma (MM), a highly lethal, treatment-resistant malignancy of mesothelial cells of the pleura and peritoneum that produces large amounts of TGF-beta. The purpose of this study was to explore the possible therapeutic utility of TGF-beta blockade on MM.

EXPERIMENTAL DESIGN

To evaluate this hypothesis, we tested the effects of a soluble TGF-beta type II receptor (sTGF-beta R) that specifically inhibits TGF-beta1 and TGF-beta 3 in three different murine MM tumor models, AB12 and AC29 (which produce large amounts of TGF-beta) and AB1 (which does not produce TGF-beta).

RESULTS

Tumor growth of both established AB12 and AC29 tumors was inhibited by sTGF-beta R. In contrast, AB1 tumors showed little response to sTGF-beta R. The mechanism of these antitumor effects was evaluated and determined to be primarily dependent on immune-mediated responses because (a) the antitumor effects were markedly diminished in severe combined immunodeficient mice or mice depleted of CD8(+) T cells and (b) CD8(+) T cells isolated from spleens of mice treated with sTGF-beta R showed strong antitumor cytolytic effects, whereas CD8(+) T cells isolated from spleens of tumor-bearing mice treated with of control IgG2a showed no antitumor cytolytic effects.

CONCLUSIONS

Our data suggest that TGF-beta blockade of established TGF-beta-secreting MM should be explored as a promising strategy to treat patients with MM and other tumors that produce TGF-beta.

Surgical management of malignant pleural mesothelioma: a systematic review and evidence summary

An evidence summary was developed for the surgical management of adult patients with diffuse or localized malignant pleural mesothelioma. This evidence summary is based on a systematic search and review of the literature published between 1985 and February 2004. Relevant studies were identified, according to pre-determined criteria by the authors and methodologists. No randomized controlled trials comparing pleurectomy (PL) with extrapleural pneumonectomy (EPP) or comparing surgery with an alternative treatment were identified. Four comparative studies, seven non-comparative prospective studies, and 16 retrospective case series were identified that looked at PL, or EPP, or PL and EPP. Trial results were not pooled due to the heterogeneity of the treatments in the trials and the fact that no trials were randomized and none were designed to directly compare different treatments. External feedback was obtained from Ontario clinicians, and the provincial Lung Cancer Disease Site Group approved the review.

CONCLUSIONS

The role of surgery in the management of malignant pleural mesothelioma cannot be precisely defined as the lack of randomized controlled clinical trials makes it impossible to determine whether the use of EPP or PL improves survival or effectively palliates the symptoms of the disease. Future studies of the role of surgery in the treatment of mesothelioma should include evaluations of quality of life.

Preoperative assessment and therapeutic options for patients with malignant pleural mesothelioma

Prompt medical evaluation and aggressive treatment can lead to prolonged survival or successful palliation of symptoms for patients with malignant pleural mesothelioma, but the window for implementing treatment is short. Clinical recognition of the cancer is confounded by numerous factors, including long latency between exposure to asbestos and expression of the disease, nonspecific nature of the presenting symptoms, rarity of the disease, a lack of experience in clinical diagnosis, and rapidly deteriorating clinical course after diagnosis. Heightened clinical suspicion and proper patient selection through accurate staging and pathologic identification are paramount to defining and delivering therapy for this rare, lethal cancer.

HMBA induces cell death and potentiates doxorubicin toxicity in malignant mesothelioma cells

PURPOSE

Malignant pleural mesothelioma(MM), a rare tumor characterized by high local invasiveness and low metastatic efficiency, is poorly responsive to current therapeutic approaches. The aim of the present study was to evaluate the cytotoxic efficacy of the hybrid polar compound hexamethylene bisacetamide(HMBA), either as a single agent or in combination with the anthracycline doxorubicin (DOX), against MM cells.

METHODS

The MM cell lines MM-B1 and MM-El were treated with HMBA, DOX or with combinations of the two drugs. Cell survival and death were assessed by the MTS assay and trypan blue staining/TUNEL, respectively. The interactions between drugs were evaluated by the method of Kern et al. Western blot analysis was used to investigate the expression of Bcl-2 family proteins.

RESULTS

When administered alone, HMBA dose-dependently decreased the number of viable cells and increased the death rate of MM-B1 and MM-E1 cultures. Combinations of HMBA and DOX achieved a synergistic inhibition of MM cell survival, and the simultaneous administration of HMBA counteracted the resistance induced by DOX in MM-El cells. HMBA,used at cytostatic concentrations, reduced the ratio be-tween antiapoptotic (Bcl-2, Bcl-XL) and proapoptotic(Bax) members of the Bcl-2 family of proteins, thus lowering the threshold for MM cell death commitment.

CONCLUSIONS

HMBA has therapeutic potential in MM both as a single agent and through potentiation of DOX toxicity. These results support future investigations on the feasibility of intrapleural chemotherapy with this hybrid polar compound.

Carboplatin/Paclitaxel or Carboplatin/Vinorelbine Followed by Accelerated Hyperfractionated Conformal Radiation Therapy: Report of a Prospective Phase I Dose Escalation Trial From the Carolina Conformal Therapy Consortium

Purpose

To prospectively determine the maximum-tolerated dose of accelerated hyperfractionated conformal radiotherapy (RT; 1.6 Gy bid) for unresectable locally advanced lung cancer (IIB to IIIA/B) following induction carboplatin/paclitaxel (C/T) or carboplatin/vinorelbine (C/N).

