To report interim cosmetic and toxicity results of a multicenter randomized trial comparing accelerated partial-breast irradiation (APBI) using three-dimensional conformal external beam radiation ...therapy (3D-CRT) with whole-breast irradiation (WBI).
Women age > 40 years with invasive or in situ breast cancer ≤ 3 cm were randomly assigned after breast-conserving surgery to 3D-CRT APBI (38.5 Gy in 10 fractions twice daily) or WBI (42.5 Gy in 16 or 50 Gy in 25 daily fractions ± boost irradiation). The primary outcome was ipsilateral breast tumor recurrence (IBTR). Secondary outcomes were cosmesis and toxicity. Adverse cosmesis was defined as a fair or poor global cosmetic score. After a planned interim cosmetic analysis, the data, safety, and monitoring committee recommended release of results. There have been too few IBTR events to trigger an efficacy analysis.
Between 2006 and 2011, 2,135 women were randomly assigned to 3D-CRT APBI or WBI. Median follow-up was 36 months. Adverse cosmesis at 3 years was increased among those treated with APBI compared with WBI as assessed by trained nurses (29% v 17%; P < .001), by patients (26% v 18%; P = .0022), and by physicians reviewing digital photographs (35% v 17%; P < .001). Grade 3 toxicities were rare in both treatment arms (1.4% v 0%), but grade 1 and 2 toxicities were increased among those who received APBI compared with WBI (P < .001).
3D-CRT APBI increased rates of adverse cosmesis and late radiation toxicity compared with standard WBI. Clinicians and patients are cautioned against the use of 3D-CRT APBI outside the context of a controlled trial.
Volumetric modulated arc therapy (VMAT) is a novel extension of conventional intensity-modulated radiotherapy (cIMRT), in which an optimized three-dimensional dose distribution may be delivered in a ...single gantry rotation. VMAT is the predecessor to RapidArc (Varian Medical System). This study compared VMAT with cIMRT and with conventional modified wide-tangent (MWT) techniques for locoregional radiotherapy for left-sided breast cancer, including internal mammary nodes.
Therapy for 5 patients previously treated with 50 Gy/25 fractions using nine-field cIMRT was replanned with VMAT and MWT. Comparative endpoints were planning target volume (PTV) dose homogeneity, doses to surrounding structures, number of monitor units, and treatment delivery time.
For VMAT, two 190 degrees arcs with 2-cm overlapping jaws were required to optimize over the large treatment volumes. Treatment plans generated using VMAT optimization resulted in PTV homogeneity similar to that of cIMRT and MWT. The average heart volumes receiving >30 Gy for VMAT, cIMRT, and MWT were 2.6% +/- 0.7%, 3.5% +/- 0.8%, and 16.4% +/- 4.3%, respectively, and the average ipsilateral lung volumes receiving >20 Gy were 16.9% +/- 1.1%, 17.3% +/- 0.9%, and 37.3% +/- 7.2%, respectively. The average mean dose to the contralateral medial breast was 3.2 +/- 0.6 Gy for VMAT, 4.3 +/- 0.4 Gy for cIMRT, and 4.4 +/- 4.7 Gy for MWT. The healthy tissue volume percentages receiving 5 Gy were significantly larger with VMAT (33.1% +/- 2.1%) and IMRT (45.3% +/- 3.1%) than with MWT (19.4% +/- 3.7%). VMAT reduced the number of monitor units by 30% and the treatment time by 55% compared with cIMRT.
VMAT achieved similar PTV coverage and sparing of organs at risk, with fewer monitor units and shorter delivery time than cIMRT.
Women with breast cancer who are undergoing breast-conserving surgery were assigned to receive whole-breast irradiation with or without regional nodal irradiation. At 10 years, disease-free survival ...in the nodal-irradiation group was improved but overall survival was not.
Many women with early-stage breast cancer undergo breast-conserving surgery followed by whole-breast irradiation, which reduces the rate of local recurrence.
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Radiotherapy to the chest wall and regional lymph nodes, termed regional nodal irradiation, which is commonly used after mastectomy in women with node-positive breast cancer who are treated with adjuvant systemic therapy, reduces locoregional and distant recurrence and improves overall survival.
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An unanswered question is whether the addition of regional nodal irradiation to whole-breast irradiation after breast-conserving surgery has the same effect. Whole-breast irradiation may involve irradiation of the lower axillary and internal mammary lymph nodes.
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However, regional . . .
