ESTRO 2022 - Abstract Book

S1124

Abstract book

ESTRO 2022

Between February 2019 und August 2021 20 patients were included (17 female, 3 male) in this prospective study. Patient and tumour characteristics are displayed in Table 1. The median Follow-up was 15 (2-30) months. Distant metastases without local recurrence occured in 2 patients, both of which died. 18 patients are currently free of disease. Radiotherapy was carried out without interruptions in all patients. Chemotherapy was applied with reduced dose in 6 patients due to acute toxicity. After end of CRT dermatitis I°/II°/III° CTCAE was diagnosed in 4/11/5 patients. Diarrhea I°/II°/III° CTCAE was reported in 5/11/2 patients and fecal incontinence I°/II°/III° CTCAE in 2/3/0 patients. The overall response rate for the patient questionnaires was 95%/90%/90%/79%/88%/69% at the time of start of CRT/end of CRT/6 weeks/3 months/6 months/12 months after end of CRT. Median patient reported quality of life were 6 points (range: 1 = very poor to 7 = excellent) before the initiation of therapy, 3 points at the end of CRT and 5/6/6/6 points 6 weeks /3 Months /6 months /12 months after end of therapy.

Conclusion Our planned interim analysis shows a good compliance to the questionnaire-based assessment of quality of life before, during and after CRT. There was a significant reduction in quality of life under therapy, but also a quick recovery already 6 weeks after end of therapy.

PO-1329 Predictive factors for pathologic good response after the neoadjuvant CRT of rectal cancer

Y. Lin 1 , J. Lin 1,1 , T. Chang 1 , T. Chou 1 , L. Hung 1 , C. Huang 1

1 Changhua Christian Hospital, Radiation Oncology, Changhua City, Taiwan

Purpose or Objective For T3/T4N0 or T(any)N+ or locally unresectable rectal cancer, preoperative chemoradiation (pre-OP CRT) followed by radical resection is the standard of care. Tumor regression grade reflects the response of a tumor to neoadjuvant treatment and is the main reason behind the development of novel surgical strategies for managing patients, classified as good responders to neoadjuvant treatment . The purpose of this study is to evaluate the potential predictive factors for pathologic good response. Materials and Methods From January 2010 to December 2018, 98 patients with primary rectal cancer (without distant metastases) finished preoperative CRT, followed by radical surgery at our institution. Patients’ demographic characteristics, clinical and pathological variables, and laboratory data at baseline, during-CCRT and peri-operative, were collected by review of medical records. We divided patients into two groups, based on the AJCC tumor regression grade, by pathological finding: good responders, TRG 0-1; poor responders, TRG 2-3. Kaplan-Meier curve analysis was used to assess overall survival (OS) and progression-free survival (PFS). Logistic regression (LR) was used to evaluate those variables associated with response. Results The median age was 58 years old , male predominant (72.4%) and most (89.8%) with moderately differentiated histology. 19.4% of all patients were T2 stage (n =19), 73.5% were T3 stage (n = 72) and 7.1% were T4 stage (n=7). The median initial CEA concentration was 4.7 ng/dL. All patients completed CRT either with 50Gy in 25 fractions or with 50.4Gy in 28 fractions, to whole pelvis and pelvic lymph nodes. The neoadjuvant chemotherapy regimen included oral UFUR/ Capecitabine (n=72,