Quantitative assessments of late radiation-induced skin and soft tissue toxicity and correlation with RTOG scales and biological equivalent dose in breast cancer

Data de publicació electrònica: 18-11-2021Purpose: Radiation-induced toxicity (RIT) is usually assessed by inspection and palpation. Due to their subjective and unquantitative nature, objective methods are required. This study aimed to determine whether a quantitative tool is able to assess RIT and establish an underlying BED-response relationship in breast cancer. Methods: Patients following seven different breast radiation protocols were recruited to this study for RIT assessment with qualitative and quantitative examination. The biologically equivalent dose (BED) was used to directly compare different radiation regimens. RIT was subjectively evaluated by physicians using the Radiation Therapy Oncology Group (RTOG) late toxicity scores. Simultaneously an objective multiprobe device was also used to quantitatively assess late RIT in terms of erythema, hyperpigmentation, elasticity and skin hydration. Results: In 194 patients, in terms of the objective measurements, treated breasts showed higher erythema and hyperpigmentation and lower elasticity and hydration than untreated breasts (p < 0.001, p < 0.001, p < 0.001, p = 0.019, respectively). As the BED increased, Δerythema and Δpigmentation gradually increased as well (p = 0.006 and p = 0.002, respectively). Regarding the clinical assessment, the increase in BED resulted in a higher RTOG toxicity grade (p < 0.001). Quantitative assessments were consistent with RTOG scores. As the RTOG toxicity grade increased, the erythema and pigmentation values increased, and the elasticity index decreased (p < 0.001, p = 0.016, p = 0.005, respectively). Conclusions: The multiprobe device can be a sensitive and simple tool for research purpose and quantitatively assessing RIT in patients undergoing radiotherapy for breast cancer. Physician-assessed toxicity scores and objective measurements revealed that the BED was positively associated with the severity of RIT

International radiation oncology trainee decision making in the management of radiotherapy-induced nausea and vomiting

Purpose: This study explored international radiation oncology trainee decision making in the management of radiotherapy-induced nausea and vomiting (RINV). Methods: Radiation oncology trainees who were members of the national radiation oncology associations of the USA, Canada, Netherlands, Australia, New Zealand, France, Spain and Singapore completed a Web-based survey. Respondents estimated the risks of nausea and vomiting associated with six standardised radiotherapy-only clinical case vignettes modelled after international anti-emetic guidelines and then committed to prophylactic, rescue or no therapy as an initial management approach for each case. Results: One hundred and seventy-six trainees from 11 countries responded. Only 28 % were aware of any anti-emetic guideline. In general, risk estimates and management approaches for the high-risk and minimal risk cases varied less and were more in line with guideline standards than were estimates and approaches for the moderate- and low-risk cases. Prophylactic therapy was the most common approach for the high-risk and a moderate-risk case (83 and 71 % of respondents respectively), while rescue therapy was the most common approach for a second moderate-risk case (69 %), two low-risk cases (69 and 76 %) and a minimal risk case (68 %). A serotonin receptor antagonist was the most commonly recommended prophylactic agent. On multivariate analysis, a higher estimated risk of nausea predicted for recommending prophylactic therapy, and a lower estimated risk of nausea predicted for recommending rescue therapy. Conclusions: Radiation oncology trainee risk estimates and recommended management approaches for RINV clinical case vignettes varied and matched guideline standards more often for high-risk and minimal risk cases than for moderate- and low-risk cases. Risk estimates of nausea specifically were strong predictors of management decisions

Association between single-nucleotide polymorphisms in DNA double-strand break repair genes and prostate cancer aggressiveness in the Spanish population.

Novel predictors of prognosis and treatment response for prostate cancer (PCa) are required to better individualize treatment. Single-nucleotide polymorphisms (SNPs) in four genes directly (XRCC5 (X-ray repair complementing defective repair in Chinese hamster cells 5) and XRCC6 (X-ray repair complementing defective repair in Chinese hamster cells 6)) or indirectly (PARP1 and major vault protein (MVP)) involved in non-homologous end joining were examined in 494 Spanish PCa patients. A total of 22 SNPs were genotyped in a Biotrove OpenArray NT Cycler. Clinical tumor stage, diagnostic PSA serum levels and Gleason score at diagnosis were obtained for all participants. Genotypic and allelic frequencies were determined using the web-based environment SNPator. (XRCC6) rs2267437 appeared as a risk factor for developing more aggressive PCa tumors. Those patients carrying the GG genotype were at higher risk of developing bigger tumors (odds ratio (OR)=2.04, 95% confidence interval (CI) 1.26-3.29, P=0.004), present higher diagnostic PSA levels (OR=2.12, 95% CI 1.19-3.78, P=0.011), higher Gleason score (OR=1.65, 95% CI 1.01-2.68, P=0.044) and D'Amico higher risk tumors (OR=2.38, 95% CI 1.24-4.58, P=0.009) than those patients carrying the CC/CG genotypes. Those patients carrying the (MVP) rs3815824 TT genotype were at higher risk of presenting higher diagnostic PSA levels (OR=4.74, 95% CI 1.40-16.07, P=0.013) than those patients carrying the CC genotype. When both SNPs were analyzed in combination, those patients carrying the risk genotypes were at higher risk of developing D'Amico higher risk tumors (OR=3.33, 95% CI 1.56-7.17, P=0.002). We believe that for the first time, genetic variants at XRCC6 and MVP genes are associated with risk of more aggressive disease, and would be taken into account when assessing the malignancy of PCa