Symptom Burden Associated With Radiation Dermatitis in Breast Cancer Patients Undergoing Radiotherapy.

PURPOSE: Radiation dermatitis (RD) is a side effect experienced by many patients undergoing radiotherapy (RT) for breast cancer. In the present study, the Edmonton Symptom Assessment System (ESAS), a validated patient-reported symptom screening tool, was used to determine the impacts of RT-induced skin outcomes on ESAS items. Patient- and treatment-related factors and skin treatments to manage RD symptoms, were assessed for association with ESAS scores. METHODS: Patient and treatment characteristics were collected retrospectively for breast cancer patients treated with adjuvant RT between December 2013 and November 2015. Prospective data was collected through clinician-reported surveys. Linear regression analyses were performed to detect the relationship between patient-reported ESAS scores and clinician-reported RD symptoms. RESULTS: A total of 857 patients were included in the analysis. Moderate to severe scores were commonly reported for fatigue (n = 412, 48%), wellbeing (n = 386, 45%) and anxiety (n = 266, 31%). Oral analgesic use was associated with ESAS fatigue, drowsiness, pain, nausea, lack of appetite, shortness of breath, and wellbeing (P < .05), while dressings were only associated with anxiety (P = .02). No RD symptoms were found to be significantly associated with any ESAS items. CONCLUSIONS: The ESAS accurately reflects symptoms of fatigue, anxiety, and wellbeing for breast cancer patients undergoing RT. Our study, however, found no association between ESAS scores and RD severity, which may reflect the shortcomings of the ESAS in assessing symptom burden. Further research is necessary to warrant the development of a new site-specific symptom screening tool for use in RT for breast cancer.

Predictive factors associated with radiation dermatitis in breast cancer.

PURPOSE: Radiation dermatitis (RD) is a side effect that frequently arises during radiotherapy (RT) in breast cancer patients. The present study investigates possible predictive factors of RD, as well as the use of skin treatments to manage symptoms. METHODS: Demographic and treatment characteristics were collected retrospectively, while skin symptoms and treatments were collected prospectively for patients who received adjuvant RT between December 2013 and November 2015. Patients were seen weekly by clinicians throughout treatment, during which a clinician-reported survey was completed on RD symptoms and skin treatments. Possible predictive factors were correlated with skin outcomes through a univariate ordinal logistic regression analysis. RESULTS: A total of 1093 patients were included in this analysis. Predictive factors for erythema included dose fractionation (p<0.0001), tissue volume irradiated by tangential fields (p = 0.01), and administration of a boost (p = 0.005). High BMI (≥30 kg/m2) (p = 0.0004) and boost (p = 0.02) were predictive of edema. A dose of 50 Gy/25 (p<0.0001) and a high irradiated tissue volume (p = 0.0001) were predictive of desquamation. A dose of 50 Gy/25 (p = 0.0005) and high BMI (p = 0.02) were predictors of pain. Bolus use was the only factor associated with bleeding (p = 0.02). Patients who developed desquamation were likely to receive corticosteroids/antihistamines (p<0.0001), topical antibiotics/antifungals (p<0.001), and dressings (p<0.0001). CONCLUSION: The findings of this study provide evidence of potential predictors of RD and methods of symptom management based on symptom severity. Prevention of RD is needed among high-risk groups, such as patients with a high BMI or receiving a standard fractionation, boost, or bolus.

Do patients enrolled in observational studies have better outcomes than non-participants? A retrospective analysis.

PURPOSE: Patients are commonly enrolled into clinical trials. It has been reported that these patients may have better outcomes than those not enrolled into the study. The reasoning from these improvements could be attributable to closer follow-up, better patient adherence, more health aware patients have, or reaction to observation such as the Hawthorne effect. METHODS: Three hundred forty-six patients were approached for a prospective skin toxicity study in adjuvant breast cancer radiotherapy (RT) but declined participation between January 2018 and July 2019 (non-trial group). They were retrospectively reviewed and patient, treatment and RT-related characteristics, as well as the occurrence of skin reactions, and the usage of topical treatments were collected. This was compared with a comparison cohort of 349 patients who were enrolled into a previously conducted prospective study (trial group). RESULTS: More patients in the trial group had conventional RT (CFRT) versus hypofractionated RT (HFRT). Data was further stratified and there was no significant difference in moist desquamation, topical antibiotic usage, dressing application, home care use, topical corticoid steroid use, and oral analgesic use. There was a significantly lower pain score in the group compared with the non-trial group in both HFRT and CFRT (OR = 0.091 and OR = 0.348, p < 0.0001). CONCLUSION: Our results demonstrated no differences other than pain between the trial group and non-trial group. Therefore, in this cohort, patients enrolled into an observational trial while undergoing adjuvant breast RT demonstrated similar experiences of skin reactions. There are challenges to assessing differences between these groups, as confounding is likely. Therefore, it is recommended for future studies to additionally assess the impact of study participation on outcomes such as quality of life, quality of care received, and/or anxiety levels.

