ESTRO 2024 - Abstract Book

S2214

Clinical - Upper GI

ESTRO 2024

combined with adenocarcinoma of the EG junction. There were 37 esophageal cancers alone, 18 synchronous esophageal cancer and squamous cell carcinoma of the head/neck, and 6 metachronous esophageal cancers (2 oral cavity, 1 oropharynx, 1 thyroid, 1 prostate, and 1 liver cancer). The IndCT regimen consists of weekly ME-P-FL (methotrexate + epirubicin, cisplatin, 5-fluouracil + leucovorin) with/without taxanes (docetaxel or paclitaxel) for 12 weeks, followed by IMRT 50.4 Gy/28 fractions plus concurrent monthly cisplatin + 5-fluouracil or weekly cisplatin.

Results:

Fifty-three of 61 (86.9%) patients can complete the planned IndCT and 80.3% of patients finish the CCRT/RT. The overall response rate to IndCT is 92.7% (complete response 35%) for evaluable patients. The most common grade 3/4 toxicities were neutropenia (53.9%), leucopenia (38.4%), anemia (19.2%), and thrombocytopenia (9.6%) during IndCT phase. Sixteen patients received esophagectomy after the whole chemoradiotherapy and pathological complete response were observed in 7 patients (43.8%). In addition, 4 patients had residual tumor foci of less than 5 mm. After a short follow-up (median 16 months), the 1-year and 2-year overall survival (OS) rates are 79.8% and 60.3%, respectively. Univariate analyses revealed that initial presentation of distant metastasis (yes vs. no, P=0.020), advanced T-stage (T3-4 vs T1-2, P=0.050), pretreatment low serum albumin (< vs. > 3.5, P<0.001), high neutrophil/lymphocyte ratio (> vs < 4, P=0.038), IndCT with no taxanes (vs. taxanes-containing regimen, P=0.032), single esophageal cancer (vs. synchronous/metachronous esophageal cancer, P=0.015) predict worse OS. The other variables (age, gender, N-stage, response to IndCT, esophagectomy or not, initial weight loss, pretreatment serum markers of LDH, SCC, CEA, and BMI showed no significant impact on survival.

Conclusion:

Preliminary results of our IndCT followed by CCRT/RT are feasible for esophageal cancer with encouraging preliminary outcome. This novel protocol deserves to study in future trials to compare with the standard neoadjuvant CCRT followed by surgery.

Keywords: esophageal cancer, chemotherapy, radiotherapy

1912

Digital Poster

CBCT-based online adaptive radiotherapy of esophageal cancer: first clinical experiences

Nicolas Bachmann 1 , Daniel Schmidhalter 2 , Frédéric Corminboeuf 2 , Manser Peter 2 , Ekin Ermis 1 , Daniel M. Aebersold 1 , Hossein Hemmatazad 1 1 Bern University Hospital (Inselspital), Radiation Oncology, Bern, Switzerland. 2 Bern University Hospital (Inselspital), Division of Medical Radiation Physics and Department of Radiation Oncology, Bern, Switzerland

Purpose/Objective: