Carboplatin in malignant mesothelioma: a phase II study of the Cancer and Leukemia Group B

Effects of chemogenetic virus injection and clozapine administration in spinal cord injury

Neuromodulation therapy using chemogenetic stimulation has shown potential in enhancing motor recovery and neuroregeneration following spinal cord injury (SCI). These therapeutic benefits are hypothesized to result from the promotion of neuroplasticity, particularly when administered during the acute phase of injury. In this study, we investigated the effects of chemogenetic stimulation using Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) in conjunction with clozapine, a ligand for receptor activation. DREADDs enable targeted, reversible neuromodulation, facilitating the histological characterization of engineered neurons. We utilized these receptors to modulate G-protein-coupled receptor (GPCR) signaling pathways, leading to the activation or inhibition of intracellular signaling. The objective was to determine whether the administration of DREADDs and clozapine (0.1 ​mg/kg) could enhance motor function and neuronal recovery, particularly when applied during the acute phase of SCI. Weekly behavioral assessments demonstrated significant improvements in motor skills and neuronal regeneration in treated animals compared to controls, with the most pronounced effects observed when stimulation was initiated early after injury. These enhancements in neuroplasticity were reflected in improved ladder rung test scores and Basso, Beattie, and Bresnahan (BBB) scale results in DREADDs-treated rats. Histological analyses, including immunohistochemistry (IHC) staining, Western blotting, and quantitative reverse transcription PCR (qRT-PCR), confirmed that the treatment group exhibited a higher density of neurons, increased signaling protein expression, and reduced inflammatory markers. These findings suggest that chemogenetic stimulation, particularly when administered during the acute phase, effectively promotes neuroregeneration and motor recovery. Future research should focus on assessing the long-term safety and efficacy of chemogenetic virus injection and clozapine administration, with an emphasis on the timing of intervention.

Response to Chemotherapy of Brain Metastases from Malignant Pleural Mesothelioma

Brain metastases represent an uncommon complication in malignant pleural mesothelioma. A 55-year-old male suffering from malignant mesothelioma and pretreated with intracavitary chemotherapy and radiotherapy was submitted to systemic chemotherapy including lomustine, carboplatin, vinorelbine, fluorouracil and folates after diagnosis of bilateral cerebral deposits. The patient had an impressive response to chemotherapy, with complete regression of related symptoms. This case report represents the first on response to chemotherapy of brain metastases from mesothelioma. It points out that chemotherapy should be further explored in this subset of patients.

Validation of Progression-Free Survival as a Surrogate Endpoint for Overall Survival in Malignant Mesothelioma: Analysis of Cancer and Leukemia Group B and North Central Cancer Treatment Group (Alliance) Trials

PURPOSE

The aim of this study was to investigate whether progression-free survival (PFS) can be considered a surrogate endpoint for overall survival (OS) in malignant mesothelioma.

MATERIALS AND METHODS

Individual data were collected from 15 Cancer and Leukemia Group B (615 patients) and 2 North Central Cancer Treatment Group (101 patients) phase II trials. The effects of 5 risk factors for OS and PFS, including age, histology, performance status (PS), white blood cell count, and European Organisation for Research and Treatment of Cancer (EORTC) risk score, were used in the analysis. Individual-level surrogacy was assessed by Kendall's tau through a Clayton bivariate Copula survival (CBCS) model. Summary-level surrogacy was evaluated via the association between logarithms of the hazard ratio (log HR)-log HR_OS and log HR_PFS-measured in R² from a weighted least-square (WLS) regression model and the CBCS model.

RESULTS

The median PFS for all patients was 3.0 months (95% confidence interval [CI], 2.8-3.5 months) and the median OS was 7.2 months (95% CI, 6.5-8.0 months). Moderate correlations between PFS and OS were observed across all risk factors at the individual level, with Kendall's tau ranging from 0.46 to 0.47. The summary-level surrogacy varied among risk factors. The Copula R² ranged from 0.51 for PS to 0.78 for histology. The WLS R² ranged from 0.26 for EORTC and PS to 0.67 for age.

CONCLUSIONS

The analyses demonstrated low to moderate individual-level surrogacy between PFS and OS. At the summary level, the surrogacy between PFS and OS varied significantly across different risk factors. With a short postprogression survival and a moderate correlation between PFS and OS, there is no evidence that PFS is a valid surrogate endpoint for OS in malignant mesothelioma. The Oncologist 2017;22:189-198Implications for Practice: For better disease management and for more efficient clinical trial designs, it is important to know if progression-free survival (PFS) is a good surrogate endpoint for overall survival in malignant mesothelioma. With a relatively large database of 17 phase II trials and 716 patients from Cancer and Leukemia Group B and North Central Cancer Treatment Group, we conducted statistical analyses and found that there is no evidence to suggest that PFS is a valid surrogate endpoint for OS for malignant mesothelioma. Future research work is needed to find alternative surrogate endpoints for OS.

Vinflunine: review of a new vinca alkaloid and its potential role in oncology

Objective: To review the pharmacology, pharmacokinetics, in vitro and in vivo efficacy, and safety profile of vinflunine in the treatment of various solid tumors.

Data sources: A literature search was conducted using keywords included vinflunine, vinca alkaloid, Javlor, and solid tumor in PubMed/MEDLINE (1950—January 2009) and International Pharmaceutical Abstracts (1950—January 2009). Study selection and data extraction: Published studies, posters, and meeting abstracts evaluating the in vitro and in vivo efficacy of vinflunine were reviewed.

