Breast conservation in ductal carcinoma in situ (DCIS): what defines optimal margins?

The introduction of mammographic screening has resulted in a rise in the detection rate of ductal carcinoma in situ (DCIS), currently accounting for one-fifth of screen-detected breast cancers. Although 60-70% of DCIS are treated with breast-conserving surgery (BCS) with or without radiotherapy, the frequency of subsequent surgery to re-excise positive margins in order to reduce the probability of recurrences remains high. DCIS recurrence is associated not only with financial, health and psychological implications; approximately half these recurrences are invasive disease. An appropriate margin width for patients undergoing BCS for invasive breast cancer has been largely agreed. Although there is a perception that such recommendations may be applicable to DCIS, major differences exist which may affect this application. Importantly, DCIS patients often do not receive systemic adjuvant (endocrine) therapy and not all receive radiotherapy in routine practice. There is evidence that wide margins (i.e. >10 mm) confer better protection against recurrence than positive (i.e. 0 mm) margins; however, there remains a debate concerning the optimum margin width between 0 and 10 mm. Previous studies have demonstrated that radiation therapy may not compensate for lack of re-excision in those patients with positive or close margins, while wide margins will inevitably compromise cosmesis and patients' body image perception. This review aims to address the clinical question of the minimal margin width in DCIS treated with BCS that is associated with the lowest recurrence rate and when, therefore, further surgical intervention for re-excision can be safely avoided. A range of clinical circumstances that might affect this are considered.

Age-Related Biology of Early-Stage Operable Breast Cancer and Its Impact on Clinical Outcome.

As age advances, breast cancer (BC) tends to change its biological characteristics. This study aimed to explore the natural progression of such changes. The study included 2383 women with clinically T0-2N0-1M0 BC, managed by primary surgery and optimal adjuvant therapy in a dedicated BC facility. Tissue micro-arrays were constructed from their surgical specimens and indirect immunohistochemistry was used for analysis of a large panel (n = 16) of relevant biomarkers. There were significant changes in the pattern of expression of biomarkers related to luminal (oestrogen receptor (ER), progesterone receptors (PgR), human epidermal growth factor receptor (HER-2), E-cadherin, MUC1, bcl2 CK7/8, CK18 and bcl2) and basal (CK5/6, CK14, p53 and Ki67) phenotypes, lymph node stage, histological grade and pathological size when decade-wise comparison was made (p < 0.05). The ages of 40 years and 70 years appeared to be the milestones marking a change of the pattern. There were significantly higher metastasis free and breast cancer specific survival rates among older women with ER positive tumours while there was no significant difference in the ER negative group according to age. Biological characteristics of BC show a pattern of change with advancing age, where 40 years and 70 years appear as important milestones. The pattern suggests <40 years as the phase with aggressive phenotypes, >70 years as the less aggressive phase and 40-70 years being the transitional phase.

Liver Kinase B1-A Potential Therapeutic Target in Hormone-Sensitive Breast Cancer in Older Women.

Background: The role of liver kinase B1 (LKB1), a serine/threonine kinase, has been described in the development of PeutzJagher's syndrome, where a proportion (~45%) of patients have developed breast cancer in their lifetime. Cell line studies have linked LKB1 with oestrogen receptors (ER) and with the Adenosine monophosphate-activated protein kinase (AMPK) pathway for energy metabolism. However, limited studies have investigated protein expression of LKB1 in tumour tissues and its intracellular relationships. This study aimed to investigate the intracellular molecular relationships of LKB1 in older women with early operable primary breast cancer and its correlation with long-term clinical outcome. Methods: Between 1973 and 2010, a consecutive series of 1758 older (≥70 years) women with T0-2N0-1M0 breast carcinoma were managed in a dedicated facility. Of these, 813 patients underwent primary surgery, and 575 had good quality tumour samples available for tissue microarray construction. LKB1 was assessed in 407 cases by indirect immunohistochemistry (IHC). Tumours with 30% or more of cells with cytoplasmic LKB1 expression were considered positive. LKB1 expression was compared with tumour size, histological grade, axillary lymph node stage, ER, PgR, EGFR, HER2, HER3, HER4, BRCA1&2, p53, Ki67, Bcl2, Muc1, E-Cadherin, CD44, basal (CK5, CK5/6, CK14 and CK17) and luminal (CK7/8, CK18 and CK19) cytokeratins, MDM2 and MDM4, and correlated with long-term clinical outcome. Results: Positive LKB1 expression was seen in 318 (78.1%) patients, and was significantly associated with high tumour grade, high Ki67, over-expression of HER2, VEGF, HER4, BRCA2, MDM2 and negative expression of CD44 (p < 0.05). There was no significant correlation with tumour size, axillary lymph node status, ER, PgR, p53, basal or luminal cytokeratins, Bcl2, Muc1, EGFR, HER3, MDM4, E-cadherin and BRCA1. LKB1 did not show any significant influence on survival in the overall population; however, in those patients receiving adjuvant endocrine therapy for ER positive tumours, those with positive LKB1 had significantly better 5-year breast cancer specific survival when compared to those without such expression (93% versus 74%, p = 0.03). Conclusion: LKB1 expression has shown association with poor prognostic factors in older women with breast cancer. However, LKB1 expression appears to be associated with better survival outcome among those patients receiving adjuvant endocrine therapy. Further research is required to explore its potential role as a therapeutic target.

