ESTRO 2023 - Abstract Book

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ESTRO 2023

Figure 1.

Conclusion In our experience, improved LC using high BED in non-heavily pretreated patients was correlated to reduced risk of IHR and to improved OS. IHR was the most common mode of failure in patients treated with SBRT for LM and was correlated with further extrahepatic progression. Our findings suggest that IHR may result from uncontrolled macroscopic LM rather than ubiquitous micrometastatic dissemination, and preceed further systemic spread at distant sites. Our findings support the use of SBRT as an efficient tool to block stepwise metastatic spread from uncontrolled isolated LM to liver, and from liver to distant site, thus extending global disease control.

PO-1355 Impact of lymphopenia in patients with esophageal cancer after neoadjuvant chemoradiotherapy

N. SLIM 1 , C. Chissotti 1 , P. Passoni 2 , R. Tummineri 1 , F. Zerbetto 1 , M. Torrisi 1 , L. Giannini 1 , M. Midulla 1 , F. Ferrario 1 , S. Villa 1 , E. Mazza 3 , L. Albarello 4 , F. De Cobelli 5 , R. Rosati 6 , S. Cascinu 3 , N.G. Di Muzio 7 1 IRCCS, San Raffaele Scientific Institute, Radiation Oncology, Milano, Italy; 2 IRCCS, San Raffaele Scientific Institute , Radiation Oncology, Milano, Italy; 3 IRCCS, San Raffaele Scientific Institute, Medical Oncology, Milano, Italy; 4 IRCCS, San Raffaele Scientific Institute, Pathological Anatomy, Milano, Italy; 5 IRCCS, San Raffaele Scientific Institute, Radiology, Milano, Italy; 6 IRCCS, San Raffaele Scientific Institute, Surgery, Milano, Italy; 7 IRCCS, San Raffaele Scientific Institute; University Vita-Salute san Raffaele, Radiation Oncology, Milano, Italy Purpose or Objective Predictive value of lymphopenia in patients (pts) with esophageal cancer (EC) is unclear, high grade of lymphopenia seems to be associated with worse prognosis. We evaluated the impact of lymphopenia on outcomes in our pts with EC and esophageal gastric junction cancer (EGJC) treated with neoadjuvant chemoradiotherapy. Materials and Methods from April 2014 to September 2022, 99 pts (F: 20; M:79), with histologically proven EC or EGJC were treated according to CROSS study. Radiotherapy (RT) consisted in 41.4 Gy/23 fr concomitant to weekly chemotherapy (ChT) with carboplatin and paclitaxel. Median age of pts was 64 y (29-80), median KPS was 90 (80-100). Fifty-six pts (57%) had adenocarcinoma, 42 pts (42%) squamous cell carcinoma and 1 pt (1%) adeno-squamous carcinoma. All pts underwent CT/PET simulation, repeated for restaging. Acute toxicity was assessed by CTCAE v 5.0. Results clinical stage was T1 in 4 pts, T2 in 22 pts, T3 in 69 pts, T4 in 4 pts, N0 in 25 pts and N+ in 74 pts. Tumor site was: proximal in 6 pts, middle third in 23 pts, distal third in 41 pts and EGJ in 29 pts. Median tumor length was 5 cm (1-15). Radiotherapy