Abstract Background and purpose We report the long-term outcomes in patients enrolled in a multicenter randomized controlled trial comparing Intensity Modulated Radiation Therapy (IMRT) with standard ...wedge radiotherapy. Materials and methods Trial participants were assessed to compare long-term side effects between treatment arms. The primary endpoint was chronic breast pain assessed by trained observers blinded to treatment allocation. Secondary endpoints included cosmesis and quality of life measures. Results Median follow-up time was 9.8 years and 241 patients were available for assessment. There was no significant difference in chronic pain between treatment arms (OR = 0.74, range 0.432–1.271). There were also no differences for the secondary endpoints. Univariate and multivariate analyses identified young age ( p = 0.013) and pain during RT ( p < 0.001) to be associated with chronic pain. Acute moist desquamation was associated with late subcutaneous fibrosis ( p = 0.003) and telangiectasia ( p = 0.039). Pain during RT was associated with a long-term poorer self-assessed cosmetic outcome ( p < 0.001) and quality of life ( p < 0.001). Conclusions Breast IMRT cannot be recommended for all patients to reduce long-term side effects. However, late toxicities were significantly correlated with acute side effects, which are increased in patients having poor dose distribution. Breast IMRT may hence be useful for selected patients.
To determine if time to start of adjuvant chemotherapy after curative surgery influences survival in early-stage breast cancer.
A retrospective review was conducted of 2,594 patients receiving ...adjuvant chemotherapy for stage I and II breast cancer between 1989 and 1998 at the British Columbia Cancer Agency. Relapse-free survival (RFS) and overall survival (OS) were compared among patients grouped by time from definitive curative surgery to start of adjuvant chemotherapy (< or = 4 weeks, > 4 to 8 weeks, > 8 to 12 weeks, and >12 to 24 weeks).
RFS and OS were similar for women starting chemotherapy up to 12 weeks after surgery. OS hazard ratio (univariate) for initiation of chemotherapy more than 12 weeks compared with 12 weeks or less after surgery was 1.5 (95% CI, 1.07 to 2.10; P = .017). Five-year OS rates were 84%, 85%, 89%, and 78%, (log-rank P = .013); RFS rates were 74%, 79%, 82%, and 69% (log-rank P = .004) for patients starting chemotherapy 4 weeks or fewer, more than 4 to 8 weeks, more than 8 to 12 weeks, and more than 12 to 24 weeks after surgery, respectively. In multivariate analysis, independent prognostic factors were grade, size, nodal status, estrogen receptor, age, and lymphatic and/or vascular invasion. Initiation of adjuvant chemotherapy more than 12 weeks from surgery remained significantly associated with inferior survival, with a hazard ratio of 1.6 (95% CI, 1.2 to 2.3; P = .005).
This retrospective analysis suggests that adjuvant chemotherapy is equally effective up to 12 weeks after definitive surgery but that RFS and OS appear to be compromised by delays of more than 12 weeks after definitive surgery.
Human epidermal growth factor receptor 2 gene (HER2) is associated with a poorer outcome in node-positive breast cancer, but the results are conflicting in node-negative disease. This study assessed ...the prognostic impact of HER2 overexpression/amplification in a large series of node-negative breast cancers.
A tissue microarray (TMA) series was constructed consisting of 4,444 invasive breast cancers diagnosed in British Columbia from 1986 to 1992. Within this series, 2,026 patients were node negative, of whom 70% did not receive adjuvant systemic therapy. The TMA series was assessed for estrogen receptor (ER) and HER2. Logistic regression modeling was used to estimate odds ratios at the 10-year follow-up.
HER2 was positive in 10.2% of the node-negative cohort. In this cohort, an inferior outcome was seen in patients with HER2-positive tumors compared with HER2-negative tumors for 10-year relapse-free survival (RFS; 65.9% v 75.5%, respectively; P = .01), distant RFS (71.2% v 81.8%, respectively; P = .004), and breast cancer-specific survival (BCSS; 75.5% v 86.3%, respectively; P = .001). A trend for a worse overall survival was also seen (P = .06). HER2 was an independent poor prognostic factor for RFS and BCSS at 10 years, with odds ratios of 1.71 (P = .01) and 2.03 (P = .003), respectively. The number of HER2-positive tumors that were <or= 1 cm was small, but there was a trend for a worse outcome in T1b tumors.
HER2 overexpression/amplification is correlated with a poorer outcome in node-negative breast cancer. Larger studies are needed to more clearly define the prognostic impact of HER2 in tumors <or= 1 cm, particularly within the separate hormone receptor subgroups.
Whole breast irradiation (WBI) after conservative surgery for ductal carcinoma in situ (DCIS) reduces local recurrence. We investigated whether a tumour bed boost after WBI improved outcomes, and ...examined radiation dose fractionation sensitivity for non-low-risk DCIS.
The study was an international, randomised, unmasked, phase 3 trial involving 136 participating centres of six clinical trials organisations in 11 countries (Australia, New Zealand, Singapore, Canada, the Netherlands, Belgium, France, Switzerland, Italy, Ireland, and the UK). Eligible patients were women aged 18 years or older with unilateral, histologically proven, non-low-risk DCIS treated by breast-conserving surgery with at least 1 mm of clear radial resection margins. They were assigned to one of four groups (1:1:1:1) of no tumour bed boost versus boost after conventional versus hypofractionated WBI, or randomly assigned to one of two groups (1:1) of no boost versus boost after each centre prespecified conventional or hypofractionated WBI. The conventional WBI used was 50 Gy in 25 fractions, and hypofractionated WBI was 42·5 Gy in 16 fractions. A boost dose of 16 Gy in eight fractions, if allocated, was delivered after WBI. Patients and clinicians were not masked to treatment allocation. The primary endpoint was time to local recurrence. This trial is registered with ClinicalTrials.gov (NCT00470236).
