ESTRO meets Asia 2024 - Abstract Book

S206

Interdisciplinary – Lower GI

ESTRO meets Asia 2024

Keywords: radiotherapy, bifidobacterium longum

261

Digital Poster

High rate of Dropping from follow-up hinders implementing rectal cancer organ preservation protocols

Basma MBAREK 1 , THAO VO 1 , TIN PHANG DUC 2

1 oncology, FV HOSPITAL, HCMC, Vietnam. 2 oncology, FV HOSPITAL, hcmc, Vietnam

Purpose/Objective:

Radiotherapy as neoadjuvant treatment for rectal cancer has been a standard of care for locally advanced disease and node positive stages. This treatment improves local control and relapse free survival but did not impact the overall survival.. Recent data from trials have suggested the possibility in selected cases to omit surgery and follow up patients that present with a complete radiological, endoscopic and clinical response. The NCCN guidelines have made the total neoadjuvant treatment (TNT) by chemotherapy and radiotherapy followed by watchful follow up with clinical and endoscopic examination, MRI imaging and biopsy, the new standard of care

Material/Methods:

In our single institution experience, total neoadjuvant treatment as per the experimental arm of RAPIDO trial or PRODIGE 23 trial was suggested to patients with low rectum disease staged T3T4N0 or T any N1 N2 (1,2) starting from January 2022 . An audit of this newly implemented treatment strategy was done in June 2023 to evaluate its suitability to our treated population. Patient selection, family and patient education, The rate of response among patients, dose density and adherence to treatments, as well as the adherence to the guidelines of follow up after complete response were evaluated.

Results:

Total number of patients treated for rectum cancer between January 2022 and June 2023 was 86 patients among which 21 patients (20%) presented with low rectum cancer eligible to TNT treatment. Among the 21 patients with low rectum tumors treated by TNT 40% were female and 60 % were male patients, aged from 28 to 72 years old. Only 5 % had no node involvement (T4N0) and 95% of patients had node involvement (N1 or N2) all patients were M0 . The internal audit of protocol implementation has revealed that all patients had a traceable and signed patient and family education that included treatment protocol, possible side effects as well as follow up guidelines in case of organ preservation. Patient ability to learn, as evaluated by the attending oncologist ranged from average to excellent. Dose density of chemotherapy was acceptable and median number of delayed cycles per patient was less than 1 cycle and there was no interruption in radiotherapy treatment. The outcome of treatment was evaluated by digital examination , MRI and endoscopy in 100% of patients and biopsy was performed in 35% of patients. Complete response was achieved in 6 patients out of 21 patients with low rectum cancer (28,6%), near complete response in 3 patients (14%) and incomplete response in 12 patients (57%) no cases of progression were reported. Among the 6 patients that have achieved a complete radiological, endoscopic and pathological response. 5 patients dropped from regular follow up and were lost from surveillance. The mean duration of adherence to follow up was 5,5 months. Most of the patients dropped follow up after the first consultation. Only 1 patient has continued follow up as per guidelines and has presented with tumor progression and was operated 9 months