In vitro sensitivity of normal human mesothelial and malignant mesothelioma cell lines to four new chemotherapeutic agents

In this study, we used four human mesothelioma cell lines (M14K, M24K, M25K and M38K), one transformed human mesothelial cell line (MeT-5A) and one primary mesothelial culture (UPL) to test for in vitro sensitivity to docetaxel, paclitaxel, SN-38 [an active metabolite of irinotecan (CPT-11)] and gemcitabine, as single agents. Subconfluent cell cultures were treated with 2x10(-9), 5x10(-9), 10(-8), 2x10(-8) and 5x10(-8) M concentrations of each drug for 48 h. The sensitivity was measured in terms of cell viability using the Trypan blue exclusion method. All four drugs were potent inhibitors of mesothelioma cell growth, but cell lines from different patients diverged in their sensitivity to the individual agents. In most cases docetaxel, paclitaxel and SN-38 were more potent killers of mesothelioma cells than gemcitabine. The induction of DNA damage was investigated using the Comet assay; cells from two cell lines (M14K and M25K) were treated with subtoxic 10(-8) M concentrations of each drug for 4, 24 and 48 h. Each of the agents caused a slight increase in DNA single-strand breaks at a concentration of 10(-8) M.

Phase III trial of gemcitabine plus cisplatin versus cisplatin alone in patients with locally advanced or metastatic non-small-cell lung cancer

PURPOSE

The Hoosier Oncology Group has previously reported the results of its phase II trial of the combination of cisplatin plus gemcitabine. In that study of 27 assessable patients with advanced or metastatic non-small-cell lung cancer (NSCLC), the response rate was 33%, with a median survival of 8.4 months. Based on such favorable results, the Hoosier Oncology Group designed this randomized phase III study of gemcitabine plus cisplatin compared with cisplatin alone in chemotherapy-naive patients with advanced NSCLC.

PATIENTS AND METHODS

Patients were randomized to receive either cisplatin (100 mg/m(2) intravenously on day 1 of a 28-day cycle) or the combination of cisplatin (100 mg/m(2) intravenously on day 1) plus gemcitabine (1,000 mg/m(2) administered intravenously on days 1, 8, and 15 of a 28-day cycle).

RESULTS

From August 1995 to February 1997, 522 assessable chemotherapy-naive patients were randomized. Toxicity was predominantly hematologic and was more pronounced in the combination arm, with grade 4 neutropenia occurring in 35.3% of patients compared with 1.2% of patients on the cisplatin monotherapy arm. The incidence of neutropenic fevers was less than 5% in both arms. Grade 4 thrombocytopenia occurred in 25. 4% of patients on the combination arm compared with 0.8% of patients on the cisplatin monotherapy arm. No serious hemorrhagic events related to thrombocytopenia were reported for either arm. The combination of gemcitabine plus cisplatin demonstrated a significant improvement over single-agent cisplatin with regard to response rate (30.4% compared with 11.1%, respectively; P <.0001), median time to progressive disease (5.6 months compared with 3.7 months, respectively; P =.0013), and overall survival (9.1 months compared with 7.6 months, respectively; P =.004).

CONCLUSIONS

For the first-line treatment of NSCLC, the regimen of gemcitabine plus cisplatin is superior to cisplatin alone in terms of response rate, time to disease progression, and overall survival.

Phase II study of docetaxel alternating with cisplatin in chemotherapy-naïve patients with advanced non-small cell lung cancer

The objective of this study was to evaluate a regimen of full doses of docetaxel and cisplatin, using an alternating schedule, as first-line therapy for patients with inoperable non-small cell lung cancer (NSCLC). The standard concomitant schedule does not allow full doses of both drugs to be administered. We wanted to see if there was an advantage to be gained by administering full doses of both docetaxel and cisplatin, using a different schedule. Docetaxel 100 mg/m2 was given once every 6 weeks from week 1 and cisplatin (120 mg/m2 for two doses and 100 mg/m2 thereafter) once every 6 weeks from week 4, for six cycles (three docetaxel and three cisplatin). Thirty-six of the 44 patients enrolled were evaluable for efficacy. Forty-eight percent of the patients had good (KPS 90-100%) performance status. A median of five cycles was administered, for which no dose reductions were necessary. There were 13 of 36 partial responses (36%; 95% CI 21-54%) and 15 of 36 patients achieved stable disease (42%). The median duration of response was 10.5 months, the median time to progression was 4.5 months and the median survival was 9 months. The 1 and 2 year survival rates were 39 and 16%, respectively. The most frequent grade 3-4 toxicities were nausea (23% of patients), vomiting (18%) and neutropenia (77%). Infections were also common, but not severe. The alternating schedule produced response, toxicity and survival figures that compared favorable with those using the concomitant schedule. This study could serve as a model for future studies of non-cisplatin-containing regimens, in which full doses of docetaxel could alternate with full doses of other new agents active against NSCLC.

