Effect of preoperative injection of superparamagnetic iron oxide particles on rates of sentinel lymph node dissection in women undergoing surgery for ductal carcinoma in situ (SentiNot study).

BACKGROUND: One-fifth of patients with a preoperative diagnosis of ductal carcinoma in situ (DCIS) have invasive breast cancer (IBC) on definitive histology. Sentinel lymph node dissection (SLND) is performed in almost half of women having surgery for DCIS in Sweden. The aim of the present study was to try to minimize unnecessary SLND by injecting superparamagnetic iron oxide (SPIO) nanoparticles at the time of primary breast surgery, enabling SLND to be performed later, if IBC is found in the primary specimen. METHODS: Women with DCIS at high risk for the presence of invasion undergoing breast conservation, and patients with DCIS undergoing mastectomy were included. The primary outcome was whether this technique could reduce SLND. Secondary outcomes were number of SLNDs avoided, detection rate and procedure-related costs. RESULTS: This was a preplanned interim analysis of 189 procedures. IBC was found in 47 and a secondary SLND was performed in 41 women. Thus, 78·3 per cent of patients avoided SLND (P < 0·001). At reoperation, SPIO plus blue dye outperformed isotope and blue dye in detection of the sentinel node (40 of 40 versus 26 of 40 women; P < 0·001). Costs were reduced by a mean of 24·5 per cent in women without IBC (€3990 versus 5286; P < 0·001). CONCLUSION: Marking the sentinel node with SPIO in women having surgery for DCIS was effective at avoiding unnecessary SLND in this study. Registration number: ISRCTN18430240 (http://www.isrctn.com).

Survival and risk of breast cancer recurrence after breast reconstruction with deep inferior epigastric perforator flap.

BACKGROUND: Women who undergo autologous breast reconstruction have been reported to have an increased risk of breast cancer recurrence compared with those who have mastectomy alone. It has been suggested that more extensive surgery possibly activates dormant micrometastases. The aim of this study was to evaluate whether delayed unilateral deep inferior epigastric perforator (DIEP) flap reconstruction after mastectomy increases the risk of breast cancer recurrence or affects mortality among women previously treated for breast cancer. METHODS: This was a matched retrospective cohort study including women with a previous unilateral invasive breast cancer who received a delayed DIEP flap breast reconstruction and a control cohort of individually matched women with unilateral breast cancer who underwent mastectomy but no autologous breast reconstruction. Matching criteria comprised: year of diagnosis (+/-3 years), age at diagnosis (+/-5 years), type of cancer and demographic region. The primary endpoints were local recurrence or distant metastasis, and overall mortality was a secondary endpoint. Absolute risk of recurrent disease and mortality was analysed, and relative risks were estimated using Cox proportional hazards analysis. RESULTS: There were 225 women in the DIEP cohort and 450 in the no-DIEP cohort. The median follow-up time was 125 months. There was no difference in absolute risk of recurrence between the cohorts. The hazard ratio for breast cancer recurrence in DIEP versus no-DIEP cohorts was 0·76 (95 per cent c.i. 0·47 to 1·21). CONCLUSION: There is no increased risk in breast cancer recurrence after delayed DIEP flap reconstruction compared with mastectomy alone.

Risk of ischemic heart disease after radiotherapy for ductal carcinoma in situ.

PURPOSE: The use of adjuvant radiotherapy (RT) in the management of ductal carcinoma in situ (DCIS) is increasing. Left-sided breast irradiation may involve exposure of the heart to ionising radiation, increasing the risk of ischemic heart disease (IHD). We examined the incidence of IHD in a population-based cohort of women with DCIS. METHODS: The Breast Cancer DataBase Sweden (BCBase) cohort includes women registered with invasive and in situ breast cancers 1992-2012 and age-matched women without a history of breast cancer. In this analysis, 6270 women with DCIS and a comparison cohort of 31,257 women were included. Through linkage with population-based registers, data on comorbidity, socioeconomic status and incidence of IHD was obtained. Hazard ratios (HR) for IHD with 95% confidence intervals (CI) were analysed. RESULTS: Median follow-up time was 8.8 years. The risk of IHD was not increased for women with DCIS versus women in the comparison cohort (HR 0.93; 95% CI 0.82-1.06), after treatment with radiotherapy versus surgery alone (HR 0.77; 95% CI 0.60-0.98) or when analysing RT by laterality (HR 0.85; 95% CI 0.53-1.37 for left-sided versus right-sided RT). CONCLUSIONS: The risk of IHD was lower for women with DCIS allocated to RT compared to non-irradiated women and to the comparison cohort, probably due to patient selection. Comparison of RT by laterality did not show any over-risk for irradiation of the left breast.

