Long-Term Prognostication for 20 114 Women With Small and Node-Negative Breast Cancer (T1abN0).

Background: Although small, node-negative breast cancer (ie, T1abN0) constitutes 20% of all newly diagnosed breast cancers, data on prognosis and prognostic factors are limited. Methods: We conducted a population-based cohort study including 20 114 Swedish women treated for T1abN0 breast cancer from 1977 onward. Patient and tumor data were collected from Swedish breast cancer registries. Cohort subjects were followed through linkage to the Cause of Death Register. We calculated the cumulative incidence of breast cancer-specific and overall death and used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: During a median follow-up of 9.1 years (range = 0-38), 915 women died of breast cancer and 5416 of any cause. The 10-, 20-, and 30-year cumulative incidences of breast cancer death were 3.4% (95% CI = 3.1% to 3.7%), 7.6% (95% CI = 7.1% to 8.2%), and 10.5% (95% CI = 9.6% to 11.4%), respectively. The multivariable hazard ratios and 95% confidence intervals of breast cancer death were 0.92 (95% CI = 0.88 to 0.97) for each additional calendar year of diagnosis, 4.38 (95% CI = 2.79 to 6.87) for grade 3 vs grade 1 tumors, 0.43 (95% CI = 0.31 to 0.62) for progesterone receptor-positive vs progesterone receptor-negative disease, and 2.01 (95% CI = 0.99 to 4.07) for HER2-positive vs HER2-negative disease. Women with grade 3 vs grade 1 tumors had a 56% increased risk of death from any cause (HR = 1.56, 95% CI = 1.30 to 1.88). Conclusions: The risk of breast cancer death in T1abN0 disease continues to increase steadily beyond 10 years after diagnosis, has improved over time, and varies substantially by tumor characteristics.

Differences in intra-tumoral macrophage infiltration and radiotherapy response among intrinsic subtypes in pT1-T2 breast cancers treated with breast-conserving surgery.

Breast cancer (BC) intrinsic subtype classification is based on the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and proliferation marker Ki-67. The expression of these markers depends on both the genetic background of the cancer cells and the surrounding tumor microenvironment. In this study, we explore macrophage traits in cancer cells and intra-tumoral M2-macrophage infiltration (MI) in relation to intrinsic subtypes in non-metastatic invasive BC treated with breast conserving surgery, with and without postoperative radiotherapy (RT). Immunostaining of M2-macrophage-specific antigen CD163 in cancer cells and MI were evaluated, together with ER, PR, HER2, and Ki-67-expression in cancer cells. The tumors were classified into intrinsic subtypes according to the ESMO guidelines. The immunostaining of these markers, MI, and clinical data were analyzed in relation to ipsilateral local recurrence (ILR) as well as recurrence-free (RFS) and disease-free specific (DFS) survival. BC intrinsic subtypes are associated with T-stage, Nottingham Histologic Grade (NHG), and MI. Macrophage phenotype in cancer cells is significantly associated with NHG3-tumors. Significant differences in macrophage infiltration were observed among the intrinsic subtypes of pT1-T2 stage BC. Shorter RFS was observed in luminal B HER2neg tumors after RT, suggesting that this phenotype may be more resistant to irradiation. Ki-67-expression was significantly higher in NHG3 and CD163-positive tumors, as well as those with moderate and high MI. Cancer cell ER expression is inversely related to MI and thus might affect the clinical staging and assessment of BC.

Tumor cell expression of CD163 is associated to postoperative radiotherapy and poor prognosis in patients with breast cancer treated with breast-conserving surgery.

PURPOSE: Cancer cell fusion with macrophages results in highly tumorigenic hybrids that acquire genetic and phenotypic characteristics from both maternal cells. Macrophage traits, exemplified by CD163 expression, in tumor cells are associated with advanced stages and poor prognosis in breast cancer (BC). In vitro data suggest that cancer cells expressing CD163 acquire radioresistance. METHODS: Tissue microarray was constructed from primary BC obtained from 83 patients treated with breast-conserving surgery, 50% having received postoperative radiotherapy (RT) and none of the patients had lymph node or distant metastasis. Immunostaining of CD163 in cancer cells and macrophage infiltration (MI) in tumor stroma were evaluated. Macrophage:MCF-7 hybrids were generated by spontaneous in vitro cell fusion. After irradiation (0, 2.5 and 5 Gy γ-radiation), both hybrids and their maternal MCF-7 cells were examined by clonogenic survival. RESULTS: CD163-expression by cancer cells was significantly associated with MI and clinicopathological data. Patients with CD163-positive tumors had significantly shorter disease-free survival (DFS) after RT. In vitro generated macrophage:MCF-7 hybrids developed radioresistance and exhibited better survival and colony forming ability after radiation compared to maternal MCF-7 cancer cells. CONCLUSIONS: Our results suggest that macrophage phenotype in tumor cells results in radioresistance in breast cancer and shorter DFS after radiotherapy.