Data synthesis: Vinflunine is the newest member of the vinca alkaloid family. It has the weakest affinity to tubulins, but is shown to have unique receptor-independent antiangiogenesis, and antimetastasis properties. After administration, it is distributed extensively into tissues, metabolized via the CYP3A4 system, and eventually excreted in urine and feces. Phase II/III trials reported activities of vinflunine in advanced stage nonsmall-cell lung cancer, metastatic breast cancer, metastatic renal cell carcinoma, transitional cell carcinomas of the urothelium, small-cell lung cancer, and malignant pleural mesothelioma as monotherapy and in combination with other chemotherapy agents. More ongoing trials are evaluating its use in other solid tumors and in combination regimens. The most common adverse events in these trials were hematological (anemia and neutropenia), constipation, fatigue, abdominal pain, and myalgia.

Conclusions: Vinflunine is a new vinca alkaloid for the treatment of advanced staged solid tumors. Available data showed promising activities in various malignancies. Further studies are needed to further define vinflunine’s role in oncology.

Malignant pleural mesothelioma: medical treatment update

Malignant pleural mesothelioma (MPM) is a disease usually unaffected by current therapeutic strategies, but for the majority of patients, the use of systemic chemotherapeutic drugs remains the only therapeutic option available. During the past 15-20 years, many phase II and a few phase III clinical trials have studied a large variety of drugs such as anthracyclines, alkylating agents, platinum compounds, taxanes, vinka alkaloids, and antifolates as single agents and in combination, with the aim to increase responses and survival. The combination of pemetrexed and cisplatin tested in the largest phase III randomized trial of malignant pleural mesothelioma ever conducted has become the current standard of care. New targeted therapeutic approaches with a variety of anti-growth factor drugs are currently undergoing investigation worldwide.

Treatment of malignant pleural mesothelioma with carboplatin, liposomized doxorubicin, and gemcitabine: a phase II study

BACKGROUND

Malignant pleural mesothelioma has a poor prognosis and there is limited effect of treatment. The Nordic Mesothelioma groups decided in the year 2000 to investigate a combination of liposomized doxorubicin, carboplatin, and gemcitabine for this disease in a phase II study.

METHODS

From January 2001, to December 2003, 173 evaluable patients with biopsy-verified malignant mesothelioma were included. Two patients were lost to follow-up, but all the others were followed for at least 4 years or until death.

RESULTS

Toxicity was fairly low. There were 56 responses (32.4%), of which 2 were complete; the median time to progression was 8.6 months, and the median overall survival was 13 months. Some patients had their responses 4 to 6 months after last treatment. For 116 patients with epitheloid subtype, median survival was 17 months. A subgroup of these patients with good performance status, early stage, and age 70 years or less, showed a median survival of 22 months.

CONCLUSION

The treatment yields good results with a high number of responses and long survival, and a low toxicity. The long survival of the epitheloid subgroup with good prognostic factors is as good as or even better than some studies on "radical" surgery or multimodal treatment, underlining the need of randomized studies to evaluate such treatment options.

Gemcitabine and vinorelbine in pemetrexed-pretreated patients with malignant pleural mesothelioma

BACKGROUND

Pemetrexed-cisplatin chemotherapy is the standard of care in the first-line treatment of unresectable malignant pleural mesothelioma (MPM). Second-line cytotoxic therapy is considered for a growing group of patients, but the optimal treatment has not been defined to date. Gemcitabine and vinorelbine have shown activity in the first-line setting. The objective of this study was to evaluate the activity and toxicity of the gemcitabine-vinorelbine combination in pemetrexed-pretreated patients with MPM.

METHODS

From January 2004 to September 2006, 30 consecutive patients who were pretreated with pemetrexed with or without a platinum-derivative were enrolled. Gemcitabine 1000 mg/m(2) and vinorelbine 25 mg/m(2) were administered intravenously on Days 1 and 8 every 3 weeks. Treatment was repeated for a maximum of 6 cycles or until progression or unacceptable toxicity.

RESULTS

A partial response was observed in 3 patients (10%; 95% confidence interval [CI], 2.1-26.5%), and 10 patients (33.3%; 95% CI, 17.3-52.8%) had stable disease after treatment. Overall, 13 patients (43.3%; 95% CI, 25.5-62.6%) achieved disease control. The median time to progression was 2.8 months (range, 0.6-12.1 months), and the median survival was 10.9 months (range, 0.8-25.3 months). Hematologic toxicity was acceptable, with grade 3 or 4 neutropenia occurring in 11% of patients and thrombocytopenia occurring in 4% of patients; no case of febrile neutropenia was observed. Nonhematologic toxicity generally was mild.

CONCLUSIONS

The gemcitabine and vinorelbine combination was moderately active and had an acceptable toxicity profile in pemetrexed-pretreated patients with MPM. The role of second-line treatment in MPM needs to be evaluated in prospective trials in large series of patients who are stratified according to previous treatment and prognostic factors.

