Sequential pulmonary effects of radiotherapy detected by functional and radiological end points in women with breast cancer

Developing of predictive models for pneumonitis with forward variable selection and LASSO logistic model for breast cancer patients treated with 3D-CRT

Purpose: To develop a multiple logistic regression model as normal tissue complication probability model by least absolute shrinkage and selection operator (LASSO) technique in breast cancer patients treated with three-dimensional conformal radiation therapy (3D-CRT), we focused on the changes of pulmonary function tests to achieve the optimal predictive parameters for the occurrence of symptomatic radiation pneumonitis (SRP).

Materials and methods: Dosimetric and spirometry data of 60 breast cancer patients were analyzed. Pulmonary function tests were done before RT, after completion of RT, 3, and 6 months after RT. Multiple logistic regression model was used to obtain the effective predictive parameters. Forward selection method was applied in NTCP model to determine the effective risk factors from obtained different parameters.

Results: Symptomatic radiation pneumonitis was observed in five patients. Significant changes in pulmonary parameters have been observed at six months after RT. The parameters of mean lung dose (MLD), bridge separation (BS), mean irradiated lung volume (ILVmean), and the percentage of the ipsilateral lung volume that received dose of 20 Gy (IV20) introduced as risk factors using the LASSO technique for SRP in a multiple normal tissue complication probability model in breast cancer patients treated with 3D-CRT. The BS, central lung distance (CLD) and ILV in tangential field have obtained as 23.5 (20.9-26.0) cm, 2.4 (1.5-3.3) cm, and 12.4 (10.6-14.3) % of lung volume in radiation field in patients without pulmonary complication, respectively.

Conclusion: The results showed that if BS, CLD, and ILV are more than 23 cm, 2 cm, and 12%, respectively, so incidence of SRP in the patients will be considerable. Our multiple NTCP LASSO model for breast cancer patients treated with 3D-CRT showed that in order to have minimum probability of SRP occurrence, parameters of BS, IV20, ILV and especially MLD would be kept in minimum levels. Considering dose-volume histogram, the mean lung dose factor is most important parameter which minimizing it in treatment planning, minimizes the probability of SRP and consequently improves the quality of life in breast cancer patients.

Occurrence of pneumonitis following radiotherapy of breast cancer - A prospective study

AIM

of this study is to determine the temporal resolution of therapy-induced pneumonitis, and to assess promoting factors in adjuvant treated patients with unilateral mammacarcinoma.

PATIENTS AND METHODS

A total of 100 post-surgery patients were recruited. The cohort was treated by 2 field radiotherapy (2FRT; breast and chest wall, N = 75), 3 field radiotherapy (3FRT; + supraclavicular lymphatic region, N = 8), or with 4 field radiotherapy (4FRT; + parasternal lymphatic region, N = 17). Ninety-one patients received various systemic treatments prior to irradiation. Following an initial screening visit post-RT, two additional visits after 12 and 25 weeks were conducted including radiographic examination. In addition, general anamnesis and the co-medication were recorded. The endpoint was reached as soon as a pneumonitis was developed or at maximum of six months post-treatment.

RESULTS

A pneumonitis incidence of 13% was determined. Of 91 patients with prior systemic therapy, 11 patients developed pneumonitis. Smoking history and chronic obstructive pulmonary disease (COPD) appeared to be positive predictors, whereas past pneumonia clearly promoted pneumonitis. Further pneumonitis-promoting predictors are represented by the applied field extensions (2 field radiotherapy [2FRT] < 3 field radiotherapy [3FRT] < 4 field radiotherapy [4FRT]) and the type of combined initial systemic therapies. As a consequence, all of the three patients in the study cohort treated with 4FRT and initial chemotherapy combined with anti-hormone and antibody protocols developed pneumonitis. A combination of the hormone antagonists tamoxifen and goserelin might enhance the risk for pneumonitis. Remarkably, none of the 11 patients co-medicated with statins suffered from pneumonitis.

