Saskia Litière

Doxorubicin alone versus intensified doxorubicin plus ifosfamide for first-line treatment of advanced or metastatic soft-tissue sarcoma: a randomised controlled phase 3 trial

BACKGROUND Effective targeted treatment is unavailable for most sarcomas and doxorubicin and ifosfamide-which have been used to treat soft-tissue sarcoma for more than 30 years-still have an important role. Whether doxorubicin alone or the combination of doxorubicin and ifosfamide should be used routinely is still controversial. We assessed whether dose intensification of doxorubicin with ifosfamide improves survival of patients with advanced soft-tissue sarcoma compared with doxorubicin alone. METHODS We did this phase 3 randomised controlled trial (EORTC 62012) at 38 hospitals in ten countries. We included patients with locally advanced, unresectable, or metastatic high-grade soft-tissue sarcoma, age 18-60 years with a WHO performance status of 0 or 1. They were randomly assigned (1:1) by the minimisation method to either doxorubicin (75 mg/m(2) by intravenous bolus on day 1 or 72 h continuous intravenous infusion) or intensified doxorubicin (75 mg/m(2); 25 mg/m(2) per day, days 1-3) plus ifosfamide (10 g/m(2) over 4 days with mesna and pegfilgrastim) as first-line treatment. Randomisation was stratified by centre, performance status (0 vs 1), age (<50 vs ≥50 years), presence of liver metastases, and histopathological grade (2 vs 3). Patients were treated every 3 weeks till progression or unacceptable toxic effects for up to six cycles. The primary endpoint was overall survival in the intention-to-treat population. The trial is registered with ClinicalTrials.gov, number NCT00061984. FINDINGS Between April 30, 2003, and May 25, 2010, 228 patients were randomly assigned to receive doxorubicin and 227 to receive doxorubicin and ifosfamide. Median follow-up was 56 months (IQR 31-77) in the doxorubicin only group and 59 months (36-72) in the combination group. There was no significant difference in overall survival between groups (median overall survival 12·8 months [95·5% CI 10·5-14·3] in the doxorubicin group vs 14·3 months [12·5-16·5] in the doxorubicin and ifosfamide group; hazard ratio [HR] 0·83 [95·5% CI 0·67-1·03]; stratified log-rank test p=0·076). Median progression-free survival was significantly higher for the doxorubicin and ifosfamide group (7·4 months [95% CI 6·6-8·3]) than for the doxorubicin group (4·6 months [2·9-5·6]; HR 0·74 [95% CI 0·60-0·90], stratified log-rank test p=0·003). More patients in the doxorubicin and ifosfamide group than in the doxorubicin group had an overall response (60 [26%] of 227 patients vs 31 [14%] of 228; p<0·0006). The most common grade 3 and 4 toxic effects-which were all more common with doxorubicin and ifosfamide than with doxorubicin alone-were leucopenia (97 [43%] of 224 patients vs 40 [18%] of 223 patients), neutropenia (93 [42%] vs 83 [37%]), febrile neutropenia (103 (46%) vs 30 [13%]), anaemia (78 [35%] vs 10 [5%]), and thrombocytopenia (75 [33%]) vs one [<1%]). INTERPRETATION Our results do not support the use of intensified doxorubicin and ifosfamide for palliation of advanced soft-tissue sarcoma unless the specific goal is tumour shrinkage. These findings should help individualise the care of patients with this disease. FUNDING Cancer Research UK, EORTC Charitable Trust, UK NHS, Canadian Cancer Society Research Institute, Amgen.

Soft tissue and visceral sarcomas: ESMO–EURACAN Clinical Practice Guidelines for diagnosis, treatment and follow-up

