Complications of combined radiotherapy and chemotherapy

Prevalence and susceptibility profile of Candida spp. isolated from patients in cancer therapy

OBJECTIVE

This study determined the prevalence of Candida spp. in the saliva of cancer patients. Furthermore, we assessed the antimicrobial activity of mouthwashes against the isolated strains and its susceptibility to amphotericin B and fluconazole.

METHODS

Thirty-four cancer patients undergoing radiotherapy, chemotherapy alone or combined treatment were investigated for oral Candida spp. colonization and compared in regard to mucositis presence. The maximum inhibitory dilution was used to assess the antimicrobial activity of Periogard®, Cepacol® Cool Ice and 0.12 % Chlorhexidine Digluconate mouthwashes against the isolates. In parallel, susceptibility to amphotericin B and fluconazole was determined by agar-based E-test. Data did not adhere to normal distribution as inferred by the Shapiro-Wilk test and statistical analysis was conducted by non-parametric McNemar test (α0.05).

RESULTS

Twenty-seven participants (79.4 %) were male, 19 (55.9 %) had mucositis and 9 (26.5 %) were colonized by Candida spp. 12 different strains of Candida spp. were isolated, being Candida albicans the most prevalent strain. Risk of Candida spp. colonization was increased by almost twofold among the participants with mucositis (odds ratio: 1.84; 95 % confidence interval: 0.37-9.07). Mouthwash Cepacol® Cool Ice presented better antimicrobial activity against Candida spp. while 0.12 % Chlorhexidine exhibited the worst activity. All strains were sensitive to amphotericin B, and 2 non-albicans strains were dose-dependent sensitive to fluconazole.

CONCLUSION

Considering the increased risk of colonization byCandida spp. in patients with mucositis, and the emergence of antifungal drug resistance, the antiseptics use could benefit the maintenance of cancer patient's oral health.

An integrative review of skin assessment tools used to evaluate skin injury related to external beam radiation therapy

AIMS AND OBJECTIVES

To review literature associated with external beam radiotherapy and skin damage. A focus of the literature search is to highlight and discuss the myriad of skin assessment tools that are available to the clinician when assessing skin injury in patients receiving external beam radiation therapy.

BACKGROUND

It is apparent that despite considerable work being progressed in the development of individualised skin assessment tools, uptake and use is poor. These tools are designed to assist the clinician in the evaluation of damaged skin and predict the radiation wound development pathway.

DESIGN

An integrated review can be used to address a mature or new and emerging topic through a systematic methodology, which is either theoretical or empirical, gained from research, practice or policy initiatives (Whittemore & Knafl, Journal of Advanced Nursing, 52, 2005, 546). This review is particularly concerned with the employment of skin assessment tools by clinicians in patients with radiation damaged skin. Using the search terms synonyms for radiation, skin and epidermal damage, PubMed/MEDLINE, Medical Complete and Web of Science databases were searched. Consulting professional peers was employed as part of the inclusion and exclusion process.

CONCLUSION

There is a high level of unpredictability about which patient will have an uncomplicated course of external beam radiotherapy. Variables may include, but are not limited to, an acute reaction, a delayed reaction resulting in actual skin damage or no visible skin disturbance. The skin assessment tools that are readily available are not regularly referenced in clinical practice when attempting to manage the many side effects of radiation therapy. Skin assessment tools require ongoing clinical validation, so they can be used to guide practitioners to undertake further assessment of skin integrity.

RELEVANCE TO CLINICAL PRACTICE

The current body of knowledge suggests clinicians caring for patients receiving therapeutic radiotherapy should consider integrating a recognised patient assessment skin framework into their daily routine. Such validated tools may add value to postradiotherapy patient care by providing a consistency of management and accordingly refining best practice.

[Reversibility of radiation-induced fibroatrophy]

PURPOSE

The radiation-induced fibro-atrophic process described in numerous tissues and organs is a localized and irreversible late effect of high-dose radiation therapy. Our purpose is to show that this process is today reversible.

CURRENT KNOWLEDGE AND KEY POINTS

This review describes a synthesis of various clinical, paraclinical and histopathological aspects of radiation-induced fibro-atrophic process, and of cellular and molecular process regulation. Schematically, there exists a prefibrotic aspecific inflammatory phase, then a constituted and cellular phase, then a matricial densification and remodeling phase, associated in some cases with a tissular terminal necrosis. The respective parts and their evolution during time of the main protagonists as myofibroblast, extracellular matrix and growth factor TGF beta 1 are clarified. From the pathophysiological mechanisms described, curative therapeutic attitudes are proposed for the different progressive phases. Especially, superoxide dismutase (not available) and the pentoxifylline-tocopherol combination seem to allow reduction and reversibility of the fibro-atrophic radiation-induced established process, in clinics as in animal experiments.

FUTURE PROSPECTS AND PROJECTS

Some phase II trials try to assess the therapeutic interest of combined pentoxifylline-tocopherol in various radiation-induced sequelae, as in osteo-radionecrosis. A clinical randomized trial phase III has just been achieved and could support the results of these experimental and retrospective clinical trials.