CONCLUSIONS

The rapidly increasing use of novel systemic therapy schedules combined with radiotherapy (RT) needs more prospective studies with larger cohorts. Our results indicate that contribution to pneumonitis occurrence of various (neo)adjuvant therapy approaches followed by RT is of minor relevance, whereas mean total lung doses of >10 Gy escalate the risk of lung tissue complications. The validity of potential inhibitors of therapy-induced pneumonitis as observed for statin co-medication should further be investigated in future trials.

Radiation Pneumonitis After Conventional Radiotherapy For Breast Cancer: A Prospective Study

BACKGROUND

Loco-regional radiotherapy is an important treatment modality in breast cancer and radiation pneumonitis (RP) is one of the early toxicities.

AIM

To study the occurrence, correlation of RP with patient and radiotherapy related factors and the effects on pulmonary function following conventional radiotherapy in breast cancer.

SETTINGS AND DESIGN

Prospective study, from a tertiary hospital in a developing country.

MATERIALS AND METHODS

Prospective analysis of clinical symptoms, pulmonary function and radiologic changes was done prior to and 12 weeks after adjuvant radiotherapy (n=46). Statistical analysis was done using SPSS version 10 software.

RESULTS

Radiological and clinical RP was seen in 45.65% (n=21) and 19.56% (n=9) respectively. RP was significantly higher with age >50 years (OR 4.4), chest wall irradiation with electrons, (electrons 83.3% vs cobalt60 32.4%, p=0.02) and supraclavicular field treatment with 6 MV photons (p= 0.011). There was significant relationship between Inferior Lung Distance (ILD) and RP (p=0.013). The fall in Total Lung Capacity (TLC) was significantly more in those with RP (p=0.02).

CONCLUSION

Clinical RP occurs in almost one-fifth of breast cancer patients treated with conventional radiotherapy. Chest wall irradiation with electrons, supraclavicular field irradiation with 6 MV photons, higher ILD and age >50 years was associated with increased RP. The pulmonary function parameter most affected was TLC. The factors associated with increased RP should be considered when adjuvant radiotherapy is planned to minimize its likelihood and intervene appropriately.

Efeito da radioterapia na função pulmonar e na fadiga de mulheres em tratamento para o câncer de mama

O presente estudo comparou a função pulmonar e a fadiga de mulheres antes e após a radioterapia (RT) adjuvante para tratamento do câncer de mama, e correlacionou a função pulmonar com a dose de radiação e fadiga. Foi conduzido um estudo observacional longitudinal envolvendo 20 mulheres. A função pulmonar foi avaliada pela espirometria (ClementClarke®) e manovacuometria (GlobalMed®, modelo MVD 300), e a fadiga pelo Functional Assessment of Cancer Therapy Fatigue (FACT-F). Todas as avaliações foram realizadas antes da primeira sessão e uma semana após o término da RT adjuvante. Para a análise estatística foram utilizados os testes Wilcoxon Signed Rank Test e correlação de Spearman, adotando-se nível de significância p<0,05. Na espirometria, encontrou-se redução significativa da capacidade vital forçada (23,52%), do volume expiratório forçado no primeiro segundo (26,23%) e do pico de fluxo expiratório (10,12%) (p=0,001). As pressões expiratórias e inspiratórias máximas também diminuíram significativamente (25,45 e 32,92%, respectivamente). Observou-se diminuição significativa do bem-estar físico e do bem-estar funcional, e um aumento significativo da fadiga no FACT-F (p=0,001). Não foram observadas correlações entre as variáveis da função pulmonar com a dose de radiação e fadiga. Em curto prazo, a RT promoveu redução na função pulmonar, mas a mesma permaneceu próxima à normalidade para a amostra estudada. Observou-se aumento significativo da fadiga e diminuição dos escores dos domínios bem-estar físico e funcional.

