BACKGROUND:Several randomised, phase 3 trials have investigated the value of different techniques of accelerated partial breast irradiation (APBI) for patients with early breast cancer after breast-conserving surgery compared with whole-breast irradiation. In a phase 3 randomised trial, we evaluated whether APBI using multicatheter brachytherapy is non-inferior compared with whole-breast irradiation. Here, we present the 10-year follow-up results. METHODS:We did a randomised, phase 3, non-inferiority trial at 16 hospitals and medical centres in Austria, Czech Republic, Germany, Hungary, Poland, Spain, and Switzerland. Patients aged 40 years or older with early invasive breast cancer or ductal carcinoma in situ treated with breast-conserving surgery were centrally randomly assigned (1:1) to receive either whole-breast irradiation or APBI using multicatheter brachytherapy. Whole-breast irradiation was delivered in 25 daily fractions of 50 Gy over 5 weeks, with a supplemental boost of 10 Gy to the tumour bed, and APBI was delivered as 30·1 Gy (seven fractions) and 32·0 Gy (eight fractions) of high-dose-rate brachytherapy in 5 days or as 50 Gy of pulsed-dose-rate brachytherapy over 5 treatment days. Neither patients nor investigators were masked to treatment allocation. The primary endpoint was ipsilateral local recurrence, analysed in the as-treated population; the non-inferiority margin for the recurrence rate difference (defined for 5-year results) was 3 percentage points. The trial is registered with ClinicalTrials.gov, NCT00402519; the trial is complete. FINDINGS:Between April 20, 2004, and July 30, 2009, 1328 female patients were randomly assigned to whole breast irradiation (n=673) or APBI (n=655), of whom 551 in the whole-breast irradiation group and 633 in the APBI group were eligible for analysis. At a median follow-up of 10·36 years (IQR 9·12-11·28), the 10-year local recurrence rates were 1·58% (95% CI 0·37 to 2·8) in the whole-breast irradiation group and 3·51% (1·99 to 5·03) in the APBI group. The difference in 10-year rates between the groups was 1·93% (95% CI -0·018 to 3·87; p=0·074). Adverse events were mostly grade 1 and 2, in 234 (60%) of 393 participants in the whole-breast irradiation group and 314 (67%) of 470 participants in the APBI group, at 7·5-year or 10-year follow-up, or both. Patients in the APBI group had a significantly lower incidence of treatment-related grade 3 late side-effects than those in the whole-breast irradiation group (17 [4%] of 393 for whole-breast irradiation vs seven [1%] of 470 for APBI; p=0·021; at 7·5-year or 10-year follow-up, or both). At 10 years, the most common type of grade 3 adverse event in both treatment groups was fibrosis (six [2%] of 313 patients for whole-breast irradiation and three [1%] of 375 patients for APBI, p=0·56). No grade 4 adverse events or treatment-related deaths have been observed. INTERPRETATION:Postoperative APBI using multicatheter brachytherapy after breast-conserving surgery in patients with early breast cancer is a valuable alternative to whole-breast irradiation in terms of treatment efficacy and is associated with fewer late side-effects. FUNDING:German Cancer Aid, Germany.

AbstractCarcinoma erysipelatoides (CE) is a rare clinical manifestation of cutaneous metastasis, which mimics inflammatory conditions such as erysipelas. Depending on the site of the originating tumour, unusual manifestations involving different sites of the body may occur. We herein report a case of a 60‐year‐old female patient with metastatic endometrial carcinoma presenting as CE of the abdominal skin and the inguinal folds. Even though the diagnosis of advanced malignancy had been established before and she was currently receiving chemotherapy (carboplatin and paclitaxel), the clinical appearance closely resembled fungal (candidal intertrigo) and consecutively bacterial (erysipelas) infection, which resulted in treatment with antimycotics and antibiotics at first. Dermatohistopathological examination of skin biopsies revealed a diffuse and nodular infiltrate of pleomorphic atypical tumour cells with strong expression of cytokeratin 7 and PAX8, also detectable within lymphatic vessels. Therapy comprised antiseptic ointments to prevent superinfection, palliative electron beam radiation and supportive care. Since there were no targetable KRAS‐, NRAS‐ and BRAF‐gene mutations, systemic therapy was switched to checkpoint inhibition (pembrolizumab) in combination with lenvatinib. The overall prognosis of cutaneous metastasis of endometrial carcinoma is dismal with most patients succumbing to disease within few months. Similarly, our patient died after 3 months due to sepsis in the course of malignant pleural effusion. We aim to highlight the possibility of unusual sites of CE and the risk of respective clinical misdiagnoses.