Between June 25, 2007, and June 30, 2014, 1608 patients were randomly assigned to have no boost (805 patients) or boost (803 patients). Conventional WBI was given to 831 patients, and hypofractionated WBI was given to 777 patients. Median follow-up was 6·6 years. The 5-year free-from-local-recurrence rates were 92·7% (95% CI 90·6–94·4%) in the no-boost group and 97·1% (95·6–98·1%) in the boost group (hazard ratio 0·47; 0·31–0·72; p<0·001). The boost group had higher rates of grade 2 or higher breast pain (10% 8–12% vs 14% 12–17%, p=0·003) and induration (6% 5–8% vs 14% 11–16%, p<0·001).
In patients with resected non-low-risk DCIS, a tumour bed boost after WBI reduced local recurrence with an increase in grade 2 or greater toxicity. The results provide the first randomised trial data to support the use of boost radiation after postoperative WBI in these patients to improve local control. The international scale of the study supports the generalisability of the results.
National Health and Medical Research Council of Australia, Susan G Komen for the Cure, Breast Cancer Now, OncoSuisse, Dutch Cancer Society, Canadian Cancer Trials Group.
Adjuvant! (www.adjuvantonline.com) is a web-based tool that predicts 10-year breast cancer outcomes with and without adjuvant systemic therapy, but it has not been independently validated.
Using the ...British Columbia Breast Cancer Outcomes Unit (BCOU) database, demographic, pathologic, staging, and treatment data on 4,083 women diagnosed between 1989 and 1993 in British Columbia with T1-2, N0-1, M0 breast cancer were abstracted and entered into Adjuvant! to calculate predicted 10-year overall survival (OS), breast cancer-specific survival (BCSS), and event-free survival (EFS) for each patient. Individual BCOU observed outcomes at 10 years were independently determined. Predicted and observed outcomes were compared.
Across all 4,083 patients, 10-year predicted and observed outcomes were within 1% for OS, BCSS, and EFS (all P > .05). Predicted and observed outcomes were within 2% for most demographic, pathologic, and treatment-defined subgroups. Adjuvant! overestimated OS, BCSS, and EFS in women younger than age 35 years (predicted-observed = 8.6%, 9.6%, and 13.6%, respectively; all P < .001) or with lymphatic or vascular invasion (LVI; predicted-observed = 3.6%, 3.8%, and 4.2%, respectively; all P < .05); these two prognostic factors were not automatically incorporated within the Adjuvant! algorithm. After adjusting for the distribution of LVI, using the prognostic factor impact calculator in Adjuvant!, 10-year predicted and observed outcomes were no longer significantly different.
Adjuvant! performed reliably. Patients younger than age 35 or with known additional adverse prognostic factors such as LVI require adjustment of risks to derive reliable predictions of prognosis without adjuvant systemic therapy and the absolute benefits of adjuvant systemic therapy.
This study investigated the cosmetic degradation and toxicity for an accelerated partial breast irradiation (APBI) prescription delivered in 5 fractions over 1 week and compared the outcomes with ...those of whole breast irradiation (WBI).
The trial was a multicenter, single-arm, phase 2 prospective cohort study. Eligible women 50 years of age or older with estrogen receptor–positive and human epidermal growth factor receptor 2–negative invasive ductal carcinoma or ductal carcinoma in situ after breast-conserving surgery received 27 Gy in 5 daily fractions of APBI. The primary endpoint was noninferiority of 2-year cosmesis using the RAPID trial's WBI arm as the control arm. A global consensus cosmetic score using a European Organisation for Research and Treatment of Cancer rating scale score of excellent, good, fair, or poor for each patient at baseline and 2 years was generated by a panel of 5 radiation oncologists using photographs of treated and untreated breasts.
From 2016 to 2019, 298 eligible women were enrolled. By the 2-year follow-up, 76 patients had been lost or withdrawn and 3 had died, resulting in 219 patients available for complete, 2-year photographic cosmetic evaluation. The median follow-up for all participants was 4.7 years (IQR, 3.8-5.5 years). No patient had a fair or poor cosmetic score at the 2-year evaluation. Cosmesis was better or unchanged for 97% of patients and worse for 3% (excellent to good), and no cosmetic failures occurred. The confidence intervals were 0.88 (0.86-0.90) and 1.00 (0.99-1.00) for the RAPID and ACCEL trials, respectively.
Cosmetic degradation with 5 daily treatments of the ACCEL trial's APBI intervention is noninferior to the WBI arm of the RAPID trial.