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New test better than immunohistochemistry?
Newsdesk
New test better than immunohistochemistry? not convinced by the new technique: “the findings are interesting but remain to be independently validated. With immunohistochemistry techniques, most experts agree that the distinction between the two entities is rather straightforward; the only exception is desmoplastic mesothelioma. In summary, I am not sure whether the genetic profiling assay offers any additional information to that which can be accomplished by immunophenotyping”. However, Holloway believes the test is an improvement on immunohistochemistry: “[it uses] a panel of antibody markers on cells collected from malignant pleural effusion. This can be a difficult assessment, particularly when there is some doubt as to the origin of the effusion. Unfortunately, it seems that no one marker is able to provide an unequivocal diagnosis, although a panel of markers can sometimes
come close. What often happens is that a definitive diagnosis can not be made, and a biopsy is then required. Our test avoids the subjective nature of immunohistochemistry scoring—and potentially the need for a biopsy”.
Cathel Kerr
Pasieka/Science Photo Library
A newly devised genetic test could differentiate between lung adenocarcinoma and mesothelioma (Clin Cancer Res 2006; 12: 5129–35). Lead author Andrew Holloway (Peter MacCallum Cancer Centre, Melbourne, VIC, Australia) explains that the test “relies on expression of a set of 17 genes differentially expressed between lung adenocarcinoma and malignant mesothelioma, but not expressed in normal mesothelial cells. We identified the genes in a large, publicly available microarray dataset and then translated it to a reverse transcriptase [RT]-PCR-based test which can be used on fresh or fixed samples of cells from malignant pleural effusions”. When the assay was used on 13 independent samples from biopsyproven malignant mesothelioma and lung adenocarcinoma, all samples were identified correctly. Views differ on the new test. Hadi Yaziji (Ancillary Pathways, Miami, FL, USA) is
New genetic test for lung cancer
Topotecan adds no benefit in advanced ovarian cancer Sequential addition of topotecan to carboplatin and paclitaxel does not improve overall response or progression-free or overall survival in patients with ovarian cancer, according to results of a randomised phase III trial, (J Natl Clin Inst 2006; 98: 1036–45). Thus, the regimen cannot be recommended as a new standard of care. High recurrence and mortality in ovarian cancer have prompted a search for better first-line chemotherapy. One option is to introduce a third, non-cross-resistant drug to the nowfavoured treatment with carboplatin and paclitaxel. Topotecan has been deemed a possible candidate, owing to its efficacy in recurrent ovarian cancer. Patients with previously untreated stage IIB–IV ovarian cancer were randomly assigned to six 21-day cycles of carboplatin and paclitaxel followed by either four 21-day cycles of topohttp://oncology.thelancet.com Vol 7 October 2006
tecan (n=658) or surveillance (n=650). If needed, patients could receive up to four extra cycles of carboplatin and paclitaxel, but these cycles had to be completed before topotecan began. Median progression-free survival was 18·2 months for those who received topotecan compared with 18·5 months in those who did not (hazard ratio 0·97; 95% CI 0·85–1·10) and median overall survival was 43·1 months for patients receiving the triplet treatment, compared with 44·5 months for those who did not receive topotecan (1·01; 0·86–1·18). Likewise, estimated 3-year survival did not differ between the groups (55·7% [95% CI 51·6–59·5] with topotecan, and 58·5% [54·4–62·3] without topotecan). Sequential addition of topotecan to carboplatin and paclitaxel resulted in increased haematological toxic effects and infections, with a significantly increased need in supportive care. How-
ever, no notable difference was seen in febrile neutropenia (3% vs 3%). Lead author Jacobus Pfisterer (University Hospital Mannheim, Mannheim, Germany) says that their negative results were not surprising and that no follow-up studies were being planned: “We tested a hypothesis”, he comments, “Clinical science is about waiting for results and weighing results”. “Topotecan is a good agent for recurrent ovarian cancer, but it is not going to help us effect a ‘cure’ for women with advanced stage disease”, says Beth Kaplan (CedarsSinai Medical Centre, Los Angeles, CA, USA). She thinks that researchers should instead consider studying new targeted treatments (eg, angiogenesis inhibitors, tyrosine-kinase inhibitors) as adjuncts to cytotoxic regimens.
