Role of systemic therapy in the development of lung sequelae after conformal radiotherapy in breast cancer patients

Pulmonary fibrosis prevalence after adjuvant radiotherapy of Iranian patients with breast cancer: A single-center cross-sectional study

AIMS

This study aims to investigate the incidence rate of pulmonary fibrosis as a late radiotherapy complication and identify the associated dosimetric and demographic factors using radiological findings between Iranian patients with breast cancer.

METHODS AND MATERIAL

Breast cancer patients treated at the education hospital of Shohada-e Tajrish Hospital, Tehran, Iran, from 2017 to 2021 were considered. Patients have included for whom a secondary chest CT scan was available at least six months after radiotherapy. Dose-volume histogram (DVH) parameters of three-dimensional conformal radiotherapy (3D-CRT) treatment plans were exported. Demographic features and data on underlying lung diseases, diabetes, and smoking history were extracted.

RESULTS

A total of 250 patients were included in the study with a mean age of 46.1 ± 7.5 yrs and a mean body mass index (BMI) of 24.5 ± 4.2 kg/m2. Pulmonary fibrosis was detected for sixty-two cases. A significant relationship was obtained between the ipsilateral lung DVH parameters of patients with pulmonary fibrosis (P value < 0.05). The V5Gy, V10Gy, V13Gy, V20Gy, V30Gy, MLD, and DMax for individuals with pulmonary fibrosis were significantly higher than those without this injury.

CONCLUSIONS

Pulmonary fibrosis was distinguished for 25% of the breast cancer cases at least six months after adjuvant radiotherapy. A significant relationship between the DVH parameters, underlying lung disease, diabetes, radiotherapy fields (i.e., Breast + LN + SC or Breast/Chest-wall only), age, and BMI with the frequency of the ipsilateral pulmonary fibrosis was obtained. V13Gy and V30Gy of the ipsilateral lung may be the most predictor of pulmonary fibrosis incidence.

[Radiotherapy and targeted therapy for the management of breast cancer: A review]

The purpose of this study was to review the current knowledge regarding combinations of the most commonly used targeted therapies or those under development for the management of breast cancer with radiation therapy. Several studies have shown that the combination of radiation therapy and tamoxifen increased the risk of radiation-induced lung toxicity; therefore, the two modalities are generally not given concurrently. The combination of HER2 inhibitors (trastuzumab, pertuzumab) and radiation therapy appeared to be safe. However, trastuzumab emtansine (T-DM1) should not be given concomitantly with brain radiation therapy because this combination may increase the risk of brain radionecrosis. The combination of radiation therapy with other new targeted therapies such as new selective estrogen receptor modulators (SERDs), lapatinib, cell cycle inhibitors, immune checkpoint inhibitors, or molecules acting on DNA damage repair seems feasible but has been mainly evaluated on retrospective or prospective studies with small numbers of patients. Moreover, there is a great heterogeneity between these studies regarding the dose and fractionation used in radiotherapy, the dosage of systemic treatments and the sequence of treatments used. Therefore, the combination of these new molecules with radiotherapy should be proposed sparingly, under close monitoring, pending the ongoing prospective studies cited in this review.

Radiation therapy in the thoracic region: Radio-induced cardiovascular disease, cardiac delineation and sparing, cardiac dose constraints, and cardiac implantable electronic devices

Radiation therapy in the thoracic region may deliver incidental ionizing radiation to the surrounding healthy structures, including the heart. Radio-induced heart toxicity has long been a concern in breast cancer and Hodgkin's lymphoma and was deemed a long-term event. However, recent data highlight the need to limit the dose to the heart in less favorable thoracic cancers too, such as lung and esophageal cancers in which incidental irradiation led to increased mortality. This article will summarize available cardiac dose constraints in various clinical settings and the types of radio-induced cardiovascular diseases encountered as well as delineation of cardiac subheadings and management of cardiac devices. Although still not completely deciphered, heart dose constraints remain intensively investigated and the mean dose to the heart is no longer the only dosimetric parameter to consider since the left anterior descending artery as well as the left ventricle should also be part of dosimetry constraints.

