The UK Standardisation of Breast Radiotherapy (START) Trial A of radiotherapy hypofractionation for treatment of early breast cancer: a randomised trial

Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: preliminary safety results from the CHHiP randomised controlled trial

BACKGROUND

Prostate cancer might have high radiation-fraction sensitivity, implying a therapeutic advantage of hypofractionated treatment. We present a pre-planned preliminary safety analysis of side-effects in stages 1 and 2 of a randomised trial comparing standard and hypofractionated radiotherapy.

METHODS

We did a multicentre, randomised study and recruited men with localised prostate cancer between Oct 18, 2002, and Aug 12, 2006, at 11 UK centres. Patients were randomly assigned in a 1:1:1 ratio to receive conventional or hypofractionated high-dose intensity-modulated radiotherapy, and all were given with 3-6 months of neoadjuvant androgen suppression. Computer-generated random permuted blocks were used, with risk of seminal vesicle involvement and radiotherapy-treatment centre as stratification factors. The conventional schedule was 37 fractions of 2 Gy to a total of 74 Gy. The two hypofractionated schedules involved 3 Gy treatments given in either 20 fractions to a total of 60 Gy, or 19 fractions to a total of 57 Gy. The primary endpoint was proportion of patients with grade 2 or worse toxicity at 2 years on the Radiation Therapy Oncology Group (RTOG) scale. The primary analysis included all patients who had received at least one fraction of radiotherapy and completed a 2 year assessment. Treatment allocation was not masked and clinicians were not blinded. Stage 3 of this trial completed the planned recruitment in June, 2011. This study is registered, number ISRCTN97182923.

FINDINGS

153 men recruited to stages 1 and 2 were randomly assigned to receive conventional treatment of 74 Gy, 153 to receive 60 Gy, and 151 to receive 57 Gy. With 50·5 months median follow-up (IQR 43·5-61·3), six (4·3%; 95% CI 1·6-9·2) of 138 men in the 74 Gy group had bowel toxicity of grade 2 or worse on the RTOG scale at 2 years, as did five (3·6%; 1·2-8·3) of 137 men in the 60 Gy group, and two (1·4%; 0·2-5·0) of 143 men in the 57 Gy group. For bladder toxicities, three (2·2%; 0·5-6·2) of 138 men, three (2·2%; 0·5-6·3) of 137, and none (0·0%; 97·5% CI 0·0-2·6) of 143 had scores of grade 2 or worse on the RTOG scale at 2 years.

INTERPRETATION

Hypofractionated high-dose radiotherapy seems equally well tolerated as conventionally fractionated treatment at 2 years.

FUNDING

Stage 1 was funded by the Academic Radiotherapy Unit, Cancer Research UK programme grant; stage 2 was funded by the Department of Health and Cancer Research UK.

Biologically effective dose and breast cancer conservative treatment: is duration of radiation therapy really important?

To evaluate if biologically effective dose (BED), and in particular the duration of radiation treatment, has an effect on local relapse risk. Between January 2000 and December 2008 a total of 762 patients with T1-2 N0/+ breast cancer was treated with breast-conserving surgery and radiotherapy, with and without hormone therapy and chemotherapy. Adjuvant radiation therapy was administered to a total dose of 60-66 Gy in 30-33 fractions. The computed BEDs were divided in four groups: <43.1, 43.1-44.9, 45.0-46.1, and >46.1 Gy (A-D, respectively). Kaplan-Meier method was used to calculate local relapse rates. Cox regression method was used to identify prognostic factors of local relapse. Evaluated variables were age, tumor histology, tumor size, surgical margin status, axillary nodal status, tumor grading, adjuvant therapies, adjuvant chemotherapy alone, adjuvant hormone therapy alone, adjuvant anthracyclines, and BEDs values. 8-year local relapse rates were 18.0% for group A, 8.5% for group B, 4.6% for group C, and 2.7% for group D (P=0.008). Multivariate Cox regression analysis showed that BEDs values were associated with higher local relapse risk (P=0.001). In our study, a prolongation of radiotherapy treatment, intended as a lower BED value, after breast-conserving surgery is associated with an increased risk of local relapse. Considering the wide range of results published in other studies, hypofractionation for breast cancer should be considered, at the moment, feasible in selected patients.

First results of the randomised UK FAST Trial of radiotherapy hypofractionation for treatment of early breast cancer (CRUKE/04/015)

BACKGROUND AND PURPOSE

Randomised trials testing 15- or 16-fraction regimens of adjuvant radiotherapy in women with early breast cancer have reported favourable outcomes compared with standard fractionation. To evaluate hypofractionation further, two 5-fraction schedules delivering 1 fraction per week have been tested against a 25-fraction regimen.

MATERIALS AND METHODS

Women aged ⩾50years with node negative early breast cancer were randomly assigned after microscopic complete tumour resection to 50Gy in 25 fractions versus 28.5 or 30Gy in 5 once-weekly fractions of 5.7 or 6.0Gy, respectively, to the whole breast. The primary endpoint was 2-year change in photographic breast appearance.

RESULTS

Nine hundred and fifteen women were recruited from 2004 to 2007. Seven hundred and twenty-nine patients had 2-year photographic assessments. Risk ratios for mild/marked change were 1.70 (95% CI 1.26-2.29, p<0.001) for 30Gy and 1.15 (0.82-1.60, p=0.489) for 28.5Gy versus 50Gy. Three-year rates of physician-assessed moderate/marked adverse effects in the breast were 17.3% (13.3-22.3%, p<0.001) for 30Gy and 11.1% (7.9-15.6%, p=0.18) for 28.5Gy compared with 9.5% (6.5-13.7%) after 50Gy. With a median follow-up in survivors of 37.3months, 2 local tumour relapses and 23 deaths have occurred.

CONCLUSIONS

At 3years median follow-up, 28.5Gy in 5 fractions is comparable to 50Gy in 25 fractions, and significantly milder than 30Gy in 5 fractions, in terms of adverse effects in the breast.

