Background
Epidemiological studies have demonstrated a cancer-protective effect of renin-angiotensin system inhibitor (RASI) use, including reduced risk of cancer, recurrence, metastasis, and increased overall survival (OS) and cancer-specific survival (CSS). These studies have investigated the use of traditional RASIs (b-blockers, angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). A protective effect has also been observed with medications inhibiting regulatory pathways converging onto the RAS, such as metformin and cyclo-oxygenase inhibitors (COXIs). There is paucity of studies reporting the effect of these medications in head and neck cutaneous squamous cell carcinoma (HNCSCC).
Methods
All patients undergoing major head and neck surgery for HNCSCC between 1996 to 2021 at Hutt Hospital were identified from our Head and Neck Database and included. Analysis was performed for those on RASIs (ACEI, ARB, b-blocker, metformin and/or COXI), and those not taking RASIs at time of surgery. Subgroup analysis was performed based on the number of RASIs taken.
Results
Of the 350 patients included, 160 and 190 were in the non-RASI and RASI groups, respectively. There was no significant difference in recurrence-free survival (RFS) (91.7 months, 95% CI 70.3-113.1 vs 81.9 months, 95% CI 61.1-102.6, p=0.859), OS (64.9 months, 95% CI 52.6-77.1 vs 52.8 months 95% CI 43.6-62.0, p=0.167), or CSS (123 months, 95% CI 98.5-148.9 vs 115.1 months, 95% CI 94.5-135.8, p=0.446) between the non-RASI and RASi groups, respectively. There was no significant difference in RFS, OS or CSS with the number of RASIs taken.
Conclusion & Discussion
RASI use in HNCSCC patients undergoing major head and neck surgery +/- radiotherapy, is not associated with a significant improvement in RFS, OS or CSS compared to those not taking RASIs. No association was observed with number of RASIs taken, but this was limited by sample size. Further studies are warranted to explore this effect.