Fondazione IRCCS Istituto Nazionale dei Tumori and University of Milan, Milan, Italy; Instituto Portugues de Oncologia de Lisboa Francisco Gentil, EPE, Lisbon, Portugal; University Hospital Essen, Essen, Germany; Department of Oncological Orthopedics, Musculoskeletal Tissue Bank, IFO, Regina Elena National Cancer Institute, Rome, Italy; Klinikum Stuttgart-Olgahospital, Stuttgart, Germany; Institut Curie, Paris, France; NORDIX, Athens, Greece; Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands; Vienna General Hospital (AKH), Medizinische Universität Wien, Vienna, Austria; Hospital Universitario Virgen del Rocio-CIBERONC, Seville, Spain; Centro di Riferimento Oncologico di Aviano, Aviano; Ospedale Regionale di Treviso “S.Maria di Cà Foncello”, Treviso, Italy; Integrated Unit ICO Hospitalet, HUB, Barcelona, Spain; Sarcoma Unit, University College London Hospitals, London, UK; Skane University Hospital-Lund, Lund, Sweden; N. N. Blokhin Russian Cancer Research Center, Moscow, Russian Federation; Institute of Scientific Hospital Care (IRCCS), Regina Elena National Cancer Institute, Rome; Pediatric Oncology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan; Istituto Ortopedico Rizzoli, Bologna; Azienda Ospedaliera Universitaria Careggi Firenze, Florence, Italy; Department of Medical Oncology, Leiden University Medical Centre, Leiden, The Netherlands; Institut Jules Bordet, Brussels, Belgium; Candiolo Cancer Institute, FPO IRCCS, Candiolo, Italy; Department of Radiotherapy, The Netherlands Cancer Institute, Amsterdam and Department of Radiotherapy, Leiden University Medical Centre, Leiden, The Netherlands; Turku University Hospital (Turun Yliopistollinen Keskussairaala), Turlu, Finland; Oxford University Hospitals NHS Foundation Trust, Oxford, UK; Mannheim University Medical Center, Mannheim; Department of Medicine III, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany; Helsinki University Central Hospital (HUCH), Helsinki, Finland; Royal Marsden Hospital, London; The Institute of Cancer Research, London, UK; University Medical Center Groningen, Groningen; Radboud University Medical Center, Nijmegen, The Netherlands; University Hospital Motol, Prague; Masaryk Memorial Cancer Institute, Brno, Czech Republic; Gustave Roussy Cancer Campus, Villejuif, France; Maria Skłodowska Curie Institute, Oncology Centre, Warsaw, Poland; Tel Aviv Sourasky Medical Center (Ichilov), Tel Aviv, Israel; Medical Oncology, University Hospital of Lausanne, Lausanne, Switzerland; Azienda Ospedaliera, Universitaria, Policlinico S Orsola-Malpighi Università di Bologna, Bologna; Azienda Ospedaliero, Universitaria Cita della Salute e della Scienza di Torino, Turin, Italy; Fundacio de Gestio Sanitaria de L’hospital de la SANTA CREU I Sant Pau, Barcelona, Spain; Helios Klinikum Berlin Buch, Berlin, Germany; YCRC Department of Clinical Oncology, Weston Park Hospital NHS Trust, Sheffield, UK; Aarhus University Hospital, Aarhus, Finland; Leuven Cancer Institute, Leuven, Belgium; Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands; Fondazione Istituto di Ricovero e Cura a Carattere Scientifico, Istituto Nazionale dei Tumori, Milan, Italy; Department of Oncology, Oslo University Hospital, The Norwegian Radium Hospital, Oslo, Norway; Institute of Oncology of Ljubljana, Ljubljana, Slovenia; Netherlands Cancer Institute Antoni van Leeuwenhoek, Amsterdam, The Netherlands; University College Hospital, London, UK; Gerhard-Domagk-Institut für Pathologie, Universitätsklinikum Münster, Münster, Germany; Oslo University Hospital, Norwegian Radium Hospital, Oslo, Norway; Centre Leon Bernard and UCBL1, Lyon, France

Breast conserving therapy versus mastectomy for stage I-II breast cancer: 20 year follow-up of the EORTC 10801 phase 3 randomised trial

