Good symptom relief with palliative MVP (mitomycin-C, vinblastine and cisplatin) chemotherapy in malignant mesothelioma

Current chemotherapy strategies in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive malignancy with a 5-year survival rate of ~10%. Since most patients present with irresectable disease, the vast majority is treated with chemotherapy. The only registered therapy for MPM is platinum-pemetrexed doublet therapy, although only up to half of patients have clinical benefit from this palliative treatment. Of the anti-angiogenesis agents, only bevacizumab and nintedanib have shown activity with platinum-pemetrexed doublet therapy. Other anti-angiogenesis agents like thalidomide did not prolong (progression free) survival or response rate. Eventually, all patients will get a recurrence and no active second line therapy has been identified to date. The clinical benefit of (switch) maintenance therapy after first line treatment and combination strategies of different chemotherapies with angiogenesis inhibitors are currently under investigation. The major challenges are finding optimal treatment combinations and to select the adequate treatment for an individual patient. This review focusses on the current standard of chemotherapy and new systemic therapy strategies under investigation.

Chemotherapy treatment in malignant pleural mesothelioma: a difficult history

Malignant pleural mesothelioma (MPM) is a rare neoplasm that typically arises from mesothelial surfaces of the pleural cavity. Despite treatment improvements, it carries a dismal prognosis. The majority of patients either have unresectable disease or are not candidates for surgery due to medical comorbidities or old age. For such patients, chemotherapy (CT) represents the gold-standard treatment. To date, combination CT with cisplatin plus pemetrexed represents the most widely used regimen in first-line setting for patients with unresectable MPM. Other first-line options are currently available, including the use of raltitrexed instead of pemetrexed combined with platinum. In this review, we discuss the role of CT in MPM mainly focusing on the results of the trials conducted in first-line setting.

A serum mesothelin level is a prognostic indicator for patients with malignant mesothelioma in routine clinical practice

BACKGROUND

Malignant mesothelioma (MM) carries a poor prognosis and response rates to palliative chemotherapy remain low. Identifying patients with MM that are unlikely to respond to chemotherapy could prevent futile treatments and improve patient quality of life. Studies have suggested that soluble mesothelin is a potential biomarker for early diagnosis and prognosis of MM. We set out to explore the utility of serum mesothelin in routine clinical practice.

METHODS

We conducted a prospective exploratory study of serum mesothelin levels in 53 consecutive patients with MM at our institution between April 2009 and February 2011. Survival was assessed and analysed by mesothelin level as both continuous and categorical variables using Cox regression models. Differences in response rate between treatment groups were assessed by the Kruskal-Wallis Test.

RESULTS

All 53 patients, who had been given study information agreed to participate. The patients' median age was 69 (range 24-90). Median mesothelin level was 2.7 nM and this value was used to dichotomize categories: ≤2.7 nM (low) and >2.7 nM (high). The progression free survival (PFS) for low vs high mesothelin was 8.0 vs 5.1 months (HR 1.8, p-0.058). When mesothelin was accessed as a continuous variable for PFS the HR was 1.03 (95% CI: 1.01-1.06; p=0.013). The overall survival (OS) for low vs high mesothelin was 17.2 vs 11.3 months (HR 1.9, p=0.088). When mesothelin was assessed as a continuous variable for OS the HR was 1.02 (95% CI: 0.99 - 1.04; p=0.073). Thirty patients received chemotherapy of which 18 had a pre-chemotherapy serum mesothelin level. In these 18 patients, the pre-chemotherapy mesothelin level did not correlate with response.

CONCLUSIONS

A single random sample provides information about patient prognosis but does not predict treatment response. We suggest further prospective validation of mesothelin testing as a prognostic biomarker.

Malignant mesothelioma

Malignant mesothelioma is a fatal asbestos-associated malignancy originating from the lining cells (mesothelium) of the pleural and peritoneal cavities, as well as the pericardium and the tunica vaginalis. The exact prevalence is unknown but it is estimated that mesotheliomas represent less than 1% of all cancers. Its incidence is increasing, with an expected peak in the next 10–20 years. Pleural malignant mesothelioma is the most common form of mesothelioma. Typical presenting features are those of chest pain and dyspnoea. Breathlessness due to a pleural effusion without chest pain is reported in about 30% of patients. A chest wall mass, weight loss, sweating, abdominal pain and ascites (due to peritoneal involvement) are less common presentations. Mesothelioma is directly attributable to occupational asbestos exposure with a history of exposure in over 90% of cases. There is also evidence that mesothelioma may result from both para-occupational exposure and non-occupational "environmental" exposure. Idiopathic or spontaneous mesothelioma can also occur in the absence of any exposure to asbestos, with a spontaneous rate in humans of around one per million. A combination of accurate exposure history, along with examination radiology and pathology are essential to make the diagnosis. Distinguishing malignant from benign pleural disease can be challenging. The most helpful CT findings suggesting malignant pleural disease are 1) a circumferential pleural rind, 2) nodular pleural thickening, 3) pleural thickening of > 1 cm and 4) mediastinal pleural involvement. Involvement of a multidisciplinary team is recommended to ensure prompt and appropriate management, using a framework of radiotherapy, chemotherapy, surgery and symptom palliation with end of life care. Compensation issues must also be considered. Life expectancy in malignant mesothelioma is poor, with a median survival of about one year following diagnosis.

