Comparative effectiveness of ductal carcinoma in situ management and the roles of margins and surgeons

Radiological Underestimation of Tumor Size as a Relevant Risk Factor for Positive Margin Rate in Breast-Conserving Therapy of Pure Ductal Carcinoma In Situ (DCIS)

Background: Radiological underestimation of the actual tumor size is a relevant problem in reaching negative margins in ductal carcinoma in situ (DCIS) associated with microcalcifications in breast-conserving therapy (BCT). The aim of this study is to evaluate whether the radiological underestimation of tumor size has an influence on the histopathological margin status. Methods: Patients who underwent BCT with preoperatively diagnosed pure DCIS were included (pooled analysis of two trials). Multiple factors were analysed regarding radiological underestimation ≥10 mm. Radiological underestimation was defined as mammographic minus histological tumor size in mm. Results: Positive margins occurred in 75 of 189 patients. Radiological underestimation ≥10 mm was an independent influencing factor (OR 5.80; 95%CI 2.55−13.17; p < 0.001). A radiological underestimation was seen in 70 patients. The following parameters were statistically significant associated with underestimation: pleomorphic microcalcifications (OR 3.77; 95%CI 1.27−11.18), clustered distribution patterns (OR 4.26; 95%CI 2.25−8.07), and mammographic tumor sizes ≤20 mm (OR 7.47; 95%CI 3.49−15.99). Only a mammographic tumor size ≤20 mm was an independent risk factor (OR 6.49; 95%CI 2.30−18.26; p < 0.001). Grading, estrogen receptor status, and comedo necrosis did not influence the size estimation. Conclusion: Radiological underestimation is an independent risk factor for positive margins in BCT of DCIS associated with microcalcifications predominantly occurring in mammographic small tumors.

Intraoperative Specimen Ultrasonography: Is It a Reliable Tool for Margin Assessment Following Breast Conservation Surgery for Breast Carcinoma?

BACKGROUND

Assessment of margins after breast conservation surgery is an essential part of management in breast cancer and is important in prognostication of the patient. Various intra-operative techniques like frozen section and imprint cytology are in use to ensure negative margins but have their limitations in the fact that 3D evaluation is not feasible. These lead to false negatives and also are operator dependent. In order to obviate these shortcomings, various centers are using specimen imaging (specimen mammogram and ultrasonography).

AIMS AND OBJECTIVES

1) To evaluate the accuracy of specimen ultrasonography in assessing the margins following breast conservation surgery (BCS). 2) To compare the accuracy of intra-operative specimen ultra-sonography with frozen section for assessment of excision margins following BCS.

MATERIALS AND METHODS

Sixty-two biopsy-proven patients with breast cancer who underwent BCS were included in this prospective study at a tertiary cancer care center. The oriented specimens were evaluated by specimen ultrasonography and later by frozen section. The final histopathology served as the gold standard.

RESULTS

Specimen ultrasonography is found to be superior to frozen section in providing detailed assessment of margins in patients undergoing breast conservation. Specimen ultrasonography was also able to detect additional lesions which might be missed on frozen section, especially the in-situ carcinoma.

[Ductal carcinoma in situ in 2019: Diagnosis, treatment, prognosis]

Ductal carcinoma in situ (DCIS) currently represents up to 15% of the newly diagnosed breast cancers, and are almost always detected by microcalcifications. Global prognosis is good (3% of 15-year specific mortality) but invasive local recurrences (LR) can lead to metastasis in 12-15% of the cases. Breast conserving surgery with whole breast irradiation is the main treatment (reducing LR by 50%), but mastectomy (with or without reconstruction) is performed in about 30% of the cases due to wide lesion size and/or multicentricity. The role of tamoxifen remains unclear. Axillary dissection is needless but sentinel node biopsy is proposed in case of micro-invasion suspicion (large lesions with high grade). The main factors of LR are young age (≤40 years) incomplete excision, and high nuclear grade with comedonecrosis. Several studies on "therapeutic descalation" are still ongoing in order to identify the "low risk" DCIS (about 10% of the cases) in which radiotherapy could be safely omitted.