Accelerated Partial Breast Irradiation: Using the CyberKnife as the Radiation Delivery Platform in the Treatment of Early Breast Cancer

We evaluate the CyberKnife (Accuray Incorporated, Sunnyvale, CA, USA) for non-invasive delivery of accelerated partial breast irradiation (APBI) in early breast cancer patients. Between 6/2009 and 5/2011, nine patients were treated with CyberKnife APBI. Normal tissue constraints were imposed as outlined in the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 (NSABP/RTOG) Protocol (Vicini and White, 2007). Patients received a total dose of 30 Gy in five fractions (group 1, n = 2) or 34 Gy in 10 fractions (group 2, n = 7) delivered to the planning treatment volume (PTV) defined as the clinical target volume (CTV) +2 mm. The CTV was defined as either the lumpectomy cavity plus 10 mm (n = 2) or 15 mm (n = 7). The cavity was defined by a T2-weighted non-contrast breast MRI fused to a planning non-contrast thoracic CT. The CyberKnife Synchrony system tracked gold fiducials sutured into the cavity wall during lumpectomy. Treatments started 4-5 weeks after lumpectomy. The mean PTV was 100 cm(3) (range, 92-108 cm(3)) and 105 cm(3) (range, 49-241 cm(3)) and the mean PTV isodose prescription line was 70% for groups 1 and 2, respectively. The mean percent of whole breast reference volume receiving 100 and 50% of the dose (V(100) and V(50)) for group 1 was 11% (range, 8-13%) and 23% (range, 16-30%) and for group 2 was 11% (range, 7-14%) and 26% (range, 21-35.0%), respectively. At a median 7 months follow-up (range, 4-26 months), no acute toxicities were seen. Acute cosmetic outcomes were excellent or good in all patients; for those patients with more than 12 months follow-up the late cosmesis outcomes were excellent or good. In conclusion, the lack of observable acute side effects and current excellent/good cosmetic outcomes is promising. We believe this suggests the CyberKnife is a suitable non-invasive radiation platform for delivering APBI with achievable normal tissue constraints.

Toxicity and cosmesis outcomes after single fraction partial breast irradiation in early stage breast cancer

Background

To report the clinical outcome after a Single Shot 3D-CRT PBI (SSPBI) in breast cancer patients after conservative surgery (ClinicalTrials.gov Identifier: NCT01316328).

Methods

A dose of 18Gy (in the first 4 patients) and 21Gy (in the remaining 60 patients) was prescribed in a single session and delivered to the index area (i.e. the area of breast including the primary tumor bed and the surrounding tissue) using 3D-CRT with patients in prone position. Acute and late toxicity was assessed using the National Cancer Institute's CTC for Adverse Events. Cosmesis was defined based on modified Harvard criteria. Differences between dosimetric or clinical parameters of patients with/without G2 or more late toxicity or unsatisfactory (poor or fair) cosmetic outcome were evaluated with the Mann-Whitney test. Odds ratios and 95% confidence interval were calculated for cosmesis and fibrosis. Univariate and multivariate analyses(UVA/MVA) were used to determine covariates associated with an increase in fibrosis or fat necrosis rate.

Results

Sixty four patients were enrolled. With a median follow-up of 3 years, G2 and G3 subcutaneous fibrosis was detected in 20(31%) and in 8(13%) patients, and ≥G2 fat necrosis was observed in 2(3%) patients. Good to excellent, fair and poor cosmesis was observed in 38(59%), 23(36%) and 3(5%) patients, respectively. Based on UVA, the breast volume receiving more than 21Gy (V₂₁Gy) was found to be a predictor of the ≥G1 or ≥G2 fibrosis/fat necrosis. Based on MVA, V₂₁Gy was confirmed as a predictor for ≥G1 fibrosis/fat necrosis, the results correlated as a trend for ≥G2. Cosmesis was correlated with whole breast (WB) mean dose (p = 0.030).

Conclusion

Our choice of a single dose of 21Gy significantly increased the treatment related toxicity. However, this should not discourage novel SSPBI approaches with lower equivalent doses.

Risk factors of developing long-lasting breast pain after breast cancer radiotherapy

PURPOSE

Postoperative radiotherapy decreases breast cancer mortality. However, studies have revealed a long-lasting breast pain among some women after radiotherapy. The purpose of this study was to identify risk factors that contribute to breast pain after breast cancer radiotherapy.

METHODS AND MATERIALS

We identified 1,027 recurrence-free women in two cohorts of Swedish women treated for breast cancer. The women had breast-conserving surgery and postoperative radiotherapy, the breast was treated to 48 Gy in 2.4-Gy fractions or to 50 Gy in 2.0-Gy fractions. Young women received a boost of up to 16 Gy. Women with more than three lymph node metastases had locoregional radiotherapy. Systemic treatments were given according to health-care guidelines. Three to 17 years after radiotherapy, we collected data using a study-specific questionnaire. We investigated the relation between breast pain and potential risk modifiers: age at treatment, time since treatment, chemotherapy, photon energy, fractionation size, boost, loco-regional radiotherapy, axillary surgery, overweight, and smoking.

RESULTS

Eight hundred seventy-seven women (85%) returned the questionnaires. Among women up to 39 years of age at treatment, 23.1% had breast pain, compared with 8.7% among women older than 60 years (RR 2.66; 95% CI 1.33-5.36). Higher age at treatment (RR 0.96; 95% CI 0.94-0.98, annual decrease) and longer time since treatment (RR 0.93; 95% CI 0.88-0.98, annual decrease) were related to a lower occurrence of breast pain. Chemotherapy increased the occurrence of breast pain (RR 1.72; 95% CI 1.19-2.47). In the multivariable model only age and time since treatment were statistically significantly related to the occurrence of breast pain. We found no statistically significant relation between breast pain and the other potential risk modifiers.

CONCLUSIONS

Younger women having undergone breast-conserving surgery with postoperative radiotherapy report a higher occurrence of long-lasting breast pain compared to older women. Time since treatment may decrease the occurrence of pain.