Active symptom control with or without chemotherapy in the treatment of patients with malignant pleural mesothelioma (MS01): a multicentre randomised trial

BACKGROUND

Malignant pleural mesothelioma is almost always fatal, and few treatment options are available. Although active symptom control (ASC) has been recommended for the management of this disease, no consensus exists for the role of chemotherapy. We investigated whether the addition of chemotherapy to ASC improved survival and quality of life.

METHODS

409 patients with malignant pleural mesothelioma, from 76 centres in the UK and two in Australia, were randomly assigned to ASC alone (treatment could include steroids, analgesic drugs, bronchodilators, palliative radiotherapy [n=136]); to ASC plus MVP (four cycles of mitomycin 6 mg/m2, vinblastine 6 mg/m2, and cisplatin 50 mg/m2 every 3 weeks [n=137]); or to ASC plus vinorelbine (one injection of vinorelbine 30 mg/m2 every week for 12 weeks [n=136]). Randomisation was done by minimisation, with stratification for WHO performance status, histology, and centre. Follow-up was every 3 weeks to 21 weeks after randomisation, and every 8 weeks thereafter. Because of slow accrual, the two chemotherapy groups were combined and compared with ASC alone for the primary outcome of overall survival. Analysis was by intention to treat. This study is registered, number ISRCTN54469112.

FINDINGS

At the time of analysis, 393 (96%) patients had died (ASC 132 [97%], ASC plus MVP 132 [96%], ASC plus vinorelbine 129 [95%]). Compared with ASC alone, we noted a small, non-significant survival benefit for ASC plus chemotherapy (hazard ratio [HR] 0.89 [95% CI 0.72-1.10]; p=0.29). Median survival was 7.6 months in the ASC alone group and 8.5 months in the ASC plus chemotherapy group. Exploratory analyses suggested a survival advantage for ASC plus vinorelbine compared with ASC alone (HR 0.80 [0.63-1.02]; p=0.08), with a median survival of 9.5 months. There was no evidence of a survival benefit with ASC plus MVP (HR 0.99 [0.78-1.27]; p=0.95). We observed no between-group differences in four predefined quality-of-life subscales (physical functioning, pain, dyspnoea, and global health status) at any of the assessments in the first 6 months.

INTERPRETATION

The addition of chemotherapy to ASC offers no significant benefits in terms of overall survival or quality of life. However, exploratory analyses suggested that vinorelbine merits further investigation.

Cost-effectiveness of pemetrexed plus cisplatin: malignant pleural mesothelioma treatment in UK clinical practice

OBJECTIVES

Findings from the largest randomized phase III trial in patients with unresectable malignant pleural mesothelioma (EMPHACIS study; n = 448) were used to examine the cost-effectiveness of pemetrexed plus cisplatin therapy versus cisplatin monotherapy in patients with the disease. The cost-effectiveness of pemetrexed/cisplatin versus alternative treatments was also examined.

METHODS

Two cost-effectiveness analyses were designed to model best survival outcome over time for a number of patient cohorts. First, trial-based patient-level data were utilized and resource use was costed for the study arm and comparator. A second cost-effectiveness analysis then compared the mean costs and outcomes associated with pemetrexed/cisplatin with the most commonly used (unlicensed) regimens in the United Kingdom-mitomycin-C, vinblastine, and cisplatin (MVP); vinorelbine; and active symptom control-using trial-based data and data extrapolated from a review of the literature.

RESULTS

The total pemetrexed/cisplatin cost per patient varied between pound8779 and pound9020 for all cohorts studied in model 1. Average life-years gained per patient were between 0.20 and 0.28. Quality-adjusted life-years, based on mean and median survival, ranged from 0.13 to 0.31. Incremental cost per life-year gained and quality-adjusted life-year ratios, using both mean and median survival, ranged from pound20,475 to pound68,598. The second cost-effectiveness analysis resulted in ratios ranging from pound14,595 to pound32,066.

CONCLUSIONS

Pemetrexed/cisplatin demonstrated acceptable cost-effectiveness when compared with cisplatin monotherapy and alternative treatments commonly used in UK clinical practice.

The role of radiotherapy in the treatment of malignant pleural mesothelioma

Radiation therapy for the treatment of malignant pleural mesothelioma has historically been limited by its efficacy. However, the increasing incidence of this tumour and the emergence of new technologies present a number of opportunities and challenges for this treatment modality. Radiotherapy is used to palliate mesothelioma patients with chest wall pain. Responses of over 60% have been seen, although the duration of response is often disappointing. The optimum dose has not been shown and many of the previous studies were small retrospective studies. An improved response has been seen in several studies where hyperthermia was added to radiotherapy. However, further investigation of this technique, which is not widely available, is required. There has not been any comparison of radiotherapy with chemotherapy in the palliation of patients with malignant pleural mesothelioma. Prophylactic chest wall radiotherapy to intervention sites successfully reduces the incidence of malignant seeding along the intervention tracts. However, the optimum dose and timing of treatment are not clear. There is no role for radical radiotherapy alone, but the role of radiotherapy as part of multimodality therapy is discussed. There have been studies of intensity-modulated radiotherapy as part of multimodality therapy and this technique needs to be evaluated further.