Successful management of elderly breast cancer patients treated without radiotherapy.

BACKGROUND: Breast cancer in the elderly may follow a less aggressive course. There are data suggesting that radiotherapy (RT) following breast conserving surgery (BCS) for invasive carcinoma may not be necessary in some elderly patients. The addition of RT to surgery might constitute an imposition to such patients due to age-related factors. The aim of this study was to assess the efficacy of BCS without adjuvant RT in this group of patients. PATIENTS AND METHODS: A retrospective review of 92 elderly (median age 75 years; range: 70 - 87 years) patients (analysed as 93 'patients' due to one patient having bilateral cancers) managed in a dedicated breast clinic and who underwent BCS for invasive carcinoma was carried out. Eighty-three patients did not receive postoperative RT to the breast (no-RT group) whereas the remaining 10 had RT (RT-group). RESULTS: The median age in this group was 75 (range 70 - 87) years. The mean tumour size was 18 mm with a median follow-up of 37 (range 6 - 142) months. In the no RT group, adjuvant endocrine therapy with tamoxifen was given to 40/53 patients. No patients in the oestrogen receptor (ER) negative group received tamoxifen. The local recurrence (LR) rate in this group was 8.4% (2.4% per year, n = 7/83), with median time to LR of 17 months. In this no-RT group LR was correlated to ER status (2/53 ER+, 5/26ER-, p = 0.024) and margins of excision (n = 1/54 >5 mm, 2/17 1-5 mm, 4/12 <1 mm, p = 0.001). Within the ER positive group the LR rate was 0.92% per annum (0.62% per annum in patients treated with adjuvant tamoxifen, regardless of margin status). Breast cancer specific survival was correlated to histological grade (p < 0.05) and ER status (p < 0.05). CONCLUSION: It would appear that omission of RT following successful BCS in elderly patients with ER positive tumours receiving adjuvant tamoxifen may be acceptable. The LR rate as shown in this retrospective study is highly comparable to that of younger patients treated by conventional therapy. This concept is now being evaluated prospectively following a change in treatment practice.

Prognostic Factors for Local Control in Breast Cancer After Long-term Follow-up in the EORTC Boost vs No Boost Trial: A Randomized Clinical Trial.

IMPORTANCE: Prognostic factors of ipsilateral breast tumor recurrence (IBTR) may change over time following breast-conserving therapy. OBJECTIVE: The EORTC "boost no boost" trial showed that young age and high-grade invasive carcinoma were the most important risk factors for IBTR. This study reanalyses pathological prognostic factors related to IBTR using long-term follow-up. DESIGN, SETTING, AND PARTICIPANTS: Participants included 5569 early-stage breast cancer patients, treated with breast-conserving surgery (BCS) and whole-breast irradiation (WBI), who were randomized between no boost and a 16-Gy boost in the EORTC phase III "boost no boost" trial (1989-1996). A total of 1616 patients with a microscopically complete resection (according to local pathologists), included in the central pathology review, have been analyzed in this study. Median follow-up was 18.2 years. INTERVENTIONS: No further treatment or 16-Gy boost, after BCS and 50-Gy WBI. MAIN OUTCOMES AND MEASURES: Time to ipsilateral breast tumor recurrence (IBTR) as first event. RESULTS: The 20-year cumulative incidence of IBTR in 1616 patients (160 events observed) was 15% (95% CI, 12%-17%). Young age (P < .001) and presence of ductal carcinoma in situ (DCIS) (HR, 2.15; 95% CI, 1.36-3.38; P = .001) were associated with an increased risk of IBTR in multivariable analysis. The cumulative incidence of IBTR at 20 years was 34% (95% CI, 25%-41%), 14% (95% CI, 10%-18%), and 11% (95% CI, 8%-15%), in patients 40 years or younger, 41 to 50 years and 50 years or older, respectively (P < .001). This incidence was 18% (95% CI, 14%-22%) and 9% (95% CI, 6%-12%) for tumors with and without DCIS (P < .001). High-grade tumors relapsed more frequently early during follow-up but the relative effect of age and presence of DCIS seemed stable over time. The boost reduced the 20-year IBTR incidence from 31% (95% CI, 22%-39%) to 15% (95% CI, 8%-21%) (HR, 0.37; 95% CI, 0.22-0.62; P < .001) in high-risk patients (≤50 years with DCIS present). CONCLUSIONS AND RELEVANCE: The association of high-grade invasive tumor with IBTR diminished during follow-up, while the effect of DCIS adjacent to invasive tumor seemed to remain stable. Therefore, patients with high-grade invasive tumors should be monitored closely, especially in the first 5 years, while additional DCIS is an indication for longer follow-up, emphasizing the importance of long-term trial follow-up to estimate absolute effects accurately. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02295033.