Importance Total neoadjuvant therapy has been increasingly adopted for multimodal rectal cancer treatment. The optimal sequence of chemoradiotherapy (CRT) and chemotherapy needs to be established. Objective To report the long-term results of the secondary end points prespecified in the Randomized Phase 2 Trial of Chemoradiotherapy Plus Induction or Consolidation Chemotherapy as Total Neoadjuvant Therapy (CAO/ARO/AIO-12 trial) for Locally Advanced Rectal Cancer. Design, Setting, and Participants This secondary analysis of a randomized clinical trial included 311 patients who were recruited from the accrued CAO/ARO/AIO-12 trial population from June 15, 2015, to January 31, 2018, from 18 centers in Germany. Patients with cT3-4 and/or node-positive rectal adenocarcinoma were included in the analysis. Data were analyzed from June 15, 2015, to January 31, 2018. The follow-up analysis was conducted between January 31, 2018, and November 30, 2020. Interventions Patients were randomly assigned to group A for 3 cycles of fluorouracil, leucovorin, and oxaliplatin before fluorouracil/oxaliplatin CRT (50.4 Gy), or to group B for CRT before chemotherapy. Total mesorectal excision was scheduled on day 123 after the start of total neoadjuvant therapy in both groups. Main Outcomes and Measures The end points assessed in this secondary analysis included long-term oncologic outcomes, chronic toxicity, patient-reported outcome measures for global health status (GHS) and quality of life (QoL), and the Wexner stool incontinence score. Results Of the 311 patients enrolled, 306 were evaluable, including 156 in group A (mean [SD] age, 60 [11] years; 106 men [68%]) and 150 in group B (mean [SD] age, 62 [10] years; 100 men [67%]). After a median follow-up of 43 months (range, 35-60 months), the 3-year disease-free survival was 73% in both groups (hazard ratio, 0.95; 95% CI, 0.63-1.45, P = .82); the 3-year cumulative incidence of locoregional recurrence (6% vs 5%, P = .67) and distant metastases (18% vs 16%, P = .52) were not significantly different. Chronic toxicity grade 3 to 4 occurred in 10 of 85 patients (11.8%) in group A and 8 of 66 patients (9.9%) in group B at 3 years. The GHS/QoL score decreased after total mesorectal excision but returned to pretreatment levels 1 year after randomization with no difference between the groups. Stool incontinence deteriorated 1 year after randomization in both groups and only improved slightly at 3 years, but never reached baseline levels. Conclusions and Relevance This secondary analysis of a randomized clinical trial showed that CRT followed by chemotherapy resulted in higher pathological complete response without compromising disease-free survival, toxicity, QoL, or stool incontinence and is thus proposed as the preferred total neoadjuvant therapy sequence if organ preservation is a priority. Trial Registration ClinicalTrials.gov identifier: NCT02363374.

BACKGROUND:Large variation regarding prescription and dose inhomogeneity exists in stereotactic body radiation therapy (SBRT) for early-stage non-small cell lung cancer. The aim of this modeling study was to identify which dose metric correlates best with local tumor control probability to make recommendations regarding SBRT prescription. METHODS AND MATERIALS:We combined 2 retrospective databases of patients with non-small cell lung cancer, yielding 1500 SBRT treatments for analysis. Three dose parameters were converted to biologically effective doses (BEDs): (1) the (near-minimum) dose prescribed to the planning target volume (PTV) periphery (yielding BEDmin); (2) the (near-maximum) dose absorbed by 1% of the PTV (yielding BEDmax); and (3) the average between near-minimum and near-maximum doses (yielding BEDave). These BED parameters were then correlated to the risk of local recurrence through Cox regression. Furthermore, BED-based prediction of local recurrence was attempted by logistic regression and fast and frugal trees. Models were compared using the Akaike information criterion. RESULTS:There were 1500 treatments in 1434 patients; 117 tumors recurred locally. Actuarial local control rates at 12 and 36 months were 96.8% (95% confidence interval, 95.8%-97.8%) and 89.0% (87.0%-91.1%), respectively. In univariable Cox regression, BEDave was the best predictor of risk of local recurrence, and a model based on BEDmin had substantially less evidential support. In univariable logistic regression, the model based on BEDave also performed best. Multivariable classification using fast and frugal trees revealed BEDmax to be the most important predictor, followed by BEDave. CONCLUSIONS:BEDave was generally better correlated with tumor control probability than either BEDmax or BEDmin. Because the average between near-minimum and near-maximum doses was highly correlated to the mean gross tumor volume dose, the latter may be used as a prescription target. More emphasis could be placed on achieving sufficiently high mean doses within the gross tumor volume rather than the PTV covering dose, a concept needing further validation.