Pemetrexed disodium in combination with cisplatin versus other cytotoxic agents or supportive care for the treatment of malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is a highly aggressive malignancy whose incidence is expected to increase in the United Kingdom, Western Europe, and Australia over the next 20 years as a result of occupational exposure to asbestos fibres. Surgery is feasible in only a small proportion of cases, and radiotherapy and cytotoxic chemotherapy are used in palliation. Pemetrexed is the first and only chemotherapy agent that has been granted a marketing approval for use in combination with cisplatin for the treatment of chemo-naïve patients with unresectable MPM.

OBJECTIVES

To examine evidence on the clinical effectiveness of pemetrexed disodium used in combination with cisplatin for the treatment of unresectable malignant pleural mesothelioma in chemotherapy naïve patients compared with other cytotoxic agents used alone or in combination, or supportive care.

SEARCH STRATEGY

CENTRAL (Issue 2, 2005), EMBASE (1980-2005), MEDLINE (1980-2005), HTA database (1990-2005), Web of Knowledge (1990-2005) and handsearching (including reference lists of retrieved articles and the pharmaceutical company submission to to NICE), up to October 2005.

SELECTION CRITERIA

Randomised Controlled Trials (RCTs) where the use of pemetrexed disodium in combination with cisplatin is compared with other cytotoxic agents, or supportive care for the treatment of malignant pleural mesothelioma (or non-RCTs, in the absence of RCT data ).

DATA COLLECTION AND ANALYSIS

Outcomes included overall survival, tumour response, progression-free survival, toxicity and quality of life. Data extraction and quality assessment of included trials was completed independently. Trial data and quality assessment were tabulated and presented narratively.

MAIN RESULTS

One RCT involving 448 patients and comparing pemetrexed plus cisplatin versus cisplatin alone for the treatment of unresectable malignant mesothelioma was included in the review. In the intention-to-treat study population, the median survival was statistically significantly longer in the combination arm of pemetrexed plus cisplatin when compared with the cisplatin alone arm. (12.1 and 9.3 months, respectively, p=0.002). The incidence of grade 3/4 toxicities was higher in the combination arm compared with the cisplatin alone arm.

AUTHORS' CONCLUSIONS

Pemetrexed disodium in combination with cisplatin and with folic acid and vitamin B(12 )supplementation may improve survival when used in combination with cisplatin in good performance status patients. Further studies including patients with poor performance status are needed in order to generalise the treatment findings. Further studies are also needed into the optimum chemotherapy, and a clear definition of what constitutes best supportive care.

Metaanalysis of the correlation between radiographic tumor response and patient-reported outcomes

BACKGROUND

The primary aim of the current study was to determine whether radiographic tumor response is associated with patient-reported outcomes such as symptom response or health-related quality of life.

METHODS

A metaanalysis was conducted of 21 available studies from 1995-2003 that provided data sufficient for examining the association between tumor response and patient-reported outcomes, including symptom response and health-related quality of life. A second aim was to examine the influence of possible moderating study variables on effect size variation.

RESULTS

As hypothesized, patient-reported outcome improvement rates were most frequently associated with patients classified as a complete or partial response (CR/PR), followed by those with stable disease (SD) and progressive disease (PD). Moderate effect sizes were observed between the CR/PR and SD (effect size of 0.35) and CR/PR and PD categories (effect size of 0.43). A weak effect size was found between SD and PD (effect size of 0.16), raising concern over the meaningfulness of the SD category. No significant correlations were found between effect size and patient or study characteristics. Significant associations existed between treatment duration and age, study duration, survival, and symptom response rates, especially among PD patients.

CONCLUSION

Despite significant study-to-study heterogeneity, an important association exists in the correlation between tumor response and formal measures of change in patient-reported outcomes. A better understanding of this relation would be enhanced if future reports included estimates of effect size in patient-reported outcome change by tumor response category. Practical implications, limitations, and directions for future research are provided.

A randomised trial in malignant mesothelioma (M) of early (E) versus delayed (D) chemotherapy in symptomatically stable patients: the MED trial

BACKGROUND

Prior phase II trials have demonstrated the therapeutic activity of cytotoxic chemotherapy in mesothelioma. Currently there are few randomised data assessing the role of chemotherapy versus best supportive care (BSC) in the management of patients with stable symptoms after control of any pleural effusion. A policy of observation is often adopted over initial use of chemotherapy. In this prospective randomised trial we assess the use of early versus delayed cytotoxic therapy. The study opened in 1998, and closed in view of a competing national study (MSO 1) in 2003.

METHODS

Eligible patients had a performance status<or=2, life expectancy>3 months and had stable symptoms for at least 4 weeks prior to randomisation. Patients were randomised to receive immediate chemotherapy or initial BSC with the addition of chemotherapy at time of symptomatic progression. All patients received the same platinum-based chemotherapy regimen, MVP [mitomycin C 8 mg/m2 cycles 1, 2, 4 and 6, vinblastine 6 mg/m2, maximum 10 mg, and cisplatin 50 mg/m2 (or carboplatin AUC 5)], every 3 weeks for up to six cycles.

RESULTS

A total of 43 patients were recruited, of which 21 were randomised to the early treatment group and 22 to the delayed treatment group. The median ages were 59 years (range 50-78) and 67 years (range 48-75), respectively (P=0.1); other baseline parameters were well matched between the two groups. All 21 patients in the early group received chemotherapy versus 17 patients in the delayed group. Median time to symptomatic progression was 25 weeks in the early group compared with 11 weeks for the delayed group (P=0.1). Median survival was 14 months (1-year survival 66%) for the early group compared with 10 months (1-year survival 36%) for the delayed group (P=0.1). Quality of life was in general better maintained for early treatment and the health resources use was similar in both arms.

