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AIMS: Radiotherapy target volumes in early breast cancer treatment increasingly include the internal mammary chain (IMC). In order to maximise survival benefits of IMC radiotherapy, doses to the heart and lung should be minimised. This dosimetry study compared the ability of three-dimensional conformal radiotherapy, arc therapy and proton beam therapy (PBT) techniques with and without breath-hold to achieve target volume constraints while minimising dose to organs at risk (OARs). MATERIALS AND METHODS: In 14 patients' datasets, seven IMC radiotherapy techniques were compared: wide tangent (WT) three-dimensional conformal radiotherapy, volumetric-modulated arc therapy (VMAT) and PBT, each in voluntary deep inspiratory breath-hold (vDIBH) and free breathing (FB), and tomotherapy in FB only. Target volume coverage and OAR doses were measured for each technique. These were compared using a one-way ANOVA with all pairwise comparisons tested using Bonferroni's multiple comparisons test, with adjusted P-values ≤ 0.05 indicating statistical significance. RESULTS: One hundred per cent of WT(vDIBH), 43% of WT(FB), 100% of VMAT(vDIBH), 86% of VMAT(FB), 100% of tomotherapy FB and 100% of PBT plans in vDIBH and FB passed all mandatory constraints. However, coverage of the IMC with 90% of the prescribed dose was significantly better than all other techniques using VMAT(vDIBH), PBT(vDIBH) and PBT(FB) (mean IMC coverage ± 1 standard deviation = 96.0% ± 4.3, 99.8% ± 0.3 and 99.0% ± 0.2, respectively). The mean heart dose was significantly reduced in vDIBH compared with FB for both the WT (P < 0.0001) and VMAT (P < 0.0001) techniques. There was no advantage in target volume coverage or OAR doses for PBT(vDIBH) compared with PBT(FB). CONCLUSIONS: Simple WT radiotherapy delivered in vDIBH achieves satisfactory coverage of the IMC while meeting heart and lung dose constraints. However, where higher isodose coverage is required, VMAT(vDIBH) is the optimal photon technique. The lowest OAR doses are achieved by PBT, in which the use of vDIBH does not improve dose statistics.

We reject the inference of a “survival benefit” for patients receiving partial breast irradiation (PBI) within the IMPORT LOW trial and caution against any such interpretation when the number of events reported is so small1. There is no suggestion of a difference in disease-free and overall survival across IMPORT LOW treatment groups. The TARGIT trialist’s claim of survival benefit in their own trial relates to non-breast cancer deaths and the data cited are from a selected subset of patients. In IMPORT LOW, there were 9 cardiac deaths occurring 6-36 months following randomisation, 4 after left- and 5 after right-sided breast cancer, so no suggestion of an early radiation induced effect. Lung cancer laterality in relation to the treated breast was similar for ipsilateral and contralateral tumours, with 18/19 cases developing within 5 years of randomisation. These data fail to support an increase in radiation-induced second cancers after whole breast irradiation (WBI). Therefore, the TARGIT trialist’s suggestion that WBI causes inferior survival at 5-years’ follow-up due to either cause appears unsubstantiated.

In The Lancet, Vratislav Strnad and colleagues present 5-year results of a large, international, randomised trial testing standard whole-breast radiotherapy against accelerated partial breast irradiation (APBI) after breast-conserving surgery, in a selected low-risk population of women. The APBI technique entailed a 4–5-day postoperative course of radiotherapy delivered via radioactive sources inserted into breast tissue surrounding the operation site, the so-called tumour bed. The study design tested for non-inferiority with a primary endpoint of local recurrence in 1184 patients recruited from 16 centres, and 5-year local recurrence was less than 2% in both arms. A predefined 3% non-inferiority margin was upheld by a difference in local relapse rates of 0·52% (95% CI −0·72 to 1·75) in favour of whole-breast irradiation. There were no statistical differences in disease-free or overall survival, and adverse effects were similarly mild in both groups.