Late Toxicity of Radiotherapy: A Problem or a Challenge for the Radiation Oncologist?

BACKGROUND: Large randomized clinical trials have established radiotherapy in conjunction with adjuvant systemic treatment as standard treatment in breast cancer after both mastectomy and lumpectomy. Although standard radiation therapy is well tolerated by the majority of patients, some patients might suffer from late normal tissue effects. METHODS: The literature on radiotherapy following surgery of breast cancer was reviewed with regard to late toxicity. RESULTS: Radiotherapy may, to some degree, cause persistent pain in the breast, arm and shoulder in up to 30-50% of patients after 3-5 years, lymphedema in 15-25%, and restriction of arm and shoulder movement in 35%. Awareness of cardiotoxicity is needed since anthracyclines, trastuzumab, and radiotherapy may cause damage to the heart. However, using modern radiotherapy techniques, the available evidence does not suggest a higher incidence of cardiac mortality. CONCLUSIONS: This review updates the database on toxicity from radiation in breast cancer. Advances in research of radiation-induced late effects may lead to improved treatment choices for breast cancer patients including radiotherapy and may improve quality of life after surviving breast cancer.

Emerging radiation techniques for early-stage breast cancer after breast-conserving surgery

Standard whole-breast irradiation consisting of a dose of 45-50 Gy over 5 weeks with or without the addition of a boost to the tumor bed has equivalent survival to mastectomy and is considered to be the standard of care for most patients with early-stage breast cancer. Newer techniques have been developed to shorten the course of radiation or limit normal tissue exposure in an attempt to increase accessibility to and tolerance of radiation therapy. This article will review some of the newer regimens and techniques for treating early-stage breast cancer after breast-conserving surgery.

Feasibility and acute toxicity of hypofractionated radiation in large-breasted patients

PURPOSE

To determine the feasibility of and acute toxicity associated with hypofractionated whole breast radiation (HypoRT) after breast-conserving surgery in patients excluded from or underrepresented in randomized trials comparing HypoRT with conventional fractionation schedules.

METHODS AND MATERIALS

A review was conducted of all patients consecutively treated with HypoRT at the University of Chicago. All patients were treated to 42.56 Gy in 2.66 Gy daily fractions in either the prone or supine position. Planning was performed in most cases using wedges and large segments or a "field-in-field" technique. Breast volume was estimated using volumetric measurements of the planning target volume (PTV). Dosimetric parameters of heterogeneity (V105, V107, V110, and maximum dose) were recorded for each treatment plan. Acute toxicity was scored for each treated breast.

RESULTS

Between 2006 and 2010, 78 patients were treated to 80 breasts using HypoRT. Most women were overweight or obese (78.7%), with a median body mass index of 29.2 kg/m(2). Median breast volume was 1,351 mL. Of the 80 treated breasts, the maximum acute skin toxicity was mild erythema or hyperpigmentation in 70.0% (56/80), dry desquamation in 21.25% (17/80), and focal moist desquamation in 8.75% (7/80). Maximum acute toxicity occurred after the completion of radiation in 31.9% of patients. Separation >25 cm was not associated with increased toxicity. Breast volume was the only patient factor significantly associated with moist desquamation on multivariable analysis (p = 0.01). Patients with breast volume >2,500 mL experienced focal moist desquamation in 27.2% of cases compared with 6.34% in patients with breast volume <2,500 mL (p = 0.03).

CONCLUSIONS

HypoRT is feasible and safe in patients with separation >25 cm and in patients with large breast volume when employing modern planning and positioning techniques. We recommend counseling regarding expected increases in skin toxicity in women with a PTV volume >2,500 mL.

Sentinel lymph node biopsy after previous axillary surgery: A review

BACKGROUND

The utility of axillary lymph node dissection (ALND) in the management of breast cancer is currently under close scrutiny. At primary diagnosis the use of sentinel lymph node biopsy (SLNB) has restricted ALND for proven nodal disease, however the management of the axilla at local (in-breast) relapse is less clearly defined with many undergoing routine ALND. This review examines the role of SLNB in the re-operative setting with the objective of developing an axillary management algorithm for use at in-breast local relapse, and restricting ALND to node-positive recurrent cancers.

METHODS

We reviewed published reports of SLNB at local relapse in women who had previously undergone axillary surgery either as lymph node biopsy, SLNB, axillary sampling (AS) or axillary lymph node dissection (ALND).

RESULTS

There have been no randomised trials. Six reports with 327 cases were identified; of which 61% (199/327) had previous SLNB or ALND with <9 nodes removed. There was an overall successful sentinel lymph node (SLN) localisation at re-operation of 69% (227/327), range of 51-100%. In patients who have previously had limited axillary surgery (<9 nodes removed), the rate of successful SLN localisation was 83% (165/199), range of 68-100% and 142/165 (86%, range 80-100%) were node negative. In these highly selected patients no axillary recurrences were noted in those who had a negative SLN at re-operation after 26-46 months follow up.

CONCLUSION

SLNB at in-breast relapse is feasible and safe with successful localisation related to the extent of previous axillary surgery.

Out-of-pocket costs for accessing adjuvant radiotherapy among Canadian women with breast cancer

PURPOSE

Patients with breast cancer incur out-of-pocket costs when they receive adjuvant radiation. These treatments are administered in dedicated centers on a daily basis over 4 to 5 weeks. We assessed the extent of out-of-pocket costs to access radiotherapy and identified women at risk of experiencing higher costs.

PATIENTS AND METHODS

This prospective study was conducted among 800 women from eight Quebec hospitals (participation, 86%), of whom 693 women received adjuvant radiotherapy. Costs to access treatment (transportation, parking, lodging, and meals) were estimated on the basis of information collected by telephone interviews. Generalized linear models were used to identify women at risk of having higher costs.