CONCLUSIONS

In this patient group, presenting with stable symptoms after control of pleural effusion, the early use of chemotherapy provided an extended period of symptom control, and in this small trial a trend to survival advantage.

Prognostic Factors for Mesothelioma

Our understanding of malignant mesothelioma has increased rapidly in the last 5 years. The prognosis remains poor for most patients, however. Radical surgery is inappropriate for most, and palliative chemotherapy can be toxic if used without care. Patient selection is crucial, and prognostic factors allow us to predict which patients are likely to benefit from intensive treatment. Longer survival is associated with epithelioid histology, earlier stage, female gender, left-sided primary, nonexposure to asbestos, no history of smoking, and a lack of symptoms at presentation. Numerous genes of significance are identified and many have been shown to correlate with clinical outcome. Molecular data will provide prognostication of exceptional accuracy, biologic insights, and targets for improved treatment.

Prognostic factors in mesothelioma

Prognostic factors can help clinicians and patients when deciding a treatment plan. Patients in the best prognostic groups can be considered for more intensive or experimental therapy. Alternatively, patients in the best prognostic groups might prefer a period of observation prior to commencement of therapy. For patients with mesothelioma prognostic factors are potentially especially important because of the lack of a widely applicable anatomical staging system. Both the International Mesothelioma Interest Group (IMIG) and Brigham staging systems are of limited relevance to patients not undergoing radical debulking surgery. Radiological prediction of IMIG or Brigham stage is of little value. Review of the best-known prognostic scoring systems from the EORTC and CALGB has shown that the most important predictors of poor prognosis are: poor performance status; non-epithelioid histology; male gender; low hemoglobin; high platelet count; high white blood cell count; and high lactate dehydrogenase (LDH). The EORTC model was validated at St Bartholomew's Hospital in a group of 145 patients treated in sequential phase II chemotherapy trials. For 70 patients treated with vinorelbine, those having the best EORTC prognosis had a median survival of 19.2 months [95% C.I.=14.7-23.7] compared to 9.9 months [95% C.I.=8.5-11.3] for those in the worst group. The suggestion is that all clinical and biological factors relevant to prognosis should be recorded prospectively in mesothelioma patients selected for clinical trials.

New Agents in the Management of Advanced Mesothelioma

Malignant pleural mesothelioma (MPM) is a seemingly uncommon tumor whose incidence has in fact increased steadily and progressively over the last 30 years. Indeed, an actual "epidemic" is expected in Europe over the next 20 years. Despite unquestionable improvement in the diagnostic methods at our disposal and the availability of new treatment strategies, the prognosis of MPM patients remains dramatically poor (12 to 18 months' median survival from diagnosis), although exceptional cases of long-survivors are reported in all literature series. The current review will cover the dramatic improvements in the treatment of this rare disease that have been recently achieved, as well as the promise that new, molecular-targeted therapies, such as bortezomid, mTOR ( m ammalian t arget o f r apamycin) inhibitors, and Met inhibitors, seem to offer for the next few years. With pemetrexed we now have a drug that is able to impact patient survival. Together with the newer drugs, rapidly emerging from the laboratory to be applied in the clinic, we have the hope of making further advances in the struggle against this disease.

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.

Malignant pleural mesothelioma

Malignant pleural mesothelioma is an uncommon tumor; only about 3000 cases are diagnosed annually in the United States. Cases were described early in the 20th century, but their relationship to asbestos exposure was not documented until 1960. Since then, the incidence has appeared to increase, and numerous epidemiologic studies have confirmed that exposure to asbestos in a variety of settings and occupations is the most significant risk factor for the development of malignant pleural mesothelioma. More recently, the oncogenic virus SV40 has also been implicated as a potential etiologic agent. Surgery, radiotherapy, and chemotherapy have each been used in the treatment of mesothelioma, but generally with little impact on survival. New directions in therapy include aggressive multimodality programs for potentially resectable patients and targeted therapies, including antifolates, antiangiogenesis agents, and drugs directed at epidermal growth factor receptor for the majority of patients presenting with unresectable disease.

Phase II trial of vinorelbine and oxaliplatin as first-line therapy in malignant pleural mesothelioma

The incidence of malignant pleural mesothelioma (MPM) is increasing. Treatment options are limited, although recently published data have offered cause for optimism. We reported a response rate of 24% with low toxicity for single agent vinorelbine. Here we report a phase II trial of vinorelbine with oxaliplatin (VO) in patients with untreated MPM. Chemotherapy consisted of vinorelbine 30 mg/m(2), days 1 and 8 of a 21-day-cycle, and oxaliplatin 130 mg/m(2), day 1. Treatment continued up to six cycles. The primary endpoint was objective response. Secondary endpoints were toxicity, progression-free and overall survival. Responses were assessed by modified RECIST criteria. Twenty-six patients were enrolled. There were six partial remissions, 17 patients with stable disease, and three patients with PD. Response rate was 23% (95% confidence interval 9-44%). Median number of cycles delivered was four. Progression-free survival from first treatment was 4.7 months, and overall survival was 8.8 months. One-year-survival was 27%. Toxicity (% of patients with at least one episode of grade 3 or 4 toxicity): neutropenia 18%, phlebitis 12%, malaise 12%, anorexia 12%, nausea and vomiting 12%, constipation 6%. Quality of life assessed by Rotterdam symptom checklist was associated with stabilization or improvement of psychological well-being and lung symptoms in the majority of patients, but deterioration in physical symptoms.

