Background: Radical prostatectomy, a standard management approach for localized Prostate Cancer (PC), may cause a stress response associated with immune modulating
effects. Regional anesthesia was hypothesized to reduce the immune effects of surgery by minimizing the neuroendocrine surgical stress response, thus mitigating tumor cells dissemination. Our primary objective was to investigate whether the use of spinal
blocks attenuates PC tumor cells dissemination on an animal model. We also assessed the number of circulating NK cells and the amount of inflammatory and anti-inflammatory cytokines.
Materials and methods: A subcutaneous tumor model, with PC-3M cell line transfected with a luciferase-producing gene (PC-3M-luc-C6) was used. After proper tumor establishment and before tumors became metastatic, animals were submitted to tumor excision surgeries under general or combined (general and spinal) anesthesia. A control group was only anesthetized with general anesthesia.
Results: The subcutaneous tumor model with PC-3M-luc-C6 cells was effective in
causing distant metastasis after 35 days. The number of circulating tumor cells increased in animals that underwent surgery under general anesthesia alone compared to the group submitted to combined anesthesia. Interleukin 6 levels were different in all groups, with increase in the general anesthesia group.
Conclusion: Our results suggest that combination of spinal and general anesthesia may attenuate the suppression of innate tumor immunity and it might be related to a reduction in the neuroendocrine response to surgery.
Dr. Gustavo Inoue obtained his medical degree from University of Sao Paulo Medical School and completed his residency in anesthesiology at Hospital das Clinicas of Sao Paulo (HCFMUSP). He currently works as anesthetist at private hospitals in Brazil and is a research fellow at University of Sao Paulo Medical School.
Dr. Inoue’s research interests mainly involve studying the influence of anesthesia techniques
on cancer recurrence after surgery.