Does shortening the duration of radiotherapy treatment in breast cancer increase the risk of radiation pneumonia: A retrospective study

Randomized studies evaluating hypofractionation and conventional fractionation radiotherapy treatments (RT) in patients with breast cancer have shown that hypofractionation achieves similar results to conventional fractionation in terms of survival and local control rates. It has also been shown that their long-term toxicities are similar. This study aimed to evaluate the effects of hypofractionated radiotherapy (H-RT) and conventional radiotherapy (C-RT) on lung toxicity and identify factors affecting this toxicity in patients with breast cancer. The study included 118 patients who underwent adjuvant RT following breast-conserving surgery (BCS). Out of these, 63 patients were assigned to receive C-RT, while the remaining 55 were assigned to receive H-RT. To clarify, we treated 63 patients with C-RT and 55 patients with H-RT. 60 patients were treated using 3-dimensional conformal radiotherapy (3DCRT) and 58 patients were treated using intensity modulated radiotherapy (IMRT). The patients were evaluated weekly for toxicity during radiotherapy (RT) treatment and were called every 3 months for routine controls after the treatment. The first control was performed 1 month after the treatment. Statistical analysis was performed using the SPSS20 program, and a P value of <.005 was considered statistically significant. The study found that the median age of the participants was 54.9 years and tomographic findings were observed in 70 patients. Radiological findings were detected at a median of 5 months after RT. The mean lung dose (MLD) on the treated breast side (referred to as ipsilateral lung or OAR) was 10.4 Gy for the entire group. Among patients who received 18 MV energy in RT, those with an area volume (V20) of the lung on the treated breast side >18.5%, those with a mean dose of the treated breast side lung (ipsilateral lung) >10.5 Gy, and those who received concurrent hormone therapy had significantly more tomographic findings. However, patients treated with YART had fewer tomographic findings. No symptomatic patients were observed during the follow-up period. Our findings show that the risk of lung toxicity is similar with H-RT and C-RT, and H-RT can be considered an effective and safe treatment option for breast cancer. The key factors affecting the development of lung toxicity were found to be the type of RT energy used, RT to the side breast, volume receiving 20 Gy in the side lung, side lung mean dose, and simultaneous hormonal therapy.

Delayed adjuvant endocrine therapy is associated with decreased recurrence-free survival following neoadjuvant chemotherapy for breast cancer

BACKGROUND

In hormone receptor-positive breast cancer (HRPBC), endocrine therapy is often initiated after adjuvant radiotherapy given concerns of radiation fibrosis. No studies have investigated how this may impact outcomes in high-risk patients undergoing neoadjuvant chemotherapy (NAC).

METHODS

Females with nonmetastatic HRPBC receiving NAC from 2011 to 2017 were identified from our multi-institutional database. Interval from surgery to endocrine therapy (ISET) was calculated in weeks. Recurrence-free survival (RFS) and overall survival (OS) were evaluated with Kaplan-Meier and Cox proportional hazards modeling.

RESULTS

Of 280 patients, 179 (64%) received adjuvant radiotherapy; all deaths (n = 25) and 90% (n = 27) of recurrences occurred in this group, which was the focus of subsequent analysis. Median follow-up was 49 months. Recurrences were predominantly distant metastases (n = 21, 81%). Median ISET was 12 weeks (range 0-55 weeks). On multivariable analysis, ISET >14 weeks was independently associated with worse RFS (HR 3.20, 95% C.I. 1.22-8.40, P = 0.02) but not OS (HR 2.15, 95% C.I. 0.75-6.15, P = 0.15).

CONCLUSION

In patients with HRPBC treated with NAC and adjuvant radiation, increasing ISET is associated with adverse oncologic outcomes.

Systematic risk analysis of radiation pneumonitis in breast cancer: role of cotreatment with chemo-, endocrine, and targeted therapy

PURPOSE

A major complication of sequential and concomitant chemoradiation in breast cancer treatment is interstitial pneumonitis induced by radiation therapy (RT), systemic therapy, or a combination of both. Dose and volume of co-irradiated lung tissue directly correlate with the risk of radiation pneumonitis. Especially in case of combined treatment, it is often unclear which of the used therapeutic agents promote pneumonitis.