CONCLUSION

VO has activity in MPM with most patients responding or having stable disease, although this doublet is associated with significant toxicity.

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.

Statistical Validation of the EORTC Prognostic Model for Malignant Pleural Mesothelioma Based on Three Consecutive Phase II Trials

Purpose

Malignant pleural mesothelioma (MPM) carries a poor prognosis due to chemoresistance. The European Organisation for Research and Treatment of Cancer (EORTC) prognostic model was reported to predict survival in MPM. Our retrospective analysis set out to test the validity of the model as a prognostic tool in patients treated in three phase II trials at St Bartholomew’s Hospital (London, United Kingdom) between 1999 and 2003.

Patients and Methods

A total of 145 patients were treated in three phase II trials; vinorelbine (VIN; 70 patients), vinorelbine/oxaliplatin (VO; 26 patients), and irinotecan/cisplatin/mitomycin C (IPM; 49 patients). Two subgroups, high-risk and low-risk, were defined by EORTC prognostic score (EPS). EPS was determined by a five-parameter model incorporating age, sex, histology, probability of diagnosis, and leukocyte count. An EPS cutoff of less than 1.27 (low risk) or more than 1.27 (high risk) was used to stratify Kaplan-Meier survival curves. Each of the EPS variables exhibited either trends or significant stratification of overall survival (OS).

Results

Multivariate analysis confirmed leukocyte count, Eastern Cooperative Oncology Group performance status, and sarcomatous histology as independent prognostic variables. EPS stratified OS in both individual and pooled trial datasets. No association between objective tumor response and EPS classification was identified by multinomial logistic regression. EPS stratified progression-free survival for the VO and IPM cohorts, but not for VIN.

Conclusion

This study validates the EPS system as a robust tool for stratifying small trials into low- and high-risk subgroups. EPS should facilitate patient selection and analysis in randomized clinical trials.

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.

Neoadjuvant Chemotherapy Followed by Extrapleural Pneumonectomy in Malignant Pleural Mesothelioma

Purpose

To investigate neoadjuvant chemotherapy with cisplatin and gemcitabine followed by extrapleural pneumonectomy with or without radiation therapy in patients with potentially resectable malignant pleural mesothelioma (MPM).

Patients and Methods

Eligible patients had MPM with clinical stage T1-3, N0-2, M0 disease considered to be completely resectable and a WHO performance status of 0 to 2. Neoadjuvant chemotherapy consisted of three cycles of cisplatin 80 mg/m2on day 1 and gemcitabine 1,000 mg/m2on days 1, 8, and 15, given every 28 days. Surgery had to consist of a complete extrapleural pneumonectomy, including resection of pericardium and diaphragm. Postoperative radiotherapy was to be considered for all patients.

Results

Nineteen patients with MPM were included in this pilot study. According to the European Organization for Research and Treatment of Cancer prognostic score, two patients were in the good prognosis group, and 17 patients were in the poor prognosis group. The response rate to neoadjuvant chemotherapy was 32%. The major toxicity was thrombocytopenia. Extrapleural pneumonectomy was performed in 16 patients with no perioperative mortality. Major surgical complications occurred in six patients, and all were treated successfully. Thirteen patients received postoperative radiotherapy. The median survival time was 23 months. Two patients remain alive and free of disease 41 and 38 months after initiation of therapy.

Conclusion

For patients with potentially operable MPM, the availability of active and well-tolerated chemotherapy regimens, the fact that extrapleural pneumonectomy can be safely performed after neoadjuvant chemotherapy in an experienced center, and the promising results regarding survival in our pilot study warrant further investigation of the role of neoadjuvant chemotherapy in a multimodality strategy.

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.

Capecitabine in malignant mesothelioma: a phase II trial by the Cancer and Leukemia Group B (39807)

PURPOSE

The CALGB performed a phase II multicenter study to evaluate the activity of oral capecitabine in patients with malignant mesothelioma (CALGB 39807).

PATIENTS AND METHODS

Between November 15, 2000 and August 31, 2001, 27 patients with mesothelioma were enrolled in this study. Capecitabine was administered at 2500 mg/m(2) per day divided in two doses for 14 days followed by a seven-day break. Cycles were repeated every 21 days with restaging performed every two cycles and therapy continuing for up to six cycles. One patient withdrew from the study prior to receiving therapy and is removed from further analysis. Eligibility criteria included no prior treatment, PS 0-1 by CALGB criteria and histologically documented mesothelioma.

PATIENT CHARACTERISTICS

gender; male 19 (73%), female seven; median age 70 (range 40-81); histology: epithelial 15 (58%), mixed eight (31%), unclassified three; site of origin pleura, 25 (96%); weight loss in previous six months of more than 10% in seven (27%), symptoms longer than six months in five (19%).

