Robin S. Macherey

Bio: Robin S. Macherey is an academic researcher from Allegheny General Hospital. The author has contributed to research in topics: Lung cancer & Survival rate. The author has an hindex of 9, co-authored 10 publications receiving 947 citations. Previous affiliations of Robin S. Macherey include The Chinese University of Hong Kong & Allegheny College.

Vascular endothelial growth factor expression in stage I non-small cell lung cancer correlates with neoangiogenesis and a poor prognosis.

Abstract: Background: Vascular endothelial growth factor (VEGF) plays an important role in tumor growth and metastasis. We investigated the prognostic significance of VEGF overexpression, intratumoral microvessel density (MVD), and angiolymphatic invasion in stage Ia-b non-small cell lung cancer (NSCLC). Methods: Eighty-five patients undergoing complete surgical resection of pathologic stage Ia-b NSCLC were evaluated. The mean and median clinical follow-up were 37.1 and 39.0 months (range, 30–44 months), respectively. Paraffin-embedded tumor specimens were stained with VEGF and CD31 (a specific endothelial marker) using immunohistochemical methods. VEGF staining was evaluated, by combining both percentage of positive tumor cells and staining intensity, as low (negative and 20% of tumor cells showing strong positivity). CD31 staining was expressed as MVD per high power field at 400× magnification. Angiolymphatic invasion was expressed as either presence or absence. Results: Low VEGF expression was seen in 25 (29%) patients, and high VEGF expression was seen in 60 (71%) patients. The survival rate in patients with low VEGF expression was significantly higher (80%) than that in those with high VEGF expression (48%, P = .018). The mean MVD in the low VEGF group was 23.7 ± 5.7 vs. 34.4 ± 9.3 in the high VEGF group (P = .001). Patients with high MVD also had a significantly lower survival rate than did those with low MVD count (46% vs. 73%, P = .0053). Age, sex, tumor type, and tumor differentiation were not found to be associated with overall survival. The presence of angiolymphatic invasion and T2 stage (i.e., tumor size > 3 cm) were associated with decreased survival. High VEGF expression, tumor size, and angiolymphatic invasion emerged as three independent factors predicting worsening prognosis using multivariate analysis. Conclusion: High VEGF expression within stage I NSCLC is closely associated with high intratumoral angiogenesis and poor prognosis. Immunohistochemical evaluation of T stage and VEGF expression along with examination of angiolymphatic invasion perioperatively may aid in predicting prognosis. Adjuvant therapies aimed at retarding tumor angiogenesis may be considered for stage I NSCLC patients with high VEGF levels.

Clinical Application of Antiangiogenic Therapy: Microvessel Density, What It Does and Doesn't Tell Us

Abstract: A substantial number of clinical trials using antiangiogenic therapies are ongoing worldwide. How to achieve the maximum benefit from these therapies and how to monitor patient response are of paramount concern to investigators. There are currently no markers of the net angiogenic activity of a tumor available to aid investigators in the design of antiangiogenic treatment schemes. It stands to reason that quantification of various aspects of tumor vasculature might provide an indication of angiogenic activity. One often-quantified aspect of tumor vasculature is microvessel density. Studies over the last decade have demonstrated the value of using tumor microvessel density as a prognostic indicator for a wide range of cancers. In this context, measurement of microvessel density facilitates assessments of disease stage and the likelihood of recurrence and helps guide treatment decisions. Recently, however, it has been assumed by some investigators that measurements of microvessel density may also reveal the degree of angiogenic activity in a tumor. Based on this assumption, quantification of microvessel density is thought to constitute a surrogate marker for the efficacy of antiangiogenic agents as well as a means by which to assess which patients are good candidates for antiangiogenic therapy prior to treatment. Here we contend that, although microvessel density is a useful prognostic marker, it is not, by itself, an indicator of therapeutic efficacy, nor should it be used to guide the stratification of patients for therapeutic trials. In this review, we discuss the evidence for these assertions and what can and cannot be determined from measurements of microvessel density.

ERS/ESTS clinical guidelines on fitness for radical therapy in lung cancer patients (surgery and chemo-radiotherapy)

Abstract: A collaboration of multidisciplinary experts on the functional evaluation of lung cancer patients has been facilitated by the European Respiratory Society (ERS) and the European Society of Thoracic Surgery (ESTS), in order to draw up recommendations and provide clinicians with clear, up-to-date guidelines on fitness for surgery and chemo-radiotherapy. The subject was divided into different topics, which were then assigned to at least two experts. The authors searched the literature according to their own strategies, with no central literature review being performed. The draft reports written by the experts on each topic were reviewed, discussed and voted on by the entire expert panel. The evidence supporting each recommendation was summarised, and graded as described by the Scottish Intercollegiate Guidelines Network Grading Review Group. Clinical practice guidelines were generated and finalized in a functional algorithm for risk stratification of the lung resection candidates, emphasising cardiological evaluation, forced expiratory volume in 1 s, systematic carbon monoxide lung diffusion capacity and exercise testing. Contrary to lung resection, for which the scientific evidences are more robust, we were unable to recommend any specific test, cut-off value, or algorithm before chemo-radiotherapy due to the lack of data. We recommend that lung cancer patients should be managed in specialised settings by multidisciplinary teams.