Meta-analysis of neoadjuvant therapy and its impact in facilitating breast conservation in operable breast cancer.

BACKGROUND: Neoadjuvant therapy (NAT) for operable breast cancer may facilitate more breast-conserving surgery (BCS). It seems, however, that this benefit is not being realized fully. METHODS: A systematic review of the literature was performed. RCTs were included. The criteria for inclusion were: documentation of surgical assessment before and after NAT, surgery performed (BCS or mastectomy), and clinical and pathological responses. RESULTS: A total of 1452 patients from seven RCTs met the inclusion criteria. After NAT, the feasibility of BCS increased from 43·3 to 60·4 per cent (P < 0·001), but BCS was performed in only 51·8 per cent (P = 0·04). Only 31 per cent of patients who became eligible for BCS (assessed on clinical response) underwent BCS (pooled rate ratio 0·31, 95 per cent c.i. 0·22 to 0·44; P < 0·001). Of the mastectomy candidates who achieved a pathological complete response after NAT, only 41 per cent underwent BCS (pooled rate ratio 0·41, 0·23 to 0·74; P = 0·003). The main factors that influenced the decision not to shift to BCS, even though it was feasible, were clinical assessment before NAT, multicentricity and tumour size at presentation. CONCLUSION: Breast surgery performed after NAT does not reflect tumour response, resulting in potentially unnecessary radical surgery, especially mastectomy. The barriers to maximizing the surgical benefits of NAT need to be better understood and explored.

Simplifying Logistics and Avoiding the Unnecessary in Patients With Breast Cancer Undergoing Sentinel Node Biopsy. A Prospective Feasibility Trial of the Preoperative Injection of Super Paramagnetic Iron Oxide Nanoparticles.

PURPOSE: Sentinel node is routinely localized with the intraoperative use of a radioactive tracer, involving challenging logistics. Super paramagnetic iron oxide nanoparticle is a non-radioactive tracer with comparable performance that could allow for preoperative localization, would simplify the procedure, and possibly be of value in axillary mapping before neoadjuvant treatment. The current trial aimed to determine the a priori hypothesis that the injection of super paramagnetic iron oxide nanoparticles in the preoperative period for the localization of the sentinel node is feasible. METHODS: This is a prospective feasibility trial, conducted from 9 September 2014 to 22 October 2014 at Uppsala University Hospital. In all, 12 consecutive patients with primary breast cancer planned for resection of the primary and sentinel node biopsy were recruited. Super paramagnetic iron oxide nanoparticles were injected in the preoperative visit in the outpatient clinic. The radioactive tracer (99mTc) and the blue dye were injected perioperatively in standard fashion. A volunteer was injected with super paramagnetic iron oxide nanoparticles to follow the decline in the magnetic signal in the sentinel node over time. The primary outcome was successful sentinel node detection. RESULTS: Super paramagnetic iron oxide nanoparticles' detection after preoperative injection (3-15 days) was successful in all cases (100%). In the volunteer, axillary signal was presented for 4 weeks. No adverse effects were noted. Conclusion and relevance: Preoperative super paramagnetic iron oxide nanoparticles' injection is feasible and leads to successful detection of the sentinel node. That may lead to simplified logistics as well as the identification, sampling, and marking of the sentinel node in patients planned for neoadjuvant treatment.

Superparamagnetic iron oxide nanoparticles as the sole method for sentinel node biopsy detection in patients with breast cancer.