BACKGROUND The EORTC 10801 trial compared breast-conserving therapy (BCT) with modified radical mastectomy (MRM) in patients with tumours 5 cm or smaller and axillary node negative or positive disease. Compared with BCT, MRM resulted in better local control, but did not affect overall survival or time to distant metastases. We report 20-year follow-up results. METHODS The EORTC 10801 trial was open for accrual between 1980 and 1986 in eight centres in the UK, the Netherlands, Belgium, and South Africa. 448 patients were randomised to BCT and 420 to MRM. Randomisation was done centrally, stratifying patients by institute, carcinoma stage (I or II), and menopausal status. BCT comprised of lumpectomy and complete axillary clearance, followed by breast radiotherapy and a tumour-bed boost. The primary endpoint was time to distant metastasis. This analysis was done on all eligible patients, as they were randomised. FINDINGS After a median follow-up of 22·1 years (IQR 18·5-23·8), 175 patients (42%) had distant metastases in the MRM group versus 207 (46%) in the BCT group. Furthermore, 506 patients (58%) died (232 [55%] in the MRM group and 274 [61%] in the BCT group). No significant difference was observed between BCT and MRM for time to distant metastases (hazard ratio 1·13, 95% CI 0·92-1·38; p=0·23) or for time to death (1·11, 0·94-1·33; 0·23). Cumulative incidence of distant metastases at 20 years was 42·6% (95% CI 37·8-47·5) in the MRM group and 46·9% (42·2-51·6) in the BCT group. 20-year overall survival was estimated to be 44·5% (95% CI 39·3-49·5) in the MRM group and 39·1% (34·4-43·9) in the BCT group. There was no difference between the groups in time to distant metastases or overall survival by age (time to distant metastases: <50 years 1·09 [95% CI 0·79-1·51] vs ≥50 years 1·16 [0·90-1·50]; overall survival <50 years 1·17 [0·86-1·59] vs ≥50 years 1·10 [0·89-1·37]). INTERPRETATION BCT, including radiotherapy, offered as standard care to patients with early breast cancer seems to be justified, since long-term follow-up in this trial showed similar survival to that after mastectomy. FUNDING European Organisation for Research and Treatment of Cancer (EORTC).

Breast-Conserving Treatment With or Without Radiotherapy in Ductal Carcinoma In Situ: 15-Year Recurrence Rates and Outcome After a Recurrence, From the EORTC 10853 Randomized Phase III Trial

PURPOSE Adjuvant radiotherapy (RT) after a local excision (LE) for ductal carcinoma in situ (DCIS) aims at reduction of the incidence of a local recurrence (LR). We analyzed the long-term risk on developing LR and its impact on survival after local treatment for DCIS. PATIENTS AND METHODS Between 1986 and 1996, 1,010 women with complete LE of DCIS less than 5 cm were randomly assigned to no further treatment (LE group, n = 503) or RT (LE+RT group, n = 507). The median follow-up time was 15.8 years. RESULTS Radiotherapy reduced the risk of any LR by 48% (hazard ratio [HR], 0.52; 95% CI, 0.40 to 0.68; P < .001). The 15-year LR-free rate was 69% in the LE group, which was increased to 82% in the LE+RT group. The 15-year invasive LR-free rate was 84% in the LE group and 90% in the LE+RT group (HR, 0.61; 95% CI, 0.42 to 0.87). The differences in LR in both arms did not lead to differences in breast cancer-specific survival (BCSS; HR, 1.07; 95% CI, 0.60 to 1.91) or overall survival (OS; HR, 1.02; 95% CI, 0.71 to 1.44). Patients with invasive LR had a significantly worse BCSS (HR, 17.66; 95% CI, 8.86 to 35.18) and OS (HR, 5.17; 95% CI, 3.09 to 8.66) compared with those who did not experience recurrence. A lower overall salvage mastectomy rate after LR was observed in the LE+RT group than in the LE group (13% v 19%, respectively). CONCLUSION At 15 years, almost one in three nonirradiated women developed an LR after LE for DCIS. RT reduced this risk by a factor of 2. Although women who developed an invasive recurrence had worse survival, the long-term prognosis was good and independent of the given treatment.

iRECIST: guidelines for response criteria for use in trials testing immunotherapeutics

Tumours respond differently to immunotherapies compared with chemotherapeutic drugs, raising questions about the assessment of changes in tumour burden-a mainstay of evaluation of cancer therapeutics that provides key information about objective response and disease progression. A consensus guideline-iRECIST-was developed by the RECIST working group for the use of modified Response Evaluation Criteria in Solid Tumours (RECIST version 1.1) in cancer immunotherapy trials, to ensure consistent design and data collection, facilitate the ongoing collection of trial data, and ultimate validation of the guideline. This guideline describes a standard approach to solid tumour measurements and definitions for objective change in tumour size for use in trials in which an immunotherapy is used. Additionally, it defines the minimum datapoints required from future trials and those currently in development to facilitate the compilation of a data warehouse to use to later validate iRECIST. An unprecedented number of trials have been done, initiated, or are planned to test new immune modulators for cancer therapy using a variety of modified response criteria. This guideline will allow consistent conduct, interpretation, and analysis of trials of immunotherapies.