Paula Gould 799
New test better than immunohistochemistry? not convinced by the new technique: “the findings are interesting but remain to be independently validated. With immunohistochemistry techniques, most experts agree that the distinction between the two entities is rather straightforward; the only exception is desmoplastic mesothelioma. In summary, I am not sure whether the genetic profiling assay offers any additional information to that which can be accomplished by immunophenotyping”. However, Holloway believes the test is an improvement on immunohistochemistry: “[it uses] a panel of antibody markers on cells collected from malignant pleural effusion. This can be a difficult assessment, particularly when there is some doubt as to the origin of the effusion. Unfortunately, it seems that no one marker is able to provide an unequivocal diagnosis, although a panel of markers can sometimes
come close. What often happens is that a definitive diagnosis can not be made, and a biopsy is then required. Our test avoids the subjective nature of immunohistochemistry scoring—and potentially the need for a biopsy”.
Cathel Kerr
Pasieka/Science Photo Library
A newly devised genetic test could differentiate between lung adenocarcinoma and mesothelioma (Clin Cancer Res 2006; 12: 5129–35). Lead author Andrew Holloway (Peter MacCallum Cancer Centre, Melbourne, VIC, Australia) explains that the test “relies on expression of a set of 17 genes differentially expressed between lung adenocarcinoma and malignant mesothelioma, but not expressed in normal mesothelial cells. We identified the genes in a large, publicly available microarray dataset and then translated it to a reverse transcriptase [RT]-PCR-based test which can be used on fresh or fixed samples of cells from malignant pleural effusions”. When the assay was used on 13 independent samples from biopsyproven malignant mesothelioma and lung adenocarcinoma, all samples were identified correctly. Views differ on the new test. Hadi Yaziji (Ancillary Pathways, Miami, FL, USA) is
New genetic test for lung cancer
Topotecan adds no benefit in advanced ovarian cancer Sequential addition of topotecan to carboplatin and paclitaxel does not improve overall response or progression-free or overall survival in patients with ovarian cancer, according to results of a randomised phase III trial, (J Natl Clin Inst 2006; 98: 1036–45). Thus, the regimen cannot be recommended as a new standard of care. High recurrence and mortality in ovarian cancer have prompted a search for better first-line chemotherapy. One option is to introduce a third, non-cross-resistant drug to the nowfavoured treatment with carboplatin and paclitaxel. Topotecan has been deemed a possible candidate, owing to its efficacy in recurrent ovarian cancer. Patients with previously untreated stage IIB–IV ovarian cancer were randomly assigned to six 21-day cycles of carboplatin and paclitaxel followed by either four 21-day cycles of topohttp://oncology.thelancet.com Vol 7 October 2006
tecan (n=658) or surveillance (n=650). If needed, patients could receive up to four extra cycles of carboplatin and paclitaxel, but these cycles had to be completed before topotecan began. Median progression-free survival was 18·2 months for those who received topotecan compared with 18·5 months in those who did not (hazard ratio 0·97; 95% CI 0·85–1·10) and median overall survival was 43·1 months for patients receiving the triplet treatment, compared with 44·5 months for those who did not receive topotecan (1·01; 0·86–1·18). Likewise, estimated 3-year survival did not differ between the groups (55·7% [95% CI 51·6–59·5] with topotecan, and 58·5% [54·4–62·3] without topotecan). Sequential addition of topotecan to carboplatin and paclitaxel resulted in increased haematological toxic effects and infections, with a significantly increased need in supportive care. How-
ever, no notable difference was seen in febrile neutropenia (3% vs 3%). Lead author Jacobus Pfisterer (University Hospital Mannheim, Mannheim, Germany) says that their negative results were not surprising and that no follow-up studies were being planned: “We tested a hypothesis”, he comments, “Clinical science is about waiting for results and weighing results”. “Topotecan is a good agent for recurrent ovarian cancer, but it is not going to help us effect a ‘cure’ for women with advanced stage disease”, says Beth Kaplan (CedarsSinai Medical Centre, Los Angeles, CA, USA). She thinks that researchers should instead consider studying new targeted treatments (eg, angiogenesis inhibitors, tyrosine-kinase inhibitors) as adjuncts to cytotoxic regimens.
Paula Gould 799