The serum and tissue expression of vascular endothelial growth factor-in recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is known for its recurrent relapse despite various surgical and non-surgical treatments. Vascular Endothelial growth factor (VEGF) receptor expression on tissue is reported to be raised in RRP, and anti-VEGF targeted treatment is being explored to decrease recurrences. This study aims to identify the patients most suitable for systemic anti-VEGF therapy.

The study design was a prospective cohort evaluation. The study group included all consecutive cases of RP treated surgically from November 2016-June 2019. Tissue receptor expression and serum levels of VEGF were assessed by immunohistochemistry and ELISA assay. Control samples for normal levels obtained by serum samples of healthy individuals and tissue samples obtained from healthy non-inflamed peripheral tissue of laryngectomy specimens. The tissue expression and serum levels of VEGF were compared with various disease-related factors of RP.

32 cases of RRPs were included in the study with a median age of 20.85 years (range: 3-60 years). The glottis was involved in all patients and tracheobronchial involvement was seen among 6 patients (18.75%). The systemic and tissue expression of VEGF-A was significantly higher among cases than controls (p= <0.001). The serum level of VEGF-A was significantly higher among cases with higher Derkay's score (>20) (p = 0.02) and tissue expression of VEGF-A was significantly higher in tracheobronchial RRP (p = 0.04).

Patients of RP with tracheobronchial involvement and high Derkay's score with strong tissue receptor expression & high serum level of VEGF can be identified as the patients wherein anti-VEGF monoclonal antibody treatment is more likely to be effective and merits further investigation to prove this.