PURPOSE Total neoadjuvant therapy is a new paradigm for rectal cancer treatment. Optimal scheduling of preoperative chemoradiotherapy (CRT) and chemotherapy remains to be established. PATIENTS AND METHODS We conducted a multicenter, randomized, phase II trial using a pick-the-winner design on the basis of the hypothesis of an increased pathologic complete response (pCR) of 25% after total neoadjuvant therapy compared with standard 15% after preoperative CRT. Patients with stage II or III rectal cancer were assigned to group A for induction chemotherapy using three cycles of fluorouracil, leucovorin, and oxaliplatin before fluorouracil/oxaliplatin CRT (50.4 Gy) or to group B for consolidation chemotherapy after CRT. Secondary end points included toxicity, compliance, and surgical morbidity. RESULTS Of the 311 patients enrolled, 306 patients were evaluable (156 in group A and 150 in group B). CRT-related grade 3 or 4 toxicity was lower (37% v 27%) and compliance with CRT higher in group B (91%, 78%, and 76% v 97%, 87%, and 93% received full-dose radiotherapy, concomitant fluorouracil, and concomitant oxaliplatin in groups A and B, respectively); 92% versus 85% completed all induction/consolidation chemotherapy cycles, respectively. The longer interval between completion of CRT and surgery in group B (median 90 v 45 days in group A) did not increase surgical morbidity. A pCR in the intention-to-treat population was achieved in 17% in group A and in 25% in group B. Thus, only group B (P < .001), but not group A (P = .210), fulfilled the predefined statistical hypothesis. CONCLUSION Up-front CRT followed by chemotherapy resulted in better compliance with CRT but worse compliance with chemotherapy compared with group A. Long-term follow-up will assess whether improved pCR in group B translates to better oncologic outcome.

BACKGROUND:High-dose hypofractionated radiotherapy should theoretically result in a deviation from the typical linear-quadratic shape of the cell survival curve beyond a certain threshold dose, yet no evidence for this hypothesis has so far been found in clinical data of stereotactic body radiotherapy treatment (SBRT) for early-stage non-small cell lung cancer (NSCLC). A pragmatic explanation is a larger α/β ratio than the conventionally assumed 10 Gy. We here attempted an estimation of the α/β ratio for NSCLC treated with SBRT using individual patient data. MATERIALS AND METHODS:We combined two large retrospective datasets, yielding 1294 SBRTs (≤10 fractions) of early stage NSCLC. Cox proportional hazards regression, a logistic tumor control probability model and a biologically motivated Bayesian cure rate model were used to estimate the α/β ratio based on the observed number of local recurrences and accounting for tumor size. RESULTS:A total of 109 local progressions were observed after a median of 17.7 months (range 0.6-76.3 months). Cox regression, logistic regression of 3 year tumor control probability and the cure rate model yielded best-fit estimates of α/β = 12.8 Gy, 14.9 Gy and 12-16 Gy (depending on the prior for α/β), respectively, although with large uncertainties that did not rule out the conventional α/β = 10 Gy. CONCLUSIONS:Clinicians can continue to use the simple LQ formalism to compare different SBRT treatment schedules for NSCLC. While α/β = 10 Gy is not ruled out by our data, larger values in the range 12-16 Gy are more probable, consistent with recent meta-regression analyses.