RESULTS

Mean and median total costs (including financial aid received) to access radiotherapy were 445 Canadian dollars (Can$; standard deviation, Can$407) and Can$311, respectively. Women who lived at home but far from the radiotherapy center had the highest risk of experiencing weekly costs of at least Can$122 (highest quartile; prevalence ratio [PR], 5.8; 95% CI, 4.7 to 7.1) followed by women who lived away from home and farther from the center (PR, 4.5; 95% CI, 3.4 to 6.0) and by women who lived away from home and closer to the center (PR, 2.14; 95% CI, 1.3 to 3.5). When women stayed at a cancer lodge during treatment, costs were reduced by 80%.

CONCLUSION

Considered in and of themselves, out-of-pocket costs for access to radiotherapy appeared relatively modest. Financial assistance initiatives for women who lived away from home during treatments contributed to a substantial reduction of access costs. These efforts should be maintained, but financial assistance should also target patients with cancer who live at home during treatments but have to travel relatively long distances on a daily basis.

Optimization of Adjuvant Radiation in Breast Conservation Therapy: Can We Minimize without Compromise?

Adjuvant breast radiation therapy after breast conservation surgery is recommended as it yields significant reduction in the risk of local recurrence, and confers a potential overall survival benefit. Although the standard breast radiation regimen has historically been delivered over 5-7 weeks; more novel, shorter courses of breast radiation are currently being employed, offering the advantage of more convenience and less time-commitment. Herein, we review the recent literature substantiating these abbreviated radiation treatment approaches and the methods of delivery thereof. In addition, we discuss imaged guided techniques currently being utilized to further refine the delivery of adjuvant breast radiation therapy.

The evolution of the locoregional therapy of breast cancer

Breast-conserving therapy (BCT) and mastectomy have equal survival outcomes. Rates of local recurrence after BCT have declined steadily, largely as a result of the widespread use of systemic therapy. Sentinel node biopsy has replaced axillary dissection for staging the axilla, and in women undergoing BCT with whole-breast irradiation (WBI), axillary dissection is not needed for local control or survival in those with fewer than three involved sentinel nodes. Alternatives to 6 weeks of WBI have been shown to be safe and effective for subsets of breast cancer patients, and the use of preoperative chemotherapy allows BCT in some women who require mastectomy if surgery is the initial step in treatment. The combination of the smaller cancers detected with screening and the routine use of multimodality therapy has resulted in a decrease in the morbidity of local therapy and improved cancer treatment outcomes.

Assessment of contralateral mammary gland dose in the treatment of breast cancer using accelerated hypofractionated radiotherapy

AIM: To measure the dose distribution, related to the treatment planning calculations, in the contralateral mammary gland of breast cancer patients treated with accelerated hypofractionated 3-dimensional conformal radiotherapy.

METHODS: Thirty-four prospectively selected female patients with right breast cancer (pN0, negative surgical margins) were treated with breast-conserving surgery. A total dose of 42.5 Gy (2.66 Gy/fraction) was prescribed; it was requested that planning target volumes be covered by the 95% isodose line. The contralateral mammary gland was defined on CT simulation. The dose received was evaluated by dose volume histograms.

RESULTS: The measured contralateral breast doses were: (1) Dose maximum: 290-448 cGy [Equivalent (Eq) 337-522 cGy]; (2) Mean dose: 45-70 cGy (Eq 524-815 cGy); and (3) Median dose: 29-47 cGy (337-547 cGy) for total primary breast dose of 42.5 Gy in 16 equal fractions. The spearman rho correlation showed statistical significance between the contralateral breast volume and maximum dose (P = 0.0292), as well as mean dose (P = 0.0025) and median dose (P = 0.046) to the breast.

CONCLUSION: Minimizing the dose to the contralateral breast has to be one of the priorities of the radiation oncologist when using short schedules because of the radiosensitivity of this organ at risk. Further study is necessary to assess the long-term clinical impact of this schedule.

[Exclusive radiotherapy and concurrent endocrine therapy for the management of elderly breast cancer patients: case study and review of hypofractionated schemes]

Normofractionated radiotherapy is standard for adjuvant management of patients treated with breast conservative surgery for breast cancer. However, many elderly patients are not eligible to such strategy, either because of concurrent diseases, or because the tumor is inoperable. Several protocols of exclusive radiotherapy have been reported in the literature, frequently using hypofractionated radiotherapy and endocrine therapy. We report a case of a patient treated with exclusive endocrine and radiotherapy and address the state of the art on hypofractionated schemes for the management of elderly breast cancer patients. While hypofractionated radiotherapy does not compromise the oncologic or cosmetic outcome, there is no prospective data that assesses the place of radiotherapy for the exclusive treatment of elderly patients. This strategy should be further assessed in clinical randomized trial.

ACR Appropriateness Criteria® conservative surgery and radiation--stage I and II breast carcinoma: expert panel on radiation oncology: breast

Breast conservation is a safe and effective alternative to mastectomy for the majority of women with early-stage breast cancer. Adjuvant radiation therapy lowers the risk of recurrence within the breast and also confers a survival benefit. Although acute side effects of radiation therapy are generally well tolerated; efforts are ongoing to minimize the long-term side effects of radiation, most prominently atherosclerotic heart disease. Efforts to minimize radiation therapy are also underway. They include omitting treatment altogether in the elderly and using accelerated, hypofractionated whole-breast irradiation, and accelerated partial-breast irradiation. Several randomized studies are ongoing to determine the efficacy, safety, and appropriate patients for these shorter treatments.

The role of ipsilateral breast radiotherapy in management of occult primary breast cancer presenting as axillary lymphadenopathy

AIM

To assess the role of ipsilateral breast radiotherapy (IBR) in women with occult primary breast cancer presenting with axillary metastases (OPBC).

METHODS

Patients with axillary nodal metastases and histological diagnosis of breast cancer without palpable, mammographic or ultrasonographic evidence of a breast primary were identified from a prospectively maintained single institution database. Imaging, surgery, radiotherapy, recurrence and survival data were collected. Patients whose breast cancer primary was detected on MRI (but occult on clinical examination and other imaging) were excluded from the analyses of IBR and outcome, but were included in other exploratory analyses.

