1. ¹3rd Department of Respiratory Medicine, Sismanogleiou Hospital, Sismanogleiou 1, PC 15126 Athens, Greece
2. ²ICRF Medical Statistics Group, Centre for Statistics in Medicine, Institute of Health Sciences, Old Road, Headington, Oxford OX3 7LF, UK
3. ³Department of Histopathology, University College London, Rockefeller Building, University Street, London WC1E 6JJ, UK
4. ⁴Division of Thoracic Surgery, Universita' Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Roma, Italy
5. ⁵Department of Histopathology, Royal Brompton, Hospital, Sydney Street, London SW3 6NP, UK
6. ⁶Department of Thoracic Surgery, Royal Brompton, Hospital, Sydney Street, London SW3 6NP, UK
7. ⁷Centre for Cutaneous Research, Barts and the London, Queen Mary's School of Medicine and Dentistry, 2 Newark St, London E1 2AT, UK
8. ⁸ICRF Medical Oncology Unit, Churchill Hospital, Old Road, Headington, Oxford OX3 9LJ, UK
9. ⁹ICRF Tumour Pathology Group, Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK

Correspondence: F Pezzella, E-mail: f.pezzella@icrf.icnet.uk

Received 20 June 2001; Revised 9 October 2001; Accepted 15 October 2001.

Abstract

We have previously described a group of non-small cell lung carcinomas without morphological evidence of neo-angiogenesis. In these tumours neoplastic cells fill up the alveoli and the only vessels present appear to belong to the trapped alveolar septa. In the present study we have characterised the phenotype of the vessels present in these non-angiogenic tumours, in normal lung and in angiogenic non-small cell lung carcinomas. The vessels, identified by the expression of CD31, were scored as mature when expressing the epitope LH39 in the basal membrane and as newly formed when expressing V3 on the endothelial cells and/or lacking LH39 expression. In the nine putative non-angiogenic cases examined, the vascular phenotype of all the vessels was the same as that of alveolar vessels in normal lung: LH39 positive and V3 variable or negative. Instead in 104 angiogenic tumours examined, only a minority of vessels (mean 13.1%; range 0–60%) expressed LH39, while V3 (in 45 cases) was strongly expressed on many vessels (mean 55.5%; range 5–90%). We conclude that in putative non-angiogenic tumours the vascular phenotype is that of normal vessels and there is no neo-angiogenesis. This type of cancer may be resistant to some anti-angiogenic therapy and different strategies need to be developed.