Measurement of 6-MV X-ray surface dose when topical agents are applied prior to external beam irradiation

Prophylaxis of Radiation-Induced Dermatitis in Patients With Breast Cancer Using Herbal Creams: A Prospective Randomized Controlled Trial

Radiation-induced toxicity is a major limiting factor for prescribing radiation dose in cancer radiotherapy. Skin reaction to radiation is one of the primary concerns, which could affect quality of life of the patients both physically and mentally. Reviews of the literature show limited number of effective reagents for its prophylaxis. In this study, we attempted to determine whether prophylactic treatment of the 3 different herbal creams containing Centella asiatica, Cucumis sativus, and Thunbergia laurifolia extracts as well as a commercial moisturizing cream could reduce acute skin reaction in breast cancer patients undergoing radiotherapy. A total of 153 breast cancer patients undergoing radiotherapy were randomly assigned into 5 different groups with one group receiving no treatment. The patients were instructed to apply their designated creams once daily from their first radiotherapy session until 1-month post-irradiation. Their skins were graded by a radiation oncologist on a weekly basis until 1-month post-irradiation to identify any skin reactions. The results showed that the administration of the herbal creams or the moisturizing cream could neither reduce the severity nor delay the onset of dermatitis compared with the no treatment group. However, despite the limited benefits from the prophylaxis, the Cucumis sativus cream was shown to help with the skin recovery post-irradiation. These results suggested that breast cancer patients undergoing radiotherapy should be advised to apply moisturizing cream to the area of irradiated skin.

Assessing the Validity of Clinician Advice That Patients Avoid Use of Topical Agents Before Daily Radiotherapy Treatments

Importance

Radiation dermatitis is common and often treated with topical therapy. Patients are typically advised to avoid topical agents for several hours before daily radiotherapy (RT) out of concern that topical agents might increase the radiation dose to the skin. With modern RT's improved skin-sparing properties, this recommendation may be irrelevant.

Objective

To assess whether applying either metallic or nonmetallic topical agents before radiation treatment alters the skin dose.

Design, Setting, and Participants

A 24-question online survey of patients and clinicians was conducted from January 15, 2015, to March 15, 2017, to determine current practices regarding topical therapy use. In preclinical studies, dosimetric effect of the topical agents was evaluated by delivering 200 monitor units and measuring the dose at the surface and at 2-cm depth in a tissue-equivalent phantom with or without 2 common topical agents: a petroleum-based ointment (Aquaphor, petrolatum 41%) and silver sulfadiazine cream, 1%. Skin doses associated with various photon and electron energies, topical agent thicknesses, and beam incidence were assessed. Whether topical agents altered the skin dose was also evaluated in 24 C57BL/6 mice by using phosphorylated histone (γ-H2AX) immunofluorescent staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Preclinical studies took place at the University of Pennsylvania.

Main Outcomes and Measures

Patient and clinician survey responses; surface radiation dose readings in tissue-equivalent phantom; and γ-H2AX and TUNEL intensity measured in mice.

Results

The 133 patients surveyed received RT for cancer and had a median (range) age of 60 (18-86) years; 117 (87.9%) were women. One hundred eight clinicians completed the survey with 105 reporting that they were involved in managing patient skin care during RT. One hundred eleven (83.4%) of the patients and 96 (91.4%) of the 105 clinicians received or gave the advice to avoid applying topical agents before RT treatments. Dosimetric measurements showed no difference in the delivered dose at either the surface or a 2-cm depth with or without a 1- to 2-mm application of either topical agent when using en face 6- or 15-megavoltage (MV) photons. The same application of topicals did not alter the surface dose as a function of beam incident angle from 15° to 60°, except for a 6% increase at 60° with the silver sulfadiazine cream. Surface dose for 6- and 15-MV beams were significantly increased with a thicker (≥3-mm) topical application. For 6 MV, the surface dose was 1.05 Gy with a thick layer of petroleum-based ointment and 1.02 Gy for silver sulfadiazine cream vs 0.88 Gy without topical agents. For 15 MV, the doses were 0.70 Gy for a thick layer of petroleum-based ointment and 0.60 Gy for silver sulfadiazine cream vs 0.52 Gy for the controls. With 6- and 9-MeV electrons, there was a 2% to 5% increase in surface dose with the use of the topical agents. There were no dose differences at 2-cm depth. Irradiated skin in mice showed no differences in γ-H2AX-positive foci or in TUNEL staining with or without topical agents of varying thickness.