BackgroundNon-small cell lung cancer (NSCLC) with mediastinal lymph node involvement (N2) is a heterogeneous entity. The objective of this analysis is to investigate the results of treatment strategies for N2-positive patients.MethodsRetrospective study (2009-2014) of 104 consecutive patients with stage IIIA-N2 NSCLC classified according to the Robinson classification (IIIA1-IIIA4) and treated within a multimodality treatment regime.ResultsThe Robinson subgroups were: IIIA1 (n=27), IIIA3 (n=60) and IIIA4 (n=17). We had no stage IIIA2 samples because we did not perform an intraoperative frozen section of lymph nodes. Surgical resection with systematic lymph node dissection was performed in all patients with stage IIIA1 (n=27). After chemotherapy or chemo-/radiotherapy, 53.3% of patients in stage IIIA3 (n=32) and 11.7% of patients in stage IIIA4 (n=2) underwent surgery with curative intention. R0 was achieved in 92.6% in stage IIIA1, 93.8% in stage IIIA3 and 100% in stage IIIA4. The 30-day mortality was 3.2%. The overall median survival was 31.7 months (5-year survival was 30.5%). There were no significant differences (P=0.583) in survival regarding the Robinson subgroups. Patients who underwent tumour resection had significantly better median survival (39.8 vs. 19.6 months; P=0.014) compared to patients treated conservatively. Deviation from the interdisciplinary recommended therapy (12%) led to a reduced median survival (11.4 vs. 31.8 months; P=0.137).ConclusionsN2-patients should be subclassified according to the Robinson classification and discussed in the tumour board. Surgical resection should be recommended in specific cases of N2-disease (non-bulky, sensitivity to systemic treatment).

BackgroundPrevious results from the GEC-ESTRO trial showed that accelerated partial breast irradiation (APBI) using multicatheter brachytherapy in the treatment of early breast cancer after breast-conserving surgery was non-inferior to whole-breast irradiation in terms of local control and overall survival. Here, we present 5-year results of patient-reported quality of life.MethodsWe did this randomised controlled phase 3 trial at 16 hospitals and medical centres in seven European countries. Patients aged 40 years or older with 0–IIA breast cancer were randomly assigned (1:1) after breast-conserving surgery (resection margins ≥2 mm) to receive either whole-breast irradiation of 50 Gy with a boost of 10 Gy or APBI using multicatheter brachytherapy. Randomisation was stratified by study centre, tumour type, and menopausal status, with a block size of ten and an automated dynamic algorithm. There was no masking …

Background Previous results from the GEC-ESTRO trial showed that accelerated partial breast irradiation (APBI) using multicatheter brachytherapy in the treatment of early breast cancer after breast-conserving surgery was noninferior to whole-breast irradiation in terms of local control and overall survival. Here, we present 5-year results of patient-reported quality of life. Methods We did this randomised controlled phase 3 trial at 16 hospitals and medical centres in seven European countries. Patients aged 40 years or older with 0-IIA breast cancer were randomly assigned (1:1) after breast-conserving surgery (resection margins >= 2 mm) to receive either whole-breast irradiation of 50 Gy with a boost of 10 Gy or APBI using multicatheter brachytherapy. Randomisation was stratified by study centre, tumour type, and menopausal status, with a block size of ten and an automated dynamic algorithm. There was no masking of patients or investigators. The primary endpoint of the trial was ipsilateral local recurrence. Here, we present 5-year results of quality of life (a prespecified secondary endpoint). Quality-of-life questionnaires (European Organisation for Research and Treatment of Cancer QLQ-C30, breast cancer module QLQ-BR23) were completed before radiotherapy (baseline 1), immediately after radiotherapy (baseline 2), and during follow-up. We analysed the data according to treatment received (as-treated population). Recruitment was completed in 2009, and long-term follow-up is continuing. The trial is registered at ClinicalTrials. gov, number NCT00402519. Findings Between April 20, 2004, and July 30, 2009, 633 patients had accelerated partial breast irradiation and 551 patients had whole-breast irradiation. Quality-of-life questionnaires at baseline 1 were available for 334 (53%) of 663 patients in the APBI group and 314 (57%) of 551 patients in the whole-breast irradiation group; the response rate was similar during follow-up.Global health status (range 0-100) was stable in both groups: at baseline 1, APBI group mean score 65.5 (SD 20.6) versus whole-breast irradiation group 64.6 (19.6), p=0.37; at 5 years, APBI group 66.2 (22.2) versus whole-breast irradiation group 66.0 (21.8), p=0.94.The only moderate, significant difference (difference of 10-20 points) between the groups was found in the breast symptoms scale.Breast symptom scores were significantly higher (ie, worse) after whole-breast irradiation than after APBI at baseline 2 (difference of means 13.6, 95% CI 9.7-17.5; p<0.0001) and at 3-month follow-up (difference of means 12.7, 95% CI 9.8-15.6; p<0.0001). Interpretation APBI with multicatheter brachytherapy was not associated with worse quality of life compared with whole-breast irradiation.This finding supports APBI as an alternative treatment option after breast-conserving surgery for patients with early breast cancer. Copyright (c) 2018 Elsevier Ltd.All rights reserved.