RESULTS

Fifty-five patients were included between 1975 and 2009. Median follow up was 68 months. Twenty patients had breast magnetic resonance imaging (MRI) in addition to other imaging. A primary breast cancer was detected in 7 of these 20. 48/55 patients had no detectable breast primary. 35/48 patients (73%) were treated with radiotherapy to the conserved breast, and 13/48 (27%) with observation. Patients who had IBR had better 5 year local recurrence free survival (LRFS) (84% versus 34%, p<0.001), and relapse free survival (RFS) (64% versus 34%, p=0.05), but no difference in overall survival (OS) (84% versus 85%, p=0.2). There was no difference in 5 year LRFS (80% versus 90%: p=0.3) between patients who received radiation of 50 Gy in 25 fractions versus ≥60 Gy.

CONCLUSION

Patients with OPBC should be managed with IBR and breast conservation, or mastectomy. Our data suggest it is not necessary to irradiate the breast to more than 50 Gy in 25 fractions.

The Cambridge Breast Intensity-modulated Radiotherapy Trial: patient- and treatment-related factors that influence late toxicity

AIMS

The effect of patient- and treatment-related factors in the development of late normal tissue toxicity after radiotherapy is not yet fully established. The aim of this study was to elucidate the relative importance of such factors in the development of late toxicity after breast-conserving surgery and adjuvant breast radiotherapy.

MATERIALS AND METHODS

Patient- and treatment-related factors were analysed in 1014 patients who had received adjuvant radiotherapy to the breast in the Cambridge Breast Intensity-modulated Radiotherapy (IMRT) Trial. Late toxicity data were collected using photographic and clinical assessments and patient-reported questionnaires at 2 years after radiotherapy.

RESULTS

On multivariate analysis, a larger breast volume was statistically significantly associated with the development of breast shrinkage assessed by serial photographs (odds ratio per litre increase in breast volume = 1.98, 95% confidence interval 1.41, 2.78; P < 0.0005), telangiectasia (odds ratio = 3.94, 95% confidence interval 2.49, 6.24; P < 0.0005), breast oedema (odds ratio = 3.65, 95% confidence interval 2.54, 5.24; P < 0.0005) and pigmentation (odds ratio = 1.75, 95% confidence interval 1.21, 2.51; P = 0.003). Current smokers had an increased risk of developing pigmentation (odds ratio = 2.09, 95% confidence interval 1.23, 3.54; P = 0.006). Patients with a moderate or poor post-surgical cosmesis had a greatly increased risk of moderate or poor overall cosmesis (odds ratio = 38.19; 95% confidence interval 21.9, 66.7; P < 0.0005). Postoperative infection requiring antibiotics was associated with increased risk of telangiectasia (odds ratio = 3.39, 95% confidence interval 1.94, 5.91; P < 0.0005) and breast oversensitivity (odds ratio = 1.78, 95% confidence interval 1.27, 2.49; P = 0.001).

CONCLUSIONS

In this study, the greatest risk factors for the development of late toxicity 2 years after breast-conserving surgery and adjuvant radiotherapy were larger breast volume, baseline pre-radiotherapy surgical cosmesis, postoperative infection and possibly smoking. These factors seem to be more important than relatively small differences in dose inhomogeneity and the addition of boost radiotherapy at 2 years after the completion of radiotherapy. The modification of potentially preventable risk factors, such as postoperative infection and smoking, may limit the development of late toxicity after breast radiotherapy.

Adjuvant therapy for women over age 65 with breast cancer

BACKGROUND

Women over age 65 with breast cancer are often not treated in accordance with current guidelines as far as adjuvant therapy is concerned, because of the lack of adequate scientific evidence.

METHODS

This article is based on a selective review of pertinent literature retrieved by a PubMed search, as well as on the German S3 guidelines for the diagnosis, treatment, and follow-up care of breast cancer, the treatment recommendations of the German Working Group on Gynecological Oncology (Arbeitsgemeinschaft Gynäkologische Onkologie, AGO) and the German Society of Radiation Oncology (Deutsche Gesellschaft für Radioonkologie), US National Comprehensive Cancer Network, and the Cochrane database.

RESULTS

Women over age 65 are underrepresented in randomized trials of treatments for breast cancer. Geriatric assessment is essential for therapeutic decision-making. Endocrine treatment is feasible for nearly all patients with hormone-sensitive tumors. In selected patients over age 65, chemotherapy significantly improves overall survival. The best evidence regarding toxicity is available for anthracycline monotherapy and for combined therapy with doxorubicin/cyclophosphamide or taxane/doxorubicin. Women without cardiac disease can be given trastuzumab, which may lead to reversible cardiotoxicity. Adjuvant radiotherapy significantly improves local tumor control and survival. Adjuvant radiotherapy that is carried out with modern treatment planning, as recommended by the current guidelines, is no more toxic to older patients than to younger ones; thus, it should always be given, unless there is a special reason not to.

CONCLUSION

Women with breast cancer over age 65 whose life expectancy is greater than 5 years, and who are not otherwise too ill, should be given chemotherapy, trastuzumab, and radiotherapy as standard adjuvant treatment. Adjuvant therapy can be reduced or omitted in frail patients. Patients over age 65 should be given the opportunity to enroll in clinical trials.

Radiobiological rationale and clinical implications of hypofractionated radiation therapy

Recent clinical trials of hypofractionated radiation treatment have provided critical insights into the safety and efficacy of hypofractionation. However, there remains much controversy in the field, both at the level of clinical practice and in our understanding of the underlying radiobiological mechanisms. In this article, we review the clinical literature on hypofractionated radiation treatment for breast, prostate, and other malignancies. We highlight several ongoing clinical trials that compare outcomes of a hypofractionated approach versus those obtained with a conventional approach. Lastly, we outline some of the preclinical and clinical evidence that argue in favor of differential radiobiological mechanisms underlying hypofractionated radiation treatment. Emerging data from the ongoing studies will help to better define and guide the rational use of hypofractionation in future years.