Time-varying risks of second events following a DCIS diagnosis in the population-based Vermont DCIS cohort

PURPOSE

Long-term disease-free survival patterns following surgical, radiation, and endocrine therapy treatments for ductal carcinoma in situ (DCIS) are not well characterized in general US practice.

METHODS

We identified 1252 women diagnosed with DCIS in Vermont during 1994-2012 using data from the Vermont Breast Cancer Surveillance System, a statewide registry of breast imaging and pathology records. Poisson regression and Cox regression with time-varying hazards were used to evaluate disease-free survival among self-selected treatment groups.

RESULTS

With 7.8 years median follow-up, 192 cases experienced a second breast cancer diagnosis. For women treated with breast-conserving surgery (BCS) alone, the annual rate of second events decreased from 3.1% (95% CI 2.2-4.2%) during follow-up years 1-5 to 1.7% (95% CI 0.7-3.5%) after 10 years. In contrast, the annual rate of second events among women treated with BCS plus adjuvant radiation therapy increased from 1.8% (95% CI 1.1-2.6%) during years 1-5 to 2.8% (95% CI 1.6-4.7%) after 10 years (P < 0.05 for difference in trend compared to BCS alone). Annual rates of second events also increased over time among women treated with BCS plus adjuvant radiation and endocrine therapy (P = 0.01 for difference in trend compared to BCS alone). The rate of contralateral events increased after 10 years for all groups with adjuvant treatments. The rate of second events did not vary over time among women who underwent ipsilateral mastectomy (P = 0.62).

CONCLUSIONS

Long-term risk of a second event after DCIS varies over time in a manner dependent on initial treatment.

Evaluation of intraductal delivery of poly(ethylene glycol)-doxorubicin conjugate nanocarriers for the treatment of ductal carcinoma in situ (DCIS)-like lesions in rats

Ductal carcinoma in situ is the most commonly diagnosed early stage breast cancer. The efficacy of intraductally delivered poly(ethylene glycol)-doxorubicin (PEG-DOX) nanocarriers, composed of one or more DOX conjugated to various PEG polymers, was investigated in an orthotopic ductal carcinoma in situ-like rat model. In vitro cytotoxicity was evaluated against 13762 Mat B III cells using MTT assay. The orthotopic model was developed by inoculating cancer cells into mammary ducts of female Fischer 344 retired breeder rats. The ductal retention and in vivo antitumour efficacy of two of the six nanocarriers (5 kDa PEG-DOX and 40 kDa PEG-(DOX)4) were investigated based on in vitro results. Mammary retention of DOX and PEG-DOX nanocarriers was quantified using in vivo imaging. Histopathologic effects of DOX and PEG-DOX nanocarriers on mammary ductal structure were also investigated. Cytotoxicities of small linear PEG-DOX nanocarriers (5 and 10 kDa) were not different from DOX whereas larger PEG-DOX nanocarriers showed reduced potency. The order of mammary retention was 40 kDa PEG-(DOX)4 > 5 kDa PEG-DOX >> DOX, in normal and tumour-bearing rats. Intraductally administered PEG-DOX nanocarriers and DOX were effective in reducing tumour incidence and increasing survival rate, with no significant differences found among the three treatment groups. However, nanocarriers administered intravenously at the same doses were not effective, and intraductally administered free DOX caused severe local toxicity. Intraductal administration of PEG-DOX nanocarriers is effective and less toxic than that of free DOX, as well as IV DOX/PEG-DOX. Furthermore, PEG-DOX nanocarriers demonstrate the added benefit of prolonging DOX ductal retention, which would necessitate less frequent dosing.

Comparative Effectiveness of Surgical Options for Patients with Ductal Carcinoma In Situ: An Instrumental Variable Approach

CONTEXT

Many patients with ductal carcinoma in situ (DCIS) receive treatment that is too extensive.

OBJECTIVE

To take a holistic approach in comparing the effectiveness in cancer prevention between mastectomy and breast-conserving surgery (BCS) for patients with DCIS.

DESIGN

Female Kaiser Permanente Southern California members who underwent surgery for treatment of single primary DCIS from 2004 to 2014 were identified by the Kaiser Permanente Southern California cancer registry and HealthConnect database.