METHODS

This was a prospective monocentric study including 396 breast cancer patients. A systematic analysis of single and combined therapeutic measures was performed in order to identify treatment-related factors enhancing the risk of pneumonitis post RT.

RESULTS

Overall incidence of pneumonitis of any grade was 38%; 28% were asymptomatic (grade 1) and 10% were symptomatic (> grade 1). Pneumonitis > grade 2 did not occur. Beside age, smoking status, and mean lung dose, the combined treatment with goserelin and tamoxifen significantly enhanced the risk of pneumonitis in a supra-additive pattern (odds ratio [OR] 4.38), whereas each agent alone or combined with other drugs only nonsignificantly contributed to a higher pneumonitis incidence post RT (OR 1.52 and OR 1.16, respectively). None of the other systemic treatments, including taxanes, increased radiation pneumonitis risk in sequential chemoradiation.

CONCLUSION

Common treatment schedules in sequential chemoradiation following breast-conserving surgery only moderately increase lung toxicity, mainly as an asymptomatic complication, or to a minor extent, as transient pneumonitis ≤ grade 2. However, combined treatment with tamoxifen and the LHRH analog goserelin significantly increased the risk of pneumonitis in breast cancer patients after chemoradiation. Thus, closer surveillance of involved patients is advisable.

Radiotherapy of Breast Cancer—Professional Guideline 1st Central-Eastern European Professional Consensus Statement on Breast Cancer

The international radiotherapy (RT) expert panel has revised and updated the RT guidelines that were accepted in 2020 at the 4th Hungarian Breast Cancer Consensus Conference, based on new scientific evidence. Radiotherapy after breast-conserving surgery (BCS) is indicated in ductal carcinoma in situ (stage 0), as RT decreases the risk of local recurrence (LR) by 50–60%. In early stage (stage I-II) invasive breast cancer RT remains a standard treatment following BCS. However, in elderly (≥70 years) patients with stage I, hormone receptor-positive tumour, hormonal therapy without RT can be considered. Hypofractionated whole breast irradiation (WBI) and for selected cases accelerated partial breast irradiation are validated treatment alternatives to conventional WBI administered for 5 weeks. Following mastectomy, RT significantly decreases the risk of LR and improves overall survival of patients who have 1 to 3 or ≥4 positive axillary lymph nodes. In selected cases of patients with 1 to 2 positive sentinel lymph nodes axillary dissection can be substituted with axillary RT. After neoadjuvant systemic treatment (NST) followed by BCS, WBI is mandatory, while after NST followed by mastectomy, locoregional RT should be given in cases of initial stage III–IV and ypN1 axillary status.

Combination of Modern Radiotherapy and New Targeted Treatments for Breast Cancer Management

Simple Summary

Since the introduction of hormone therapy for the treatment of breast cancer (BC) three decades ago, many new targeted therapies have been developed. Some of them are currently used, such as HER2 inhibitors, while others are still under development, such as cell cycle (CDK) inhibitors, immune checkpoint (PD1/PDL1) inhibitors, or molecules acting on DNA damage (PARP) repair. Besides this, radiation therapy (RT) is commonly used either as adjuvant treatment for early BC after breast conservative surgery or in palliative intent for the treatment of metastatic sites. Our research has shown that the combinations of the most commonly used targeted treatments and RT were feasible with a few toxicities. Nevertheless, most of the knowledge on this subject is based on retrospective studies and a small number of patients and care should be taken in this setting until these results would be confirmed in prospective randomized studies.