Roles and types of radiation in breast cancer treatment: early breast cancer, locoregionally advanced, and metastatic disease

PURPOSE OF REVIEW

To describe the current role of radiation therapy and specific types of radiation therapy used in the management of early stage, locoregionally advanced, and metastatic breast cancer.

RECENT FINDINGS

The role of radiation therapy in the management of breast cancer has not changed in recent decades, however methods of treatment delivery have advanced considerably. Hypofractionation and accelerated partial breast irradiation, which substantially reduce radiation treatment duration, have emerged as appropriate alternatives to conventional whole breast radiation in select patient subsets, and intensity modulated radiation therapy, breathing-adapted radiation therapy, and prone-positioning technique address challenging anatomic issues and reduce treatment-associated toxicity. Stereotactic radiosurgery and stereotactic body radiation therapy continue to advance the management of distant metastatic disease.

SUMMARY

Radiation therapy plays a significant role in the management of early stage, locoregionally advanced, and metastatic breast cancer. Technological advances are allowing for greater patient convenience and comfort in locoregional radiation therapy delivery and for expanded radiation therapy indications in the setting of metastatic disease.

Is α/β for breast cancer really low?

PURPOSE

Low α/β ratio for breast cancer has drawn a growing interest for exploring hypofractionation for breast irradiation. This work is to confirm the low α/β ratio based on large randomized clinical trials of breast irradiation.

METHODS AND MATERIALS

A model based on the generalized linear-quadratic (LQ) model and Poisson statistical model was developed to calculate disease-free survival with consideration of clonogen proliferation during the course of radiation treatment and exponential behavior of survival rate with follow-up time. Outcome data from a series of randomized clinical trials of early-stage breast radiotherapy were fitted to estimate the model parameters. Other clinical outcomes, including treatments with surgery alone or radiotherapy alone were used to validate the model and the estimated parameters. Hypofractionation regimens were proposed based on the newly estimated LQ parameters.

RESULTS

Plausible population averaged radiobiologic parameters for breast cancer (95% confidence level) are α/β=2.88 (0.75-5.01) Gy; α=0.08±0.02Gy(-1); potential doubling time T(d)=14.4±7.8day. The analysis of the radiation-alone data suggested an α/β ratio of 3.89±6.25Gy, verifying the low α/β ratio based on the post-lumpectomy irradiation data. The hypofractionation regimens that are equivalent to the conventional regimen of 2.0Gy×25 in 5weeks include 2.26Gy×20, 3.34Gy×10, 4.93Gy×5 or 3.39Gy×10 (BID).

CONCLUSIONS

The analysis of the available clinical data from multiple institutions support that breast cancer has a low ratio of α/β, encouraging hypofractionated radiotherapy regimens for breast cancer.

Randomized controlled trial of forward-planned intensity modulated radiotherapy for early breast cancer: interim results at 2 years

PURPOSE

This single-center randomized trial was designed to investigate whether intensity-modulated radiotherapy (IMRT) reduces late toxicity in patients with early-stage breast cancer.

METHODS AND MATERIALS

The standard tangential plans of 1,145 nonselected patients were analyzed. The patients with inhomogeneous plans were randomized to a simple method of forward-planned IMRT or standard radiotherapy (RT). The primary endpoint was serial photographic assessment of breast shrinkage.

RESULTS

At 2 years, no significant difference was found in the development of any photographically assessed breast shrinkage between the patients randomized to the interventional or control group (odds ratio, 1.51; 95% confidence interval, 0.83-1.58; p = .41). The patients in the control group were more likely to develop telangiectasia than those in the IMRT group (odds ratio, 1.68; 95% confidence interval 1.13-2.40; p = .009). Poor baseline surgical cosmesis resulted in poor overall cosmesis at 2 years after RT. In patients who had good surgical cosmesis, those randomized to IMRT were less likely to deteriorate to a moderate or poor overall cosmesis than those in the control group (odds ratio, 0.63; 95% confidence interval, 0.39-1.03, p = .061).

CONCLUSIONS

IMRT can lead to a significant reduction in telangiectasia at comparatively early follow-up of only 2 years after RT completion. An important component of breast induration and shrinkage will actually result from the surgery and not from the RT. Surgical cosmesis is an important determinant of overall cosmesis and could partially mask the longer term benefits of IMRT at this early stage.

Radiobiological characterization of post-lumpectomy focal brachytherapy with lipid nanoparticle-carried radionuclides

Post-operative radiotherapy has commonly been used for early stage breast cancer to treat residual disease. The primary objective of this work was to characterize, through dosimetric and radiobiological modeling, a novel focal brachytherapy technique which uses direct intracavitary infusion of β-emitting radionuclides (186Re/188Re) carried by lipid nanoparticles (liposomes). Absorbed dose calculations were performed for a spherical lumpectomy cavity with a uniformly injected activity distribution using a dose point kernel convolution technique. Radiobiological indices were used to relate predicted therapy outcome and normal tissue complication of this technique with equivalent external beam radiotherapy treatment regimens. Modeled stromal damage was used as a measure of the inhibition of the stimulatory effect on tumor growth driven by the wound healing response. A sample treatment plan delivering 50 Gy at a therapeutic range of 2.0 mm for 186Re-liposomes and 5.0 mm for 188Re-liposomes takes advantage of the dose delivery characteristics of the β-emissions, providing significant EUD (58.2 Gy and 72.5 Gy for 186Re and 188Re, respectively) with a minimal NTCP (0.046%) of the healthy ipsilateral breast. Modeling of kidney BED and ipsilateral breast NTCP showed that large injected activity concentrations of both radionuclides could be safely administered without significant complications.

Test of association between variant tgβ1 alleles and late adverse effects of breast radiotherapy

PURPOSE

To test for association between single nucleotide polymorphisms at the TGFβ1 locus and the risk of late normal tissue injury following whole breast radiotherapy.