Conclusions and Relevance

Thin or moderately applied topical agents, even if applied just before RT, may have minimal influence on skin dose regardless of beam energy or beam incidence. The findings of this study suggest that applying very thick amounts of a topical agent before RT may increase the surface dose and should be avoided.

Effect of metal-containing topical agents on surface doses received during external irradiation

The ability of topical metal-containing agents (MCAs) to enhance radiation dermatitis remains controversial. In the present study, we evaluated increases in surface doses associated with topical agents at different application thicknesses and with MCAs versus non-metal containing agents (NMCAs). We assessed two clinically available MCAs, zinc oxide ointment (ZOO) and silver sulfadiazine cream (SSDC), and eight NMCAs. Surface doses were measured using a Markus chamber placed on a polystyrene phantom. To evaluate the role of application thickness, each agent was applied to the chamber in oil-slick (<0.1-mm), 1-mm and 5-mm layers prior to irradiation of a 10 × 10 cm field with 4-, 6- and 10-MV X-ray beams. The surface dose enhancement ratio (SDER) was calculated as the ratio of the surface dose with an agent to the dose without an agent. The SDER values for the eight NMCAs, ZOO and SSDC at an oil-slick thickness were 101.6-104.6% (mean: 103.3%), 104.5% and 105.0%, respectively, using a 6-MV X-ray beam. The corresponding values at a 1-mm thickness were 196.8-237.8% (mean: 215.7%), 229.3% and 201.4%, respectively, and those at a 5-mm thickness were 342.2-382.4% (mean: 357.9%), 357.1% and 352.6%, respectively. A similar tendency was found using 4- and 10-MV X-ray beams. The lack of a significant difference in surface dose enhancement between MCAs and NMCAs, particularly when applied in oil-slick layers, suggests that MCAs do not need to be avoided or applied in a restricted manner during radiotherapy for dosimetric reasons.

A Canadian Survey of the Management of Radiation-Induced Skin Reactions

INTRODUCTION

Radiation therapy skin reactions are one of the most common side effects and can cause patient distress. In some cases, a severe radiation-induced skin reaction may limit delivered dose and potentially compromise treatment outcomes. There are some established best practices, but approaches and patient advice appear to have changed little over the years and are often based on tradition, not evidence. Canadian radiation therapy departments use different skin care products and approaches, and there has been little previous work to examine national practice patterns.

MATERIALS AND METHODS

This study used a 42-item electronic survey based on a questionnaire designed by the UK Society and College of Radiographers. Practice data were collected related to assessment and prophylactics, interventions for prevention and management, and use of tools and guidelines. The final survey version was distributed to an identified radiation therapist-registered nurse dyad at each radiation therapy department in Canada (n = 44).

RESULTS

Thirty-three departments responded (75% response rate). Results suggest a variation in national management. A number of departments continue to advise patients not to wash or use deodorant/antiperspirant despite having evidence to the contrary. There are also unnecessary restrictions on the use and timing of application of lotions as well as conflicting postradiotherapy skin care instructions regarding sun exposure.

CONCLUSION

The study demonstrated variation in practice across Canadian radiation therapy departments. National interprofessional guidelines could improve uptake of best practices. Where there is little evidence, a stress-reduction approach with more collaborative decision-making should be used to minimize patient disruption.

Avoiding antiperspirants during breast radiation therapy: Myth or sound advice?

Breast cancer patients are typically advised to avoid antiperspirants for fear of increasing radiation dermatitis in the axilla. We hypothesized that antiperspirants would have minimal effect on skin dose. We found no difference in surface dose±antiperspirants using 6MV photons at gantry angles of 0°/30°/60°/90° regardless of aluminum concentration.

Acute radiation dermatitis in breast cancer patients: challenges and solutions

Nearly all women who receive radiotherapy (RT) for breast cancer experience some degree of radiation dermatitis. However, evidence describing the appropriate management of radiation dermatitis is often lacking or contradictory. Here, we summarize the available literature regarding radiation dermatitis causes, the presentation and timing of symptoms, methods for dermatitis assessment and prevention, and review evidence-based management strategies.