Imaging radiation-induced normal tissue injury

Technological developments in radiation therapy and other cancer therapies have led to a progressive increase in five-year survival rates over the last few decades. Although acute effects have been largely minimized by both technical advances and medical interventions, late effects remain a concern. Indeed, the need to identify those individuals who will develop radiation-induced late effects, and to develop interventions to prevent or ameliorate these late effects is a critical area of radiobiology research. In the last two decades, preclinical studies have clearly established that late radiation injury can be prevented/ameliorated by pharmacological therapies aimed at modulating the cascade of events leading to the clinical expression of radiation-induced late effects. These insights have been accompanied by significant technological advances in imaging that are moving radiation oncology and normal tissue radiobiology from disciplines driven by anatomy and macrostructure to ones in which important quantitative functional, microstructural, and metabolic data can be noninvasively and serially determined. In the current article, we review use of positron emission tomography (PET), single photon emission tomography (SPECT), magnetic resonance (MR) imaging and MR spectroscopy to generate pathophysiological and functional data in the central nervous system, lung, and heart that offer the promise of, (1) identifying individuals who are at risk of developing radiation-induced late effects, and (2) monitoring the efficacy of interventions to prevent/ameliorate them.

Cardiorespiratory fitness and quality-of-life analysis posttreatment in breast cancer survivors

This study compared VO(2peak), treatment frequency and dosage, and QOL between 22 post-treated breast cancer survivors (CATotal) and 22 apparently healthy, age-matched women (CO). The CATotal group included 11 with no history of any other co-morbidities (CA) and 11 with controlled hypertension (CA + H). VO(2peak) was measured using the Bruce Protocol. QOL was measured using the SF-36 survey. Significant differences were observed in VO(2peak) between CATotal and CO (p = 0.014), CA and CA + H (p = 0.001), and CA + H and CO (p = 0.001). Physical, emotional, and mental health domains of the SF-36 were significantly different between CATotal and CO (p = 0.006, 0.001, and 0.05 respectively). These results suggest that breast cancer survivors with controlled hypertension can experience a significant reduction in VO(2peak) when compared to apparently healthy, age-matched controls. Also, treatment frequency and dosage affected QOL in this group of survivors.

Função pulmonar em mulheres com câncer de mama submetidas à radioterapia: um estudo piloto

O câncer de mama é a forma de câncer que mais causa mortes entre mulheres no Brasil. O tratamento consiste em intervenção cirúrgica, quimioterapia, hormonioterapia e radioterapia, esta última responsável por uma significativa diminuição na taxa de recorrência local do câncer, mas que pode afetar a função pulmonar. O objetivo deste estudo foi detectar alterações pulmonares funcionais decorrentes da radioterapia no tratamento do câncer de mama. Participaram do estudo 10 mulheres submetidas a tratamento do câncer de mama, avaliadas quanto à função pulmonar antes e após a radioterapia. Foram mensuradas capacidade inspiratória e capacidade vital forçada, por espirômetro de incentivo, e pressões inspiratória e expiratória máximas, por manovacuômetro. Embora tenha havido redução, em vários casos, dos valores medidos antes e depois da radioterapia, não foi encontrada diferença estatisticamente significativa. Nas pacientes avaliadas, pois, a radioterapia não parece ter prejudicado a função pulmonar.

The intersection of cancer and aging: establishing the need for breast cancer rehabilitation

The increasing success of treatments for common cancers has resulted in growing awareness of the unique health care needs of cancer survivors. Cancer treatments can be toxic and have long-lasting effects on health, potentially accelerating the aging process and producing associated declines in physical function. In this synthesis of the literature, we critically examine the strength of existing evidence that breast cancer diagnosis and treatment are associated with a disproportionate decline in physical function compared with the effects of living without cancer for the same number of years. There is some observational epidemiologic evidence that women treated for breast cancer report greater declines in physical function than their peers. Discerning the factors associated with such declines and their clinical significance remains to be addressed. Physiologic, psychological, and behavioral changes associated with both aging and cancer treatment are reviewed. Parallels are proposed between existing preventive and rehabilitative programs and possibilities for similar interventions aimed at preventing, reversing, or halting declines in physical function in cancer survivors. Finally, a program of research is proposed to evaluate whether there is some subset of breast cancer survivors for whom prevention or rehabilitation of functional status declines is needed, as well as development of targeted, mechanistically driven interventions.