Docetaxel (Taxotere) in the neo-adjuvant setting in non-small-cell lung cancer

BACKGROUND

There is a potential for neo-adjuvant chemotherapy to provide significant benefit in outcome for patients with locally advanced non-small-cell lung cancer (NSCLC). Patients with N2/T3 NSCLC have a poor prognosis when treated by surgery alone since micrometastases result in relapse in the majority of cases. The same is true of patients with N3/T4 disease treated only with radiotherapy. Systemic therapy is therefore required, and cisplatin-based induction chemotherapy prior to surgery or radiotherapy has been shown to improve survival when compared with surgery or radiotherapy alone. Docetaxel has been shown to have significant activity in stage IV NSCLC and ongoing phase III trials are comparing single agent docetaxel or doceatxel in combination with cisplatin or VP16 before local treatment to local treatment alone.

DESIGN

Patients with locally-advanced (stage IIIa or IIIb) NSCLC receive three cycles of docetaxel (100 mg/m2) followed by appropriate local therapy, or local therapy alone. Local therapy for stage IIIa patients is surgery (with or without radiotherapy depending on completeness of resection) and for stage IIIb patients curative intent radiotherapy. In another on-going study in stage IIIa NSCLC, docetaxel (75 mg/m2) is given in combination with cisplatin (40 mg/m2) followed by surgery. Patients must have histologically or cytologically confirmed NSCLC, have received no prior treatment for the disease and are suitable to undergo surgery or radical radiotherapy, as appropriate.

RESULTS

Initial results from the phase III comparative study show that single agent docetaxel in the neo-adjuvant setting is effective and associated with acceptable toxicity. Two hundred of the planned two hundred ninety-two patients have been accrued to the single-agent docetaxel neo-adjuvant study. In the first 49 evaluable patients in the docetaxel arm, 1 CR and 18 PR have been achieved (response rate 39%) and no patients receiving docetaxel neo-adjuvant therapy have progressed. All patients were able to receive the full doses of docetaxel.

CONCLUSION

The details of time-to-progression and survival in this study will eventually confirm the results from recent small trials of neo-adjuvant chemotherapy in locally-advanced NSCLC.

Deletions at 14q in malignant mesothelioma detected by microsatellite marker analysis

Previous molecular cytogenetic studies by comparative genomic hybridization (CGH) on primary tumours of human malignant mesothelioma have revealed that loss of genetic material at chromosome 14q is one of the most frequently occurring aberrations. Here we further verify the frequency and pattern of deletions at 14q in mesothelioma. A high-resolution deletion mapping analysis of 23 microsatellite markers was performed on 18 primary mesothelioma tumours. Eight of these had previously been analysed by CGH. Loss of heterozygosity or allelic imbalance with at least one marker was detected in ten of 18 tumours (56%). Partial deletions of varying lengths were more common than loss of all informative markers, which occurred in only one tumour. The highest number of tumours with deletions at a specific marker was detected at 14q11.1-q12 with markers D14S283 (five tumours), D14S972 (seven tumours) and D14S64 (five tumours) and at 14q23-q24 with markers D14S258 (five tumours), D14S77 (five tumours) and D14S284 (six tumours). We conclude from these data that genomic deletions at 14q are more common than previously reported in mesothelioma. Furthermore, confirmation of previous CGH results was obtained in all tumours but one. This tumour showed deletions by allelotyping, but did not show any DNA copy number change at 14q by CGH. Although the number of tumours allelotyped was small and the deletion pattern was complex, 14q11.1-q12 and 14q23-q24 were found to be the most involved regions in deletions. These regions provide a good basis for further molecular analyses and may highlight chromosomal locations of tumour suppressor genes that could be important in the tumorigenesis of malignant mesothelioma.