Selective use of post-mastectomy flap irradiation in high-risk breast cancer patients.

The incidence of local recurrence after mastectomy can be reduced by chest wall radiotherapy. However, only a minority of patients are at substantial risk. No UK national guidelines exist for the use of mastectomy flap radiotherapy. This study evaluated a protocol, whereby only high-risk patients were treated with post-mastectomy flap radiotherapy; identified histologically by grade, vascular invasion and nodal status. All women treated by simple mastectomy for invasive breast cancer at the Nottingham Breast Unit from January 1993 to December 1995 were studied (n=292). Postoperative flap radiotherapy was given to 147 high-risk women (50.3%). Median follow-up was 76 months. Overall, 12 women (4.1%) developed a chest wall recurrence; six were single spot recurrences and the remaining six were either multiple spot (n=3) or field change (field change dermal invasion, n=3). The chest wall recurrence rate was 2.7% in those treated with radiotherapy. A low rate of local recurrence has been achieved with selective use of mastectomy flap radiotherapy.

Education and Training Needs in Radiation Oncology in India: Opportunities for Indo-US Collaborations.

PURPOSE: To conduct a survey of radiation oncologists in India, to better understand specific educational needs of radiation oncology in India and define areas of collaboration with US institutions. METHODS AND MATERIALS: A 20-question survey was distributed to members of the Association of Indian Radiation Oncologists and the Indian Brachytherapy Society between November 2013 and May 2014. RESULTS: We received a total of 132 responses. Over 50% of the physicians treat more than 200 patients per day, use 2-dimensional or 3-dimensional treatment planning techniques, and approximately 50% use image guided techniques. For education needs, most respondents agreed that further education in intensity modulated radiation therapy, image guided radiation therapy, stereotactic radiation therapy, biostatistics, and research methods for medical residents would be useful areas of collaboration with institutions in the United States. Other areas of collaboration include developing a structured training module for nursing, physics training, and developing a second-opinion clinic for difficult cases with faculty in the United States. CONCLUSION: Various areas of potential collaboration in radiation oncology education were identified through this survey. These include the following: establishing education programs focused on current technology, facilitating exchange programs for trainees in India to the United States, promoting training in research methods, establishing training modules for physicists and oncology nurses, and creating an Indo-US. Tumor Board. It would require collaboration between the Association of Indian Radiation Oncologists and the American Society for Radiation Oncology to develop these educational initiatives.

Involvement of metformin and AMPK in the radioresponse and prognosis of luminal versus basal-like breast cancer treated with radiotherapy.