Morbidity after breast cancer treatment and physiotherapeutic performance

Breast cancer (BC) accounts for >30% of all new cancer patients among women but with increased early detection rates and improved adjuvant therapy, the 5-year survival rate presently reaches >85%. As the number of BC survivors increases, research into the sequelae of the cancer and its treatment on quality of life is a priority. Understanding the potential complications of treatment and developing effective rehabilitation techniques can reduce the impact of such effects on activities of daily life. The aim of this review is to discuss the major sequelae of treatment for BC, and the physiotherapist's role in the prevention and treatment of such complications. Breast cancer treatment can result in pulmonary and upper extremity morbidities that may manifest either early or late. Prevention and treatment of lymphoedema, scar adherence and pulmonary complications can be achieved. Additionally pain reduction and maintenance of range of movement, muscle strength and adequate posture are parts of physiotherapy, which is an important component in the rehabilitation of women with BC.

The Role of Functional Imaging in the Diagnosis and Management of Late Normal Tissue Injury

Normal tissue injury after radiation therapy (RT) can be defined based on either clinical symptoms or laboratory/radiologic tests. In the research setting, functional imaging (eg, single-photon emission computed tomography [SPECT], positron-emission tomography [PET], and magnetic resonance imaging [MRI]) is useful because it provides objective quantitative data such as metabolic activity, perfusion, and soft-tissue contrast within tissues and organs. For RT-induced lung, heart, and parotid gland injury, pre- and post-RT SPECT images can be compared with the dose- and volume-dependent nature of regional injury. In the brain, SPECT can detect changes in perfusion and blood flow post-RT, and PET can detect metabolic changes, particularly to regions of the brain that have received doses above 40 to 50 Gy. On MRI, changes in contrast-enhanced images, T(1) and T(2) relaxation times, and pulmonary vascular resistance at different intervals pre- and post-RT show its ability to detect and distinguish different phases of radiation pneumonitis. Similarly, conventional and diffusion-weighted MRI can be used to differentiate between normal tissue edema, necrosis, and tumor in the irradiated brain, and magnetic resonance spectroscopy can measure changes in compounds, indicative of membrane and neuron disruption. The use of functional imaging is a powerful tool for early detection of RT-induced normal tissue injury, which may be related to long-term clinically significant injury.

Physiological imaging of the lung: single-photon-emission computed tomography (SPECT)

Emission tomography provides three-dimensional, quantitative images of the distribution of radiotracers used to mark physiological, metabolic, or pathological processes. Quantitative single photon emission computed tomography (SPECT) requires correction for the image-degrading effects due to photon attenuation and scatter. Phantom experiments have shown that radioactive concentrations can be assessed within some percentage of the true value when relevant corrections are applied. SPECT is widely spread, and radiotracers are available that are easy to use and comparably inexpensive. Compared with other methods, SPECT suffers from a lower spatial resolution, and the time required for image acquisition is longer than for some alternative methods. In contrast to some other methods, SPECT allows simultaneous imaging of more than one process, e.g., both regional blood flow and ventilation, for the whole lung. SPECT has been used to explore the influence of posture and clinical interventions on the spatial distribution of lung blood flow and ventilation. Lung blood flow is typically imaged using macroaggregates of albumin. Both radioactive gases and particulate aerosols labeled with radioactivity have been used for imaging of regional ventilation. However, all radiotracers are not equally suited for quantitative measurements; all have specific advantages and limitations. With SPECT, both blood flow and ventilation can be marked with radiotracers that remain fixed in the lung tissue, which allows tracer administration during conditions different from those at image registration. All SPECT methods have specific features that result from the used radiotracer, the manner in which it is administered, and how images are registered and analyzed.