ESTRO 36 Abstract Book

S43 ESTRO 36 2017 _______________________________________________________________________________________________

2 and 3 respectively). Before treatment symptoms of itch (80% and 69%) and pain (67% and 58%) were present in a majority of cases in center 1 and 2, after treatment complaints were relieved completely or less severe in most patients (no or less itch 95%, no or less pain 95%). The scheme of 2x9Gy resulted in more and more severe complications, with 3x6Gy less complications were found, and using 2x6Gy even fewer and less severe complications were reported (major complication 24%, 16%, 6% p=0.046, minor complication 56%, 39%, 17% p<0.001 for center 1, 2 and 3 respectively). Conclusion We conclude that the scheme using the lowest dose of radiation seems to have a similar good outcome on recurrences as well as a lower risk on mild as well as more severe side effects, like infections, chronic wounds and apparent pigmentation differences. Our results show that when using brachytherapy a BED of 30Gy is not needed and 19Gy can be sufficient. We recommend using a lower radiation scheme, i.e. 2x6Gy, to reduce adverse events and minimize stochastic effect of this treatment. OC-0086 Perioperative interstitial high-dose-rate (HDR) brachytherapy for the treatment of recurrent keloids P. Jiang 1 , M. Geenen 2 , F.A. Siebert 1 , R. Baumann 1 , P. Niehoff 3 , D. Druecke 4 , J. Dunst 1 1 UKSH- Campus Kiel, Department of Radiation Oncology, Kiel, Germany 2 Lubinus Clinic, Department of Reconstructive Surgery, Kiel, Germany 3 University Witten-Herdecke, Department of Radiation Oncology, kiel, Germany 4 UKSH- Campus Kiel, Department of Reconstructive Surgery, Kiel, Germany Purpose or Objective Perioperative radiotherapy of keloids can reduce the risk of recurrence. Due to the wide variety of concepts the optimal treatment regime remains unclear. We established in our clinic a protocol of perioperative interstitial HDR-Brachytherapy with 3 fractions of 6 Gy and achieved an excellent local control rate of 94%. (Jiang. et. al. 2015 IJROBP). We report now an update of our long- term results of this prospective study of perioperative interstitial brachytherapy. Here we include 29 patients with a median follow-up of 5 years. Material and Methods From 2009 to 2015, 29 patients with 37 recurrent keloids were treated with perioperative interstitial HDR- brachytherapy; 3 patients had been previously treated with adjuvant external beam radiotherapy and presented with recurrences in the pretreated area. After (re-) excision the keloids, a single plastic flexible brachytherapy tube for irradiation was placed subcutaneously before closing the wound. The target volume covered the scar in total length. CT-based treatment planning was used in selected cases, e.g. if two lesions in close proximity were to be treated or for lesions in difficult anatomic locations (e.g. helix of the ear). Brachytherapy was given in three fractions with a single dose of 6 Gy in 5mm tissue depth, with the exception of one patient with a keloid on the helix who received a single dose of 6 Gy to the whole tissue. The first fraction was given within 6 hours after surgery, the other two fractions on the first postoperative day. Follow-up visits were scheduled at 6 weeks, 3 months, 6 months, 1 year, and every year thereafter. Results No procedure-related complications (e.g. secondary infections) occurred. 23 patients had keloid-related symptoms prior to treatment like pain and pruritus; disappearance of symptoms was noticed in all patients after treatment. After a median follow-up of 49,7 months (range: 7,9 to 92,7 months), 3 keloid recurrences and 2

hypertrophied scars were observed. Pigmentary abnormalities were detected in 3 patients and additional 7 patients had a mild delay in the wound healing process. Conclusion Interstitial brachytherapy is able to deliver conformal radiation exactly in the scar with extremely low exposure of other normal tissues. It is suitable to most shapes and irregular surfaces. Brachytherapy is cost-effective und can be offered in the majority of radiotherapy centers. Our three-fraction treatment schedule reduces the treatment period to two days and is therefore convenient for the patients. A radiobiological analysis of more than 2500 patients from multiple centers found a low α/β-value for local control of keloids (Flickinger et. al. 2011 IJROBP). The analysis recommended a treatment concept with few fractions and high doses per fraction delivered in a short period of time as early as possible after resection. Our results confirm it and suggest that brachytherapy may be advantageous in the management of high-risk keloids, even after failure of external beam radiotherapy. PV-0087 Improvement of models for survival prediction through inclusion of patient-reported symptoms C. Nieder 1 , T. Kämpe 1 , B. Mannsåker 1 , A. Dalhaug 1 , E. Haukland 1 1 Nordlandssykehuset HF, Dept. of Oncology and Palliative Medicine, Bodoe, Norway Purpose or Objective Widely used prognostic scores, e.g., for brain metastases and incurable lung cancer are based on disease- and patient-related factors such as extent of metastases, age and performance status (PS), which were available in the databases used to develop the scores. Few groups were able to include prospectively recorded patient-reported symptoms. In our department, all patients were assessed with the Edmonton Symptom Assessment System (ESAS, a questionnaire addressing 11 major symptoms and wellbeing on a numeric scale of 0-10) at the time of treatment planning since 2012. Therefore, we analyzed whether or not baseline symptom severity provides relevant prognostic information, which should be included during development of prognostic scores. Material and Methods A retrospective review of 112 patients treated with palliative radiotherapy (PRT) between 2012 and 2015 was performed. The patients scored their symptoms before PRT. ESAS items were dichotomized (below/above median). Uni- and multivariate analyses were performed to identify prognostic factors for survival, and from these a predictive model was developed. Results The most common tumor types were pro state (30%), breast (12%) and non-small cell lung c ancer (26%), predominantly with distant metastases. M edian survival was 8 months. Univariate analyses identified 12 factors that were associated with survival, including several ESAS items. Multivariate analysis confirmed the significance of 6 factors, from which a predictive model was developed. These were ESAS pain while not moving (median 3), ESAS appetite (median 5), ECOG PS, pleural effusion/pleural metastases, iv antibiotics during or within 2 weeks before PRT and no systemic cancer treatment. The table shows the prognostic score resulting from the multivariate model. One or two points were assigned, depending on the hazard ratio of each factor. Patients with a point sum of 0-1 had an estimated median survival of 23 months, a point sum of 2-3 8.4 months, a point sum of 4-5 4.2 months and a point sum of 6 or more 1.8 months (p=0.001). Poster Viewing : Session 2: Palliative and health services research