Fan beam computed tomography-guided online adaptive external radiotherapy for cervical cancer achieves pathological complete response: A case report.

Radiotherapy (RT) is an established viable treatment for cervical cancer across all clinical stages. However, the therapeutic ratio of conventional techniques remains suboptimal due to the anatomical proximity of the cervix to critical pelvic organs. The current study presents a case of pathological complete response (pCR) achieved exclusively through preoperative online adaptive RT (oART) guided by fan beam computed tomography (FBCT). A 54-year-old woman presenting with irregular vaginal bleeding was diagnosed with a cervical mass via pelvic imaging. Subsequent histopathological biopsy confirmed invasive papillary squamous cell carcinoma. Preoperative evaluation, supplemented by laboratory and imaging studies, ruled out distant metastases. The patient underwent fractionated oART using a CT-linear accelerator platform. Post-treatment imaging demonstrated complete resolution of the lesion, and surgical histopathology revealed no residual malignancy. This case highlights the feasibility, safety and dosimetric precision of FBCT-guided oART in cervical cancer. The pCR achieved in this case indicates that oART has the potential to improve the treatment of cervical cancer.