ESTRO 37 Abstract book

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ESTRO 37

OC-0395 The significance of elevated SCC-Ag in squamous-cell carcinoma of uterine cervix with chemoradiation K.H. Choi 1 , S.W. Lee 1 , Y.S. Kim 1 , M. Yu 2 , S. Jeong 3 , S. Sung 4 , J.H. Lee 4 1 Seoul St. Mary's Hospital, Department of Radiation Oncology, Seoul, Korea Republic of 2 Bucheon St. Mary's Hospital, Department of Radiation Oncology, Bucheon, Korea Republic of 3 Ewha Woman's University School of Medicine, Department of Radiation Oncology, Seoul, Korea Republic of 4 St. Vincent's Hospital, Department of Radiation Oncology, Suwon, Korea Republic of Purpose or Objective Most studies in cervical cancer have set the level of Scc- Ag (squamous-cell carcinoma antigen) over 1.5-2.5 ng/mL as a significant one for poor prognosis. However, there is no definitive guideline for the significance and cut-off value for Scc-Ag in cervical cancer. Thus, we attempt to analyze the optimal cut-off value for predicting tumor recurrence and patient survival in squamous-cell carcinoma of uterine cervix. Material and Methods From January 2004 to December 2016, we enrolled cervical cancer patients staging FIGO Ib-IVa who were diagnosed as squamous-cell carcinoma and received concurrent chemoradiation and intra-cavitary radiotherapy as a radical aim in multi-institution. All patients underwent pelvic MRI and evaluated Scc-Ag before radiotherapy. The cut-off value for Scc-Ag was calculated using the Receiver Operating Characteristic curve (ROC), and the comparison for recurrence-free survival (RFS) and overall survival (OS) was performed using Kaplan-Meier method. Results A total of 309 patients were enrolled in this study. The ROC curve of Scc-Ag level was calculated for the tumor recurrence, the optimal cut-off value of Scc-Ag level was set at 4 ng/mL (sensitivity, 0.636 and specificity, 0.678, p<0.001). After median follow-up time of 31.1 months, the 3-year RFS (68.1% vs. 88.2%, p<0.001) and OS (72.1% vs. 86.8%, p=0.005) rates were significantly higher in Scc- Ag ≥ 4 ng/mL arm than in Scc-Ag < 4 ng/mL arm. The locoregional recurrence (17.6% vs. 7.0%, p=0.003), para- aortic recurrence (9.4% vs. 2.1%, p=0.014), and distant metastasis (20.4% vs. 6.9%, p=0.002) rates at 3 years were significantly different between Scc-Ag ≥ 4 ng/mL and Scc-Ag < 4 ng/mL arms. Conclusion The elevated level of Scc-Ag over 4 ng/mL is expected to be a useful predictor of tumor recurrence and patient survival in patients with squamous-cell carcinoma of uterine cervix after definitive chemoradiation. OC-0396 Late, persistent, substantial and treatment related symptoms (LAPERS): a new metric for late effects K. Tanderup 1 , R. Pötter 2 , R. Nout 3 , J. Lindegaard 4 , N. Jensen 4 , L. Fokdal 4 , A. Vittrup 4 , C. Kirisits 2 , S. Bentzen 5 , K. Kirchheiner 2 1 Aarhus University Hospital, Department of Oncology, Aarhus C, Denmark 2 Medical University of Vienna, Department of Radiation Oncology, Vienna, Austria 3 Leiden University Medical Center, Department of Radiation Oncology, Leiden, The Netherlands 4 Aarhus University Hospital, Department of Oncology, Aarhus, Denmark 5 University of Maryland School of Medicine, Department of Epidemiology and Public Health, Baltimore, USA

Purpose or Objective In longitudinal analysis of late side effects after radiotherapy, different statistical methods can be applied to summarize the outcome. Crude incidence rates, actuarial estimates and prevalence rates are well known approaches. These methods characterize specific aspects of the time-evolution of morbidity. None of these metrics capture the duration of a given symptom at the level of an individual patient. A novel approach based on a stepwise selection of patients with late, persistent, substantial and treatment-related symptoms (LAPERS) is introduced to identify patients with substantial and persisting symptoms, which are likely treatment-related. Material and Methods Patient-reported symptoms (EORTC-QLQ) were analyzed for patients enrolled in the prospective, observational, and longitudinal study on MRI image-guided, adaptive brachytherapy in locally advanced cervical cancer (EMBRACE study). Patients with at least 3 late follow up assessments (6 months and ongoing) and information at baseline and early morbidity were selected for analysis. A LAPERS event for an individual patient was defined if the median grading over late follow up observations of a given symptom was at least “Quite a bit” or “Very much” (substantial symptoms). Baseline morbidity was taken into account by requiring the median to be worse than the minimum of baseline or early assessment scoring. The LAPERS approach was applied in four relevant patient- reported symptoms on urinary and bowel function. Results Within the EMBRACE cohort, 581 out of 1416 patients (41%) fulfilled the selection criteria for this analysis. Median follow-up was 36 months (IQR 24-54). Table 1 presents the outcome, based on the different methods of reporting. The crude incidence is nearly twice as high as the highest prevalence rate. The actuarial probabilities for substantial symptoms, based on the estimation for remaining patients at risk, are around 4-5% higher than crude incidence. The proportion of patients with LAPERS events is 4-5 times lower than crude incidence, indicating that in some cases symptoms are persistent. Conclusion Many symptoms after radiotherapy are fluctuating, transient or successfully treated. Incidence methods capture the (first) occurrence of an event and cannot discriminate whether patients suffer from chronic or transient treatment-related morbidity. The novel LAPERS metric for analyzing longitudinal symptoms aims to identify patients with late, persistent, substantial and treatment-related symptoms. Expectedly, the proportion of LAPERS events is substantially lower than the well- established crude incidence, prevalence rates and actuarial estimates in cervix cancer patients after radiochemotherapy. The LAPERS estimates will be further tested and validated within the EMBRACE study and beyond, as it seems to be sensitive in terms of quantifying the proportion of patients with persistent, clinically relevant symptom burden.