Emerging drugs for mesothelioma

Malignant mesothelioma is an aggressive, but relatively rare, malignancy, affecting the pleura and peritoneum. The prognosis for malignant pleural mesothelioma (MPM) is poor, with median survival in the range of 8-14 months, depending on stage and presentation of disease. Long-term results of available treatments are disappointing not only in terms of prognosis, but also of local control of the disease. Therefore, relief of symptoms and improvement of quality of life parameters are the short-term goals of therapy. In advanced disease not amenable to any local approach, such as surgery, combination chemotherapy represents the current standard of care. At present, the regimen of cisplatin/pemetrexed is the medical treatment of choice. This review summarizes standard chemotherapy options and focuses on the molecular basis of the newest biologically targeted therapies to be implemented in the near future, in the management of MPM.

The cancer and leukemia group B respiratory committee

The Cancer and Leukemia Group B Respiratory Committee has a 30-year track record of clinical investigation in patients with small-cell lung cancer and non-small-cell lung cancer (NSCLC) and mesothelioma. The most widely recognized contributions of the Committee include the early confirmation of the role of concurrent chemoradiotherapy in LD-SCLC, the effect of combination chemotherapy followed by radiation in stage III NSCLC, the introduction of third-generation agents into concurrent chemoradiation for stage III disease, the prospective demonstration of the benefit of treating older (70 years old) and poorer performance status (performance status = 2) patients with first-line combinations for stage IV disease, and the development of the "Herndon prognostic index" to normalize patient characteristics and outcomes in sequential phase II trials of new agents in patients with mesothelioma. Many other contributions have also emerged from the Committee's clinical trials and correlative science programs. We look forward to making additional critical contributions during future decades of Cancer and Leukemia Group B Respiratory Committee research.

Phase II study of pemetrexed plus carboplatin in malignant pleural mesothelioma

PURPOSE

This multicenter, phase II clinical study was conducted to evaluate the activity of the combination of pemetrexed and carboplatin in patients with malignant pleural mesothelioma (MPM).

PATIENTS AND METHODS

Chemotherapy-naive patients with measurable disease and adequate organ function, who were not eligible for curative surgery, received pemetrexed 500 mg/m2 and carboplatin area under the plasma concentration-time curve of 5 mg/mL/min, administered intravenously every 21 days. All patients received folic acid and vitamin B12 supplementation. Pemetrexed was provided within the Expanded Access Program.

RESULTS

A total of 102 patients were enrolled. An objective response was achieved in 19 patients (two complete and 17 partial responses), for a response rate of 18.6% (95% CI, 11.6% to 27.5%). Forty-eight patients (47.0%; 95% CI, 37.1% to 57.2%) had stable disease after treatment. Overall, 67 patients (65.7%) achieved disease control (95% CI, 55.6% to 74.8%). Median time to progression was 6.5 months; median overall survival time was 12.7 months. Compliance to treatment was excellent, with a relative dose-intensity of 97% for pemetrexed and 98% for carboplatin. Toxicity was mild, with grade 3 or 4 neutropenia occurring in 9.7% of total cycles and grade 3 or 4 anemia occurring in 3.5% of total cycles. Nonhematologic toxicity was negligible.

CONCLUSION

Treatment with pemetrexed and carboplatin was active and well tolerated in patients with MPM. Disease control rate, time to disease progression, and overall survival were similar to the results achieved with the standard regimen of pemetrexed and cisplatin, suggesting that the carboplatin combination could be an alternative option for these patients.

An overview of chemotherapy for mesothelioma

Mesothelioma is an extraordinarily challenging disease to treat. While numerous clinical trials testing various chemotherapeutic agents have been conducted over the last several decades, only recently have larger studies proven the efficacy of newer chemotherapy regimens. This article reviews the data regarding specific classes of chemotherapeutic agents. The role of treatment in various disease settings and the difficulty in assessing the benefit of that therapy is discussed. Finally, an update is provided on novel therapeutics being testing in mesothelioma.

Cisplatin and gemcitabine in malignant pleural mesothelioma: a phase II study

Aims of this study were to evaluate the activity and toxicity of gemcitabine and cisplatin combination in malignant pleural mesothelioma (MPM). Patients with histologically proven MPM, < 75 years of age, Eastern Cooperative Oncology Group (ECOG) performance status (PS) < or = 2, and measurable MPM were eligible. Patients received gemcitabine 1250 mg/m intravenously on days 1 and 8 and cisplatin 75 mg/m on day 2, every 21 days, for a maximum of 6 cycles. From May 1999 to May 2001, 35 chemonaive patients (median age, 61 years) were enrolled. A total of 177 cycles were administered (median 5 cycles; range 1 to 6). One patient was not evaluable for response and toxicity. Nine (26%) patients had partial responses, 11 (32%) patients had progressive disease, and 14 (41%) stable disease. Median survival for all patients was 13 months. Median progression-free survival was 8 months. Grade 3 (World Health Organization) nausea and vomiting occurred in 35% of patients. Grade 3/4 anemia, grade 3/4 thrombocythemia, and grade 3/4 neutropenia were assessed in 24%, 52%, and 61% of patients, respectively. All other side effects were mild. In conclusion, gemcitabine-cisplatin combination seems to be moderately active in MPM. Furthermore, at this dose and schedule, the toxicity profile could be acceptable.

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.