METHODS

A retrospective study compared the number of variant alleles at -509 and codons 10 and 25 of the TGFβ1 locus in women followed up in two prospective clinical trials who developed either marked radiotherapy adverse effects or no adverse effects after matching on fractionation schedule, breast size, surgical deficit, chemotherapy and length of follow up.

RESULTS

Median follow up in the two trials was 7.4 (maximum 15) years and 5.3 (maximum 5.3) years. 1237/1716 (72%) women with photographic assessments of radiotherapy adverse effects were alive and well, and 147/1237 (12%) potential cases with the most marked change in photographic change in breast appearance were matched to potential controls recording no change. In an unmatched analysis of 82 cases and 108 controls, no significant difference in the number of genetic variants was observed.

CONCLUSIONS

No association was detected between sequence variations at the TGFβ1 locus and the risk of late adverse effects of breast radiotherapy.

Patient preferences and physician practice patterns regarding breast radiotherapy

PURPOSE

There are multiple current strategies for breast radiotherapy (RT). The alignment of physician practice patterns with best evidence and patient preferences will enhance patient autonomy and improve cancer care. However, there is little information describing patient preferences for breast RT and physician practice patterns.

METHODS AND MATERIALS

Using a reliable and valid instrument, we assessed the preferences of 5,000 randomly selected women (with or without cancer) undergoing mammography. To assess practice patterns, 2,150 randomly selected physician-members of American Society for Radiation Oncology were surveyed.

RESULTS

A total of 1,807 women (36%) and 363 physicians (17%) provided usable responses. The 95% confidence interval is < ± 2.3% for patients and < ± 5.3% for physicians. Patient preferences were hypofractionated whole breast irradiation (HF-WBI) 62%, partial breast irradiation (PBI) 28%, and conventionally fractionated whole breast irradiation (CF-WBI) 10%. By comparison, 82% of physicians use CF-WBI for more than 2/3 of women and 56% never use HF-WBI. With respect to PBI, 62% of women preferred three-dimensional (3D)-PBI and 38% favor brachytherapy-PBI, whereas 36% of physicians offer 3D-PBI and 66% offer brachytherapy-PBI. 70% of women prefer once-daily RT over 10 days vs. twice-daily RT over 5 days. 55% of physicians who use PBI do not offer PBI on clinical trial.

CONCLUSIONS

HF-WBI, while preferred by patients and supported by evidence, falls behind the unproven and less preferred strategy of PBI in clinical practice. There is a discrepancy between women's preferences for PBI modality and type of PBI offered by physicians. Further alignment is needed between practice patterns, patient preferences, and clinical evidence.

Effects of radiotherapy fractionation on breast stromal activity

We study the dynamics of tumor cell progression as growth factors and ionizing radiation (IR) combine to modify cellular microenvironments. Breast tumor growth depends on the behavior of cancer cells in their microenvironment, and both components are affected by IR fractionation parameters. TGF-β1 promotes differentiation of fibroblasts to myofibroblasts, which stiffens the extracellular matrix (ECM) and promotes malignant cell phenotypes. IR generates reactive oxygen species (ROS) that damages and inactivates cells thus controlling proliferation. The effects of TGF-β1 and IR at various fraction sizes on ECM stiffness and fibroblast differenation are studied using MRC-5 fibroblasts in 3-D collagen cultures.

Hypofractionated radiotherapy and adjuvant chemotherapy do not increase radiation-induced dermatitis in breast cancer patients

PURPOSE

Radiation-induced dermatitis is a common side effect of breast irradiation, with hypofractionation being a well-known risk factor. In the context of the widespread adoption of hypofractionated breast radiotherapy, we evaluated the effect of hypofractionated radiotherapy on the incidence of skin toxicity in patients receiving adjuvant chemotherapy.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients with breast cancer treated from 2004 to 2006 at a single institution. Patients undergoing lumpectomy with or without adjuvant chemotherapy followed by hypofractionated radiotherapy consisting of 42.4 Gy in 16 fractions were included in the study. Using cosmetic and skin toxicity scales, all patients were evaluated weekly during treatment and at scheduled follow-up visits with the radiation oncologist.

RESULTS

During the study period, 162 patients underwent radiotherapy, and 30% of those (n = 48) received chemotherapy. Radiotherapy boost to the tumour bed was more common in the chemotherapy group [n = 20 (42%)] than in the radiotherapy-alone group [n = 30 (26%)]. We observed no statistically significant difference between the groups with regard to acute skin toxicity of grade 3 or higher (2.1% in the chemotherapy group vs. 4.4% in the radiation-alone group, p = 0.67) or of grades 1-2 toxicity (62.5% vs. 51.7% respectively, p = 0.23). There was also no significant difference in late grade 3 or higher skin toxicity between the groups (2.1% vs. 0% respectively, p = 0.30) or in grades 1-2 toxicity (20.8% vs. 25.5% respectively, p = 0.69). Similarly, excellent or good cosmetic result scores were similar in both groups (p = 0.80)

CONCLUSIONS

In our single-institution review, we observed no adverse effects of chemotherapy in combination with hypofractionated whole-breast irradiation. Further investigations are necessary to better elucidate the effects of chemotherapy on skin toxicity in the context of hypofractionated irradiation.

A review on radiotherapy hypofractionation schedules for breast cancer treatment

Radiation therapy is an integral part of management in breast carcinoma treatment. Standard curative schedules of radiotherapy to the breast deliver 25 fractions of 2.0 Gy per day over 5–6 weeks. Considerable recent literature suggests that hypo-fractionation may be advisory in breast cancer. The use of fewer fractions of more than 2 Gy per day (hypo-fractionation) is based on data suggesting that breast carcinoma is more sensitive to fraction size than squamous carcinomas and therefore could have similar fractionation sensitivity to the dose-limiting healthy tissues, including skin, subcutaneous tissues, muscle and ribs. In this article, a review of published studies and currently ongoing trials, which may provide evidence for the use of hypo-fractionated radiotherapy in breast cancer patients, is presented. Also, for all these different hypo-fractionation regimens found in literature, biologically effective dose (BED) values are calculated and compared. Data from studies and randomised trials seem to support the concept that modest hypo-fractionation can be used to treat the whole breast after breast-conserving surgery with similar rates of local control and radiation morbidity as seen with conventional fractionation.