BACKGROUND:We previously confirmed the non-inferiority of accelerated partial breast irradiation (APBI) with interstitial brachytherapy in terms of local control and overall survival compared with whole-breast irradiation for patients with early-stage breast cancer who underwent breast-conserving surgery in a phase 3 randomised trial. Here, we present the 5-year late side-effects and cosmetic results of the trial. METHODS:We did this randomised, controlled, phase 3 trial at 16 centres in seven European countries. Women aged 40 years or older with stage 0-IIA breast cancer who underwent breast-conserving surgery with microscopically clear resection margins of at least 2 mm were randomly assigned 1:1, via an online interface, to receive either whole-breast irradiation of 50 Gy with a tumour-bed boost of 10 Gy or APBI with interstitial brachytherapy. Randomisation was stratified by study centre, menopausal status, and tumour type (invasive carcinoma vs ductal carcinoma in situ), with a block size of ten, according to an automated dynamic algorithm. Patients and investigators were not masked to treatment allocation. The primary endpoint of our initial analysis was ipsilateral local recurrence; here, we report the secondary endpoints of late side-effects and cosmesis. We analysed physician-scored late toxicities and patient-scored and physician-scored cosmetic results from the date of breast-conserving surgery to the date of onset of event. Analysis was done according to treatment received (as-treated population). This trial is registered with ClinicalTrials.gov, number NCT00402519. FINDINGS:Between April 20, 2004, and July 30, 2009, we randomly assigned 1328 women to receive either whole-breast irradiation (n=673) or APBI with interstitial brachytherapy (n=655); 1184 patients comprised the as-treated population (551 in the whole-breast irradiation group and 633 in the APBI group). At a median follow-up of 6·6 years (IQR 5·8-7·6), no patients had any grade 4 toxities, and three (<1%) of 484 patients in the APBI group and seven (2%) of 393 in the whole-breast irradiation group had grade 3 late skin toxicity (p=0·16). No patients in the APBI group and two (<1%) in the whole-breast irradiation group developed grade 3 late subcutaneous tissue toxicity (p=0·10). The cumulative incidence of any late side-effect of grade 2 or worse at 5 years was 27·0% (95% CI 23·0-30·9) in the whole-breast irradiation group versus 23·3% (19·9-26·8) in the APBI group (p=0·12). The cumulative incidence of grade 2-3 late skin toxicity at 5 years was 10·7% (95% CI 8·0-13·4) in the whole-breast irradiation group versus 6·9% (4·8-9·0) in the APBI group (difference -3·8%, 95% CI -7·2 to 0·4; p=0·020). The cumulative risk of grade 2-3 late subcutaneous tissue side-effects at 5 years was 9·7% (95% CI 7·1-12·3) in the whole-breast irradiation group versus 12·0% (9·4-14·7) in the APBI group (difference 2·4%; 95% CI -1·4 to 6·1; p=0·28). The cumulative incidence of grade 2-3 breast pain was 11·9% (95% CI 9·0-14·7) after whole-breast irradiation versus 8·4% (6·1-10·6) after APBI (difference -3·5%; 95% CI -7·1 to 0·1; p=0·074). At 5 years' follow-up, according to the patients' view, 413 (91%) of 454 patients had excellent to good cosmetic results in the whole-breast irradiation group versus 498 (92%) of 541 patients in the APBI group (p=0·62); when judged by the physicians, 408 (90%) of 454 patients and 503 (93%) of 542 patients, respectively, had excellent to good cosmetic results (p=0·12). No treatment-related deaths occurred, but six (15%) of 41 patients (three in each group) died from breast cancer, and 35 (85%) deaths (21 in the whole-breast irradiation group and 14 in the APBI group) were unrelated. INTERPRETATION:5-year toxicity profiles and cosmetic results were similar in patients treated with breast-conserving surgery followed by either APBI with interstitial brachytherapy or conventional whole-breast irradiation, with significantly fewer grade 2-3 late skin side-effects after APBI with interstitial brachytherapy. These findings provide further clinical evidence for the routine use of interstitial multicatheter brachytherapy-based APBI in the treatment of patients with low-risk breast cancer who opt for breast conservation. FUNDING:German Cancer Aid.