Abstract

Background: The objective of the present study was to review the essential knowledge about the combinations of the most commonly used or under development targeted treatments and radiation therapy (RT). Methods: Preclinical and clinical studies investigating this combination were extensively reviewed. Results: Several studies showed that the combination of RT and tamoxifen increased the risk of radiation-induced pulmonary toxicity; therefore, both modalities should not be given concomitantly. The combination of HER2 inhibitors (trastuzumab, pertuzumab) and RT seems to be safe. However, trastuzumab emtansine (T-DM1) should not be administered concurrently with brain RT since this combination could increase the risk of brain radionecrosis. The combination of RT and other new target treatments such as selective estrogen receptor degradants, lapatinib, cell cycle inhibitors, immune checkpoint inhibitors, or molecules acting on DNA damage repair seems feasible but was essentially evaluated on retrospective or prospective studies with a small number of patients. Furthermore, there is considerable heterogeneity among these studies regarding the dose and fractionation of radiation, the dosage of drugs, and the sequence of treatments used. Conclusions: The combination of RT with most targeted therapies for BC appears to be well-tolerated, but these results need to be confirmed in prospective randomized studies.

Pneumonitis and fibrosis after breast cancer radiotherapy: occurrence and treatment-related predictors

BACKGROUND

Radiation pneumonitis (RP) and radiation fibrosis (RF) are common side effects after breast cancer (BC) radiotherapy (RT). However, there is a great variation in the frequency of RP and RF. This study presents the occurrence of- and the treatment-related predictors for RP and RF. Further, physician- and patient-reported pulmonary symptoms during the first year after postoperative RT for BC are demonstrated.

MATERIALS AND METHODS

From 2007 to 2008, 250 BC patients referred for postoperative RT were included in a prospective cohort study and followed during the first year after RT. High-resolution computed tomography of the lungs and symptom registration were performed before RT and 3, 6, and 12 months after RT. Patient-reported symptoms were registered by standard quality of life questionnaires. Logistic regression analyses were applied to estimate treatment-related predictors for radiological RP (rRP), clinical RP (cRP), radiological RF (rRF), and clinical RF (cRF).

RESULTS

The occurrence of rRP and cRP at three months was 78% and 19%, while 12 months after RT rRF and cRF was 89% and 16%, respectively; all reported as grade 1. In multivariable analyses, mastectomy predicted cRP at three months (OR = 2.48, p = .03) and cRF at six months, ipsilateral lung volume receiving 20 Gray or more (V20), V30, and mean lung dose (MLD) predicted rRP at six months (OR = 1.06, p = .0003; OR = 1.10, p = .001; and OR = 1.03, p = .01, respectively). Endocrine treatment predicted cRF at 12 months (OR = 2.48, p = .02). Physicians reported significant more dyspnea at 3 months (p = .003) and patients reported 'a little dyspnea' more at 3 and 12 months compared to baseline (p = .007).

CONCLUSION

RP and RF are prevalent in the first year after BC radiation. Mastectomy predicted cRP at three months. V20, V30, D25, and MLD predicted rRP at 6 months, and endocrine treatment predicted cRF at 12 months. Patients and physicians reported dyspnea differently.

Radiation-Induced Lung Injury-Current Perspectives and Management

Radiotherapy plays an important role in the treatment of localized primary malignancies involving the chest wall or intrathoracic malignancies. Secondary effects of radiotherapy on the lung result in radiation-induced lung disease. The phases of lung injury from radiation range from acute pneumonitis to chronic pulmonary fibrosis. Radiation pneumonitis is a clinical diagnosis based on the history of radiation, imaging findings, and the presence of classic symptoms after exclusion of infection, pulmonary embolism, heart failure, drug-induced pneumonitis, and progression of the primary tumor. Computed tomography (CT) is the preferred imaging modality as it provides a better picture of parenchymal changes. Lung biopsy is rarely required for the diagnosis. Treatment is necessary only for symptomatic patients. Mild symptoms can be treated with inhaled steroids while subacute to moderate symptoms with impaired lung function require oral corticosteroids. Patients who do not tolerate or are refractory to steroids can be considered for treatment with immunosuppressive agents such as azathioprine and cyclosporine. Improvements in radiation technique, as well as early diagnosis and appropriate treatment with high-dose steroids, will lead to lower rates of pneumonitis and an overall good prognosis.