Evidence that breast tissue stiffness is associated with risk of breast cancer.

BACKGROUND: Evidence from animal models shows that tissue stiffness increases the invasion and progression of cancers, including mammary cancer. We here use measurements of the volume and the projected area of the compressed breast during mammography to derive estimates of breast tissue stiffness and examine the relationship of stiffness to risk of breast cancer. METHODS: Mammograms were used to measure the volume and projected areas of total and radiologically dense breast tissue in the unaffected breasts of 362 women with newly diagnosed breast cancer (cases) and 656 women of the same age who did not have breast cancer (controls). Measures of breast tissue volume and the projected area of the compressed breast during mammography were used to calculate the deformation of the breast during compression and, with the recorded compression force, to estimate the stiffness of breast tissue. Stiffness was compared in cases and controls, and associations with breast cancer risk examined after adjustment for other risk factors. RESULTS: After adjustment for percent mammographic density by area measurements, and other risk factors, our estimate of breast tissue stiffness was significantly associated with breast cancer (odds ratio = 1.21, 95% confidence interval = 1.03, 1.43, p = 0.02) and improved breast cancer risk prediction in models with percent mammographic density, by both area and volume measurements. CONCLUSION: An estimate of breast tissue stiffness was associated with breast cancer risk and improved risk prediction based on mammographic measures and other risk factors. Stiffness may provide an additional mechanism by which breast tissue composition is associated with risk of breast cancer and merits examination using more direct methods of measurement.

Screen-film mammographic density and breast cancer risk: a comparison of the volumetric standard mammogram form and the interactive threshold measurement methods.

BACKGROUND: Mammographic density is a strong risk factor for breast cancer, usually measured by an area-based threshold method that dichotomizes the breast area on a mammogram into dense and nondense regions. Volumetric methods of breast density measurement, such as the fully automated standard mammogram form (SMF) method that estimates the volume of dense and total breast tissue, may provide a more accurate density measurement and improve risk prediction. METHODS: In 2000-2003, a case-control study was conducted of 367 newly confirmed breast cancer cases and 661 age-matched breast cancer-free controls who underwent screen-film mammography at several centers in Toronto, Canada. Conditional logistic regression was used to estimate odds ratios of breast cancer associated with categories of mammographic density, measured with both the threshold and the SMF (version 2.2beta) methods, adjusting for breast cancer risk factors. RESULTS: Median percent density was higher in cases than in controls for the threshold method (31% versus 27%) but not for the SMF method. Higher correlations were observed between SMF and threshold measurements for breast volume/area (Spearman correlation coefficient = 0.95) than for percent density (0.68) or for absolute density (0.36). After adjustment for breast cancer risk factors, odds ratios of breast cancer in the highest compared with the lowest quintile of percent density were 2.19 (95% confidence interval, 1.28-3.72; P(t) <0.01) for the threshold method and 1.27 (95% confidence interval, 0.79-2.04; Pt = 0.32) for the SMF method. CONCLUSION: Threshold percent density is a stronger predictor of breast cancer risk than the SMF version 2.2beta method in digitized images.

Effect of scatter and an antiscatter grid on the performance of a slot-scanning digital mammography system.

The use of a grid increases perceptibility of low contrast objects in mammography. Slot-scan mammography provides a more dose efficient reduction of the scattered radiation reaching the detector than obtained with an antiscatter grid in screen-film or flat-panel digital mammography. In this paper, the potential of using a grid in a slot-scan system to provide a further reduction of scattered radiation is investigated. The components of the digital signal: primary radiation, off-focus radiation, scattered radiation, and optical fluorescence glare in a CsI(Tl) detector were quantified. Based on these measurements, the primary and scatter transmission factors (Tp, Ts), scatter-to-primary ratio (SPR), signal-difference-to-noise ratio (SDNR), and the SDNR improvement factor (K(SDNR)) were obtained. Our results showed that the SPR ranged from 0.05 to 0.19 for breast thicknesses between 2 and 8 cm, respectively. The values of K(SDNR) ranged from 0.85 to 0.94. Because the slot-scanning system has an inherently low SPR, the increase in dose required when the grid is used outweighs the benefit of the small increase in SDNR. It is possible that greater benefit could be achieved by using a grid with a higher Tp, such as obtained using air-core technology.