TP53 status for prediction of sensitivity to taxane versus non-taxane neoadjuvant chemotherapy in breast cancer (EORTC 10994/BIG 1-00): a randomised phase 3 trial

BACKGROUND TP53 has a crucial role in the DNA damage response. We therefore tested the hypothesis that taxanes confer a greater advantage than do anthracyclines on breast cancers with mutated TP53 than in those with wild-type TP53. METHODS In an open-label, phase 3 study, women (age <71 years) with locally advanced, inflammatory, or large operable breast cancers were randomly assigned in a 1:1 ratio to either a standard anthracycline regimen (six cycles of intravenous fluorouracil 500 mg/m², epirubicin 100 mg/m², and cyclophosphamide 500 mg/m² every 21 days [FEC100], or fluorouracil 600 mg/m², epirubicin 75 mg/m², cyclophosphamide 900 mg/m² [tailored FEC] starting on day 1 and then every 21 days) or a taxane-based regimen (three cycles of docetaxel 100 mg/m², intravenously infused over 1 h on day 1 every 21 days, followed by three cycles of intravenous epirubicin 90 mg/m² and docetaxel 75 mg/m² on day 1 every 21 days [T-ET]) at 42 centres in Europe. Randomisation was by use of a minimisation method that stratified patients by institution and initial tumour stage. The primary endpoint was progression-free survival (PFS) according to TP53 status. Analysis was by intention to treat. This is the final analysis of this trial. The study is registered with ClinicalTrials.gov, number NCT00017095. FINDINGS 928 patients were enrolled in the FEC group and 928 in the T-ET group. TP53 status was not assessable for 183 (20%) patients in the FEC group and 204 (22%) patients in the T-ET group mainly because of low tumour-cell content in the biopsy. 361 primary endpoint events were recorded in the FEC group and 314 in the T-ET group. In patients with TP53-mutated tumours, 5-year PFS was 59·5% (95% CI 53·4-65·1) in the T-ET group (n=326) and 55·3% (49·2-60·9) in the FEC group (n=318; hazard ratio 0·84, 98% CI 0·63-1·14; p=0·17). In patients with TP53 wild-type tumours, 5-year PFS was 66·8% (95% CI 61·4-71·6) in the T-ET group (n=398) and 64·7% (59·6-69·4) in the FEC group (n=427; 0·89, 98% CI 0·68-1·18; p=0·35). For all patients, irrespective of TP53 status, 5-year PFS was 65·1% (95% CI 61·6-68·3) in the T-ET group and 60·8% (57·3-64·2) in the FEC group (0·85, 98% CI 0·71-1·02; p=0·035). At the sites using FEC100 versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (75 [9%] of 803 vs 173 [21%] of 809, respectively), and neutropenia (653 [81%] vs 730 [90%], respectively). At the sites using tailored FEC versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (ten [8%] of 118 vs 26 [22%] of 116, respectively), and neutropenia (100 [85%] vs 115 [99%], respectively). Two patients died of toxicity during or within 30 days of chemotherapy completion and without disease relapse (one in each group). INTERPRETATION Although TP53 status was prognostic for overall survival, it was not predictive of preferential sensitivity to taxanes. TP53 status tested by use of the yeast assay in this patient population cannot be used to select patients for an anthracycline-based chemotherapy versus a taxane-based chemotherapy. FUNDING US National Cancer Institute, La Ligue Nationale Contre le Cancer, European Union, Pharmacia, and Sanofi-Aventis.

Doxorubicin-based adjuvant chemotherapy in soft tissue sarcoma: pooled analysis of two STBSG-EORTC phase III clinical trials