BACKGROUND: Sentinel node biopsy (SNB) using superparamagnetic iron oxide (SPIO) nanoparticles is a novel method in breast cancer. Several studies have verified the non-inferiority of SPIO compared with the standard use of radioisotope 99m Tc with or without blue dye. The aim of the MONOS study presented here was to evaluate the use of SPIO as a sole tracer and the efficacy of tracer injection in the preoperative setting. METHODS: This prospective cohort study was carried out in two hospitals, one using 99m Tc and the other SPIO. 99m Tc was injected in the morning of the day of surgery or the day before. SPIO was either injected before surgery in the outpatient clinic or 1 h before the operation. RESULTS: A total of 338 consecutive patients with breast cancer underwent 343 procedures; SPIO nanoparticles were used in 184 procedures and 99m Tc-labelled tracer in 159. Detection rates for SPIO and 99m Tc were 95·6 and 96·9 per cent respectively (P = 0·537). All nodes with SPIO uptake were coloured brown. Fewer nodes were retrieved with SPIO (mean 1·35 versus 1·89), regardless of whether blue dye was used (P < 0·001). Preoperative SPIO injection (58·7 per cent of procedures), a median of 16 (range 2-27) days before the procedure, was associated with a better tracer-specific detection rate (95·3 versus 86 per cent; P = 0·031) and retrieval of more nodes (mean 1·43 versus 1·03; P < 0·001) than perioperative administration. Skin staining was present in 39·9 per cent of patients, and was related to breast-conserving surgery and periareolar injection. CONCLUSION: The use of SPIO alone is a safe alternative, with results comparable to those of the standard dual technique using 99m Tc and blue dye. The efficacy of injection in the preoperative setting simplifies logistics and improves performance. Skin staining can be prevented by a deeper peritumoral injection.

Risk of death from breast cancer after treatment for ductal carcinoma in situ.

BACKGROUND: Studies to date have failed to demonstrate any survival benefit from preventing local recurrence after treatment for ductal breast carcinoma in situ (DCIS). Patient- and tumour-related risk factors for death from breast cancer in women with a primary DCIS were analysed here in a large case-control study. METHODS: A nested case-control study was conducted in a population-based cohort of women with primary DCIS between 1992 and 2012. Women who later died from breast cancer were identified. Four controls per case were selected randomly by incidence density sampling. Medical records and pathology reports were retrieved. Conditional logistic regression was used to calculate odds ratios (ORs) and 95 per cent confidence intervals for risk of death from breast cancer. RESULTS: From a cohort of 6964 women, 96 who died from breast cancer were identified and these were compared with a group of 318 controls. Tumour size over 25 mm or multifocal DCIS (OR 2·55, 95 per cent c.i. 1·53 to 4·25), a positive or uncertain margin status (OR 3·91, 1·59 to 9·61) and detection outside the screening programme (OR 2·12, 1·16 to 3·86) increased the risk of death from breast cancer. The risks were not affected by age or type of treatment. In the multivariable analysis, tumour size (OR 1·95, 1·06 to 3·67) and margin status (OR 2·69, 1·15 to 7·11) remained significant. CONCLUSION: In the present study, large tumour size and positive or uncertain margin status were associated with a higher risk of death from breast cancer after treatment for primary DCIS. More extensive treatment was not associated with lower risk, which may be due to confounding by indication, or indicate that some DCIS has an inherent potential for metastatic spread.

Clonal alteration of breast cancer receptors between primary ductal carcinoma in situ (DCIS) and corresponding local events.

BACKGROUND: Emerging data propose biomarker alteration due to clonal selection between the primary invasive breast cancer and corresponding metastases. In addition, impact on survival has been demonstrated. The present study investigates the relationship between the oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between primary ductal carcinoma in situ (DCIS) and intra-individually matched ipsilateral event. MATERIALS AND METHODS: The cohort includes 1504 patients, diagnosed with a primary DCIS between 1986 and 2004. Of the 274 patients who developed a local relapse, 135 developed a new in situ carcinoma and 139 an invasive cancer up to 31st December 2011. ER and PR were identified by immunohistochemistry (IHC) and HER2 by silver-enhanced in situ hybridisation (SISH) as well as IHC. RESULTS: ER (n=112), PR (n=113) and HER2 (n=114) status from both the primary DCIS and the corresponding relapse were assessed and were demonstrated to be discordant in 15.1%, 29.2% and 10.5% respectively. The receptor conversion was both from negative to positive and from positive to negative with no general pattern being seen in spite of sub-dividing into in situ relapse and invasive relapse. However, primary DCIS was HER2 positive in 40.3% whereas in situ and invasive relapses were HER2 positive in 42.9% and 34.5% respectively. CONCLUSIONS: Receptor conversion for ER, PR and HER2 status occurred between primary DCIS and corresponding local relapse in 10-30%. This study could not confirm that HER2 overexpression in primary DCIS had any impact on tumour progression to invasive cancer which has been proposed.

Breast cancer survival and stage at diagnosis in Australia, Canada, Denmark, Norway, Sweden and the UK, 2000-2007: a population-based study.