Metformin is under evaluation as a potential anticancer agent. Expression of total and phospho(Thr172)-adenosine monophosphate-activated kinase-α (AMPKα and pAMPKα(Thr172) respectively), a main metformin target, was examined in radiotherapy treated breast cancers and metformin's ability to modulate Trx system expression and breast cancer radiosensitivity evaluated in vitro. AMPKα and pAMPKα(Thr172) expression was assessed using a discovery (n=166) and validation cohort (n=609). Metformin's role in regulating radioresponse, and Trx family expression, was examined via clonogenic assays and Western blots. Intracellular reactive oxygen species (ROS) levels, cell cycle progression and apoptosis were assessed by flow cytometry. High AMPKα expression associated with improved local recurrence-free (P=0.019), relapse-free (P=0.016) and breast cancer-specific survival (P=0.000065) and was, from multivariate analysis, an independent prognostic factor from the discovery cohort. From the validation cases AMPKα expression associated with relapse-free and breast cancer-specific survival in luminal breast cancers. Metformin substantially increased radiosensitivity, intracellular ROS levels and reduced Trx expression, in luminal breast cancer cells, but had little effect on basal phenotype cells. In conclusion, high AMPKα expression associates with improved prognosis, especially in luminal breast cancer. Metformin preferentially radiosensitises luminal breast cancer cells, potentially due to alterations to intracellular ROS levels via modulation of Trx family protein expression.

Biological characteristics and clinical outcome of triple negative primary breast cancer in older women - comparison with their younger counterparts.

Triple negative (ER, PgR and HER2 negative) breast cancers (TNBCs) are often considered as a poor prognostic phenotype. There is dearth of evidence showing the prevalence and biological behaviour of TNBCs in older women. This study aimed to analyse their biological characteristics in comparison with a well characterised younger series from a single centre with long term clinical follow-up. Over 37 years (1973-2010), 1,758 older (≥70 years) women with early operable (<5 cm) primary breast cancer were managed in a dedicated clinic and have complete clinical information available. Of these 813 patients underwent primary surgery and 575 had good quality tumour samples available for tissue microarray analysis using indirect immunohistochemistry. A total of 127 patients (22.1%) had TNBCs and full biological analysis of 15 biomarkers was performed. The results were compared with those of their younger (<70 years) counterparts 342 (18.9%) from a previously characterised, consecutive series of primary breast cancer treated in the same unit (1986-1998). The 127 older patients with TNBCs showed lower rates of Ki67 and CK 7/8 positivity and high rates of bcl2 and CK18 positivity when compared with their younger counterparts (p<0.05). There was no significant difference in the long term clinical outcome between the two age groups, despite the fact that 47% of the younger patients had adjuvant chemotherapy, while none in the older cohort received such treatment. EGFR, axillary stage and pathological size showed prognostic significance in older women with TNBCs on univariate analysis. Despite not having received adjuvant chemotherapy, the older series had clinical outcome similar to the younger patients almost half of whom had chemotherapy. This appears to be related to other biomarkers (in addition to ER/PgR/HER2) eg Ki67, bcl2 and cytokeratins which have different expression patterns influencing prognosis.

Strength of ER-positivity in relation to survival in ER-positive breast cancer treated by adjuvant tamoxifen as sole systemic therapy.

AIMS: Oestrogen receptor (ER) positivity has been shown to be a predictive factor for response to endocrine treatment in breast cancer patients. Following breast surgery, adjuvant treatment is allocated according to various parameters (including Nottingham Prognostic Index (NPI), menopausal status and ER status). Patients whose cancer falls in the same NPI range may receive different adjuvant treatment according to ER status. The aim of our study is to assess whether the degree of ER-positivity, as measured immuno-histochemically by H-score (see definition in "Introduction" section) and percentage of ER-stained cells) has an influence on overall survival (OS) and disease-free survival (DFS) and whether this could be used to help determine adjuvant treatment. MATERIALS AND METHODS: A review was undertaken of 563 post-menopausal patients receiving adjuvant tamoxifen and no chemotherapy following surgical resection of histologically proven ER-positive breast cancer. The impact of both H-score and percentage of cells staining for ER was assessed using OS and DFS over a 10-year period. RESULTS: Patients were stratified into 4 groups according to ER H-score, namely those scoring ≤50, 51-100, 100-200, and >200. Ten-year survival was 84% for H-score above 200, 67% for H-score 100-200, 71% for H-score 50-100 and 41% for H-score less than 50 (p<0.001). Ten-year disease-free survival figures were similar, being 84% for H-score above 200, 73% for H-score 100-200, 83% for H-score 51-100 and 28% for H-score less than 50 (p<0.0001). CONCLUSIONS: The data suggests that patients whose tumours only weakly manifest ER (H-score ≤50) fare less well in the long-term than patients whose tumours show more vigorous ER-staining when treated by endocrine therapy as sole systemic adjuvant treatment. This finding is relevant to decisions about adjuvant systemic therapy.

Expression of thioredoxin system and related peroxiredoxin proteins is associated with clinical outcome in radiotherapy treated early stage breast cancer.