Single-agent gemcitabine: an active and better tolerated alternative to standard cisplatin-based chemotherapy in locally advanced or metastatic non-small cell lung cancer

This randomized study was designed to determine the response rates, survival and toxicities of single-agent gemcitabine (GEMZAR) and a combination of cisplatin/etoposide in chemonaive patients with non-resectable, locally advanced or metastatic non-small cell lung cancer (NSCLC). Gemcitabine 1000 mg/m2 was given as a 30-min intravenous infusion on days 1, 8, 15 of a 28-day cycle, cisplatin 100 mg/m2 on day 1, and etoposide 100 mg/m2 on days 1 (following cisplatin), 2 and 3. Major eligibility criteria included histologically confirmed non-small cell lung cancer, measurable disease, Zubrod performance status 0-2, no prior chemotherapy, no prior radiation of the measured lesion, and no CNS metastases. One hundred and forty-seven patients were enrolled, 72 in the gemcitabine and 75 in the cisplatin/etoposide arm. Patient characteristics were well-matched across both arms. Sixty-seven gemcitabine and 72 cisplatin/etoposide patients were qualified for efficacy analysis. There were no complete responses, but 12 partial responses in the gemcitabine arm and 11 in the cisplatin/etoposide arm, for protocol-qualified response but 12 partial responses in the gemcitabine arm and 11 in the cisplatin/etoposide arm, for protocol-qualified response rates of 17.9% (95%, CI: 9.6-29.2%,) and 15.3% (95% CI: 7.9-25.7%,), respectively. Median survival times were 6.6 months (95% CI: 4.9-7.3 months) for gemcitabine and 7.6 months (95% CI: 5.4-9.3 months) for cisplatin/etoposide. The 1-year survival probability estimate was 26% for gemcitabine and 24% for cisplatin/etoposide. There were no statistically significant between-group differences in time-to-event measures, but patients in the gemcitabine arm had a greater probability of achieving a tumour response after 2 months (probability estimate: 8 vs. 0%,) and of the response lasting at least 6 months (73 vs. 45%,). Clinical and haematologic toxicity was more pronounced in the cisplatin/etoposide arm. Quality-of-life measures indicated a significant worsening of symptomatology in the cisplatin/etoposide arm for hair loss, nausea and vomiting, and appetite loss. This randomized study provides further evidence that single-agent gemcitabine is an active and effective therapy for patients with non-resectable. locally advanced or metastatic NSCLC and good performance status, and that it is better tolerated than the combination cisplatin/ etoposide.

Simian virus 40 (SV40)-like DNA sequences not detectable in finnish mesothelioma patients not exposed to SV40-contaminated polio vaccines

Occupational asbestos exposure can be demonstrated in 80% of mesothelioma cases. A possible role of simian virus 40 (SV40) in the etiology of mesothelioma was raised because several studies reported the presence and expression of SV40-like DNA sequences in human mesotheliomas. It is also known that expression of SV40 large T antigen inhibits cellular Rb and p53. This suggests that SV40 might render infected cells more susceptible to asbestos carcinogenicity. The SV40-like sequences are suggested to have arisen from contaminated polio vaccines. Millions of people in the United States and most European countries were inoculated with SV40-contaminated polio vaccine in 1955-1963. However, in Finland, where polio vaccination started in 1957, no SV40-contaminated vaccine was used. We used a polymerase chain reaction-based method to test for the presence of SV40-like sequences in DNA extracted from the frozen tumor tissues of 49 Finnish mesothelioma patients, most of whom had been occupationally exposed to asbestos. All of the Finnish tumor tissues tested negative for SV40-like sequences. The results suggest that the SV40-like sequences detected in mesothelioma tissue in some previous studies may indeed originate from SV40-contaminated polio vaccines. It is a matter of speculation whether the absence of SV40 infection has contributed to the relatively low incidence of mesothelioma in Finland (1/10(5) in 1990-1995).

Phase II study of vinorelbine and gemcitabine for inoperable stage IIIB-IV non-small-cell lung cancer

PURPOSE

To evaluate the efficacy of the combination of vinorelbine and gemcitabine as a non-platinum chemotherapy regimen in patients with inoperable locally-advanced or metastatic non-small-cell lung cancer (NSCLC). Efficacy was assessed primarily in terms of response rate, and secondarily in terms of toxicity, time to progression and survival.