Concurrent Radiation and Modern Systemic Therapies for Breast Cancer: An Ever-Expanding Frontier

Radiotherapy is a critical tool for reducing locoregional recurrence, extending survival, and palliating symptoms in patients with breast cancer. With an ever-expanding armamentarium of systemic agents available, and an increasing trend toward the use of hypofractionated radiation regimens, it can be difficult to determine the safety of concurrent therapy. In particular, new targeted agents in both the adjuvant and metastatic setting have limited prospective or long-term data demonstrating safety when delivered concurrently with radiotherapy. Other systemic agents, including chemotherapy and endocrine therapy, are also important components of the overall treatment strategy for localized and metastatic breast cancer, and are often delivered concurrently with radiation in certain clinical scenarios. This review explores the safety, efficacy, and pitfalls of delivering radiation in conjunction with systemic therapies for breast cancer.

Effect of Adjuvant Hormonal Therapy on the Development of Pulmonary Fibrosis after Postoperative Radiotherapy for Breast Cancer

Breast cancer is the most common malignancy among women. Therefore, it is of paramount importance to study the adverse effects of oncological treatment of breast cancer, with one of adverse effects being pulmonary fibrosis (PF). PF is an irreversible condition and can significantly reduce the quality of life. Following lumpectomy, radiotherapy is the standard adjuvant treatment for breast cancer. Additionally, hormone receptor-positive breast cancers are treated with adjuvant hormonal therapy. While radiotherapy is one of the known causes of PF, the effect of hormone therapy on its development is not well-defined. Some studies have shown that the concomitant administration of endocrine therapy, primarily tamoxifen, and irradiation may potentiate the development of PF. However, guidelines regarding the timing of hormone therapy administration with respect to adjuvant radiotherapy are not clearly defined. This review aims to provide a comprehensive overview of the available information regarding the effect of hormone therapy and its timing of administration with respect to adjuvant radiotherapy on the incidence of PF.

The impact of smoking on adjuvant breast cancer radiation treatment: A systematic review

BACKGROUND

The influence of cigarette smoking on cancer risk has been well-studied. Similarly, exposure to ionizing radiation from radiotherapy (RT) can produce detrimental effects on an individual's health. In patients administered RT, there has been an observed relationship in other primary carcinomas. The purpose of this systematic review was to summarize the influence of cigarette smoking on outcomes post adjuvant RT in breast cancer patients.

METHODS

OVID Medline, Cochrane and Embase were searched and 1893 articles were identified. A total of 71 articles were included in the review. Study type, published year and sample size, age, systemic therapies, RT techniques and treatment side effects were collected if available.

RESULTS

The review found 198 different outcomes which fell into 7 categories and similar outcomes were recorded. 40% of skin reaction outcomes, 50% of cardiovascular outcomes, 71% of reconstruction outcomes, 29% of pulmonary function outcomes, 33% of mortality outcomes and 42% of secondary recurrence outcomes reported significant differences between smokers and non-smokers. None of the articles reported non-smokers to have a higher risk than smokers.

CONCLUSION

Cigarette smoking can pose a higher risk of post-treatment complications that can influence an individual's quality of life, survival rate and/or recurrence risk. This review further assessed the impact of smoking on various patient outcomes and side-effects in the adjuvant breast RT setting. The information provided in this review suggest that smoking cessation programs would help educate patients to understand their risks of being a current or former smoker when undergoing RT.

Optimal sequence of adjuvant endocrine and radiation therapy in early-stage breast cancer - A systematic review

IMPORTANCE

Clinical equipoise exists around the optimal time to start adjuvant endocrine therapy in patients who will receive post-operative radiotherapy for breast cancer. Concerns continue to exist regarding potential reduced efficacy, or increased toxicity, when radiation, and endocrine therapy are administered concurrently.

OBJECTIVE

To perform a systematic review of studies comparing outcomes between sequential and concurrent adjuvant radiation and endocrine therapy in early-stage breast cancer. All modalities of radiation therapy were considered, and endocrine therapy could be either tamoxifen or an aromatase inhibitor. Outcomes of interest included; local, regional or distant recurrence, overall survival and treatment-related toxicities.