Hypofractionated radiotherapy after conservative surgery for breast cancer: analysis of acute and late toxicity

BACKGROUND

A variety of hypofractionated radiotherapy schedules has been proposed after breast conserving surgery in the attempt to shorten the overall treatment time. The aim of the present study is to assess acute and late toxicity of using daily fractionation of 2.25 Gy to a total dose of 45 Gy to the whole breast in a mono-institutional series.

METHODS

Eighty-five women with early breast cancer were assigned to receive 45 Gy followed by a boost to the tumour bed. Early and late toxicity were scored according to the Radiation Therapy Oncology Group criteria. For comparison, a group of 70 patients with similar characteristics and treated with conventional fractionation of 2 Gy to a total dose of 50 Gy in 25 fractions followed by a boost, was retrospectively selected.

RESULTS

Overall median treatment duration was 29 days for hypofractionated radiotherapy and 37 days for conventional radiotherapy. Early reactions were observed in 72/85 (85%) patients treated with hypofractionation and in 67/70 (96%) patients treated with conventional fractionation (p = 0.01). Late toxicity was observed in 8 patients (10%) in the hypofractionation group and in 10 patients (15%) in the conventional fractionation group, respectively (p = 0.4).

CONCLUSIONS

The hypofractionated schedule delivering 45 Gy in 20 fractions shortened the overall treatment time by 1 week with a reduction of skin acute toxicity and no increase of late effects compared to the conventional fractionation. Our results support the implementation of hypofractionated schedules in clinical practice.

A biologically competitive 21 days hypofractionation scheme with weekly concomitant boost in breast cancer radiotherapy feasibility acute sub-acute and short term late effects

Background

Radiation therapy after lumpectomy is a standard part of breast conserving therapy for invasive breast carcinoma. The most frequently used schedule worldwide is 60 Gy in 30 fractions in 6 weeks, a time commitment that sporadically may dissuade some otherwise eligible women from undertaking treatment. The purpose and primary endpoint of this perspective study is to evaluate feasibility and short-term late toxicity in a hypofractionated whole breast irradiation schedule.

Methods

Between February and October 2008 we treated 65 consecutive patients with operable invasive early-stage breast cancer with a hypofractionated schedule of external beam radiation therapy. All patients were assigned to 39 Gy in 13 fractions in 3 weeks to the whole breast plus a concomitant weekly boost dose to the lumpectomy cavity of 3 Gy in 3 fractions.

Results

All the patients had achieved a median follow up of 24 months (range 21-29 months). At the end of treatment 52% presented grade 0 acute toxicity 39% had grade 1 and 9% had grade 2. At 6 months with all the patients assessed there were 34% case of grade 1 subacute toxicity and 6% of grade 2. At 12 months 43% and 3% of patients presented with clinical grade 1 and grade 2 fibrosis respectively and 5% presented grade 1 hyperpigmentation. The remaining patients were free of side effects. At 24 months, with 56 assessed, just 2 patients (3%) showed grade 2 of late fibrosis.

Conclusions

The clinical results observed showed a reasonably good feasibility of the accelerated hypofractionated schedule in terms of acute, subacute and short-term late toxicity. This useful 13 fractions with a concomitant boost schedule seems, in selected patients, a biologically acceptable alternative to the traditional 30 days regime.

Fraction size in radiation treatment for breast conservation in early breast cancer

BACKGROUND

Shortening the duration of radiation therapy would benefit women with early breast cancer treated with breast conserving surgery. It may also improve access to radiation therapy by improving efficiency in radiation oncology departments globally. This can only happen if the shorter treatment is as effective and safe as conventional radiation therapy. This is an updated version of the original Cochrane Review published in Issue 3, 2008.

OBJECTIVES

To determine the effect of altered radiation fraction size on outcomes for women with early breast cancer who have undergone breast conserving surgery.

SEARCH STRATEGY

We searched the Cochrane Breast Cancer Group Specialised Register, MEDLINE, EMBASE and the WHO ICTRP search portal to June 2009, reference lists of articles and relevant conference proceedings. We applied no language constraints.

SELECTION CRITERIA

Randomised controlled trials of unconventional versus conventional fractionation in women with early breast cancer who had undergone breast conserving surgery.

DATA COLLECTION AND ANALYSIS

The authors performed data extraction independently, with disagreements resolved by discussion. We sought missing data from trial authors.

MAIN RESULTS

Four trials reported on 7095 women. The women were highly selected: tumours were node negative and 89.8% were smaller than 3 cm. Where the breast size was known, 87% had small or medium breasts. The studies were of low to medium quality. Unconventional fractionation (delivering radiation therapy in larger amounts each day but over fewer days than with conventional fractionation) did not affect: (1) local recurrence risk ratio (RR) 0.97 (95% CI 0.76 to 1.22, P = 0.78), (2) breast appearance RR 1.17 (95% CI 0.98 to 1.39, P = 0.09), (3) survival at five years RR 0.89 (95% CI 0.77 to 1.04, P = 0.16). Acute skin toxicity was decreased with unconventional fractionation: RR 0.21 (95% CI 0.07 to 0.64, P = 0.007).

AUTHORS' CONCLUSIONS

Two new studies have been published since the last version of the review, altering our conclusions. We have evidence from four low to medium quality randomised trials that using unconventional fractionation regimens (greater than 2 Gy per fraction) does not affect local recurrence, is associated with decreased acute toxicity and does not seem to affect breast appearance or late toxicity for selected women treated with breast conserving therapy. These are mostly women with node negative tumours smaller than 3 cm and negative pathological margins. Long-term follow up (> 5 years) is available for a small proportion of the patients randomised. Longer follow up is required for a more complete assessment of the effect of altered fractionation.