ESTRO 37 Abstract book

ESTRO 37

S615

Brazil 2 University of São Paulo, Clínica Médica, Ribeirão Preto, Brazil 3 University of São Paulo, odontologia restauradora, Ribeirão Preto, Brazil Purpose or Objective To evaluate, in vitro, the effects of radiation therapy on morphological surface of enamel and dentin; the adhesive shear bond strength and bonding interface on dental substrates of permanent teeth; and the most appropriated time to restore irradiated teeth. Material and Methods Sixty third molars were cut into 120 enamel fragments and 120 dentin fragments, divided in 4 groups (n=30): G1 (control): nonirradiated, only restorative procedure; G2: restorative procedure immediately before radiotherapy (RT); G3: restorative procedure immediately after RT; G4: restorative procedure 6 months after RT. Each group was divided in 2 subgroups: SGA: Adper TM Single Bond 2; and SGB: Clearfill SE Bond. After RT and restorative procedures, the specimens were subject to confocal microscopy, shear bond strength test, and scanning electron microscopy (SEM). Results Remarkable morphological changes were observed in both substrates after a cumulative dose of 30Gy, and after 60Gy the prisms were amorphous, the interprismatic portion was degraded, and dentinal tubules are obliterated; SGB had the highest strength values, in both substrates (p<0.05) and G2 had the lowest strength values for enamel and dentin (p<0.05); in bonding interface it was possible to note that in G2 tags were rarely formed and in G3 even though the adhesive layer was thinner, tags were longer in enamel, but in dentin there were gaps formation. Conclusion RT changes substantially the morphological surface of enamel and dentin and also impairs the bonding strength and bonding interface. Clearfill system had better results than Adper Single Bond 2 and restoring the teeth before RT showed the worst results in both substrates. Clinical Significance : Nowadays the rates of cure of head and neck cancer are higher, so more patients have to live with side effects after the treatment. RT affects the dental structure and the adhesive process. So when the restorative treatment is required, the self-etch system is indicated and the definitive treatment should be done after RT. R. Benlloch Rodríguez 1 , I. Zapata Paz 1 , R. Rodríguez Romero 2 , B. Vaquero Barrón 1 , V. García Jarabo 1 , M. Sallabanda Hajro 1 , J. Romero Fernández 1 , A. De la Torre Tomas 1 , F. Valcárcel Sancho 1 1 Hospital Universitario Puerta de Hierro, Radiation oncology, Majadahonda - Madrid, Spain 2 Hospital Universitario Puerta de Hierro, Radiophysics, Majadahonda - Madrid, Spain Purpose or Objective To evaluate long-term results and toxicity in patients with Mycosis Fungoides (MF) treated with total skin electron beam irradiation (TSEBI) Material and Methods Between 1982 and 2016, a large series of 117 patients (p.) with pathologically-confirmed MF, treated with TSEBI, were retrospectively analyzed. Mean Age: 56 years PO-1091 total skin electron beam irradiation in mycosis fungoides. Long-term results

(range 26-81); Male/female 78/39; Stage: IA 26 p.(22,2%) ,IB 29 p.(24,8%), IIA 4 p.(3,4%), IIB 24 p.(20,5%), III 18 p.(15,4%), IVA 10 p.(8,5%), IVB 6p.(5,1%). A total of 97 p. (82%) received other treatment before irradiation. TSEBI was delivered using a linear accelerator; median dose: 30Gy, 4 days/week, for 6 weeks. Most patients received additional boosts (10-15 Gy) in under-dosed areas. Results Median follow-up: 27 months (range 0-348). One month after TSEBI, 49 p.(41,9%) and 16 p.(13,7 %) achieved a complete and partial response respectively. The 5-, 10- and 20-year actuarial overall survival (OS) and disease free survival for the entire group were 81%, 69% and 53%, and 34%, 25% and19% respectively. For stage, five and 10- year OS rates were: IA-IIA (86% and 77% respectively), IIB (91% and 76% respectively), III (84% and 63% respectively), IVA (56% and 0% respectively) and IVB (0% in both). Sixty-one p.(52,1%) presented relapse within a mean time of 19 months. No severe acute or chronic toxicity was seen. Conclusion TSEBI is an effective radical or palliative treatment in early and advanced disease. TSEBT provides good rates of local control and survival with tolerable acute and chronic toxicity in patients with MF. PO-1092 Weight loss and patient-reported daily activity after curative radiotherapy for head and neck cancer P.K. Møller 1 , D.G. Schmidt 1 , I. Kaalund 1 , S. Lønbro 2,3 , J. Johansen 1 1 Odense University Hospital, Department of Oncology, Odense, Denmark 2 Aarhus University Hospital, Department of Experimental Clinical Oncology, Aarhus, Denmark 3 Aarhus University, Department of Public Health- Section for Sport Science, Aarhus, Denmark Purpose or Objective Head and neck cancer (H&N) patients often experience severe side effects during and after radiotherapy, including weight loss and loss of muscle mass. This may consequently affect the level of physical activity of the patients towards an increase in immobility. The aim of this study was to investigate weight loss and how this is associated with patient-reported activity changes following curative radiotherapy. Material and Methods A total number of 45 H&N patients were included prior to curative radiation treatment (66-68 Gy/33-34 fx). The patients reported their daily and weekly activity level on a Physical Activity Scale (PAS) at the beginning of their course of radiotherapy and again 2 weeks after the final treatment. The PAS questionnaire collected information on daily or weekly duration of activity assessed within nine intensity levels including sleep. Patient replies were combined with weekly weight registrations performed by radiotherapists during treatment. Results Six patients were excluded, only returning the baseline PAS questionnaire. This left 39 patients (32 men and 7 women) for analysis. The mean age was 56.5 (range 33- 78). At the end of follow-up, the mean weight loss was 5.3 kg (SD 4.6) and 54% had a weight loss above 5% of their baseline weight (mean 6.4%, SD 5.5). Weight loss varied from a 6% weight gain to a 17.9% weight loss. The majority of the patients (77%) reported not participating in any kind of physical exercise on a weekly basis pre-