PATIENTS AND METHODS

Patients with cytologically- or histologically-proven stage IIIB-IV NSCLC, bi-dimensionally measurable lesions, adequate haematological, hepatic and renal function, WHO performance status < or = 2 and no previous chemotherapy or radiotherapy were eligible. The first 12 patients were entered in a pilot study and received vinorelbine (VNR) 30 mg/m2 on days 1, 8, 15 and 22, and gemcitabine (GEM) 1000 mg/m2 on days 1, 8 and 15, of a 28-day cycle. Subsequently, patients were entered in a phase II trial of VNR 35 mg/m2 and GEM 1200 mg/m2 on days 1 and 15 of each 28-day cycle. Treatment consisted of three cycles of the chemotherapy, with a further three cycles for those patients who achieved stable disease or a complete or partial response (CR/PR) to the first three cycles. Patients who had achieved CR or PR after six cycles continued with the treatment until relapse.

RESULTS

The dosage and scheduling of VNR and GEM in the pilot study resulted in neutropenia necessitating reductions or delays in treatment, and consequently low dose intensity. The schedule was thus modified to VNR 35 mg/m2 and GEM 1200 mg/m2 on days 1 and 15 of each 28-day cycle for the phase II trial. Thirty-three patients were enrolled in the phase II trial, and 28 were evaluable for response. The overall intent-to-treat response rate of all 45 patients was 40% (18 of 45), comprising 4 CR (9%) and 14 PR (31%). For the 28 evaluable patients who received the fortnightly chemotherapy the response rate was 46% (13 of 28), CR 11% (3 of 28) and PR 36% (10 of 28). Seven patients (25%) had stable disease. The one-year cumulative survival rate for the 33 patients receiving the fortnightly chemotherapy was 24% and median time-to-progression 4 months (range 1-16 months). Median survival for these patients was eight months. Nine out of twelve patients in the pilot study (75%) suffered grade 3-4 neutropenia. There was one toxic death, attributed to neutropenic fever and sepsis, and two cases of pulmonary embolism. One patient suffered Grade 4 thrombocytopenia. Only eight patients (24%) on the fortnightly schedule suffered grade 3-4 neutropenia, resulting in dose reductions or delays for three of them (9%). None of the patients on the fortnightly schedule suffered thrombocytopenia or anaemia.

CONCLUSIONS

The fortnightly schedule of gemcitabine and vinorelbine was a well-tolerated out-patient regimen, producing response and survival rates comparable to those of cisplatin combination regimens, but with a more favourable toxicity profile. Gemcitabine and vinorelbine should now be tested in a triplet combination with a taxane as the third drug, or against a platinum-containing regimen in a phase III study.

High-dose methotrexate in combination with interferons in the treatment of malignant pleural mesothelioma

Twenty six patients with pleural mesothelioma of UICC stage I-IV excluding M1 disease (46% of whom had stage I disease and 38% stage III disease) were treated intravenously with high dose MTX (3 g) and calcium folinate rescue three times at intervals of 2 weeks and three times at intervals of 3 weeks. Natural interferon (IFN)-alpha (3 MIU days 2-10) and recombinant IFN-gamma1b (50 microg m(-2) on days 2, 6 and 10) were injected subcutaneously after each MTX dose. At the end of MTX treatment the IFNs were continued as maintenance therapy until disease progression. Seven partial responses were observed among 24 patients evaluable for response (response rate 29%, 95% confidence interval 13-51%). Median duration of response was 10 months (range 3-24 months). Median survival was 17 months and 1-year and 2-year survival rates 62% and 31% respectively. The toxicity of the chemo-immunotherapy was acceptable. Treatment was stopped in one patient who developed grade IV neurological toxicity. MTX dose reductions were rare (two patients with grade 1-2 renal toxicity). The combination of high dose MTX and IFN-alpha and IFN-gamma is active against malignant pleural mesothelioma and well-tolerated. The survival rates are encouraging.

A controlled study of postoperative radiotherapy for patients with completely resected nonsmall cell lung carcinoma. Groupe d'Etude et de Traitement des Cancers Bronchiques

BACKGROUND

Postoperative radiotherapy is commonly used to treat patients with completely resected nonsmall cell lung carcinoma, but its effect on overall survival has not been established.

METHODS

After undergoing complete surgical resection, 728 patients with non-small cell lung carcinoma (221 Stage I, 180 Stage II, and 327 Stage III) were randomized to receive either postoperative radiotherapy at a total dose of 60 gray or observation only . The main end point was overall survival.

