Case Report:Anal Sphincter-Sparing Surgery for Ultra-Low Rectal Cancer Using Robotic Assistance After Photodynamic Therapy Combined with Systemic Treatment

The incidence of low rectal cancer accounts for more than 50% of all rectal cancer cases in China, and many patients decline colostomy. Conversion or neoadjuvant therapy is often necessary to facilitate surgical intervention and enhance efficacy. The combination of photodynamic therapy and systemic therapy, aided by robotic assistance, has the potential to improve the success rate of surgeries for low rectal cancer. This treatment approach has not been previously reported. We present a case of ultra-low rectal cancer located 2 cm from the anus, staged as T4N1Mx at the time of diagnosis. The patient underwent one cycle of photodynamic therapy combined with four cycles of systemic therapy, resulting in successful transformation. Subsequently, low sphincter-preserving surgery was performed with robotic assistance, significantly enhancing the quality of life for this patient with advanced low rectal cancer.