BACKGROUND: We investigate whether differences in breast cancer survival in six high-income countries can be explained by differences in stage at diagnosis using routine data from population-based cancer registries. METHODS: We analysed the data on 257,362 women diagnosed with breast cancer during 2000-7 and registered in 13 population-based cancer registries in Australia, Canada, Denmark, Norway, Sweden and the UK. Flexible parametric hazard models were used to estimate net survival and the excess hazard of dying from breast cancer up to 3 years after diagnosis. RESULTS: Age-standardised 3-year net survival was 87-89% in the UK and Denmark, and 91-94% in the other four countries. Stage at diagnosis was relatively advanced in Denmark: only 30% of women had Tumour, Nodes, Metastasis (TNM) stage I disease, compared with 42-45% elsewhere. Women in the UK had low survival for TNM stage III-IV disease compared with other countries. CONCLUSION: International differences in breast cancer survival are partly explained by differences in stage at diagnosis, and partly by differences in stage-specific survival. Low overall survival arises if the stage distribution is adverse (e.g. Denmark) but stage-specific survival is normal; or if the stage distribution is typical but stage-specific survival is low (e.g. UK). International differences in staging diagnostics and stage-specific cancer therapies should be investigated.

Cyclin B1 is a prognostic proliferation marker with a high reproducibility in a population-based lymph node negative breast cancer cohort.

A large proportion of women with lymph node negative breast cancer do not benefit from chemotherapy. Proliferation markers have been shown to recognize patients at high risk for recurrence. The Ki67 protein has recently been included in the St Gallen guidelines. The authors investigated the prognostic importance of cyclin B1 in node negative breast cancer and included a study of reproducibility. In a population-based case-control study, 190 women who died from breast cancer were defined as cases and 190 women alive at the time for the corresponding case's death were defined as controls. Inclusion criteria were tumor size

Quality aspects of the tissue microarray technique in a population-based cohort with ductal carcinoma in situ of the breast.

AIMS: Tissue microarray (TMA) is an efficient technique for analysis of molecular markers. Prospectively collected samples have been reported to give excellent concordance between TMA data and corresponding whole-sections. The aim was to evaluate the usefulness of TMA in a population-based cohort of 213 women with ductal carcinoma in situ of the breast (DCIS). METHODS AND RESULTS: We studied immunohistochemical HER2, oestrogen (ER) and progesterone (PR) receptor status. The prognostic impact was similar for all markers comparing whole sections and TMAs. The proportion of positive tumours was similar regarding HER2 and ER, whereas PR tumours were more frequently positive in the TMAs (P = 0.007). The concordance was 80% (kappa value 0.63) between original sections and TMAs. The proportion of successfully analysed tumours was 70%. Smaller tumours had a lower ratio (P < 0.0001) and a larger proportion of mismatched results (P = 0.05). CONCLUSIONS: Retrospective analyses of tumours from cohorts with long-term follow-up are indispensable. We have shown that the TMA technique is a useful tool for high-throughput analysis of DCIS. However, our study has pinpointed some technical hazards within a population-based cohort, including many small lesions and the poor condition of some donor blocks. Mismatched results may be due to tumour heterogeneity.

Search for DNA of exogenous mouse mammary tumor virus-related virus in human breast cancer samples.

Earlier reports of a human exogenous retrovirus (HMTV) related closely to mouse mammary tumor virus (MMTV) led us to search for these viral sequences in breast cancer tissues and normal tissues. A real-time PCR was developed based on MMTV and published HMTV envelope sequences. The real-time PCR method can detect one to ten copies of MMTV target DNA. Tissue samples were collected prospectively from 18 breast cancer patients and 11 non-malignant control cases, as well as peripheral blood leukocytes from the same women. Despite the high sensitivity of the real-time PCR method used, none of the samples were positive for HMTV DNA or RNA. The absence of HMTV DNA in both breast cancer samples and controls indicates either that the concentration of putative HMTV DNA in the breast cancers was too low for detection or that it did not exist there.

Cyclooxygenase-2 inhibition: effects on tumour growth, cell cycling and lymphangiogenesis in a xenograft model of breast cancer.