Chemotherapy options and new advances in malignant pleural mesothelioma

Malignant pleural mesothelioma continues to be a challenging clinical problem. While traditionally, chemotherapy has been thought to be of only modest benefit to patients with this disease, novel antineoplastic agents and combination regimens incorporating these agents are gradually changing this perception. Early attempts at treatment and palliation with single agents such as doxorubicin met with low response rates and little clinical benefit. However, the recently reported clinical benefits of pemetrexed and raltitrexed in combination with cisplatin are changing the perception about the ability of chemotherapy to affect the natural history of the disease. Other combinations, including cisplatin and gemcitabine, have also shown encouraging response rates and clinical activity. Single-agent therapy with vinorelbine may provide useful palliation with low toxicity. Targeted agents developed through increased understanding of the biology of the disease, used alone or as part of multimodal therapy, may provide major clinical gains in the next few years.

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.

Malignant Pleural Mesothelioma

The diagnosis and management of malignant pleural mesothelioma are major challenges that often frustrate both patient and clinician alike. Occupational asbestos exposure to crocidolite or amosite forms of the fiber is the most important known risk factor in North America and Western Europe. Other mineral fibers such as erionite, a naturally occurring fibrous zeolite crystal, are associated with mesothelioma in volcanic tuffs of the Cappadocia region of central Anatolia in Turkey. In addition, other possible factors such as the presence of simian virus 40 and genetic susceptibility have been associated recently with the development of mesothelioma in animal models. These latter findings are increasing our understanding of this disease. In addition, the discovery of elevated levels of various markers such as folic acid receptor alpha, cyclooxygenase 2, and multidrug resistance proteins 1 and 2 in mesothelioma tissue have opened up new areas of potential diagnostic and therapeutic importance. However, traditional treatment modalities--surgery, radiotherapy, and chemotherapy--have evolved slowly, and few gains in therapeutic efficacy have occurred. Recently, however, continuing research efforts have led to novel treatment strategies that are changing the way clinicians view a disease that has traditionally been managed with almost universal therapeutic nihilism. This review explores our current knowledge of this disease and presents current and novel therapeutic strategies.

Experimental therapy of malignant mesothelioma: new perspectives from anti-angiogenic treatments

We reviewed the published literature of clinical studies in malignant mesothelioma (MM), including phase II as well as older single-agent and combination chemotherapy trials with more than 15 patients. While response rates exceeding 30% have been achieved with established cytotoxic drugs in MM therapy, novel chemotherapeutic agents and their combinations appear more promising. This applies especially to the anti-metabolites (i.e. pemetrexed) that produced response rates of up to 45% in combination with platinum compounds. Moreover, agents targeting novel proliferative and survival pathways in MM are developed to improve treatment outcomes. Here, we focused on the role of several angiogenic growth factors in MM biology and the data of MM-oriented studies on angiostatic agents tested in a phase I-II trial. It seems likely that no single treatment modality will be effective by itself. Studies that use combinations of the newer agents, including angiostatic drugs, with chemotherapy, should be conducted.

Novel Combinations Using Pemetrexed in Malignant Mesothelioma

Malignant mesothelioma is an uncommon malignancy that is locally invasive and rapidly fatal. The majority of patients with mesothelioma are not candidates for curative surgical resection. Chemotherapy has yielded only modest results in these patients. Pemetrexed is a multitargeted antifolate that is being evaluated in many tumor types. Recent single-agent data and data in combination with cisplatin have suggested that pemetrexed has therapeutic benefits in patients with malignant mesothelioma. This article summarizes the data regarding pemetrexed in the treatment of malignant mesothelioma and the potential novel combinations involving the drug that may be used in the future for the treatment of the disease.

Carboplatin and gemcitabine chemotherapy for malignant pleural mesothelioma: a phase II study of the GSTPV

This study describes the therapeutic effect of carboplatin and gemcitabine in combination for malignant pleural mesothelioma (MPM). Twenty patients (14 males and 6 females) with a median age of 53 years entered the study. These patients had histologically proven MPM with no previous chemo- and/or radiotherapy and malignancies. A total of 91 cycles of treatment were administered to 20 patients with a median of 4 cycles per patient. A partial response was observed in 4 out of 20 patients (20%, 95% confidence interval: 6-43%). No complete responses were observed. Only 5 patients (25%) had progressive disease. The response duration ranged form 4+ and 21 months.

Chemotherapy for Malignant Pleural Mesothelioma

Malignant pleural mesothelioma is an aggressive malignancy with no known single curative modality. Most patients are candidates for chemotherapy at some point in their treatment, but no standard regimen has been established. Several phase II single-agent and combination chemotherapy studies have been performed over the past 2 decades. Although the true impact of chemotherapy in mesothelioma remains to be determined, agents with consistent antitumor activity include doxorubicin, platinum agents, and antimetabolites. Combination chemotherapy is associated with higher response rates, but not necessarily longer median survivals. Large randomized trials, which are currently ongoing or have been performed in the past few years, will yield important answers in regard to the role of chemotherapy and the efficacy of various single and combination chemotherapy agents. Furthermore, the biologic and genetic studies of mesothelioma have identified several receptor tyrosine kinases that are aberrantly expressed in these tumors. Orally available small molecule inhibitors of several receptor tyrosine kinases have been developed and are now being evaluated in clinical trials.

Gemcitabine combined with carboplatin in patients with malignant pleural mesothelioma: a multicentric phase II study

BACKGROUND

Malignant pleural mesothelioma (MPM) is increasing rapidly worldwide. Currently, pemetrexed plus cisplatin chemotherapy showed a survival advantage versus cisplatin alone. No impact on patient survival of surgery, radiotherapy, or their combination has been demonstrated.

