Urinary epidermal growth factor (EGF) levels and epidermal growth factor receptor (EGF-R) expression in human cerebral tumors. Clinical considerations

The levels of Epidermal Growth Factor (EGF) in urine samples collected from 58 patients (22 low grade gliomas, 13 anaplastic gliomas, 15 glioblastomas and 8 meningiomas) with cerebral tumors admitted at our Institute during 1994 were determined. EGF levels were measured by a specific RIA method. A preoperative and one or two postoperative determinations were performed. Further samples were collected before and at three weeks after postoperative radiotherapy and/or chemotherapy. EGF-Receptor (EGF-R) was determined by an immunohistochemical method on specimens of the same tumor. Preoperative levels showed a positive correlation with the degree of tumor anaplasia. A decrease of the postoperative levels of EGF was observed in all patients who underwent surgery and the entity of the decrease seemed to be well correlated with the extent of the tumoral resection. A strict correlation between EGF levels fluctuations and clinical and neuroradiological features was documented in patients submitted to radiotherapy and/or chemotherapy. The preliminary results on EGF-R expression suggest the existence of a correlation between EGF levels and the receptor expression. In 4 cases of glioblastoma low preoperative levels were associated to an high receptor expression in 2 cases while in the remainder the receptor was not detectable. An high receptor expression is pathognomonic of meningiomatous tissue, even if is not correlated to the biological behaviour and histological features of the neoplasia. These preliminary data suggest the reliability of EGF levels/EGF-R determination in the diagnosis and follow-up of patients with cerebral tumors particularly for those of glial origin. Our data confirmed the role of the EGF system in the development and growth of human gliomas and meningiomas.