Morbidity related to axillary irradiation in the treatment of breast cancer

Some of the most debilitating morbidity after surgery and radiotherapy for breast cancer is related to treatment of the axilla. This includes persistent arm lymphoedema, impaired shoulder mobility and brachial plexopathy. Considerable research efforts have been carried out on the radiation pathogenesis and the clinical radiobiology of these clinical endpoints, which has enabled their severity and incidence to be minimized. It is clear that the radiation dose-response relationships for these late endpoints are very steep. In other words, even small changes in the exact dose fractionation and physical dose distribution can cause major changes in toxicity. In particular, in many treatment schedules dose fractions larger than 2 Gy have been used without a sufficient reduction in total dose to avoid increased late effects. This is important, as much of the available literature reports side effects after suboptimal dose-fractionation schedules and inferior radiotherapy techniques. Such reports are not representative of what can be achieved using modern radiotherapy. An interesting parallelism to the problems encountered in reviewing historical experience is found in the British breast litigation, the current status of which is presented in this article. Furthermore, morbidity after radiotherapy is strongly influenced by concomitant surgery and/or chemotherapy, and this should be allowed for when designing the overall treatment. Apart from other therapeutic modalities, it has been suggested that other exogenous factors have an influence on the risk of radiotherapy-related morbidity. However, patients' age and, in the case of lymphoedema, also obesity are the only factors that have been established with some certainty. Routine adjustment of radiotherapy dose in these cases is not recommended. Two current developments may strengthen the role of radiotherapy in the treatment of breast cancer. Sentinel node biopsy may allow nodal staging without major surgical excision of axillary nodes and this opens the possibility for a more optimal combination of radiotherapy and surgery in the management of the axilla. With more cancers now being detected by systematic screening programmes, this will also increase the possibilities for conservative management, which in most cases involves radiotherapy. In conclusion, the improved understanding of the clinical radiobiology of late sequelae after radiotherapy allows treatment schedules and techniques to be devised that are therapeutically effective while maintaining a minimal risk of serious, late morbidity.

Radiotherapy in bladder cancer

In the present review, we have evaluated the outcome of radiotherapy in patients with bladder cancer. The exact value of radical radiotherapy is difficult to establish because changes in treatment techniques and selection of patients have biased the results. The 5-year survival rates are reported to be 35-71% in T1 tumors, 27-59% in T2 tumors, 10-38% in T3 tumors and 0-16% in T4 tumors. Several other factors, like performance status and hemoglobin level, are important for the outcome. Morbidity of radical radiotherapy depends on several treatment and patient related factors, but 50-75% experience acute intestinal or urological symptoms and 10-20% may develop severe late toxicity, depending on the kind of registration. The importance of field size or overall treatment time cannot be established from available data. Hyperfractionation with dose escalation has proven effective in one study. Preoperative radiotherapy with cystectomy has not proven better than cystectomy alone or better than radiotherapy alone. The addition of systemic chemotherapy has increased disease-free survival, but has not significantly reduced the rate of distant metastases or improved overall survival. Presently, the standard radiation regimen is a conventional dose and fractionation schedule to a total dose of 60-66 Gy with a three- or four-field technique covering the bladder and tumor. The efficacy of additional irradiation of regional lymph nodes is questionable. New treatment possibilities with advanced techniques of radiotherapy, hyperfractionation and dose escalation and/or the addition of systemic chemotherapy may improve outcome. These options should be further explored in clinical trials.

[Late effects of mammary radiotherapy on skin and subcutaneous tissues]

Late damages to the skin and subcutaneous tissues are almost inescapable because of the high skin doses required in the irradiation of breast tumours. While the clinical and histological descriptions date back to the first decades of the therapeutic use of ionising radiation, the recent advances in cellular and molecular biology have significantly contributed to the increased understanding of late skin injury mechanisms. In particular, sub-cutaneous fibrosis appears to be the partly reversible results of a continuous and self-maintained local process, possibly sensitive to therapeutic intervention. A second very active research avenue is the development of biologic assays potentially able to predict the probability of increased normal tissue injury after irradiation in individual patients. Such a test would allow the adaptation of the treatment modalities to the radiobiological behaviour of normal tissues. To date, these expectations have not been met. The quality of the irradiation and its modalities (total dose, fractionation, inter fraction interval) remain the main ways to achieve an optimal functional and cosmetic outcome.

[Late effects of ionizing radiations on the bone marrow]

Bone marrow is a tissue with a high mitotic activity, and consequently exquisitely radiosensitive. The clinical effects of bone marrow irradiation and its ability of regeneration are related to the volume irradiated. Management of hematopoietic side effects of radiation include surveillance, antibiotics, blood products transfusion, and more scarcely hematopoietic growth factors, bone marrow transplantation and peripheral blood stem cells reinfusion.