Dosimetric impacts on skin toxicity for patients using topical agents and dressings during radiotherapy

Background and purpose

Skin care practices for radiotherapy patients are complicated by dosimetric concerns. This study measures the effect on skin dose of various topical agents and dressings.

Materials and methods

Superficial doses were measured under 17 topical agents and dressings and three clinical materials for reference. Dose was measured using a MOSFET detector under a 1 mm polymethyl methacrylate slab, with 6 MV photon beams at 100 cm source to surface distance.

Results

Relative skin dose under reference materials was 128% (thermoplastic mask), 158% (5 mm bolus) and 171% (10 mm bolus). Under a realistic application of topical agent (0·5 mm), relative skin doses were 106–111%. All dry dressings yielded relative dose of ≤111%; two wet dressings yielded higher relative doses (133 and 141%).

Conclusions

Under clinically relevant conditions, no cream, gel or dry dressing increased the skin dose beyond that seen with a thermoplastic mask. Dressings soaked with water produced less skin dose than 5 mm bolus. This may be unacceptable if wet dressings are in place for the majority of the treatment course. Our results suggest that skin care practices should not be limited by dosimetric concerns when using a 6 MV photon beam.

The effect of silver sulfadiazine and zinc oxide creams on dose distribution during radiotherapy

Introduction

The use of metallic containing creams to prevent and treat radiodermatitis is controversial and lacking evidence base. We compare the dose effect of two metallic-based skin creams, which could be used for treating radiodermatitis, to a control.

Methodology

Universal containers of silver sulfadiazine cream, zinc oxide cream and aqueous cream were examined using a computed tomography scanner to assess their electron densities relative to water. Second, each cream was exposed to 100 kV and 6 MV photons. The relative doses were measured using an X-ray chamber.

Results

The relative electron density measured was similar for the silver sulfadiazine and aqueous creams. Zinc oxide was 40% higher. The relative dose measurements showed that silver sulfadiazine behaved in a similar way to aqueous cream; however, zinc oxide cream exhibited a dose difference of 11·0% in kV photons and −4·1% in MV photons.

Conclusion

Application of silver sulfadiazine appears unlikely to bring about significant changes in the dose distribution when compared with aqueous during MV or kV radiotherapy. While zinc oxide cream brought about more significant dose changes.

Evaluating the effects of aluminum-containing and non-aluminum containing deodorants on axillary skin toxicity during radiation therapy for breast cancer: a 3-armed randomized controlled trial

PURPOSE

Deodorant use during radiation therapy for breast cancer has been controversial as there are concerns deodorant use may exacerbate axillary skin toxicity. The present study prospectively determined the use of both aluminum-containing and non aluminum containing deodorants on axillary skin toxicity during conventionally fractionated postoperative radiation therapy for breast cancer.

METHODS AND MATERIALS

This 3-arm randomized controlled study was conducted at a single center, tertiary cancer hospital between March 2011 and April 2013. Participants were randomized to 1 of 2 experimental groups (aluminum-containing deodorant and soap or non-aluminum containing deodorant and soap) or a control group (soap). A total of 333 participants were randomized. Generalized estimating equations were used to estimate and compare the odds of experiencing high levels of sweating and skin toxicity in each of the deodorant groups to the odds in the control group. The study evaluated a range of endpoints including objective measurements of axilla sweating, skin toxicity, pain, itch and burning. Quality of life was assessed with a validated questionnaire.

RESULTS

Radiation characteristics were similar across all groups. Patients in the deodorant groups did not report significantly different ratings for axillary pain, itch, or burning compared with the control group. Patients in the aluminum-containing deodorant group experienced significantly less sweating than the control; the odds of their sweating being barely tolerable and frequently or always interfering with their daily activities was decreased by 85% (odds ratio, 0.15; 95% confidence interval, 0.03-0.91).

CONCLUSIONS

We found no evidence that the use of either aluminum-containing or non-aluminum containing deodorant adversely effects axillary skin reaction during conventionally fractionated radiation therapy for breast cancer. Our analysis also suggests patients in the aluminum-containing deodorant arm had significantly less sweating without increased symptoms of axillary radiation skin toxicity. These results add to the evidence that the prescription of deodorants during radiation therapy for breast cancer is now questionable.