Background and purposeTo compare early side effects and patient compliance of accelerated partial breast irradiation (APBI) with multicatheter brachytherapy to external beam whole breast irradiation (WBI) in a low-risk group of patients with breast cancer.Material and methodsBetween April 2004 and July 2009, 1328 patients with UICC stage 0–IIA breast cancer were randomized to receive WBI with 50Gy and a boost of 10Gy or APBI with either 32.0Gy/8 fractions, or 30.1Gy/7 fractions (HDR-brachytherapy), or 50Gy/0.60–0.80Gy per pulse (PDR-brachytherapy). This report focuses on early side-effects and patient compliance observed in 1186 analyzable patients. ClinicalTrials.gov identifier: NCT00402519.ResultsPatient compliance was excellent in both arms. Both WBI and APBI were well tolerated with moderate early side-effects. No grade 4 toxicity had been observed. Grade 3 side effects were exclusively seen for early skin toxicity (radiation dermatitis) with 7% vs. 0.2% (p<0.0001), and breast infection with 0% vs. 0.2% (p=n.s.) for patients treated with WBI and APBI. The incidence of grades 1–2 early side effects for WBI and APBI was 86% vs. 21% (p<0.0001) for skin toxicity, 2% vs. 20% (p<0.0001) for mild hematoma, and 2% vs. 5% (p=0.01) for mild breast infection rates, respectively. No differences had been found regarding grades 1–2 early breast pain (26% vs. 29%, p=0.23).ConclusionsAPBI with interstitial multicatheter brachytherapy was tolerated very well and dramatically reduced early skin toxicity in comparison to standard WBI.

To evaluate efficacy results of the GEC-ESTRO phase III non-inferiority trial in subgroups of patients defined by the ASTRO and GEC-ESTRO criteria for patient selection for APBI. Patients aged ≥40 years with low risk invasive breast cancer and ductal carcinoma in-situ after BCS were randomized to receive either 50 Gy WBI with tumor bed boost of 10 Gy or APBI using multicatheter brachytherapy. 633/1083 patients were randomized to APBI using multicatheter brachytherapy. We report a sub-analysis of these latter 633 patients regarding 5-year local control rates, disease-free and overall survival results comparing subgroups categorized according to ASTRO and GEC-ESTRO criteria for patient selection for APBI. The trial is registered with ClinicalTrials.gov, NCT00402519. Among 633 patients treated with sole multicatheter brachytherapy for APBI, 430 patients (68%) were classified according to GEC-ESTRO criteria as good candidates for APBI - "low risk group", 203 (32%) as possible candidates for APBI - "intermediate risk group" and no patient was in the "high risk group". According to ASTRO criteria, 247 patients (39%) classified as "suitable", 287 (45%) as "cautionary" and 98 (16%) as "unsuitable". Using ESTRO criteria for subgrouping of patients, the cumulative incidence of local recurrence at 5 years was 1.18% versus 2% (p=0.42) in the "low risk group" and "intermediate risk group", respectively. Furthermore 5-year disease-free survival was 94.6% versus 96% (p = 0.49) and 5-year overall survival was 96.7% versus 98.5% (p = 0.25) in the "low risk group" and "intermediate risk group", respectively. Using ASTRO criteria for subgrouping of patients, the cumulative incidence of local recurrence at 5 years was 2.04%, 1.05% and 1.05% in the "suitable", "cautionary" and "unsuitable" groups (p=0.6), respectively. 5-year disease-free survival was 94.3%, 95.1% and 96.8% in the "suitable", "cautionary" and "unsuitable" groups (p=0.63), respectively. 5-year overall survival was 96.7%, 97.2% and 99.0% in the "suitable", "cautionary" and "unsuitable" groups (p = 0.53), respectively. However, it should be pointed out that due to the hitherto low number of events, statistical power and precision, respectively, to identify differences between subgroups is limited. The 5-year results are similar in patients treated with breast conserving surgery followed by APBI using multicatheter brachytherapy in "low risk group" and "intermediate risk group" according to GEC-ESTRO criteria and in all risk groups' according to ASTRO criteria. As a consequence, we believe that in due time, a careful revision of current ASTRO and ESTRO selection criteria for APBI should be discussed.

