Laparoscopic sigmoid colectomy with primary anastomosis for experimental modeling in the nonhuman primate

Laparoscopic colon surgery is performed frequently in the clinical setting for a multitude of reasons including cancer, infection, and autoimmune disease. As a result, extensive research has been conducted in relation to clinical outcomes after surgery, but more recently, in relation to the impact of surgery and other patient factors on physiologic homeostasis including the host microbiome. Despite this, experimental surgical models for laparoscopic colon surgery are scarce in the literature with most studies utilizing rodents. While rodent studies provide valuable insights into basic mechanistic processes, the translation of novel therapeutic approaches to clinical practice often requires the use of large animal models. In exploring the intricate systems biology linking surgery and medicine, sophisticated models such as nonhuman primates (NHPs) play a pivotal role. By closely resembling human anatomical, physiological, and behavioral characteristics, NHPs facilitate the development and refinement of complex surgical techniques and peri-operative practices. Furthermore, they enable longitudinal studies that comprehensively assess both immediate and long-term outcomes. The availability and utilization of multiple robust models enhance the validity of surgical research, leading to more successful translation to human clinical practice. Here we describe our technique for performing a laparoscopic sigmoid colectomy with a primary anastomosis in an NHP. The entire procedure was well tolerated without significant ventilation or hemodynamic issue. To our knowledge, this represents the first laparoscopic sigmoid colectomy with primary anastomosis performed in an NHP. Furthermore, this demonstrates the feasibility of the technique and provides a relevant, preclinical model for the study of surgical colon disease. Although the surgical colectomy model in NHPs closely resembles the clinical scenario, it is crucial to recognize that a 'model' inherently comes with limitations. The intended use of any model should be carefully evaluated concerning the target patient population with the consideration of potential disparities in anatomy, physiology, environmental factors, and disease to properly interpret results. This model provides an opportunity to study mechanisms, from a systems biology perspective, underlying both innovative surgical treatments and their effects on diseases such as colon cancer, as well as benign conditions like inflammatory bowel disease, diverticulitis, and anastomotic leak, offering high predictive value.