Evaluating the relevance of dosimetric considerations to patient instructions regarding skin care during radiation therapy

Introduction

Patient teaching in radiation therapy may include restrictions on applying skin products owing to concerns that the presence of such materials may increase skin dose. These restrictions may create unnecessarily complicated and conflicting self-care instructions.

Purpose

To determine what thickness of skin product is necessary to produce a clinically meaningful dose increase to the skin, and provide recommendations for evidence-based patient instructions.

Methods

Dosimetric measurements and Monte Carlo simulations were used to calculate skin dose under 0–1·5 mm thicknesses of two common classes of skin product for a variety of treatment geometries. The thickness of product required to produce a clinically significant dose increase to the skin was determined.

Results

The thickness of product required to create a clinically meaningful dose increase was >0·7 mm for 10 × 10 cm2 fields and >1·5 mm for 1 × 1 cm2 fields. A typical application of product would be only 0·3 mm.

Conclusion

It seems unrealistic to anticipate patients using sufficiently large quantities of skin product to be of clinical concern. We therefore recommend that there are no dosimetric reasons to restrict the use of these types of skin products during radiation therapy for common treatment scenarios.

Re-examining the evidence in radiation dermatitis management literature: an overview and a critical appraisal of systematic reviews

PURPOSE

To provide an overview and a critical appraisal of systematic reviews (SRs) of published interventions for the prevention/management of radiation dermatitis.

METHODS AND MATERIALS

We searched Medline, CINAHL, Embase, and the Cochrane Library. We also manually searched through individual reference lists of potentially eligible articles and a number of key journals in the topic area. Two authors screened all potential articles and included eligible SRs. Two authors critically appraised and extracted key findings from the included reviews using AMSTAR (the measurement tool for "assessment of multiple systematic reviews").

RESULTS

Of 1837 potential titles, 6 SRs were included. A number of interventions have been reported to be potentially beneficial for managing radiation dermatitis. Interventions evaluated in these reviews included skin care advice, steroidal/nonsteroidal topical agents, systemic therapies, modes of radiation delivery, and dressings. However, all the included SRs reported that there is insufficient evidence supporting any single effective intervention. The methodological quality of the included studies varied, and methodological shortfalls in these reviews might create biases to the overall results or recommendations for clinical practice.

CONCLUSIONS

An up-to-date high-quality SR in the prevention/management of radiation dermatitis is needed to guide practice and direction for future research. We recommend that clinicians or guideline developers critically evaluate the information of SRs in their decision making.

Evidence-based skin care management in radiation therapy: clinical update

OBJECTIVES

To present a clinical update on the available evidence for the prevention and management of radiation skin reactions (radiodermatitis).

DATA SOURCES

Research studies, review articles, and clinical practice guidelines.

CONCLUSION

In the past 4 years since the publication of the original article, there has been minimal change in the evidence available to guide decisions and practice in the management of radiation skin reactions. There continues to be insufficient evidence in the literature to recommend a variety of topical or oral agents in the prevention of skin reactions. There have been some recent studies that have impacted decision making and recommendations in the management of skin reactions. Radiation treatment techniques are the most promising intervention in reducing the degree of skin reaction. The use of calendula cream may reduce the incidence of grade 2 or 3 reactions in women with breast cancer. The controversy related to the use of deodorant in the treatment field unfortunately continues in clinical settings, but deodorant use as part of routine hygiene is now recommended for practice.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses need to be aware of the evidence and lack of evidence when recommending interventions to their patients and avoid undue marketing influence when suggesting interventions for the management of skin reactions. Further research is required to evaluate specific interventions in both the prevention and management of radiation dermatitis.

Management of erythema and skin preservation; advice for patients receiving radical radiotherapy to the breast: a systematic literature review

Objective: To systematically review and critically appraise all evidence on skin care advice and products tailored for patients receiving radical radiotherapy for breast cancer and to determine an evidence-based conclusion regarding the most effective products.

Data Resources and Review Methods: Major healthcare databases were searched with additional efforts made to hand-search current journals. All relevant literature fulfilling the inclusion and exclusion criteria was subjected to quality assurance checks. Those that passed underwent a more rigorous appraisal and were included in the review.