RESULTS

One patient (4%) had a confirmed PR while 10 (38%) achieved SD for 2-6 cycles. Ten patients (38%) had PD as their best response. There were three patients unevaluable for response and two early deaths. Median survival and failure free survival were 4.9 (95% CI 4-10.8) and 2.4 (95% CI 1.5-4.2) months respectively with a one-year survival of 23% (95% CI 11-49%). Grade three or greater toxicities encountered by at least 10% of patients included lymphopenia (12%), fatigue (12%), dehydration (12%) and diarrhea (15%). Three patients (12%) had grade three skin toxicity or hand-foot syndrome. One patient died of treatment related toxicity during cycle one.

CONCLUSION

The antitumor activity of capecitabine is insufficient to warrant further exploration in patients with malignant mesothelioma.

Malignant mesothelioma—the UK experience

In Britain it is estimated that the annual number of mesothelioma deaths will rise from approximately 1500 in the year 2000 to a peak of approximately 3000 in 2020. A database on the natural history of mesothelioma has provided a baseline for a new trial at The Royal Marsden looking at early versus delayed chemotherapy in mesothelioma as a new approach to treatment. In the UK chemotherapy is usually in the form of MVP (mitomycin, vinblastine and cisplatin) or vinorelbine, and data have been collected from trials covering both regimens. There is now a national working group for mesothelioma (BMIG) and a proposal for a national trial is being taken forward, comparing chemotherapy with MVP or single agent vinorelbine in addition to active symptom control (ASC) with ASC alone. Novel agents are also being investigated and SRL172 has shown some benefits in combination with chemotherapy in the treatment of malignant mesothelioma.

Do patients with weight loss have a worse outcome when undergoing chemotherapy for lung cancers?

To examine whether weight loss at presentation influences outcome in patients who received chemotherapy for lung cancer or mesothelioma. Multivariate analysis of prospectively collected data 1994–2001. Data were available for age, gender, performance status, histology, stage, response, toxicity, progression-free and overall survival. The outcomes of patients with or without weight loss treated with chemotherapy for small cell lung cancer (SCLC; n=290), stages III and IV non-small-cell lung cancer (NSCLC; n=418), or mesothelioma (n=72) were compared. Weight loss was reported by 59, 58 and 76% of patients with SCLC, NSCLC and mesothelioma, respectively. Patients with weight loss and NSCLC (P=0.003) or mesothelioma (P=0.05) more frequently failed to complete at least three cycles of chemotherapy. Anaemia as a toxicity occurred significantly more frequently in NSCLC patients with weight loss (P=0.0003). The incidence of other toxicities was not significantly affected by weight loss. NSCLC patients with weight loss had fewer symptomatic responses (P=0.001). Mesothelioma patients with weight loss had fewer symptomatic (P=0.03) and objective responses (P=0.05). Weight loss was an independent predictor of shorter overall survival for patients with SCLC (P=0.003, relative risk (RR)=1.5), NSCLC (P=0.009, RR=1.33) and mesothelioma (P=0.03, RR=1.92) and an independent predictor of progression-free survival in patients with SCLC (P=0.01, RR=1.43). In conclusion, weight loss as a symptom of lung cancer predicts for toxicity from treatment and shorter survival.

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.

BTS randomised feasibility study of active symptom control with or without chemotherapy in malignant pleural mesothelioma: ISRCTN 54469112

BACKGROUND

The incidence of mesothelioma is rising rapidly in the UK. There is no generally accepted standard treatment. The BTS recommends active symptom control (ASC). It is not known whether chemotherapy in addition prolongs survival or provides worthwhile palliation with acceptable toxicity. Palliation as recorded by patients has been fully reported for only two regimens: mitomycin, vinblastine, and cisplatin (MVP), and vinorelbine (N). The BTS and collaborators planned to conduct a phase III randomised trial comparing ASC only, ASC+MVP, and ASC+N in 840 patients with survival as the primary outcome measure. The aim of the present study was to assess the acceptability of the trial design to patients and the suitability of two standard quality of life (QL) questionnaires for mesothelioma.

METHODS

Collaborating centres registered all new patients with mesothelioma. Those eligible and giving informed consent completed EORTC QLQ-C30+LC13 and FACT-L QL questionnaires and were randomised between all three or any two of (1) ASC only, (2) ASC+4 cycles of MVP, and (3) ASC+12 weekly doses of N.

RESULTS

During 1 year, 242 patients were registered of whom 109 (45%) were randomised (55% of the 197 eligible patients). Fifty two patients from 20 centres were randomised to an option including ASC only. This translates into a rate of 312 per year from 60 centres interested in collaborating in the phase III trial. The EORTC QL questionnaire was superior to FACT-L in terms of completeness of data and patient preference. Clinically relevant palliation was achieved with ASC.

CONCLUSION

The planned phase III trial is feasible.

Factors influencing long-term survival in mesothelioma patients--results of the German mesothelioma register

Between 1987 and 2000, the German mesothelioma register recorded a total of 4,455 patients with malignant mesotheliomas. Survival times for 498 (11.2%) patients were available; 155 patients (study group, 3.5% of the total group) survived for more than 2 years and 343 patients (control group, 7.7% of the total group) survived for fewer than 24 months. Male patients were over-represented in both groups, with 13% of women in the study and 4.4% in the control group. The proportion of pleural mesotheliomas was more than 90% in both groups, with peritoneal cases comprising 6.5% in the study group and 3.2% in the control group. Histologically, the epithelioid subtype was represented in 58% of the study group, whereas the biphasic subtype predominated (67.6%) in the control group. Only 7% of tumours were of the sarcomatoid subtype. The average age of patients in the study group was 57.4 years, thus lower than in the control group (62.8 years). Lung dust analysis showed an increased pulmonary asbestos burden in 94% of all patients; significant differences between the study and control group were not observed. In the majority of the total group pleural effusions were the first symptoms. Therapeutic data were available in fewer than 40% of all cases. Surgical interventions were performed, partly in combination with radiation and chemotherapy and as alternative treatments. Significant deviations in survival time dependent on therapy applied could not be proved. By multivariate analysis (Cox proportional hazards regression model) favourable prognostic factors for long-term survival were epithelioid tumour subtype, comparatively young age (<60 years), and female gender ( P<0.05).