METHODS

Eight centers in northeastern Italy participated in a Phase II multicenter study. Chemotherapy was comprised of carboplatin area under the concentration-time curve 5 on Day 1 and gemcitabine 1000 mg/m(2) on Days 1, 8, and 15. This cycle was repeated every 4 weeks.

RESULTS

Between July 1996 and September 2000, 50 patients were treated. Of the sample, 68% were males, 88% had a Eastern Cooperative Oncology Group performance status score of 0-1, 56% had Stage I-II disease, 68% had epithelioid histology, and 62% had no previous treatments. The delivered dose intensity of gemcitabine was 617 mg/m(2) per week, which was 82% of the planned dose (750 mg/m(2) per week). For carboplatin, the delivered dose intensity was 80 mg/m(2) per week. Overall, 44% of 15th day doses were omitted or reduced. Twenty-six percent of the patients had partial responses (95% confidence interval: 15-40%) and 24% had disease progression. None of the patients had complete responses. The median response duration was 55 weeks (range, 13-113 weeks). Patients had good clinical benefit. For example, 46% had improved dyspnea, 40% improved in weight, and 26% experienced pain reduction. Patients developed Grade 3-4 leukopenia during 18 cycles (11%) of chemotherapy. Grade 3-4 thrombocytopenia occurred more frequently, i.e., there were 24 episodes (15%) among 17 patients. Grade 3 anemia developed among patients during eight cycles (5%). None of the patients developed Grade 3-4 nonhematologic toxicity. The median survival of this sample of patients was 66 weeks with 53%, 30%, and 20% of patients alive at 1, 2, and 3 years, respectively. The median progression-free survival period was 40 weeks.

CONCLUSIONS

The gemcitabine/carboplatin combination is a valid option in the treatment of MPM due to its acceptable toxicity profile, the good response rate, and the clinical benefit to patients. Minor adjustments in schedule (3-week cycles instead of 4-week cycles) would permit a more optimal treatment administration.

Chemotherapy for malignant pleural mesothelioma

This paper covers the outcome of previously conducted clinical trials on chemotherapy for malignant pleural mesothelioma and presents data from recent phase II and phase III trials. In contrast to conventional cytotoxic drugs, which have barely produced response rates exceeding 30%, recently introduced chemotherapeutic agents and their combinations promise to be more effective. Especially pemetrexed has yielded response rates of up to 45% in combination with platinum compounds. Furthermore, raltitrexed-oxaliplatin has shown promising activity and gemcitabine was found to improve quality of life in patients with malignant pleural mesothelioma when applied as a single agent or in combination with cisplatin. Based on robust phase III study results, pemetrexed-cisplatin may soon be considered with chemotherapy for this aggressive disease.

Chemotherapy for malignant pleural mesothelioma: past results and recent developments

This review summarises the results of previously conducted clinical trials, and subsequently presents data arising from all phase II-III studies on chemotherapy of 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 more promising. This applies especially to the antimetabolites, and in particular to pemetrexed that 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 the 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. The publication of pemetrexed with cisplatin phase III results in a peer-reviewed journal may soon establish a standard of care.

Activity of chemotherapy and immunotherapy on malignant mesothelioma: a systematic review of the literature with meta-analysis

The role of chemotherapy for unresectable malignant mesothelioma is unclear. The aims of the present study were to evaluate the methodological quality of published papers relative to chemotherapy or immunotherapy in malignant mesothelioma and to aggregate, for trials having a similar methodology, the response rates in order to identify the most active chemotherapeutic drugs and regimens. The literature relative to this topic, published between 1965 and June 2001 was reviewed. A methodological qualitative evaluation was performed according to the European Lung Cancer Working Party scale, specifically designed for phase II trials. A study was considered as potentially positive if the upper limit of the 95% confidence interval (CI) of the response rate was greater than 20% and positive if the lower limit of the 95% CI was > 20%. Eighty-three studies (88 treatment arms) were eligible for the systematic review. Fifty-three arms were considered as positive or potentially positive. No statistically significant difference in the methodological quality was observed between negative and positive studies. Studies were aggregated in four groups according to the presence of cisplatin and/or doxorubicin in the treatment regimen. The combination of cisplatin and doxorubicin had the highest response rate (28.5%; P < 0.001). Cisplatin was the most active single-agent regimen. Our systematic qualitative and quantitative overview of the literature suggests that the most active chemotherapeutic regimen, in term of objective response rate, is the combination of cisplatin and doxorubicin and the best single-agent is cisplatin. The combination of these two drugs can be recommended as control arm for future randomised phase III trials.

Phase I clinical and pharmacokinetic study of pemetrexed and carboplatin in patients with malignant pleural mesothelioma

PURPOSE

To determine the maximum tolerated dose (MTD) of pemetrexed and carboplatin given in combination, to derive a recommended dose for phase II studies, and to explore its efficacy. We assessed toxicities and explored the activity of the drug combination exclusively in patients with malignant pleural mesothelioma (MPM). The pharmacokinetics of both agents was investigated.

PATIENTS AND METHODS

Twenty-seven patients (23 male, four female) with MPM were treated on five escalating dose levels. Doses ranged from pemetrexed 400 mg/m(2) (as a 10-minute intravenous infusion), followed by carboplatin area under the plasma concentration-time curve (AUC) 4 mg/mL.min (as a 30-minute intravenous infusion) to pemetrexed 500 mg/m(2), carboplatin AUC 6 mg/mL.min. All patients had a World Health Organization performance status of 1. A total of 163 courses of treatment were administered (median, six; range, one to 10).