BACKGROUND The EORTC-STBSG coordinated two large trials of adjuvant chemotherapy (CT) in localized high-grade soft tissue sarcoma (STS). Both studies failed to demonstrate any benefit on overall survival (OS). The aim of the analysis of these two trials was to identify subgroups of patients who may benefit from adjuvant CT. PATIENTS AND METHODS Individual patient data from two EORTC trials comparing doxorubicin-based CT to observation only in completely resected STS (large resection, R0/marginal resection, R1) were pooled. Prognostic factors were assessed by univariate and multivariate analyses. Patient outcomes were subsequently compared between the two groups of patients according to each analyzed factor. RESULTS A total of 819 patients had been enrolled with a median follow-up of 8.2 years. Tumor size, high histological grade and R1 resection emerged as independent adverse prognostic factors for relapse-free survival (RFS) and OS. Adjuvant CT is an independent favorable prognostic factor for RFS but not for OS. A significant interaction between benefit of adjuvant CT and age, gender and R1 resection was observed for RFS and OS. Males and patients >40 years had a significantly better RFS in the treatment arms, while adjuvant CT was associated with a marginally worse OS in females and patients <40 years. Patients with R1 resection had a significantly better RFS and OS favoring adjuvant CT arms. CONCLUSION Adjuvant CT is not associated with a better OS in young patients or in any pathology subgroup. Poor quality of initial surgery is the most important prognostic and predictive factor for utility of adjuvant CT in STS. Based on these data, we conclude that adjuvant CT for STS remains an investigational procedure and is not a routine standard of care.

Pathological complete response after neoadjuvant chemotherapy is an independent predictive factor irrespective of simplified breast cancer intrinsic subtypes: a landmark and two-step approach analyses from the EORTC 10994/BIG 1-00 phase III trial

BACKGROUND Pathological complete response (pCR) following chemotherapy is strongly associated with both breast cancer subtype and long-term survival. Within a phase III neoadjuvant chemotherapy trial, we sought to determine whether the prognostic implications of pCR, TP53 status and treatment arm (taxane versus non-taxane) differed between intrinsic subtypes. PATIENTS AND METHODS Patients were randomized to receive either six cycles of anthracycline-based chemotherapy or three cycles of docetaxel then three cycles of eprirubicin/docetaxel (T-ET). pCR was defined as no evidence of residual invasive cancer (or very few scattered tumour cells) in primary tumour and lymph nodes. We used a simplified intrinsic subtypes classification, as suggested by the 2011 St Gallen consensus. Interactions between pCR, TP53 status, treatment arm and intrinsic subtype on event-free survival (EFS), distant metastasis-free survival (DMFS) and overall survival (OS) were studied using a landmark and a two-step approach multivariate analyses. RESULTS Sufficient data for pCR analyses were available in 1212 (65%) of 1856 patients randomized. pCR occurred in 222 of 1212 (18%) patients: 37 of 496 (7.5%) luminal A, 22 of 147 (15%) luminal B/HER2 negative, 51 of 230 (22%) luminal B/HER2 positive, 43 of 118 (36%) HER2 positive/non-luminal, 69 of 221(31%) triple negative (TN). The prognostic effect of pCR on EFS did not differ between subtypes and was an independent predictor for better EFS [hazard ratio (HR) = 0.40, P < 0.001 in favour of pCR], DMFS (HR = 0.32, P < 0.001) and OS (HR = 0.32, P < 0.001). Chemotherapy arm was an independent predictor only for EFS (HR = 0.73, P = 0.004 in favour of T-ET). The interaction between TP53, intrinsic subtypes and survival outcomes only approached statistical significance for EFS (P = 0.1). CONCLUSIONS pCR is an independent predictor of favourable clinical outcomes in all molecular subtypes in a two-step multivariate analysis. CLINICALTRIALSGOV EORTC 10994/BIG 1-00 Trial registration number NCT00017095.

Long-term responders and survivors on pazopanib for advanced soft tissue sarcomas: subanalysis of two European Organisation for Research and Treatment of Cancer (EORTC) clinical trials 62043 and 62072.