METHOD

Two-stage residual inclusion with the surgeon's preference of surgical procedure type as the instrumental variable was used to examine the effect of surgical choice on DCIS recurrence, breast cancer progression, and other cancer progression. Traditional Cox proportional hazards models were used for comparison.

RESULTS

Of qualified subjects, 72.2% underwent BCS and 27.8% underwent mastectomy. Patients were likelier to receive BCS if their surgeon preferred to perform BCS in the past 5 years (odds ratio = 1.02, 95% confidence interval = 1.02-1.03). Although traditional Cox proportional hazards models suggested an association between BCS and higher risk of DCIS recurrence, no significant effect was observed when we adjusted for endogeneity. Neither model showed significant differences between mastectomy and BCS in progression of any cancer.

CONCLUSION

No significant benefit was observed with a more aggressive surgical procedure in preventing DCIS recurrence or cancer progression in a diverse population. Many patients with DCIS could benefit from BCS with preservation of their body image. Breast conservation followed-up with cancer surveillance is a rational approach to ensure affordable, effective care for patients with DCIS.

Subsequent risk of ipsilateral and contralateral invasive breast cancer after treatment for ductal carcinoma in situ: incidence and the effect of radiotherapy in a population-based cohort of 10,090 women

PURPOSE

To assess the effect of different treatment strategies on the risk of subsequent invasive breast cancer (IBC) in women diagnosed with ductal carcinoma in situ (DCIS).

METHODS

Up to 15-year cumulative incidences of ipsilateral IBC (iIBC) and contralateral IBC (cIBC) were assessed among a population-based cohort of 10,090 women treated for DCIS in the Netherlands between 1989 and 2004. Multivariable Cox regression analyses were used to evaluate associations of treatment with iIBC risk.

RESULTS

Fifteen years after DCIS diagnosis, cumulative incidence of iIBC was 1.9 % after mastectomy, 8.8 % after BCS+RT, and 15.4 % after BCS alone. Patients treated with BCS alone had a higher iIBC risk than those treated with BCS+RT during the first 5 years after treatment. This difference was less pronounced for patients <50 years [hazard ratio (HR) 2.11, 95 % confidence interval (CI) 1.35-3.29 for women <50, and HR 4.44, 95 % CI 3.11-6.36 for women ≥50, P interaction  < 0.0001]. Beyond 5 years of follow-up, iIBC risk did not differ between patients treated with BCS+RT or BCS alone for women <50. Cumulative incidence of cIBC at 15 years was 6.4 %, compared to 3.4 % in the general population.

CONCLUSIONS

We report an interaction of treatment with age and follow-up period on iIBC risk, indicating that the benefit of RT seems to be smaller among younger women, and stressing the importance of clinical studies with long follow-up. Finally, the low cIBC risk does not justify contralateral prophylactic mastectomies for many women with unilateral DCIS.

Importance of Surgical Margin Status in Ductal Carcinoma In Situ

BACKGROUND

The purpose of the study was to identify the effect of final surgical margin (SM) status and re-excision on outcomes in patients with ductal carcinoma in situ (DCIS) who underwent breast conservation therapy (BCT).

PATIENTS AND METHODS

The study population consisted of women diagnosed with DCIS who underwent BCT between 1989 and 2014. All women received adjuvant whole breast radiation and a boost. The primary end point was local control (LC). Final SMs were defined according to margin width: negative SM was defined as > 2 mm, close SM was defined as > 0 to ≤ 2 mm, and a positive SM was defined as tumor on ink. The Cox proportional hazards model was used to determine predictors of outcomes on multivariable analysis. Actuarial incidence of LC was estimated using the Kaplan-Meier method.

RESULTS

A total of 498 patients were included; 400 patients had a final negative SM, 87 had a close SM, and 11 had a positive SM. A total of 172 patients received adjuvant hormonal therapy, 265 patients required ≥ 1 re-excision. Patients with positive or close SMs were more likely to receive a radiation dose > 60 Gy (P < .001) and undergo re-excision (P < .01). The 10-year LC rates were not significantly different between patients with a negative (93.5%), close (91.8%), or positive (100%) SM (P = .57). There was no difference in LC in patients who underwent re-excision for initial close or positive SMs (P = .55).