BACKGROUND AND PURPOSE: Deregulated redox systems provide cancer cells protection from increased oxidative stress, such as that induced by ionizing radiation. Expression of the thioredoxin system proteins (thioredoxin, thioredoxin reductase and thioredoxin interacting protein) and downstream peroxiredoxins (I-VI), was examined in tumor specimens from early stage breast cancer patients, subsequently treated by breast conserving surgery and locoregional radiotherapy, to determine if redox protein expression is associated with clinical outcome. MATERIAL AND METHODS: Nuclear and cytoplasmic expression was assessed using conventional immunohistochemistry on a tissue microarray of 224 tumors. RESULTS: High expression of cytoplasmic peroxiredoxin-I correlated with a greater risk of local recurrence (p=0.009). When nuclear and cytoplasmic expression patterns were combined, patients with low nuclear but high cytoplasmic expression of peroxiredoxin-I increased significance (p=0.005). Both were independent factors (p=0.006 and 0.003) from multivariate analysis. Associations were obtained between tumor grade and nuclear thioredoxin interacting protein (p=0.01) and with cytoplasmic expression of peroxiredoxin-V (p=0.007) but not with peroxiredoxin-I suggesting that the latter may exert influence via regulation of oxidative stress rather than via altering the tumor phenotype. CONCLUSIONS: Results highlight the potential of using redox protein expression, namely peroxiredoxin-I, to predict clinical outcome and support further studies to validate its usefulness as an independent prognostic, and potentially predictive, marker.

Redox protein expression predicts radiotherapeutic response in early-stage invasive breast cancer patients.

PURPOSE: Early-stage invasive breast cancer patients have commonly undergone breast-conserving surgery and radiotherapy. In a large majority of these patients, the treatment is effective; however, a proportion will develop local recurrence. Deregulated redox systems provide cancer cells protection from increased oxidative stress, such as that induced by ionizing radiation. Therefore, the expression of redox proteins was examined in tumor specimens from this defined cohort to determine whether such expression could predict response. METHODS AND MATERIALS: The nuclear and cytoplasmic expression of nine redox proteins (glutathione, glutathione reductase, glutaredoxin, glutathione peroxidase 1, 3, and 4, and glutathione S-transferase-θ, -π, and -α) was assessed using conventional immunohistochemistry on a tissue microarray of 224 tumors. RESULTS: A high cytoplasmic expression of glutathione S-transferase-θ significantly correlated with a greater risk of local recurrence (p = .008) and, when combined with a low nuclear expression (p = .009), became an independent predictive factor (p = .002) for local recurrence. High cytoplasmic expression of glutathione S-transferase-θ also correlated with a worse overall survival (p = .009). Low nuclear and cytoplasmic expression of glutathione peroxidase 3 (p = .002) correlated with a greater risk of local recurrence and was an independent predictive factor (p = .005). These proteins did not correlate with tumor grade, suggesting their function might be specific to the regulation of oxidative stress rather than alterations of tumor phenotype. Only nuclear (p = .005) and cytoplasmic (p = .001) expression of glutathione peroxidase 4 correlated with the tumor grade. CONCLUSIONS: Our results support the use of redox protein expression, namely glutathione S-transferase-θ and glutathione peroxidase 3, to predict the response to radiotherapy in early-stage breast cancer patients. If incorporated into routine diagnostic tests, they have the potential to aid clinicians in their stratification of patients into more tailored treatment regimens. Future targeted therapies to these systems might improve the efficacy of reactive oxygen species-inducing therapies, such as radiotherapy.

Predictors of the risk of fibrosis at 10 years after breast conserving therapy for early breast cancer: a study based on the EORTC Trial 22881-10882 'boost versus no boost'.

The EORTC 22881-10882 trial in 5178 conservatively treated early breast cancer patients showed that a 16 Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. To investigate predictors for the long-term risk of fibrosis, Cox regression models of the time to moderate or severe fibrosis were developed on a random set of 1797 patients with and 1827 patients without a boost, and validated in the remaining set. The median follow-up was 10.7 years. The risk of fibrosis significantly increased (P<0.01) with increasing maximum whole breast irradiation (WBI) dose and with concomitant chemotherapy, but was independent of age. In the boost arm, the risk further increased (P<0.01) if patients had post-operative breast oedema or haematoma, but it decreased (P<0.01) if WBI was given with >6 MV photons. The c-index was around 0.62. Nomograms with these factors are proposed to forecast the long-term risk of moderate or severe fibrosis.