PLATELET-DERIVED ENDOTHELIAL-CELL GROWTH-FACTOR EXPRESSION CORRELATESWITH TUMOR ANGIOGENESIS AND PROGNOSIS IN NON-SMALL-CELL LUNG-CANCER

Angiogenesis is a recently described prognostic factor in nan-small-ce ll lung cancer. Platelet-derived endothelial cell growth factor (PD-EC GF), shown to be the enzyme thymidine phosphorylase (TP), induces angi ogenesis in vitro and in vivo. High intracellular levels of the enzyme are associated with increased chemosensitivity to pyrimidine antimeta bolites. PD-ECGF/TP expression was evaluated immunohistochemically in surgically resected specimens from 107 patients with operable non-smal l-cell lung cancer using the P-GF.44C monoclonal antibody. High expres sion of PD-ECGF/TP was found in 25% of cases and was associated with h igh vascular grade (P = 0.01). Fourteen of 32 (44%) high Vascular grad e tumours showed a positive reactivity for PD-ECGF/TP vs 13/75 (17%) o f low/medium Vascular grade. Positive expression was observed more fre quently in T2-staged cases than in T1 (P = 0.04). While overall surviv al was not affected (P = 0.09), subset analysis revealed that node-neg ative patients with positive PD-ECGF/TP expression had a worse prognos is (P= 0.04). The results suggest that PD-ECGF/TP may be an important molecule involved in angiogenesis in non-small-cell lung cancer. Up-re gulation of the enzyme defines a more aggressive tumour phenotype in p atients with node-negative disease. Assessment of vascular grade and P D-ECGF/TP expression should be taken into account in the design of ran domized trials assessing the role of adjuvant chemotherapy in non-smal l-cell lung cancer.