BACKGROUND Pazopanib recently received approval for the treatment of certain soft tissue sarcoma (STS) subtypes. We conducted a retrospective analysis on pooled data from two EORTC trials on pazopanib in STS in order to characterize long-term responders and survivors. PATIENTS AND METHODS Selected patients were treated with pazopanib in phase II (n = 118) and phase III study (PALETTE) (n = 226). Combined median progression-free survival (PFS) was 4.4 months; the median overall survival (OS) was 11.7 months. Thirty-six percent of patients had a PFS ≥ 6 months and were defined as long-term responders; 34% of patients survived ≥18 months, defined as long-term survivors. Patient characteristics were studied for their association with long-term outcomes. RESULTS The median follow-up was 2.3 years. Patient characteristics were compared among four subgroups based on short-/long-term PFS and OS, respectively. Seventy-six patients (22.1%) were both long-term responders and long-term survivors. The analysis confirmed the importance of known prognostic factors in metastatic STS patients treated with systemic treatment, such as performance status and tumor grading, and additionally hemoglobin at baseline as new prognostic factor. We identified 12 patients (3.5%) remaining on pazopanib for more than 2 years: nine aged younger than 50 years, nine females, four with smooth muscle tumors and nine with low or intermediate grade tumors at initial diagnosis. The median time on pazopanib in these patients was 2.4 years with the longest duration of 3.7 years. CONCLUSIONS Thirty-six percent and 34% of all STS patients who received pazopanib in these studies had a long PFS and/or OS, respectively. For more than 2 years, 3.5% of patients remained progression free under pazopanib. Good performance status, low/intermediate grade of the primary tumor and a normal hemoglobin level at baseline were advantageous for long-term outcome. NCT00297258 (phase II) and NCT00753688 (phase III, PALETTE).BACKGROUND Pazopanib recently received approval for the treatment of certain soft tissue sarcoma (STS) subtypes. We conducted a retrospective analysis on pooled data from two EORTC trials on pazopanib in STS in order to characterize long-term responders and survivors. PATIENTS AND METHODS Selected patients were treated with pazopanib in phase II (n = 118) and phase III study (PALETTE) (n = 226). Combined median progression-free survival (PFS) was 4.4 months; the median overall survival (OS) was 11.7 months. Thirty-six percent of patients had a PFS ≥ 6 months and were defined as long-term responders; 34% of patients survived ≥18 months, defined as long-term survivors. Patient characteristics were studied for their association with long-term outcomes. RESULTS The median follow-up was 2.3 years. Patient characteristics were compared among four subgroups based on short-/long-term PFS and OS, respectively. Seventy-six patients (22.1%) were both long-term responders and long-term survivors. The analysis confirmed the importance of known prognostic factors in metastatic STS patients treated with systemic treatment, such as performance status and tumor grading, and additionally hemoglobin at baseline as new prognostic factor. We identified 12 patients (3.5%) remaining on pazopanib for more than 2 years: nine aged younger than 50 years, nine females, four with smooth muscle tumors and nine with low or intermediate grade tumors at initial diagnosis. The median time on pazopanib in these patients was 2.4 years with the longest duration of 3.7 years. CONCLUSIONS Thirty-six percent and 34% of all STS patients who received pazopanib in these studies had a long PFS and/or OS, respectively. For more than 2 years, 3.5% of patients remained progression free under pazopanib. Good performance status, low/intermediate grade of the primary tumor and a normal hemoglobin level at baseline were advantageous for long-term outcome. NCT00297258 (phase II) and NCT00753688 (phase III, PALETTE).

Comparison of the sentinel node procedure between patients with multifocal and unifocal breast cancer in the EORTC 10981-22023 AMAROS Trial: Identification rate and nodal outcome

INTRODUCTION Multifocal breast cancer is associated with a higher risk of nodal involvement compared to unifocal breast cancer and the drainage pattern from multifocal localisations may be different. For this reason, the value of the sentinel node biopsy (SNB) procedure for this indication is debated. The aim of the current analysis was to evaluate the sentinel node identification rate and nodal involvement in patients with a multifocal tumour in the EORTC 10981-22023 AMAROS trial. PATIENTS AND METHODS From the first 4000 registered patients, 342 were identified with a multifocal tumour on histological examination and compared to a randomly selected control group of 684 patients with a unifocal tumour. The outcome of the SNB was assessed. RESULTS The sentinel node was identified in 96% of the patients with a multifocal tumour and in 98% of those with unifocal disease. In the multifocal group, 51% had a metastasis in the sentinel node compared to 28% in the unifocal group; and further nodal involvement after a positive sentinel node was found in 40% (38/95) and 39% (39/101) respectively. CONCLUSION In this prospective international multicentre study, the 96% detection rate indicates that the SNB procedure can be highly effective in patients with a multifocal tumour. Though the tumour-positive rate of the sentinel node was twice as high in the multifocal group compared to the unifocal group, further nodal involvement after a positive sentinel node was similar in both groups. This suggests that the SNB procedure is safe in patients with multifocal breast cancer.