RESULTS

At the reference date, 218 of 355 patients in the control group had died and 262 of 373 in the radiotherapy group had died. Five-year overall survival was 43% for the control group and 30% for the radiotherapy group (P = 0.002, log rank test; relative risk [RR]: 1.33; 95% confidence interval [CI]: 1.11-1.59). This result was not modified by adjustment for potential prognostic factors. The excess mortality rate for the radiotherapy group was due to an excess of intercurrent deaths (P = 0.0001; RR: 3.47; the 5-year intercurrent death rate was 8% for the control group and 31% for the radiotherapy group). Radiotherapy had no significant effect on local recurrence (RR: 0.85; 95% CI: 0.64-1.14) and no effect on metastasis (RR: 1.06; 95% CI: 0.85-1.31). The rate of non-cancer-related death increased with the dose per fraction delivered.

Docetaxel (Taxotere) and neoadjuvant chemotherapy for non-small cell lung cancer

In locally advanced non-small cell lung cancer with ipsilateral (N2) or contralateral (N3) mediastinal node involvement, the presence of micrometastases results in a poor outcome when patients are treated by surgery alone. The prognosis is also bad in inoperable locally advanced disease (T4) treated solely by radiotherapy. Compared with surgery or radiotherapy alone, the additional use of cisplatin-based induction chemotherapy has been shown to significantly increase the prospects of long-term survival in these patients. Data from the first large, randomized study of docetaxel (Taxotere; Rhône-Poulenc Rorer, Antony, France) 100 mg/m2 every 3 weeks in neoadjuvant chemotherapy show good activity in stage III patients who have completed treatment. Toxicity was acceptable. Febrile neutropenia was experienced by 22% of patients, complicating only 3% of the 233 cycles administered. Several ongoing phase I/II studies are investigating neoadjuvant regimens in which docetaxel is combined with agents such as cisplatin and carboplatin. In preliminary results from a study of docetaxel plus cisplatin, an objective response was seen in 70% of 20 evaluable patients. It is hoped that the use of docetaxel in single-agent or combination induction regimens will prove to prolong patient survival.

Asbestos induction of extended lifespan in normal human mesothelial cells: interindividual susceptibility and SV40 T antigen

Normal human mesothelial cells from individual donors were studied for susceptibility to asbestos-induction of apoptosis and generation of an extended lifespan population. Such populations were generated after death of the majority of cells and arose from a subset of mesothelial cultures (4/16) whereas fibroblastic cells (5/5) did not develop extended lifespan populations after asbestos exposure. All mesothelial cultures were examined for the presence of SV40 T antigen to obtain information on (i) the presence of SV40 T antigen expression in normal human mesothelial cells and (ii) the relationship between generation of an extended lifespan population and expression of SV40 T antigen. Immunostaining for SV40 T antigen was positive in 2/38 normal human mesothelial cultures. These cultures also had elevated p53 expression. However, the two isolates expressing SV40 T antigen did not exhibit enhanced proliferative potential or develop an extended lifespan population. Asbestos-generated extended lifespan populations were specifically resistant to asbestos-mediated but not to alpha-Fas-induced apoptosis. Deletion of p16Ink4a was shown in 70% of tumor samples. All mesothelioma cell lines examined showed homozygous deletion of this locus which extended to exon 1beta. Extended lifespan cultures were examined for expression of p16Ink4a to establish whether deletion was an early response to asbestos exposure. During their rapid growth phase, extended lifespan cultures showed decreased expression of p16Ink4a relative to untreated cultures, but methylation was not observed, and p16Ink4a expression became elevated when cells entered culture crisis. These data extend the earlier observation that asbestos can generate extended lifespan populations, providing data on frequency and cell type specificity. In addition, this report shows that generation of such populations does not require expression of SV40 T antigen. Extended lifespan cells could represent a population expressing early changes critical for mesothelioma development. Further study of these populations could identify such changes.