Results: Ten studies were identified as fulfilling the review criteria with regards to aims and quality. All were randomised controlled trials; three were double-blinded, three were single-blinded, the remaining were not blinded. Two addressed washing regimes, two addressed deodorant use, whilst the six remaining studies investigated creams, gels or dressings.

Conclusions: The results suggest that there is a place for creams in the management and delay of radiation-induced skin toxicities; however, research fails to highlight one product which has a demonstrable benefit over others whilst still being cost effective and free from adverse effects. Patients should not be discouraged from washing with water or mild soaps and results suggest that the restriction of aluminium-free deodorant during treatment is unnecessary; however, more research in this area is needed with larger sample sizes.

Acute Skin Toxicity in Breast Cancer Patients Receiving Post-operative Radiotherapy

Post-operative radiotherapy to the breast is a standard treatment for the management of breast cancer. Treatment-related skin toxicity will occur in many patients and usually develops two to three weeks into treatment and may persist for up to four weeks post therapy. Management of acute toxicity remains a challenge for oncology professionals because there is very limited evidence-based research that addresses interventions for the prevention and management of radiation skin damage. Forty breast cancer patients being treated with radiotherapy at Al Amal Hospital were evaluated for the frequency and the severity of acute skin reactions. Clinical skin evaluation was performed by the same Radiation Oncologist during weekly reviews and on the last day of treatment. Normal tissue damage was scored according to the Radiation Therapy Oncology Group side-effect scales. The most frequent acute complications were erythema and dry desquamation, although moist desquamation was a problem in high friction anatomical sites. The reactions were classified as severe (RTOG’2) in only one case. There was remarkable consistency in the assessment and documentation of patient education among nurses following the hospital's standard practice.

An investigation into the use of a non-metallic deodorant during radiotherapy treatment: a randomised controlled trial

Introduction: Many patients in the United Kingdom having radiotherapy for breast cancer are recommended not to use a deodorant during treatment. The advice is not evidence based, it is solely thought as deodorants contained metals, which would react with radiation and cause an increased skin reaction. Hence this research was undertaken to establish whether patients having a course of radiotherapy for breast cancer could use a deodorant as part of their daily routine.

Method: The research took place between May 2004 and February 2005. A total of 192 breast cancer patients were recruited. This included breast or chest-wall patients with or without axilla involvement. The study was designed with two groups. Group 1 used no deodorant and Group 2 a specific deodorant. The researcher reviewed patients weekly, assessing skin reactions and recording the researcher and patient's observations.

Results: Most patients experienced no reaction or mild erythema and dry desquamation in the axilla. This was observed in both groups. Therefore, findings of this study indicate that future breast cancer patients should be given the choice of using this deodorant.

Further recommendations: Test the reliability of the skin assessment form, extend the research to include other patient groups who have their axilla treated, test different deodorants.

Evidence-based skin care management in radiation therapy

OBJECTIVES

To review published studies evaluating interventions for the prevention and management of radiation skin reactions/dermatitis.

DATA SOURCES

Research studies, review articles, and clinical practice guidelines.

CONCLUSION

There is insufficient evidence in the literature to recommend specific topical or oral agents in the prevention or management of skin reactions. Recent limited evidence suggests that the use of calendula cream may reduce the incidence of grade 2 and 3 reactions in women with breast cancer. Additionally, early studies evaluating the use of barrier films or creams may improve moist desquamation.

IMPLICATIONS FOR NURSING PRACTICE

Oncology nurses need to increase their awareness of the evidence or lack of evidence when recommending interventions to their patients. Further research is required to evaluate interventions in the prevention and management of radiation dermatitis.

The validity of skin care protocols followed by women with breast cancer receiving external radiation

Skin care in women receiving external radiation to the breast varies among institutions. Studies have been conducted looking at the effect that various skin care products have on the onset and severity of radiation-induced skin reactions in those patients. Results show that no significant difference exists among these products. The practice of avoiding aluminum-based deodorant on the treated side and avoiding use of any skin care products four hours prior to treatment is not evidence based but often is part of skin care protocols for women receiving breast irradiation. A review of the literature since 1996 in the United States, Canada, United Kingdom, and Australia revealed some evidence to refute the practice but no supporting evidence. Because minimal disruption in a woman's normal hygiene routine could mitigate anxiety and improve coping during a time of extreme stress brought on by a cancer diagnosis, further research is warranted to support changing the practice.