Malignant pleural mesothelioma: surgical roles and novel therapies

Malignant pleural mesothelioma (MPM) is a uniformly fatal disease that has been recalcitrant to curative therapies. Median survivals of 8-18 months have, for the most part, led to a sense of frustration and nihilism in the medical and surgical community with regard to management of the disease, and the relatively small numbers of patients with mesothelioma have made it an orphan among other cancers with regard to research efforts and funding. This review will comment on the clinical presentation of the disease and therapeutic options that are available at this time. The role, timing, degree, and availability of cytoreductive surgery in the context of a multimodality approach for MPM will be highlighted, and various strategies that incorporate adjunctive therapies before, during, or after the operation will be discussed. Newer cytotoxic chemotherapies, either alone or in combination, are reviewed, with an emphasis on the increasing number of options with increased response rates that are becoming available for MPM patients. The results of protocols at selected centers that offer gene therapy, photodynamic therapy, hyperthermic chemotherapeutic perfusion, and intrapleural chemokines will be discussed, as well as newer preclinical approaches that base targeted therapies on novel molecular findings. In considering the newest approaches to the disease, one is encouraged to seek specialty consultation at centers that concentrate programmatic efforts on mesothelioma in order to design translational-based approaches on preclinical findings. By using such an approach, the patient and physician will find that there are considerably more options in the new century for mesothelioma.

Symptom control

Symptom control has become increasingly recognized as an important goal in patient care. In this article, advances in symptom assessment, and various definitions of symptom improvement are reviewed. Theoretical concepts underlying symptom control and clinically significant change are presented, as well as the role of symptom control as an endpoint in clinical trials. Symptom control is then surveyed in two broad categories for selected symptoms. The first area is therapy related symptoms, secondary to chemotherapy, radiation, hormonal therapy, and surgery. Symptoms reviewed include chemotherapy related mucositis, emesis, fatigue; hot flashes; and radiation related dermatitis, xerostomia, and mucositis. The second area is palliative oncologic approaches to disease-related symptoms. Results in palliative chemotherapy, palliative radiation therapy, cancer pain, and lack of appetite are summarized. Areas requiring further research are noted. Findings are presented in both a clinical and research context to help guide the reader with interpreting symptom control studies.

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.

High-dose ifosfamide with mesna and granulocyte-colony-stimulating factor (recombinant human G-CSF) in patients with unresectable malignant mesothelioma

BACKGROUND

The current study was conducted to assess the activity and toxicity of high-dose ifosfamide and mesna with recombinant human granulocyte-colony-stimulating factor (rhG-CSF), given in an outpatient setting, in the treatment of patients with unresectable malignant mesothelioma.

METHODS

Between September 1994 and September 1996, 41 patients with histologically verified, unresectable malignant mesothelioma were registered, 38 of whom were analyzable (2 were ineligible and 1 was nonanalyzable). Patients received intravenous ifosfamide at a dose of 2.8 g/m2 over 3 hours (total dose of 14 g/m2), plus mesna at a dose of 0.56 g/m2 prior to and at 4 hours and 8 hours after ifosfamide infusion daily for 5 days every 21 days. rhG-CSF at a dose of 5 microg/kg/day was administered subcutaneously on days 6-15.

RESULTS

Response assessment could be determined adequately in 21 patients. Two patients obtained responses; 1 was a confirmed partial response (3%; 95% confidence interval [95% CI], 0-14%) and 1 was an unconfirmed response (3%; 95% CI, 5-14%). Eleven patients had stable disease (29%), 7 patients developed disease progression (18%), 1 patient had an early death (3%), and 17 patients had inadequate assessment (45%). At the time of last follow-up, 36 of the 38 eligible patients had developed disease progression, with a median progression-free survival of 5 months (95% CI, 3-7 months) and 34 patients had died with a median survival of 7 months (95% CI, 6-9 months). Twenty-four patients (63%) and 7 patients (18%), respectively, had Grade (according to Southwestern Oncology Group Toxicity Criteria) 4 hematologic toxicities and Grade 4 nonhematological toxicities. There was one treatment-related death, the result of infection, pulmonary edema, and renal failure.

CONCLUSIONS

This regimen demonstrated a low overall objective response rate with substantial toxicity, and in the opinion of the authors does not warrant further investigation in the treatment of patients with unresectable malignant mesothelioma.

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.