RESULTS

The main toxicity was hematologic, particularly neutropenia, although this was characteristically short-lived and caused few clinical problems. The MTD was pemetrexed 500 mg/m(2), carboplatin AUC 6, because three of the five patients treated at this dose level experienced a dose-limiting toxicity. Eight partial responses (in 25 assessable patients) were observed for a response rate of 32%. Seventy percent of patients noticed an improvement in symptoms, usually (84%) after only two courses. Median time to progression was 305 days, and median survival time was 451 days.

CONCLUSION

The MTD was pemetrexed 500 mg/m(2) and carboplatin AUC 6 mg/mL.min. The recommended phase II dose of the combination is pemetrexed 500 mg/m(2) and carboplatin AUC 5 mg/mL.min. The combination is both active and well tolerated in MPM and deserves further exploration.

Malignant mesothelioma: options for management

In the past, there has been a tendency to think of diffuse malignant pleural mesothelioma as one disease in therapeutic terms, regardless of histological type and tumor stage. This does not happen with other tumors, yet it is equally illogical and inappropriate in mesothelioma. As with other tumors, early diagnosis-while the disease is still in stage I, or even at an in situ stage-must be the goal so that therapy can be maximized, particularly if immunotherapy or gene therapy is to be used. Patients with pure epithelial mesothelioma have a better prognosis and respond better to trimodality therapy. Stage I patients who meet fitness criteria should be offered the option of radical surgery in combination with chemotherapy and radiotherapy. Further research is required to determine the optimum neoadjuvant and adjuvant modalities, particularly the timing of individual drugs, use of hyperthermia, and route of administration. The place of immunotherapy and gene therapy as adjunctive treatments also remains to be defined. For example, it may be possible to reduce tumor bulk and perhaps downstage the disease with immunotherapy before radical surgery, if treatment is started early enough. Gene therapy may have a role either preoperatively or in destroying the microscopic disease that remains after radical surgery. These and other combinations of treatment need to be tested in well-designed clinical trials, probably on a multicenter basis (to enroll a sufficient number of patients). Finding the means to improve treatment for sarcomatous and mixed histology mesothelioma remains a challenge. At present, radical surgery does not seem worthwhile for these patients when combined with currently employed chemotherapy and radiotherapy; however, chemotherapy combinations used for treating other sarcomas need to be evaluated as adjunctive therapy before radical surgery is abandoned altogether as a mode of treatment. A collaborative approach involving thoracic surgeons, basic scientists and oncologists, and physicians with experience in treating mesothelioma is essential. Despite its increasing frequency, mesothelioma is still a relatively rare tumor, so treatment should be concentrated in relatively few supraregional centers to maximize expertise and allow innovative treatment combinations to be implemented with the greatest chance of success. Evaluation of new therapeutic approaches will be achieved more rapidly if these supraregional centers collaborate in multicenter trials. The nihilistic approach of simply waiting until the mesothelioma epidemic eventually begins to decline spontaneously in 20 or 30 years is untenable in view of the hundreds of thousands of deaths that will result if no effective treatment is found.

Current therapy for malignant mesothelioma

This review briefly summarizes the results of previous systemic (chemotherapy) and local (surgery and radiotherapy) treatment attempted to date for malignant mesothelioma. The prospects for newer modalities, ie molecular and biologic therapies, are also highlighted, including results of both preclinical and early clinical research.

Malignant pleural mesothelioma: a phase II trial with docetaxel

Current cytotoxic therapy has been of limited benefit to patients with malignant pleural mesothelioma. Single agent chemotherapy has been extensively evaluated in small series of phase II clinical trials, with disappointing responses. Docetaxel, an effective taxane in the treatment of advanced breast cancer and non-small-cell lung cancer, was administered intravenously at a dose of 100 mg/m2 every 3 weeks to 30 chemotherapy naive patients with malignant pleural mesothelioma in a prospective multi-institutional phase II clinical trial. An objective response rate (partial responses) of 10% was documented. Additionally, 21% of the patients had minor responses (intention-to-treat analysis). Three patients died within 2 weeks post-first cycle of therapy, although only one patient's death was directly attributed to the investigational drug, whilst in the majority of the patients, manageable and treatable toxicities were encountered. In this phase II clinical trial, docetaxel proved to be mildly effective in the treatment of patients with malignant pleural mesothelioma.

Chemotherapy for malignant mesothelioma: from doxorubicin to vinorelbine

It has been a challenge to find effective chemotherapeutic treatments for malignant mesothelioma. Over the last several decades numerous single-drug and combination regimens have been examined, but no standard treatment with chemotherapy alone has emerged. Possible explanations for this lack of success are the heterogeneity between the different subclasses of mesothelioma and the difficulties experienced in determining responses on computed tomographic (CT) scan. This review will present the results of most chemotherapy trials. An attempt is also been made to overcome the problem of identifying the overall response rate by presenting the median survival time. Other types of response evaluation and guidelines for patient selection are warranted to properly compare chemotherapeutic treatments.