Concomitant chemotherapy and IFN-alpha for small cell lung cancer: a randomized multicenter phase III study

Patients with any stage of small cell lung cancer were given low-dose interferon-alpha (IFN-alpha) from the first day of treatment as long as possible irrespective of changes in treatment dictated by disease progression. All patients received 6 cycles of the chemotherapy (CT): cisplatin 70 mg/m2 i.v. day 1 and etoposide 100 mg/m2 i.v. days 1, 2, 3 every 28 days. Seventy-eight patients were assigned to arm 1: CT alone, 75 patients to arm 2: CT + natural IFN-alpha (3 MU three times a week i.m.), and 66 patients to arm 3: CT + recombinant IFN alpha-2a (3 MU three times a week i.m.). There was no difference in median survival between the arms (10.2 months, 10.0 months, 10.1 months, respectively), p = 0.32. The 2-year survival rates were 15%, 3%, and 11%, respectively. Grade 3 and 4 leukopenia occurred more frequently in the IFN arms than in the CT alone arm and resulted in dose reductions. Antibodies occasionally developed to recombinant IFN. We conclude that IFN-alpha can be administered concomitantly with chemotherapy but is probably better kept for maintenance therapy so that optimal full doses of induction CT can be given.

Tumour response and radiation-induced lung injury in patients with recurrent small cell lung cancer treated with radiotherapy and concomitant interferon-alpha

The aim of this study was to determine whether either natural or recombinant interferon (IFN)-alpha can improve the response to radiotherapy (RT) in patients with small cell lung cancer (SCLC), and to assess the role of IFN in radiation-induced lung injury. All patients had previously participated in a randomised trial of chemotherapy alone or in combination with IFN-alpha in three arms (arm O: no IFN, arm I: natural IFN-alpha, arm II: recombinant IFN-alpha). Patients with locally progressive disease in the lungs following chemotherapy were treated with RT and they continued with their concomitant IFN-alpha. The RT dose was 50 Gy. Radiation-induced lung injury was assessed by lung function tests, computed tomography and bronchoalveolar lavage fluid (BALF) analysis which included cell findings, Interleukin (IL)-1 alpha/-1 beta expression by alveolar macrophages and surfactant components. Seventeen patients were entered in the study, 16 of whom were evaluable. Response rates in Arms O, I and II were 50, 67 and 50%, respectively. Median survival was 18.5, 7 and 23 months respectively, and 1-year survival was 67, 29 and 75% respectively. Long-term survival as assessed by 2- and 3-year survival rates was 29% in patients receiving natural IFN-alpha as compared to 17% in patients not receiving IFN (not statistically significant findings). Every patient had abnormal results when assessed for radiation-induced lung injury. No statistically significant difference was found in toxicity between the treatment arms. A high surfactant protein (SP)-A/phospholipid ratio and a high level of SP-A in BALF before RT was associated with a high degree of radiation-induced lung injury measured by lung function tests and computed tomography in all arms of the study. Thus, we could not show that the combination of IFN-alpha and RT induced more lung toxicity than RT alone as we did in our previous study. The role of high SP-A/phospholipid ratios and high SP-A levels in BALF before RT as predictors of the development of lung injury after RT needs to be determined in the future.

The clinical importance of magnetic resonance imaging versus computed tomography in malignant pleural mesothelioma

There is no standard therapy for malignant pleural mesothelioma (MPM), but recent reports have shown that extensive surgery combined with chemo- and radiotherapy prolongs the survival of selected patients with early stage disease. This emphasises the need for accurate staging procedures at diagnosis and reliable imaging methods to assess response to treatment. Computed tomography (CT) of the chest has been the standard imaging method for these purposes for the last decade, but it is limited in its ability to demonstrate accurately the platelike growth pattern of MPM within the thorax due to the partial volume effect on curved surfaces. In order to define the value of magnetic resonance imaging (MRI) in the imaging of MPM, we have compared the findings from 26 parallel paired CT and MRI scans of mesothelioma patients at various stages of the disease. MRI showed tumour spread into the interlobar fissures, tumour invasion of the diaphragm and through the diaphragm, and invasion of bony structures better than CT. Invasion of the chest wall and mediastinal soft tissue and tumour growth into the lung parenchyma were equally well seen on both imaging methods. CT was better for detecting the inactive pleural calcifications. MRI is a sensitive detector of the characteristic growth pattern and extension of MPM and we recommend its use more widely for the clinical management of MPM especially when evaluating tumour resectability and in research protocols when an accurate evaluation of disease extent is essential.