The 5-year survival results of the GEC-ESTRO APBI trial have been reported recently. In this analysis we report the 5-year incidences of late toxicities and cosmetic results of patients treated with APBI using multi-catheter brachytherapy (BT) compared to those who underwent whole breast irradiation (WBI). Between 2004 and 2009, 1184 eligible patients aged ≥40 years with stage 0-IIA breast cancer who underwent breast conserving surgery (BCS) were randomly assigned to receive either 50 Gy WBI with tumor bed boost of 10 Gy or APBI using HDR/PDR multi-catheter BT. Among these, 5-year follow-up records (with a time window between 4 and 6 years) on late toxicities and cosmetic results were available for 942 patients (80%). Five-year incidences of late toxicities scored by the RTOG/EORTC scheme were compared using Fisher’s exact test. Five-year rates of skin and soft tissue toxicities were estimated in terms of cumulative incidences. Cosmetic results were scored by both patients and treating radiation oncologists before RT and annually thereafter. The prevalence of grade (G) 2-3 late skin toxicity at 5 years was 3.7% in the APBI group vs. 6.1% in the WBI group (p=0.06). The 5-year rate of ≥G2 skin toxicity was 6.71% (95%CI: 4.67-8.75%) after APBI, and 10.5% (95%CI: 7.78-13.1%) after WBI. The frequency of any (G1-3) skin pigmentation was 5.7% vs. 10.0%, respectively (p=0.009). The 5-year rate of ≥G2 skin pigmentation was 2.94% (95%CI: 1.60-4.28%) after APBI, and 7.33% (95%CI: 5.08-9.57%) after WBI. Concerning G2-3 late subcutaneous tissue side effects, the prevalence was 6.2% in the APBI group vs. 5.4% in the WBI group (p=0.33). The 5-year rate of ≥G2 soft tissue toxicity was 11.4% (95%CI: 8.82-14.0%) after APBI, and 9.60% (95%CI: 7.01-12.2%) after WBI. The respective frequency of symptomatic fat necrosis was 1.2% vs. 0.9% (p=0.49). Neither APBI nor WBI deteriorated baseline cosmetic appearance over time. The prevalence of G2-3 breast pain was low in both arms (0.6% after APBI; 1.6% after WBI; p=0.11).The rate of excellent/good cosmetic results judged by the patients was 92.2% vs. 91.1% (p=0.57) in the APBI and WBI group, and 92.7% vs. 90.0% (p=0.14) scored by the physicians. However, more patients experienced excellent cosmetic results after APBI compared to WBI either rated by the patients (43.6% vs. 30.9%; p=0.00002) or the physicians (39.7% vs. 30.7%; p<0.002). The 5-year toxicity profile and cosmetic results are similar in patients treated with BCS followed by either APBI using multi-catheter BT or WBI. Significantly less late skin side effects and a trend towards better cosmetic results have been observed in the APBI arm.

BACKGROUND:In a phase 3, randomised, non-inferiority trial, accelerated partial breast irradiation (APBI) for patients with stage 0, I, and IIA breast cancer who underwent breast-conserving treatment was compared with whole-breast irradiation. Here, we present 5-year follow-up results.METHODS:We did a phase 3, randomised, non-inferiority trial at 16 hospitals and medical centres in seven European countries. 1184 patients with low-risk invasive and ductal carcinoma in situ treated with breast-conserving surgery were centrally randomised to either whole-breast irradiation or APBI using multicatheter brachytherapy. The primary endpoint was local recurrence. Analysis was done according to treatment received. This trial is registered with ClinicalTrials.gov, number NCT00402519.FINDINGS:Between April 20, 2004, and July 30, 2009, 551 patients had whole-breast irradiation with tumour-bed boost and 633 patients received APBI using interstitial multicatheter brachytherapy. At 5-year follow-up, nine patients treated with APBI and five patients receiving whole-breast irradiation had a local recurrence; the cumulative incidence of local recurrence was 1.44% (95% CI 0.51-2.38) with APBI and 0.92% (0.12-1.73) with whole-breast irradiation (difference 0.52%, 95% CI -0.72 to 1.75; p=0.42). No grade 4 late side-effects were reported. The 5-year risk of grade 2-3 late side-effects to the skin was 3.2% with APBI versus 5.7% with whole-breast irradiation (p=0.08), and 5-year risk of grade 2-3 subcutaneous tissue late side-effects was 7.6% versus 6.3% (p=0.53). The risk of severe (grade 3) fibrosis at 5 years was 0.2% with whole-breast irradiation and 0% with APBI (p=0.46).INTERPRETATION:The difference between treatments was below the relevance margin of 3 percentage points. Therefore, adjuvant APBI using multicatheter brachytherapy after breast-conserving surgery in patients with early breast cancer is not inferior to adjuvant whole-breast irradiation with respect to 5-year local control, disease-free survival, and overall survival.FUNDING:German Cancer Aid.