Photodynamic therapy for mesothelioma

Multiple trials of traditional cancer therapies for malignant pleural mesothelioma (including surgery, radiation therapy, and chemotherapy) have not convincingly demonstrated that any one treatment is superior to supportive care alone. Although there have been reports of long-term survivors who were treated with aggressive surgery combined with radiation and aggressive multi-agent chemotherapeutic regimens, these patient populations are highly selected and results cannot be generalized to a larger population. Despite attempts to use aggressive multimodality therapies, disease recurs in most patients. Local failure in particular is a large part of the natural history of mesothelioma, especially after surgery alone. Therefore, one of the major considerations in the development of new treatments is the inclusion of aggressive local therapies. Photodynamic therapy (PDT), a local treatment modality, is being evaluated as an adjuvant therapy to surgical resection. Clinical use of PDT requires the use of a photosensitizing agent and light of a wavelength specific to the absorption characteristics of the sensitizer in the presence of oxygen. The treatment effect of PDT is superficial, mostly because of the limited depth of light absorption in tissues. Therefore, it is theoretically an ideal treatment for tissue surfaces and body cavities after surgical debulking procedures. One theoretical advantage of PDT is that it can be used to treat the lung surface after a pleurectomy; therefore, patients may be treated with a pleurectomy rather than with an extrapleural pneumonectomy. Several studies have evaluated the efficacy of PDT in the treatment of mesothelioma. Clinical studies have not proven convincingly that the use of PDT is superior to the use of other adjuvant therapies or to surgery alone. The advent of newer photosensitizers and improved laser technology has led to a renewed interest in evaluating PDT. Additional studies are necessary to determine the role of PDT in the treatment of mesothelioma.

Acupuncture: an evidence-based review of the clinical literature

This chapter reviews the experimental literature on the effects of acupuncture treatment. The review covers the 14 medical conditions for which the National Institutes of Health Acupuncture Consensus Development Panel (NIHCDP) concluded that acupuncture either is effective (2 conditions) or may be useful (12 conditions). My conclusions partially support those of the NIHCDP. There is evidence that acupuncture is effective for the treatment of postoperative and chemotherapy-induced nausea and vomiting. Also, some data indicate that acupuncture may be useful for headache, low back pain, alcohol dependence, and paralysis resulting from stroke (4 of the 12 conditions for which the NIHCDP found that acupuncture may be useful). For most of the remaining conditions, there is little evidence that acupuncture is either effective or ineffective. It is recommended that workers in the field design double blind, sham controlled trials using adequate acupuncture treatment regimens, with specific hypotheses, and sample sizes sufficient to allow both positive and negative conclusions.

Advances in the treatment of malignant pleural mesothelioma

Malignant pleural mesothelioma is a neoplasm that is commonly fatal and for which there are no widely accepted curative approaches. Mesothelioma is unresponsive to most chemotherapy and radiotherapy regimens, and it typically recurs even after the most aggressive attempts at surgical resection. Multimodality approaches have been of some benefit in prolonging survival of very highly selected subgroups of patients, but they have had a relatively small impact on the majority of the patients diagnosed with this disease. As the incidence of pleural mesothelioma peaks in the United States and Europe over the next 10 to 20 years, new therapeutic measures will be necessary. This review will discuss the roles of chemotherapy, radiotherapy, surgery, and combined modality approaches in the treatment of pleural mesothelioma, as well as scientific advances made in the past decade that have led to the development of experimental techniques, such as photodynamic therapy, immunotherapy, and gene therapy, that are currently undergoing human clinical trials. These promising new avenues may modify the therapeutic nihilism that is rampant among clinicians dealing with mesothelioma.

High-dose paclitaxel plus G-CSF for malignant mesothelioma: CALGB phase II study 9234

BACKGROUND

New agents with activity in mesothelioma are sorely needed. The Cancer and Leukemia Group B (CALGB) therefore performed a phase II study of high-dose paclitaxel in patients with malignant mesothelioma who had no prior chemotherapy.

PATIENTS AND METHODS

Thirty-five patients accrued to this multi-institutional phase II study of paclitaxel given as a 24-hour infusion at 250 mg/m2 every three weeks plus filgrastim (G-CSF) 300 mcg subcutaneously days 3-18.

RESULTS

There were three (9%) regressions of evaluable disease. The median survival was five months (95% confidence interval (95% CI): 1.9-9.6 months), the one-year survival rate was 14% and the two-year survival rate was 6%. Toxicity was tolerable with one death from pneumonia (without neutropenia) on day 18 and a 23% rate of grade 4 granulocytopenia.

CONCLUSIONS

The level of activity seen with paclitaxel is similar to that seen in other CALGB trials of the single agents carboplatin, trimetrexate and 5-azacytidine. Future studies of of paclitaxel (at lower doses) in combination with synergistic agents could be considered.