High pre-treatment serum level of vascular endothelial growth factor (VEGF) is associated with poor outcome in small-cell lung cancer

Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis and vascular permeability. Increased serum VEGF concentrations (S-VEGF) have been found in patients with various types of human cancer, including cancer of the lung. However, the clinical and prognostic significance of S-VEGF in cancer is unknown. We measured S-VEGF, using enzyme-linked immunosorbent assay, in sera taken from 68 untreated patients with small-cell lung cancer (SCLC) at the time of diagnosis. The patients were treated with 6 cycles of cisplatin and etoposide, and were randomly assigned to receive recombinant interferon, leukocyte interferon or neither. S-VEGF ranged from 70 to 1738 pg/ml (mean, 527 pg/ml). The patients who achieved partial or complete response to treatment had lower pre-treatment S-VEGF than the non-responding patients (p = 0.0083, Mann-Whitney test). High (>527 pg/ml) S-VEGF was associated with poor survival (p = 0.012, Log Rank Test), and all 3-year survivors had lower than mean pre-treatment S-VEGF. In a multivariate analysis, S-VEGF and stage were the only independent prognostic factors, and the estimated 3-year survival of the patients with limited stage disease and low pretreatment S-VEGF (n = 17, 25% of all patients) was 41% (p = 0.0055, log rank test). These data show that high pretreatment S-VEGF is associated with poor response to treatment and unfavourable survival in patients with SCLC treated with combination chemotherapy with or without interferon.

Paclitaxel (Taxol) and carboplatin followed by concomitant paclitaxel, cisplatin and radiotherapy for inoperable stage III NSCLC

We assessed the efficacy and toxicity of low-dose paclitaxel (Taxol) given combined with carboplatin before radiotherapy, and with cisplatin concomitantly with radiotherapy, in 27 patients with previously untreated inoperable stage IIA/IIIB non-small cell lung cancer. The induction chemotherapy consisted of paclitaxel 135 mg/m2 given over 1 h on day 1 and carboplatin 200 mg/m2 on day 2 repeated every 3 weeks for three cycles. Patients free of progression after induction chemotherapy received megavoltage radiation (56 Gy, 2 Gy/fraction) along with paclitaxel (30 mg/m2/1 h) and cisplatin (30 mg/m2/1 h) given 2-4 h before irradiation on days, 1, 2, 3, 22, 23 and 24. A combination of antero-posterior and oblique treatment fields was used to limit the dose to the spinal cord and to the left side of the heart to 36 Gy. The overall response rate was 78% (complete response, 19%). With a median follow-up of 19 months the median survival is 12 months, the estimated 2-year survival rate is 36%, and all patients with a complete response survived for at least 12 months after starting treatment. A total of 17 deaths occurred with metastases predominantly in the brain. Major acute toxicities (> grade 3) during induction chemotherapy included leuko-/neutropenia (n = 5/27, 19%), and during chemoradiotherapy leuko-/neutropenia (n = 10/23, 43%), thrombocytopenia (n = 1, 4%), oesophagitis (n = 3, 13%) and pneumonitis (n = 7, 30%). No toxic deaths occurred. Marked renal toxicity was not observed. We conclude that this chemoradiotherapy regimen is effective and well-tolerated, and should be further evaluated in a randomised phase III trial.

DNA gains in 3q occur frequently in squamous cell carcinoma of the lung, but not in adenocarcinoma

We performed a comparative genomic hybridization study on 25 samples of adenocarcinoma and 19 samples of squamous cell carcinoma of the lung to detect recurrent changes in the genetic material. DNA copy number changes were found in 16 squamous cell carcinoma samples and 17 adenocarcinoma samples. The most common changes were gains of DNA sequences in 3q (43%), 1q (34%), 8q (32%), 5p, (30%), 7p (25%), and 12p (25%). Of the squamous cell carcinoma samples with DNA copy number changes, 94% (15/16) had a gain in 3q (minimal common region of overlap q24-qter), whereas only 24% (4/17) of the adenocarcinoma samples with DNA copy number changes showed a gain in 3q (q22-qter) (P < 0.001). Six high-level amplifications in 3q (q26.2-q26.3) were detected in the squamous cell carcinoma samples but none were observed in the adenocarcinoma samples. Our results suggest that amplification of genes in 3q may be important in the tumorigenesis of squamous cell carcinoma but not necessarily of adenocarcinoma.