EVIDENCE REVIEWED

PubMed, Ovid Medline, EMBASE, and the Cochrane Central Register of Controlled Trials were searched from 1946 to December 2017. Two reviewers independently assessed each citation using the criteria outlined above. Study quality was assessed using the Cochrane Collaboration's tool for prospective studies, and the Newcastle-Ottawa scale for retrospective studies.

FINDINGS

Of 2137 unique citations identified, 13 met eligibility criteria. Eleven were unique studies (7569 patients), while 2 of the studies were updated analyses of previous studies. Studies evaluated the timing of adjuvant radiation, and tamoxifen (5 studies, 1550 patients), or aromatase inhibitors (6 studies, 6019 patients). We identified 1 complete randomized clinical trial (150 patients), and 5 retrospective studies (1580 patients), in addition to conference abstracts (5 studies, 5839 patients). Overall, none of the studies showed a significant difference in efficacy, or toxicity, with concurrent versus sequential treatment. However, given the significant heterogeneity of the study populations, it was not possible to conduct a meta-analysis.

CONCLUSIONS AND RELEVANCE

In the absence of high quality data, adequately powered randomized trials are required to answer this important clinical question.

Estrogen Receptor Signaling in Radiotherapy: From Molecular Mechanisms to Clinical Studies

Numerous studies have established a proof of concept that abnormal expression and function of estrogen receptors (ER) are crucial processes in initiation and development of hormone-related cancers and also affect the efficacy of anti-cancer therapy. Radiotherapy has been applied as one of the most common and potent therapeutic strategies, which is synergistic with surgical excision, chemotherapy and targeted therapy for treating malignant tumors. However, the impact of ionizing radiation on ER expression and ER-related signaling in cancer tissue, as well as the interaction between endocrine and irradiation therapy remains largely elusive. This review will discuss recent findings on ER and ER-related signaling, which are relevant for cancer radiotherapy. In addition, we will summarize pre-clinical and clinical studies that evaluate the consequences of anti-estrogen and irradiation therapy in cancer, including emerging studies on head and neck cancer, which might improve the understanding and development of novel therapeutic strategies for estrogen-related cancers.

A Single Institution Consensus on the Use of Sequential or Concurrent Hormonal Therapy for Breast Cancer Patients Receiving Radiation Therapy

BACKGROUND AND OBJECTIVES

For hormone-sensitive breast cancers, treatment with breast-conserving surgery, tamoxifen, or aromatase inhibitors, along with adjuvant radiation, is the mainstay of therapy. The ideal timing of hormonal and radiation treatment is not well defined, and there is a significant degree of practice variability between concurrent and sequential treatment regimes. This variability can cause confusion amongst the clinical team resulting in contradictory recommendations, loss of patient trust, and the potential for missed initiation of hormonal therapy.

METHODS

To address this question, a systematic review of the literature was conducted and presented to the breast cancer multidisciplinary team at the London Regional Cancer Center. A three-round modified Delphi method was used to obtain a consensus on a series of a priori determined statements.

RESULTS

With the currently available evidence, the consensus was that hormonal therapy should be given sequentially after radiation. This will limit potential overlapping adverse effects between hormonal therapy and radiation that may decrease completion of treatment. The sequential approach has not been associated with any harm in clinical outcomes, and there is some suggestion of increased toxicity with concurrent use. However, in patients at high risk of distant recurrence, they felt it would be reasonable to consider concurrent treatment to avoid any delay in therapy.

CONCLUSION

The consensus of our institution to utilize a sequential approach will standardize the treatment decisions and reduce the risk of failing to initiate hormonal therapy. Despite the lack of level 1 evidence, the Delphi methodology did provide a high level of confidence for our group to choose the sequential approach. The consensus was developed after a review of the literature revealed that there was no clear superiority of one schedule over the other and evidence that concurrent treatment may increase adverse events.