The prevention and management of acute skin reactions related to radiation therapy: a systematic review and practice guideline

GOALS OF WORK

To develop a practice guideline report on the questions: What are the optimal methods to prevent acute skin reactions (occurring within the first 6 months of irradiation) related to radiation therapy? What are the optimal methods to manage acute skin reactions related to radiation therapy?

MATERIALS AND METHODS

Cancer Care Ontario's Supportive Care Guidelines Group (SCGG) conducted a systematic review of literature on this topic. Evidence-based recommendations were formulated to guide clinical decision making, and a formal external review process was conducted to validate the relevance of these opinions for Ontario practitioners.

MAIN RESULTS

Twenty-eight trials meeting the inclusion criteria were identified. Of the twenty-three trials that evaluated preventative methods, washing was the only practice which significantly prevented skin reaction. Some evidence suggested topical steroid creams and calendula ointment might be effective. None of the five trials evaluating skin reaction management detected a positive effect using steroid cream, sucralfate cream, or dressings.

CONCLUSIONS

Skin washing, including gentle washing with water alone with or without mild soap, should be permitted in patients receiving radiation therapy to prevent acute skin reaction. There is insufficient evidence to support or refute specific topical or oral agents for the prevention or management of acute skin reaction. In the expert opinion from the SCGG, the use of a plain, non-scented, lanolin-free hydrophilic cream may be helpful in preventing radiation skin reactions. In addition, a low dose (i.e., 1%) corticosteroid cream may be beneficial in the reduction of itching and irritation.

Accurate skin dose measurements using radiochromic film in clinical applications

Megavoltage x-ray beams exhibit the well-known phenomena of dose buildup within the first few millimeters of the incident phantom surface, or the skin. Results of the surface dose measurements, however, depend vastly on the measurement technique employed. Our goal in this study was to determine a correction procedure in order to obtain an accurate skin dose estimate at the clinically relevant depth based on radiochromic film measurements. To illustrate this correction, we have used as a reference point a depth of 70 micron. We used the new GAFCHROMIC dosimetry films (HS, XR-T, and EBT) that have effective points of measurement at depths slightly larger than 70 micron. In addition to films, we also used an Attix parallel-plate chamber and a home-built extrapolation chamber to cover tissue-equivalent depths in the range from 4 micron to 1 mm of water-equivalent depth. Our measurements suggest that within the first millimeter of the skin region, the PDD for a 6 MV photon beam and field size of 10 x 10 cm2 increases from 14% to 43%. For the three GAFCHROMIC dosimetry film models, the 6 MV beam entrance skin dose measurement corrections due to their effective point of measurement are as follows: 15% for the EBT, 15% for the HS, and 16% for the XR-T model GAFCHROMIC films. The correction factors for the exit skin dose due to the build-down region are negligible. There is a small field size dependence for the entrance skin dose correction factor when using the EBT GAFCHROMIC film model. Finally, a procedure that uses EBT model GAFCHROMIC film for an accurate measurement of the skin dose in a parallel-opposed pair 6 MV photon beam arrangement is described.

Management of skin reactions during radiotherapy: a study of nursing practice

The aim of this study was to investigate the consensus of skin care advice given by nurses during radiotherapy. Sixty-seven nurses, identified through nine Belgian radiotherapy departments, responded to a questionnaire survey consisting of 58 items regarding prevention and management of erythema, dry desquamation and moist desquamation. Consensus for a given advice was categorized as small if less than 50% of the nurses gave the same answer, as moderate if between 50% and 75% and as large when more than 75%. Overall, 33% of the items showed small consensus, 29% showed moderate consensus and 38% showed large consensus. The highest consensus was seen for advice in cases of moist and dry desquamation. There was less agreement in the case of erythema and it decreased further for preventive advice. Some skin care techniques that were frequently used by the nurses cannot be supported by the literature. Also, some techniques recommended by the literature are not frequently used. Further, few differences (P < 0.05) between nurses working in a university hospital and the ones working in a non-university hospital were found in terms of advice given to patients. To increase consensus on skin care issues more conclusive research is needed. Of equal importance is the translation of existing research results into daily clinical practice.