PRIMETIME is funded by Cancer Research UK (Grant number: C17918/A20015). C.E. Coles is supported by the Cambridge National Institute of Health Research Biomedical Research Centre. C.C. Kirwan is supported by a National Institute of Health Research Clinician Scientist Award (​NIHR-CS-011014).

AIMS: Breast radiotherapy-associated toxicity is often reported using clinical and photographic assessments. The addition of patient-reported outcome measures (PROMs) is becoming more common. This study investigated the concordance between clinician- and patient-reported outcomes. MATERIALS AND METHODS: The Cambridge Breast Intensity-modulated Radiotherapy (IMRT) trial prospectively collected data on clinician assessment and PROMs at 2 and 5 years after breast radiotherapy. Clinician assessment included physical examination and photographic assessment. PROMs included European Organization for Research and Treatment of Cancer (EORTC) BR23 questionnaire and four breast radiotherapy-specific questions. The correlation between patient and clinician scores were analysed on an independent patient basis using percentage agreement, Cohen's kappa coefficient (k) and Bowker's test of symmetry. The analysis was repeated after stratifying patients based on age, baseline Hospital Anxiety and Depression Score (HADS) and baseline body image score. RESULTS: At 2 and 5 years, a weak level of concordance was seen between the clinician-based assessment and PROMS for all the five toxicity end points (k = 0.05-0.21), with individual patient-based agreement of 32.9-78.3% and a highly discordant Bowker's test of symmetry (P < 0.001). The most frequently reported moderate-severe toxicity by patients was change in breast appearance (14% at both 2 and 5 years), whereas it was breast induration (36% and 25% at 2 and 5 years, respectively) by the clinicians. The lack of concordance was not affected by patient's age, baseline HADS and baseline body image score. CONCLUSIONS: This study found that moderate-severe toxicity reported by patients is low and the overall concordance between clinicians and patients is low. This could be due to methodological limitations or alternatively reflects the subjective nature of PROMs. Incorporation of a patient's perception on treatment-related toxicity will have important implications for treatment decisions and follow-up care.

In The Lancet, Vratislav Strnad and colleagues present 5-year results of a large, international, randomised trial testing standard whole-breast radiotherapy against accelerated partial breast irradiation (APBI) after breast-conserving surgery, in a selected low-risk population of women. The APBI technique entailed a 4–5-day postoperative course of radiotherapy delivered via radioactive sources inserted into breast tissue surrounding the operation site, the so-called tumour bed. The study design tested for non-inferiority with a primary endpoint of local recurrence in 1184 patients recruited from 16 centres, and 5-year local recurrence was less than 2% in both arms. A predefined 3% non-inferiority margin was upheld by a difference in local relapse rates of 0·52% (95% CI −0·72 to 1·75) in favour of whole-breast irradiation. There were no statistical differences in disease-free or overall survival, and adverse effects were similarly mild in both groups.

Objectives: To evaluate the long term outcome of CT-based image-guided brachytherapy (IGBT) for cervix cancer using the tandem-ring applicator. Methods: Between February 2005 and December 2008, 40 patients were treated with chemo-radiotherapy and high dose rate CT-based IGBT. A manually optimized dosimetry plan was created for each fraction. The planning aims were to deliver a point A dose ≥ 74 Gy10, D90 of the high-risk clinical target volume (HR-CTV) ≥ 74 Gy10, V100 HR-CTV ≥ 95%, D2cc rectum/sigmoid ≤ 75 Gy3 and D2cc bladder ≤ 95 Gy3. Results: Median follow-up was 61 months. The 3-year and 5-year cancer-specific survival was 80% (tumors 2-5 cm=87%, >5 cm=59%) and 74% (tumors 2-5 cm=87%, >5 cm=52%). The 3-year and 5-year local control was 89% (tumors 2-5 cm=96%, >5 cm=76%). The mean D90 for patients with and without local recurrence was 70.8 Gy10 and 85.2 Gy10 respectively. The 3-year and 5-year rate of G3 complications was 10% and 15%. Manual optimization could not improve the dosimetry in 96 (85%) fractions. Conclusions: CT-based IGBT improves local control compared to conventional BT, particularly for small tumors.