Cyclooxygenase-2 (COX-2) is associated with poor-prognosis breast cancer. We used a nude mouse xenograft model to determine the effects of COX-2 inhibition in breast cancer. Oestrogen receptor (ER)-positive MCF7/HER2-18 and ER-negative MDAMB231 breast cancer cell lines were injected into nude mice and allowed to form tumours. Mice then received either chow containing Celecoxib (a COX-2 inhibitor) or control and tumour growth measured. Tumour proliferation, apoptosis, COX-2, lymphangiogenesis and angiogenesis were assessed by immunohistochemistry (IHC), Western blotting or Q-PCR. Celecoxib inhibited median tumour growth in MCF7/HER2-18 (58.7%, P=0.029) and MDAMB231 (46.3%, P=0.0002) cell lines compared to control. Cyclooxygenase-2 expression decreased following Celecoxib treatment (MCF7/HER2-18 median control 65.3% vs treated 22.5%, P=0.0001). Celecoxib increased apoptosis in MCF7/HER2-18 tumours (TUNEL 0.52% control vs 0.73% treated, P=0.0004) via inactivation of AKT (median pAKT(ser473) 57.3% control vs 35.5% treated, P=0.0001--confirmed at Western blotting). Q-PCR demonstrated decreased podoplanin RNA (lymphangiogenesis marker) in the MCF7/HER2-18 - median 2.9 copies treated vs 66.6 control (P=0.05) and MDAMB231-treated groups--median 160.7 copies vs 0.05 control copies (P=0.015), confirmed at IHC. Cyclooxygenase-2 is associated with high levels of activated AKT(ser473) and lymphangiogenesis in breast cancer. Cyclooxygenase-2 inhibition decreases tumour growth, and may potentially decrease recurrence, by inactivating AKT and decreasing lymphangiogenesis.

Will early detection of non-axillary sentinel nodes affect treatment decisions?

Axillary lymph node involvement is the best prognostic factor for breast cancer survival. Staging breast cancers by axillary dissection remains standard management and is part of the UK national guidelines for breast cancer treatment. In the presence of involved axillary lymph nodes best treatment has been shown to be axillary clearance (Fentiman and Mansell, 1991), but clearly for women whose nodes are uninvolved avoidance of morbidity is optimal and this will be achieved by minimal dissection of the axilla. Thus, for node-negative women the introduction of the sentinel node biopsy technique may revolutionise the approach to the axilla. These will be women with mammographic screen detected small well and moderately differentiated tumours (Hadjiloucas and Bundred, 2000). The impact of sentinel node biopsy in women who have symptomatic large tumours is unproven, and around half of these women will require a second procedure to clear their axilla or radiotherapy as treatment. Even for those women found to have involved sentinel lymph nodes the ability to use early systemic chemotherapy followed by axillary clearance or radiotherapy may provide long-term survival gains. Sentinel node biopsy should not, however, become routine practice until randomised controlled trials have proven its benefit and safety in reducing morbidity. Several randomised controlled trials (including ALMANAC) are currently underway.

Ductal carcinoma in situ of the breast: a new phenotype classification system and its relation to prognosis.

In a study of invasive breast cancer, multiple correspondence analysis (MCA) revealed clustering of eight pathobiological variables. Two different phenotypes were distinguished by an index calculated on the basis of the variables (histologic grade, necrosis, lymphoid infiltration, number of mitosis and expression of c-erbB-2, p53, progesterone receptor and Bcl-2). Phenotype A lesions share most of the features of normal breast tissue. Phenotype B looks more malignant, has a higher early recurrence rate and is more frequently seen in younger patients. Our aim was to see if ductal breast carcinoma in situ (DCIS) could be divided into the same phenotypes. One hundred and eighty DCIS were investigated. Association between the eight variables was studied in 2 x 2 models. The phenotype index was calculated by summing weights for the variables in the MCA. All variables were associated, except Bcl-2. DCIS was divided in two phenotypes. Thirty-three tumours were Phenotype A and 147 Phenotype B. The mean age at diagnosis was 65.5 and 58.4 years for Phenotypes A and B, respectively (p = 0.0012). No difference regarding local relapse free survival was seen. Two phenotypes were distinguished in DCIS, similar to invasive breast cancer. In an earlier study, 45% of the invasive cancers were classified as Phenotype B. In this study, 82% of DCIS were Phenotype B. This may indicate that invasive breast cancer of Phenotype B is derived from DCIS of Phenotype B. The distribution of DCIS phenotypes with a small proportion of Phenotype A DCIS may be due to that Phenotype A DCIS is less likely to be detected by mammography, or that some invasive breast cancers of Phenotype A progress to invasiveness without passing the in situ phase.

