Near‐infrared photoimmunotherapy (NIR‐PIT) is a novel cancer therapy that employs a combination of infrared light and tumor‐targeted monoclonal antibody‐photoabsorber conjugates to cause both direct tumor necrosis and immunogenic cell death. NIR‐PIT may have potential in the perioperative setting before surgery, and therefore it is important to know the effect of NIR‐PIT on wound healing. Fifty mice were implanted with subcutaneous xenografts of N87 human gastric cancer cells, and tumors were excised after reaching a predetermined size. After excision, 30 mice were split into three groups: Controls, NIR‐PIT 1 day prior to surgery and NIR‐PIT 3 days prior to surgery. The quantity of reactive oxygen species (ROS) in each wound was measured on Postoperative Days 2 and 4, and mice were monitored weekly for 4 weeks for evidence of local tumor recurrence as well as clinical evidence of wound healing complications (eg, dehiscence, infection). The remaining 20 mice (10 controls, 10 treated with NIR‐PIT 1 day prior to surgery) were sacrificed on either Postoperative Day 7 or 14, the skin around wounds were excised, and tensile strength was measured with a digital force gauge. There were no significant differences between treatment and control groups with respect to wound ROS levels, wound tensile strength, local tumor recurrence, or postoperative complication rates (P > .05). In conclusion, neoadjuvant (pre‐operative) NIR‐PIT shows no evidence of adverse wound healing effects, and it is likely a safe adjunctive treatment to surgery. Postoperative use of NIR‐PIT merits investigation.
Near‐infrared photoimmunotherapy (NIR‐PIT), which is now under world‐wide phase 3 trial including in Japan, may be useful in the perioperative setting either before or after tumor excision that should be rational because NIR‐PIT could minimize tumor volume and initiate host antitumor immunity for safe and successful outcome. In order to apply this neoadjuvant NIR‐PIT before the surgery, only the concern of surgeons is if wound healing is hampered by preoperative NIR‐PIT. Therefore, in this study, in order to respond high demands from many surgeons, the effect of NIR‐PIT on wound healing was measured using reactive oxygen species monitoring and wound tensile strength measurements and shown to have no difference between treatment and control mice.