High pre-treatment serum level of vascular endothelial growth factor (VEGF) is associated with poor outcome in small-cell lung cancer

Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis and vascular permeability. Increased serum VEGF concentrations (S-VEGF) have been found in patients with various types of human cancer, including cancer of the lung. However, the clinical and prognostic significance of S-VEGF in cancer is unknown. We measured S-VEGF, using enzyme-linked immunosorbent assay, in sera taken from 68 untreated patients with small-cell lung cancer (SCLC) at the time of diagnosis. The patients were treated with 6 cycles of cisplatin and etoposide, and were randomly assigned to receive recombinant interferon, leukocyte interferon or neither. S-VEGF ranged from 70 to 1738 pg/ml (mean, 527 pg/ml). The patients who achieved partial or complete response to treatment had lower pre-treatment S-VEGF than the non-responding patients (p = 0.0083, Mann-Whitney test). High (>527 pg/ml) S-VEGF was associated with poor survival (p = 0.012, Log Rank Test), and all 3-year survivors had lower than mean pre-treatment S-VEGF. In a multivariate analysis, S-VEGF and stage were the only independent prognostic factors, and the estimated 3-year survival of the patients with limited stage disease and low pretreatment S-VEGF (n = 17, 25% of all patients) was 41% (p = 0.0055, log rank test). These data show that high pretreatment S-VEGF is associated with poor response to treatment and unfavourable survival in patients with SCLC treated with combination chemotherapy with or without interferon.

Manganese superoxide dismutase in healthy human pleural mesothelium and in malignant pleural mesothelioma

We hypothesized that manganese superoxide dismutase (MnSOD), known to be induced in rat mesothelial cells by asbestos fibers, cytokines, and hyperoxia, may also be induced in asbestos-related pleural diseases such as mesothelioma. MnSOD was assessed in healthy human pleural mesothelium (n = 6), in biopsy samples of human pleural mesothelioma (n = 7), in transformed nonmalignant human mesothelial cells (Met5A), and in two human mesothelioma cell lines (M14K and M38K) established from the tumor tissue of mesothelioma patients. There was no MnSOD immunoreactivity in five of the six samples of healthy pleural mesothelium, whereas MnSOD immunoreactivity was high in the tumor cells in all the mesothelioma samples. Northern blotting, immunohistochemistry, Western blotting, and specific activity measurements showed lower MnSOD in the nonmalignant Met5A mesothelial cells than in the M14K and M38K mesothelioma cells. In additional experiments the mesothelial and mesothelioma cells were exposed to menadione, which generates superoxide intracellularly, and to epirubicin, a cytotoxic drug commonly used to treat mesothelioma. The M38K mesothelioma cells were most resistant to menadione and epirubicin when assessed by LDH release or by adenine nucleotide (ATP, ADP, and AMP) depletion. These same cells showed not only the highest MnSOD levels, but also the highest mRNA levels and activities of catalase, whereas glutathione peroxidase and glutathione reductase levels did not differ significantly. We conclude that MnSOD expression is low in healthy human pleural mesothelium and high in human malignant mesothelioma. The most resistant mesothelioma cells contained coordinated induction of MnSOD and catalase.

Comparison of DNA copy number changes in malignant mesothelioma, adenocarcinoma and large-cell anaplastic carcinoma of the lung

The differential diagnosis of mesothelioma, primary adenocarcinomas and pleural metastases frequently causes problems. We have used the comparative genomic hybridization (CGH) technique on 34 malignant mesotheliomas and 30 primary lung carcinomas (adenocarcinoma, including bronchoalveolar carcinoma and large-cell anaplastic carcinoma) to compare their copy number changes and to evaluate the use of CGH to distinguish between these two types of tumour. In mesothelioma, gains of genetic material occurred as frequently as losses, whereas gains predominated over losses in carcinoma. In mesothelioma, the most frequent changes were losses in 4q, 6q and 14q and gains in 15q and 7p, whereas gains in 8q, 1q, 7p, 5p and 6p were the most common changes in carcinoma. Amplification of KRAS2 was detected in two adenocarcinomas by Southern blot analysis. CGH showed gains in 12p in the same tumours. Statistically significant differences between the two types of tumour were detected in chromosomes X, 1, 2p, 4, 8q, 10q, 12p, 14q, 15q and 18q. When comparing the frequency of gains and losses between mesothelioma and lung carcinoma using discriminant analysis, the sensitivity of CGH to differentiate mesotheliomas from lung carcinomas was 81% and the specificity 77%. The differences in DNA copy number changes between the two types of tumour suggest that they are genetically different tumour entities. Although CGH cannot be used as a definitive discriminatory method, we were able to distinguish between mesothelioma and lung carcinoma in a large proportion of the abnormal cases.