Fusion between M2-macrophages and cancer cells results in a subpopulation of radioresistant cells with enhanced DNA-repair capacity.

Cell fusion is a natural biological process in normal development and tissue regeneration. Fusion between cancer cells and macrophages results in hybrids that acquire genetic and phenotypic characteristics from both maternal cells. There is a growing body of in vitro and in vivo data indicating that this process also occurs in solid tumors and may play a significant role in tumor progression. However, investigations of the response of macrophage:cancer cell hybrids to radiotherapy have been lacking. In this study, macrophage:MCF-7 hybrids were generated by spontaneous in vitro cell fusion. After irradiation, both hybrids and their maternal MCF-7 cells were treated with 0 Gy, 2.5 Gy and 5 Gy γ-radiation and examined by clonogenic survival and comet assays at three time points (0 h, 24 h, and 48 h). Compared to maternal MCF-7 cells, the hybrids showed increased survival fraction and plating efficiency (colony formation ability) after radiation. The hybrids developed less DNA-damage, expressed significantly lower residual DNA-damage, and after higher radiation dose showed less heterogeneity in DNA-damage compared to their maternal MCF-7 cells. To our knowledge this is the first study that demonstrates that macrophage:cancer cell fusion generates a subpopulation of radioresistant cells with enhanced DNA-repair capacity. These findings provide new insight into how the cell fusion process may contribute to clonal expansion and tumor heterogeneity. Furthermore, our results provide support for cell fusion as a mechanism behind the development of radioresistance and tumor recurrence.

Effect of radiotherapy after breast-conserving surgery for ductal carcinoma in situ: 20 years follow-up in the randomized SweDCIS Trial.

PURPOSE: Four randomized studies show that adjuvant radiotherapy (RT) lowers the risk of subsequent ipsilateral breast events (IBEs) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) by approximately 50% after 10 to 15 years. We present 20 years of follow-up data for the SweDCIS trial. PATIENTS AND METHODS: Between 1987 and 1999 1,046 women were randomly assigned to RT or not after BCS for primary DCIS. Results up to 2005 have been published, and we now add another 7 years of follow-up. All breast cancer events and causes of death were registered. RESULTS: There were 129 in situ and 129 invasive IBEs. Absolute risk reduction in the RT arm was 12.0% at 20 years (95% CI, 6.5 to 17.7), with a relative risk reduction of 37.5%. Absolute reduction was 10.0% (95% CI, 6.0 to 14.0) for in situ and 2.0% (95% CI, -3.0 to 7.0) for invasive IBEs. There was a nonstatistically significantly increased number of contralateral events in the RT arm (67 v 48 events; hazard ratio, 1.38; 95% CI, 0.95 to 2.00). Breast cancer-specific death and overall survival were not influenced. Younger women experienced a relatively higher risk of invasive IBE and lower effect of RT. The hazard over time looked different for in situ and invasive IBEs. CONCLUSION: Use of adjuvant RT is supported by 20-year follow-up. Modest protection against invasive recurrences and a possible increase in contralateral cancers still call for a need to find groups of patients for whom RT could be avoided or mastectomy with breast reconstruction is indicated.

Super-selective venous sampling in conjunction with quickPTH for patients with persistent primary hyperparathyroidism: report of five cases.

Selective venous sampling (SVS) helps to interpret imaging results in patients with persistent primary hyperparathyroidism (pHPT). However, one of the drawbacks of conventional SVS may be low "spatial resolution", depending on the sample size. We modified SVS in the following way: first, patients underwent conventional SVS with up to 11 parathyroid hormone (PTH) samples taken. The quickPTH assay was used to measure PTH levels. The patients subsequently underwent super-selective venous sampling (super-SVS) in the region with the highest quickPTH level in the same session. The subjects were five consecutive patients with persistent pHPT investigated by various imaging techniques, none of which was considered conclusive. Therefore, all five patients underwent super-SVS, which was done successfully in four. Re-evaluation of the imaging results of these four patients resulted in localization of the parathyroid adenoma. Curative surgery was performed successfully in all four patients during the study period. Super-SVS increases the "spatial resolution" of conventional SVS and may have advantages when imaging results of patients with persistent pHPT are interpreted. Its true value must be analyzed in larger studies.