Tumour markers in breast carcinoma correlate with grade rather than with invasiveness.

Ductal breast carcinoma in situ (DCIS) is regarded as a precursor to invasive breast cancer. The progression from in situ to invasive cancer is however little understood. We compared some tumour markers in invasive and in situ breast carcinomas trying to find steps in this progression. We designed a semi-experimental setting and compared histopathological grading and tumour marker expression in pure DCIS (n = 194), small invasive lesions (n = 127) and lesions with both an invasive and in situ component (n = 305). Grading was done according to the Elston-Ellis and EORTC classification systems, respectively. Immunohistochemical staining was conducted for p53, c-erbB-2, Ki-67, ER, PR, bcl-2 and angiogenesis. All markers correlated with grade rather than with invasiveness. No marker was clearly associated with the progression from in situ to invasiveness. The expression of tumour markers was almost identical in the 2 components of mixed lesions. DCIS as a group showed a more 'malignant picture' than invasive cancer according to the markers, probably, due to a higher proportion of poorly differentiated lesions. The step between in situ and invasive cancer seems to occur independently of tumour grade. The results suggest that well-differentiated DCIS progress to well-differentiated invasive cancer and poorly differentiated DCIS progress to poorly differentiated invasive cancer.

Risk factors for subsequent invasive breast cancer and breast cancer death after ductal carcinoma in situ: a population-based case-control study in Sweden.

In a case-control study derived from a cohort of 4661 women with a primary carcinoma in situ of the breast, we investigated age at diagnosis, mode of detection, tumor characteristics, and primary therapy, as prognostic factors for developing invasive breast cancer or dying from breast cancer. From all of the women with a primary carcinoma in situ reported to the Swedish Cancer Registry from 1960 through 1992, we selected as cases all of the women with a ductal carcinoma in situ who later died of breast cancer (n = 39) or who developed a subsequent invasive cancer in either breast (n = 118). From this cohort, we also selected controls matched to the cases by year of diagnosis and health care region. We conducted univariate and multivariate analyses to study the association between risk of invasive cancer or death and the different risk factors. Large size, diameter > or = 25 mm [odds ratio (OR), 3.5; 95% confidence interval (CI), 1.1-11.4] and multifocality (OR, 3.9; 95% CI, 1.2-12.7) increased the risk of breast cancer death in univariate analysis. Postoperative radiotherapy (OR, 0.1; 95% CI, 0.0-1.0) and mastectomy (OR, 0.1-95% CI, 0.0-0.5) lowered the risk of an ipsilateral invasive cancer in multivariate analysis. The risk pattern by treatment category differed between those who had an ipsilateral invasive cancer and those who either had a contralateral cancer or died from breast cancer. The driving forces behind local and generalized disease may differ. Because confounding by indication may influence the effects of different treatments, the results should be interpreted with caution.

Risk of subsequent invasive breast cancer after breast carcinoma in situ.

The standardised incidence rates for invasive breast cancer were estimated in a cohort of 3455 women with a primary lobular or ductal carcinoma in situ of the breast.

Ductal carcinoma in situ of the breast from a population-defined cohort: an evaluation of new histopathological classification systems.

The increased incidence of ductal carcinoma in situ of the breast (DCIS) in the era of mammography screening requires a deeper knowledge of the biology of the disease and calls for a suitable classification system to optimise therapy. Our aim was to evaluate the correlation to prognosis for two new classification systems of DCIS. The histopathological specimens from 195 women consecutively diagnosed between 1986 and 1994 with a primary DCIS were re-classified by two separate observers using the system proposed by an European Organization for Research and Treatment of Cancer (EORTC) working group and the Van Nuys system. The relapse-free survival (RFS) by histopathological subgroup and by nuclear grade only was estimated for women treated with breast conserving surgery (n = 149). Thirty-two local recurrences occurred among 149 women (mean follow-up time 59 months). No distant recurrences or breast cancer deaths were reported. The women in the group with the highest differentiation according to the EORTC classification had no recurrences. RFS did not differ appreciably between the two other groups. This was true also after stratification for radiotherapy. We found no statistically significant difference in RFS between the three groups in the Van Nuys classification. There was an overall agreement between the observers in 79% and 64% of the cases, according to the EORTC and Van Nuys systems, respectively. We were able to define one group with highly differentiated lesions and an excellent prognosis with the EORTC classification. Further classification into intermediate and low differentiated lesions did not help predict RFS.