Concurrent or Sequential Hormonal and Radiation Therapy in Breast Cancer: A Literature Review

Background and objectives: Adjuvant hormonal therapy is frequently used in the treatment of women with estrogen receptor (ER)/progesterone receptor (PR) positive breast cancer. When radiotherapy is given, hormone therapy may be delivered in a concurrent or sequential manner. Hormonal blockade with tamoxifen or aromatase inhibitors is thought to arrest hormonally dependent cancer cells in the early G1 phase of the cell cycle. This has been theorized to reduce the efficacy of radiation, which is known to be more effective in cells that are actively dividing. Therefore, there has been a reluctance by many to treat with concurrent hormonal and radiation therapy.

Methods: We performed a search of the Medline database that led to the identification of 39 studies. Abstract and full-text review of these studies led to the identification of seven English non-review studies in peer-reviewed literature between 1995 and 2015 that addressed the question of timing of radiation and hormonal therapy. Outcome measures were captured from each of the studies.

Results: No difference in survival or local-regional recurrence was identified between concurrent versus sequential treatment. Furthermore, no difference in cosmetic outcome or adverse effects was noted for either approach. However, when comparing radiation alone or radiation and hormonal therapy, there was an increased risk of breast and lung fibrosis with combined treatment.

Conclusions: Hormone therapy, concurrent or sequential, with radiation results in comparable disease-related outcomes, including survival and recurrence. However, given the theoretical reduction in efficacy and increased rates of fibrosis with concurrent use, it is reasonable to support the use of sequential therapy.

Pneumonitis and pulmonary fibrosis associated with breast cancer treatments

To review the available published data regarding the incidence, mechanisms of pathogenesis, clinical presentations and management of pneumonitis caused by anti-cancer treatments (radiotherapy (RT) and systemic agents) that are included in the guidelines of the treatment of breast cancer (BC) and address the issues on the current grading classification of pneumonitis. A literature search was performed between July and October 2013 using PubMed for papers published from January 1989 to October 2013. Any clinical trial, case report, case series, meta-analysis or systematic review that reported on pulmonary toxicity of any BC therapeutic modality was included (only papers published in English). Most of anticancer treatments currently used in the management of BC may induce some degree of pneumonitis that is estimated to have an incidence of 1-3 %. There is an obvious distinction between chemotherapy- and targeted treatment-related lung toxicity. Moreover, the current classification of pneumonitis needs to be modified as there is a clear diversity in grade 2. As pneumonitis is relatively common and reported as side effect of new anticancer agents, physicians need to be aware of the clinical and radiological manifestations of drug- and RT-induced toxicities in patients with BC. A key recommendation is the subdivision of grade 2 cases to two subgroups. We provide an algorithm, along with real life cases as managed in the breast Unit of Royal Marsden Hospital, with the aim to guide physicians in managing all possible eventualities that may come across in clinical practise.

Analysis of predictive factors for lung injury after forward-planned intensity-modulated radiotherapy in whole breast irradiation

Purpose

This study was performed to assess frequency, timings of occurrence, and predictors of radiologic lung damage (RLD) after forward-planned intensity-modulated radiotherapy (FIMRT) for whole breast irradiation.

Methods

We retrospectively reviewed medical records of 157 breast cancer patients and each of their serial chest computed tomography (CT) taken 4, 10, 16, and 22 months after completion of breast radiotherapy (RT). FIMRT was administered to whole breast only (n=152), or whole breast and supraclavicular regions (n=5). Dosimetric parameters, such as mean lung dose and lung volume receiving more than 10 to 50 Gy (V₁₀-V₅₀), and clinical parameters were analyzed in relation to radiologic lung damage.

Results

In total, 104 patients (66.2%) developed RLD after whole breast FIMRT. Among the cases of RLD, 84.7% were detected at 4 months, and 15.3% at 10 months after completion of RT. More patients of 47 or younger were found to have RLD at 10 months after RT than patients older than the age (11.7% vs. 2.9%, p=0.01). In univariate and multivariate analyses, age >47 and V₄₀ >7.2% were significant predictors for higher risk of RLD.

Conclusion

RLD were not infrequently detected in follow-up CT after whole breast FIMRT. More detected cases of RLD among younger patients are believed to have developed at later points after RT than those of older patients. Age and V₄₀ were significant predictors for RLD after whole breast intensity-modulated radiotherapy.