Improved survival for women with stage I breast cancer in south-east Sweden: a comparison between two time periods before and after increased use of adjuvant systemic therapy.

PURPOSE: Continuous minor steps of improvement in the management of breast cancer have resulted in decreased mortality rates during the last decades. The aim of this study was to compare the clinical outcome of patients with stage I breast cancer diagnosed during two time periods that differed with respect to adjuvant systemic therapy. MATERIAL AND METHODS: The studied population consisted of all women < 60 years of age, who were diagnosed breast cancer stage I between 1986 and 1999 in south-east Sweden, a total of 1 407 cases. The cohort was divided into two groups based on the management programmes of 1986 and 1992, hereafter referred to as Period 1 and Period 2. Before 1992 the only adjuvant systemic therapy recommended was tamoxifen for hormone receptor positive patients aged 50 years or older. During Period 2 the use of adjuvant treatment was extended to younger patients at high risk, identified by a high tumour S-phase fraction, with either hormonal or cytotoxic treatment. RESULTS: The estimated distant recurrence-free survival rate was significantly higher during Period 2 than during Period 1 (p = 0.008). Subgroup analysis showed that the most evident reduction of distant recurrence risk was among hormone receptor-negative patients (HR = 0.58, 95% CI 0.31-1.09, p = 0.09) and among patients with a high tumour S-phase fraction (HR = 0.53, 0.30-0.93, p = 0.028). The risk reduction between the periods was still statistically significant in multivariate analysis when adjusting for different tumour characteristics and treatment modalities, indicating an influence of other factors not controlled for. One such factor may be the duration of tamoxifen treatment, which likely was more frequently five years during Period 2 than during Period 1. CONCLUSIONS: We conclude that the causes of the increase in distant recurrence free survival for women with breast cancer stage I are complex. The results support though that high-risk subgroups of stage I breast cancer patients did benefit from increased use of systemic therapy as a consequence of an updated management programme.

Absolute risk reductions for local recurrence after postoperative radiotherapy after sector resection for ductal carcinoma in situ of the breast.

PURPOSE: Evaluate the effects of radiotherapy after sector resection for ductal carcinoma in situ of the breast (DCIS) in patient groups as defined by age, size of the lesion, focality, completeness of excision and mode of detection. PATIENTS AND METHODS: A total of 1,067 women in Sweden were randomly assigned to either postoperative radiotherapy (RT) or control from 1987 to 1999, and 1,046 were followed for a mean of 8 years. The main outcome was new ipsilateral breast cancer events and distant metastasis-free survival analyzed according to intention to treat. RESULTS: There were 64 ipsilateral events in the RT arm and 141 in the control group corresponding to a risk reduction of 16.0 percentage points at 10 years (95% CI, 10.3% to 21.6%) and a relative risk of 0.40 (95% CI, 0.30 to 0.54). There was no statistically significant difference in distant metastasis-free survival. There was an effect modification by age, yielding a low effect of RT in women younger than 50, but substantial protection in women older than 60 years. The age effect was not confounded by focality, lesion size, completeness of excision, or detection mode. There was no group as defined by our stratification variables that had a low risk without radiotherapy. CONCLUSION: Our results indicate that younger women have a low protective effect of conventional RT after sector resection. Older women benefit substantially. We caution that the age effect was seen in a subgroup analysis. Further search with conventional clinical variables for a low risk group that does not need RT does not seem fruitful.

SweDCIS: Radiotherapy after sector resection for ductal carcinoma in situ of the breast. Results of a randomised trial in a population offered mammography screening.

We studied the effect of postoperative radiotherapy (RT) after breast sector resection for ductal carcinoma in situ (DCIS). The study protocol stipulated radical surgery but microscopically clear margins were not mandatory. We randomised 1,046 operated women to postoperative RT or control between 1987 and 1999. The primary endpoint was ipsilateral local recurrence. Secondary endpoints were contralateral breast cancer, distant metastasis and death. After a median follow-up of 5.2 years (range 0.1-13.8) there were 44 recurrences in the RT group corresponding to a cumulative incidence of 0.07 (95% confidence interval (CI) 0.05-0.10). In the control group there were 117 recurrences giving a cumulative incidence of 0.22 (95% CI 0.18-0.26) giving an overall hazard ratio of 0.33 (95% CI 0.24-0.47, p < 0.0001). Twenty two percent of the patients had microscopically unknown or involved margins. We found no evidence for different effects of RT on the relative risk of invasive or in situ recurrence. Secondary endpoints did not differ. Women undergoing sector resection for DCIS under conditions of population based screening mammography benefit from postoperative RT to the breast. Seven patients needed RT-treatment to prevent one recurrence.