Methods

Induction chemotherapy, C/T or C/N, was followed by escalating doses of conformally-planned RT (73.6 to 86.4 Gy in 6.4-Gy increments). Concurrent boost methods delivered 1.6 and 1.25 Gy bid to the gross and clinical target volumes, respectively.

Results

Between November 1997 and February 2002, 44 patients were enrolled (median age, 59 years; 59% male; stage III, 98%; median tumor size, 4 cm). Thirty-nine patients completed induction chemotherapy: 19 had a partial response, seven progressed, 15 had no response, and three were not assessable. Chemotherapy-associated toxicities were similar in the two chemotherapy groups. The incidence of grade ≥ 3 RT-induced toxicity was 1/13, 2/14, and 4/12 at 73.6, 80, and 86.4 Gy, respectively, thus defining the maximum tolerated dose at ≈80 Gy. Toxicities were in both lung and esophagus and were similar in the two chemotherapy arms. With a median followup of 34 months in the survivors, the actuarial 2-year survival was 47%, the median survival was 18 months. Fifteen patients had tumor relapse: 5 local failures in the high-dose volume, 2 regional failures outside of the high-dose volume, and 8 distant metastases.

Conclusion

High-dose conformal twice-daily radiation therapy to approximately 80 Gy appears tolerable in well-selected patients with unresectable lung cancer following either C/T or C/N. Dose-limiting toxicities are mainly pulmonary and esophageal.

Chemotherapy for malignant pleural mesothelioma: past results and recent developments

This review summarises results of previously conducted clinical trials and subsequently presents data arising from all phase II-III studies on chemotherapy for malignant pleural mesothelioma (MPM) published since the last relevant overview. While response rates exceeding 30% have barely been achieved with established cytotoxic drugs in MPM therapy, novel chemotherapeutic agents and their combinations appear somewhat more promising. This applies especially to the antimetabolites, and in particular to pemetrexed which produced response rates of up to 45% in combination with platinum compounds. Raltitrexed combined with oxaliplatin has also been shown to be effective, and gemcitabine--applied as a single agent or in combination with cisplatin--as well as vinorelbine appear to improve quality of life in patients presenting with MPM. Data can now be more precisely analysed by increasingly implemented randomised studies, applying a standardised staging system, and distinguishing prognostic groups. While chemotherapy for MPM remains a challenging task, important steps have clearly been made in the past years to combat this aggressive disease. Publication of results from a phase III trial of pemetrexed with cisplatin in a peer reviewed journal may soon establish a standard of care.

Assessing quality of life during chemotherapy for pleural mesothelioma: feasibility, validity, and results of using the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire and Lung Cancer Module

PURPOSE

To assess the feasibility and validity of using the European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30) and Lung Cancer Module (QLQ-LC13) to describe health-related quality of life (HRQL) in patients with pleural mesothelioma undergoing combination chemotherapy, to identify the most impaired aspects of HRQL, and to assess the impact of chemotherapy on HRQL.

PATIENTS AND METHODS

Fifty-three patients received cisplatin on day 1 and gemcitabine on days 1, 8, and 15 of a 28-day cycle for a maximum of six cycles. HRQL was assessed using the EORTC QLQ-C30 and QLQ-LC13.

RESULTS

Compliance was 100% at baseline but subsequently decreased. At baseline, role function and social function were the most impaired domains, and the worst-rated symptoms were fatigue, dyspnea, pain, insomnia, appetite loss, and cough. Dyspnea, pain, insomnia, and cough improved with chemotherapy, although functional domains and chemotherapy-related symptoms deteriorated. Fatigue remained unchanged. Few patients reported hemoptysis. Functional domains and symptoms scales from the QLQ-C30 demonstrated predictive validity for survival. The predictive value of QLQ-LC13 pain scores was improved by combining three pain items into a single score. Dyspnea scores were correlated strongly with lung function as measured by forced vital capacity.

CONCLUSION

This study supports the validity of the EORTC QLQ-C30 and LC13 as outcome measures for trials of chemotherapy in mesothelioma. Although the most prominent symptoms reported were concordant with clinical experience, impairments in role and social function and insomnia were worse than expected. Future research should focus on how best to apply, analyze, and interpret existing, validated HRQL instruments in mesothelioma research and practice, not on the development of new ones.

Malignant pleural mesothelioma--an update

Exposure to asbestos is the most frequent, but not exclusive, cause of malignant mesothelioma. Clinical features include dyspnea, cough, nonspecific chest pain, weight loss and night sweats. Diagnosis may be complicated by histologic difficulties. Thoracoscopic techniques are proving beneficial, but no one method of imaging has proven superior, and disease staging is inconsistent. Conventional treatments such as chemotherapy, surgery, and radiotherapy have had variable impacts, although chemotherapy is useful in palliation and can improve both survival and quality of life. There is hope for new antimetabolite agents. The role of radical surgery is yet to be evaluated in a large trial. New radiotherapeutic techniques to improve local control are promising. Multimodality treatments appear to be the most successful for management of potentially resectable disease. It is likely that biological markers will improve accuracy in staging and prognosis. With new treatments based on better understanding of the biology of the disease, there is cautious optimism for the future for patients with malignant pleural mesothelioma.