A phase II trial of interferon alpha-2a and carboplatin in patients with advanced malignant mesothelioma

We defined the antitumor activity, toxicity, and tolerability of a combined chemoimmunotherapy approach in patients with advanced malignant mesothelioma using daily low-dose interferon alpha-2a and carboplatin given every 4 weeks. This was a phase II study of 15 patients with surgically unresectable or metastatic malignant mesothelioma. All patients had measurable or assessable disease. No prior chemotherapy or immunotherapy was allowable. Carboplatin was given at 150 mg/m2 daily on days 1-3 and interferon alpha-2a at 3 million units subcutaneously daily throughout the study. Treatment was recycled every 28 days. Therapy was continued until disease progression. Fifteen patients were assessable for toxicity and 14 for response. One partial response (7%, 95% CI, 0-20%), with a response duration of 40 weeks, was seen. Most patients had early progression of disease. Toxicity was tolerable, and grade III/IV toxicity was uncommon. The median time to progression was 14 weeks (range, 1-52 weeks). The median survival was 25 weeks (range, 8-66 weeks). The combination of low-dose interferon alpha-2a and carboplatin did not result in greater antitumor activity than that reported for single-agent carboplatin in advanced malignant mesothelioma. Although toxicity was mild, carboplatin and low-dose interferon, given at this dose and schedule, cannot be recommended for this patient group.

Factors predictive of survival among 337 patients with mesothelioma treated between 1984 and 1994 by the Cancer and Leukemia Group B

PURPOSE

To examine the individual and joint effect of various pretreatment clinical characteristics on the survival of patients with mesothelioma treated by the Cancer and Leukemia Group B (CALGB).

PATIENTS AND METHODS

Between June 1984 and September 1994, 337 patients with malignant mesothelioma and no prior chemotherapy were accrued to seven phase II studies conducted by the CALGB which screened the efficacy of 10 treatment regimens or dose levels. The eligibility criteria for all studies were virtually identical. Patient characteristics include the following: age older than 60 years (63%); male (83%); performance status (PS) of 0 or 1 (81%); chest pain (60%); definite asbestos exposure (62%); >5% weight loss (41%); and pleural involvement (94%). Median survival time (MST) for the 10 treatment regimens ranged from 3.9 to 9.8 months (overall=7.2; 95% confidence interval [CI], 6.5 to 8.3), with 1-year survival between 14% and 50% (overall=27%; 95% CI, 23 to 33%).

RESULTS

Cox survival models and exponential regression trees were used to examine the prognostic importance of pretreatment patient characteristics. Univariate analyses show that patients with poor Eastern Cooperative Oncology Group PS, chest pain, dyspnea, platelet count (PLT) >400,000/microL, weight loss, serum lactate dehydrogenase (LDH) level >500 IU/L, pleural involvement, low hemoglobin (HGB) level, high WBC count, and increasing age over 75 years have a worse prognosis. With decreasing risk ratio, multivariate Cox analyses showed that pleural involvement, LDH >500 IU/L, poor PS, chest pain, PLT >400,000/microL, nonepithelial histology, and increasing age older than 75 years jointly predict poor survival. PS was the most important prognostic split in the regression tree. Terminal nodes were amalgamated to form six distinct prognostic subgroups with MST (2-year survival) of 13.9 (38%) in 36 patients, 9.5 (21%) in 36 patients, 9.2 (10%) in 146 patients, 6.5 (3%) in 33 patients, 4.4 (0%) in 73 patients, and 1.4 (0%) in 13 patients (p<0.0001).

CONCLUSIONS

The subgroup with the best survival (MST=13.9 months) included patients with PS=0 and age younger than 49 years, and patients with PS=0, age of 49 years or older, and HGB > or =14.6. The worst survival (MST= 1.4 months) occurred for patients with PS= 1/2 and WBC > or =15.6/microL.

A review of chemotherapy trials for malignant mesothelioma

Treatment of malignant pleural mesothelioma continues to be frustrating regardless of the modality employed. Numerous trials of chemotherapeutic agents have been performed, but until recently, these studies were small and subject to inaccuracies of disease measurement. To our knowledge, no chemotherapeutic regimen has emerged as a standard of care. A review of the literature reveals that small activity against this disease has been shown by the anthracyclines, platinum compounds, and alkylating agents, whereas higher activity has been reported with the antimetabolites. The plant alkaloids have not demonstrated any activity against mesothelioma. Dose-escalated chemotherapeutic regimens may offer an advantage, whereas combination chemotherapy has not shown any benefit over single-agent therapy. Favorable responses have been reported with the administration of intrapleural biological response modifiers. Further trials and the investigation of new agents in the treatment of this disease are necessary.

Dihydro-5-azacytidine in malignant mesothelioma. A phase II trial demonstrating activity accompanied by cardiac toxicity. Cancer and Leukemia Group B

BACKGROUND

Malignant mesothelioma is a disease that is refractory to chemotherapy. Therefore, the objective of this multi-institutional, cooperative group Phase II trial was to determine the efficacy of dihydro-5-azacytidine (DHAC), a pyrimidine analogue, in the treatment of malignant mesothelioma.

METHODS

Forty-one patients with histologically confirmed malignant mesothelioma received 120-hour continuous infusions of DHAC (1,500 mg/m2/day every 21 days) until maximal response, intolerable toxicity, or disease progression.

RESULTS

One patient had a complete response, two had objective partial responses, and four had regression of evaluable disease. The overall response rate was 17%. The one complete responder remains without disease progression at 6 years. Chest pain and nausea were the most common toxicities. Supraventricular tachycardia and pericardial effusion occurred in 20% and 15% of patients, respectively. In most patients, gastrointestinal effects were manageable. There was no significant hematologic toxicity.

CONCLUSIONS

In malignant mesothelioma, a disease that is refractory to chemotherapy, dihydro-5-azacytidine has definite antitumor activity. Its modest hematologic toxicity profile favors its use in combination with other agents. Caution regarding cardiac arrhythmias and pericardial effusion is necessary.