Opportunities for rehabilitation of patients with radiation fibrosis syndrome

This review discusses the pathophysiology, evaluation, and treatment of neuromuscular, musculoskeletal, and functional disorders that can result as late effects of radiation treatment. Although radiation therapy is often an effective method of killing cancer cells, it can also damage nearby blood vessels that nourish the skin, ligaments, tendons, muscles, nerves, bones and lungs. This can result in a progressive condition called radiation fibrosis syndrome (RFS). It is generally a late complication of radiotherapy which may manifest clinically years after treatment. Radiation-induced damage can include "myelo-radiculo-plexo-neuro-myopathy," causing muscle weakness and dysfunction and contributing to neuromuscular injury. RFS is a serious and lifelong disorder which, nevertheless, may often be decremented when identified and rehabilitated early enough. This medical treatment should be a complex procedure consisting of education, physical therapy, occupational therapy, orthotics as well as medications.

Relationship between radiation pneumonitis and organizing pneumonia after radiotherapy for breast cancer

BACKGROUND

Radiation pneumonitis (RP) and organizing pneumonia (OP) are the two main types of lung damage that can occur after lung irradiation. The goal of this study was to evaluate the relationship between RP and OP after irradiation for breast cancer.

METHODS

Four hundred and twenty-eight patients who underwent radiotherapy for breast cancer were identified. The whole breast was irradiated with two tangential photon beams. Chest computed tomography (CT) scan were performed when patients showed any symptoms that were suspicious for pneumonitis.

RESULTS

Five patients (1.2%) were diagnosed with OP. All five patients showed ground glass opacities and consolidation of the border of the lesion of RP in the radiation fields. Infiltration of OP spread from the site of RP to the hilum of the ipsilateral lung. Between RP and OP, a free region space (FRS) could be detected.

CONCLUSIONS

OP is closely related to RP. All OP lesions developed near the site of RP.

Correlation of conventional and conformal plan parameters for predicting radiation pneumonitis in patients treated with breast cancer

Purpose

The purpose of this study is to evaluate the correlation between the conventional plan parameters and dosimetric parameters obtained from conformal radiotherapy (RT) planning, and between these parameters and radiation pneumontitis (RP) incidence.

Methods

Clinical and dosimetric data of 122 patients that were treated with mastectomy and adjuvant 3D conformal RT (39% received 2-field RT [2-FRT], and in addition, 61% received 4-field RT [4-FRT]) were retrospectively analyzed. Central lung depth (CLD), maximum lung depth (MLD), and lung length were measured by the conventional plan. Lung dose-volume histograms (DVH) were created with conformal planning, and the lung volumes receiving 5 to 50 Gy (V_5Gy to V_50Gy) were calculated. Minimum (D_min), maximum (D_max), and mean doses (D_mean) for the ipsilateral lung and bilateral lungs were measured by DVH. Correlations between 3D dosimetric data and 2D radiographic parameters were analyzed.

Results

The conventional plan parameters did not significantly differ between 2-FRT and 4-FRT. The conformal plan D_min, D_max, and D_mean values were higher in 4-FRT versus 2-FRT. CLD and MLD were correlated with DVH parameter V_5Gy to V_45Gy values for ipsilateral, as well as bilateral lungs for 2-FRT. MLD and ipsilateral D_mean via 2-FRT planning had the strongest positive correlation (r=0.76, p<0.01). Moderate correlations existed between CLD and ipsilateral and bilateral lung V_5Gy-45Gy, and between MLD and bilateral lung V_5Gy-45Gy values in 2-FRT. Only four patients developed symptomatic RP, 4 with 4-FRT and one with 2-FRT.

Conclusion

The conformal plan parameters were strongly correlated with dose-volume parameters for breast 2-FRT. With only 4 cases of Grade 3 RP observed, our study is limited in its ability to provide definitive guidance, however assuming that CLD is an indicator for RP, V_20Gy could be used as a predictor for RP and for 2-FRT. A well-defined parameters are still required to predict RP in 4-FRT.