PURPOSE:Most radiobiological models for prediction of tumor control probability (TCP) do not account for the fact that many events could remain unobserved because of censoring. We therefore evaluated a set of TCP models that take into account this censoring. METHODS AND MATERIALS:We applied 2 fundamental Bayesian cure rate models to a sample of 770 pulmonary metastasis treated with stereotactic body radiation therapy at German, Austrian, and Swiss institutions: (1) the model developed by Chen, Ibrahim and Sinha (the CIS99 model); and (2) a mixture model similar to the classic model of Berkson and Gage (the BG model). In the CIS99 model the number of clonogens surviving the radiation treatment follows a Poisson distribution, whereas in the BG model only 1 dominant recurrence-competent tissue mass may remain. The dose delivered to the isocenter, tumor size and location, sex, age, and pretreatment chemotherapy were used as covariates for regression. RESULTS:Mean follow-up time was 15.5 months (range: 0.1-125). Tumor recurrence occurred in 11.6% of the metastases. Delivered dose, female sex, peripheral tumor location and having received no chemotherapy before RT were associated with higher TCP in all models. Parameter estimates of the CIS99 were consistent with the classical Cox proportional hazards model. The dose required to achieve 90% tumor control after 15.5 months was 146 (range: 114-188) Gy10 in the CIS99 and 133 (range: 101-164) Gy10 in the BG model; however, the BG model predicted lower tumor control at long (≳20 months) follow-up times and gave a suboptimal fit to the data compared to the CIS99 model. CONCLUSIONS:Biologically motivated cure rate models allow adding the time component into TCP modeling without being restricted to the follow-up period which is the case for the Cox model. In practice, application of such models to the clinical setting could allow for adaption of treatment doses depending on whether local control should be achieved in the short or longer term.

Background: Several prognostic factors for local tumor control probability (TCP) after stereotactic body radiation therapy (SBRT) for early stage non-small cell lung cancer (NSCLC) have been described, but no attempts have been undertaken to explore whether a nonlinear combination of potential factors might synergistically improve the prediction of local control.Methods and Materials: We investigated a support vector machine (SVM) for predicting TCP in a cohort of 399 patients treated at 13 German and Austrian institutions. Among 7 potential input features for the SVM we selected those most important on the basis of forward feature selection, thereby evaluating classifier performance by using 10-fold cross-validation and computing the area under the ROC curve (AUC). The final SVM classifier was built by repeating the feature selection 10 times with different splitting of the data for cross-validation and finally choosing only those features that were selected at least 5 out of 10 times. It was compared with a multivariate logistic model that was built by forward feature selection.Results: Local failure occurred in 12% of patients. Biologically effective dose (BED) at the isocenter (BEDISO) was the strongest predictor of TCP in the logistic model and also the most frequently selected input feature for the SVM. A bivariate logistic function of BEDISO and the pulmonary function indicator forced expiratory volume in 1 second (FEV1) yielded the best description of the data but resulted in a significantly smaller AUC than the final SVM classifier with the input features BEDISO, age, baseline Karnofsky index, and FEV1 (0.696 +/- 0.040 vs 0.789 +/- 0.001, P < .03). The final SVM resulted in sensitivity and specificity of 67.0% +/- 0.5% and 78.7% +/- 0.3%, respectively.Conclusions: These results confirm that machine learning techniques like SVMs can be successfully applied to predict treatment outcome after SBRT. Improvements over traditional TCP modeling are expected through a nonlinear combination of multiple features, eventually helping in the task of personalized treatment planning. (C) 2014 Elsevier Inc.

The purpose of this work is to analyze patterns of care and outcome after stereotactic body radiotherapy (SBRT) for centrally located, early-stage, non-small cell lung cancer (NSCLC) and to address the question of potential risk for increased toxicity in this entity.