Phase II trial of ZD0473 as second-line therapy in mesothelioma

A phase II, open-label, non-comparative, multicentre trial of the platinum analogue ZD0473 as second-line therapy for pleural mesothelioma has been completed. The objectives were to evaluate the activity and tolerability of ZD0473 in patients with relapsed or progressive disease who had received one prior chemotherapy regimen. Forty-seven patients were recruited onto the trial, all aged > 18 years with a life-expectancy > 12 weeks, and World Health Organization (WHO) performance status < or = 2. A starting dose of 120 mg/m2 was administered to 14 patients, six of whom subsequently had their dose escalated to 150 mg/m2. Thirty-three patients received a starting dose of 150 mg/m2. In total, 147 treatment cycles were administered (median number of cycles 3 [range 1-6]). The main toxicity of ZD0473 was haematological (thrombocytopenia) and the most common non-haematological adverse event was nausea. There was no clinically significant nephro-, neuro-, or oto-toxicity. Of the 43 patients evaluable for response, 12% had a minor response (defined by a reduction in lesion size > or = 10% but < 50%), 44% had stable disease, 40% had disease progression, and two patients died before an objective response could be assigned. Median time to progression and death in evaluable patients was 77 days (95% confidence interval [CI]: 44, 105 days) and 203 days (95% CI: 165, 277 days), respectively. In conclusion, although ZD0473 demonstrated a manageable tolerability profile, no complete or partial responses were seen in second-line treatment of mesothelioma. This trial also demonstrates that clinical trials in second-line mesothelioma patients are feasible.

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.

A phase II EORTC study of temozolomide in patients with malignant pleural mesothelioma

The aim of this study was to investigate the anti-tumour activity of temozolomide in patients with malignant pleural mesothelioma. 27 chemotherapy-naïve patients with histologically-proven malignant mesothelioma were treated with temozolomide 200 mg/m2/day, given orally on days 1-5 of each 28-day cycle. Therapy continued up to 10 cycles unless disease progression or excessive toxicity mandated discontinuation. Toxicity, symptom improvement and pain intensity were regularly assessed. With a median relative dose intensity of 97%, toxicity was moderate with grade 3 or more nausea, vomiting, thrombocytopenia, leucocytopenia, neutropenia, febrile leucocytopenia, arthralgia, infection and fever with infection occurring in 13, 13, 10, 3, 7 and 3% of patients for the remaining events, respectively. Overall, 1 objective response was observed (response rate 4%, 95% Confidence Interval (CI): 0.1-19). Median survival was 8.2 months. Symptom assessment showed no improvement and an increase of pain was observed during the study. Thus, oral temozolomide is an inactive agent in malignant mesothelioma.

Clinical and immunological assessment of Mycobacterium vaccae (SRL172) with chemotherapy in patients with malignant mesothelioma

The objectives of this study were to determine the toxicity of intratumoural/intrapleural SRL172 in addition to intradermal SRL172 and standard chemotherapy (mitomycin-C, vinblastine and cisplatin) in patients with malignant mesothelioma. Patients received chemotherapy (mitomycin-C: 8 mg m(-2), vinblastine: 6 mg m(-2), cisplatin 50 mg m(-2)) on a 3-weekly basis for up to six courses. IP SRL172 injections were given 3-weekly prior to chemotherapy and escalated in groups of three patients from 1 microg to 1 mg bacilli in 10-fold increments. Patients were also given ID SRL172 at a dose of 1 mg bacilli 4-weekly. Patients were assessed for toxicity after each course of chemotherapy and for response by CT imaging. Immuno-haematological parameters were analyzed pre-treatment and 1 month after completion of treatment. There was no dose limiting toxicity with IP SRL172 although there was greater toxicity at the highest dose (n=13). There were six out of 16 partial responses (37.5%). Haemato-immunological parameters, measured in seven patients pre and post-therapy, revealed that response rate correlated with a decrease in platelet count and there was an increase in activation of natural killer cells and a decrease in the percentage of IL-4 producing T cells in all tested patients post-treatment. SRL172 can be given safely into tumour deposits and the pleural cavity in patients with malignant mesothelioma and we have established the dose for phase II testing.

The emerging role of antifolates in the treatment of malignant pleural mesothelioma

Clinicians have long regarded malignant pleural mesothelioma as a chemoresistant neoplasm and as a result no standard chemotherapy regimen has emerged. Antifolates such as methotrexate are among the most active compounds in mesothelioma, albeit based only on phase II data. Recently two antifolate-based combinations with apparently higher efficacy than older regimens have emerged: the pemetrexed/cisplatin regimen and the raltitrexed/oxaliplatin regimen. In two phase I trials with pemetrexed combined with either cisplatin or carboplatin responses occurred in five of 11 and nine of 29 patients, respectively. In a phase I trial of raltitrexed/oxaliplatin, six of 17 patients (35%) with mesothelioma achieved a partial response. In a phase II trial of raltitrexed/oxaliplatin, 14 objective responses were confirmed in 72 patients (25%) with malignant pleural mesothelioma. Indeed, responses were seen in cisplatin-refractory patients. Based on the promising results from these combination trials, two large phase III studies have begun. The first study was a multicenter, multinational trial sponsored by Eli Lilly and Company, which randomized more than 430 patients with malignant pleural mesothelioma to cisplatin with or without pemetrexed. That trial completed enrollment in February 2001 and is the largest trial ever conducted in mesothelioma. The second trial is being conducted by the European Organization for the Research and Treatment of Cancer (EORTC) and compares cisplatin with or without raltitrexed with planned accrual of 240 patients. In both trials, survival is the main endpoint. These trials will help to define the role of these new antifolates in 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.