CONCLUSION

This single-institution experience showed that risks of local recurrence remain poorly characterized. Re-excision and whole breast radiation with boost resulted in excellent LC for women with DCIS. Trials aimed at personalized deintensified local therapy are warranted.

Influence of surgical margins on the outcome of breast cancer patients: a retrospective analysis

OBJECTIVE

Breast-conserving surgery has become the preferred treatment for early breast cancer. Yet the question of what constitutes a 'safe margin', in terms of impact on patient outcome, remains unanswered. Our aim was to address this knowledge gap by determining the prevalence of positive and narrow margins after breast-conserving surgery, and evaluating how margin status impacted local recurrence and overall survival.

MATERIALS AND METHODS

We collected data about all women who underwent breast-conserving cancer surgery in our department between 2002 and 2011, focusing on patient and tumor characteristics, the distance from the tumor to the surgical margin, therapies administered, and outcome (measured in terms of local recurrence and overall survival). Data were analyzed by R (version 3.0.1), considering p < 0.05 as significant. Multivariate analyses were also performed.

RESULTS

Of 1,192 women who received breast-conserving surgery, 264 were considered for widening; 111 of these patients had positive margins and 153 narrow (where narrow was defined as less than 5 mm). Widening was performed for 38 % of these patients (99/264) and mastectomy for 27 % (70/264), while 36 % (95/264) had no further surgery and were simply followed-up. Our multivariate analysis confirmed that local tumor recurrence and overall survival were not significantly influenced by margin status, either at initial surgery, or (for those patients with initially positive margins) at secondary margin-widening surgery. However, the following were found to be significantly correlated with local recurrence: tumor multifocality, high expression of Ki-67/Mib-1, comedo-like necrosis, and non-axillary lymph node positivity (p < 0.05).

CONCLUSIONS

We found the status of resection margins and the management of infiltrated or narrow margins to have no significant influence on local tumor recurrence rates or on overall patient survival. Instead, biological factors connected with tumor aggressiveness seem to play the most important role in breast cancer prognosis, independent of surgical radicality.

Survival Comparisons for Breast Conserving Surgery and Mastectomy Revisited: Community Experience and the Role of Radiation Therapy

OBJECTIVES

Evidence suggests superiority of breast conserving surgery (BCS) plus radiation over mastectomy alone for treatment of early stage breast cancer. Whether the superiority of BCS plus radiation is related to the surgical approach itself or to the addition of adjuvant radiation therapy following BCS remains unclear.

MATERIALS AND METHODS

We conducted a retrospective cohort study of women with breast cancer diagnosed from 1994-2012. Data regarding patient and tumor characteristics and treatment specifics were captured electronically. Kaplan-Meier survival analyses were performed with inverse probability of treatment weighting to reduce selection bias effects in surgical assignment.

RESULTS

Data from 5335 women were included, of which two-thirds had BCS and one-third had mastectomy. Surgical decision trends changed over time with more women undergoing mastectomy in recent years. Women who underwent BCS versus mastectomy differed significantly regarding age, cancer stage/grade, adjuvant radiation, chemotherapy, and endocrine treatment. Overall survival was similar for BCS and mastectomy. When BCS plus radiation was compared to mastectomy alone, 3-, 5-, and 10-year overall survival was 96.5% vs 93.4%, 92.9% vs 88.3% and 80.9% vs 67.2%, respectively.

CONCLUSION

These analyses suggest that survival benefit is not related only to the surgery itself, but that the prognostic advantage of BCS plus radiation over mastectomy may also be related to the addition of adjuvant radiation therapy. This conclusion requires prospective confirmation in randomized trials.

Endoscopy-assisted breast-conserving surgery for breast cancer patients

Breast-conserving surgery (BCS) combined with postoperative radiotherapy is a standard therapy for early-stage breast cancer patients. In addition, recent developments in oncoplastic surgery have improved cosmetic outcomes and patient satisfaction. Therefore, a breast surgeon's current role in BCS is not only to perform a curative resection of cancerous lesions with adequate surgical margins, but also to preserve the shape and appearance of the treated breast. Endoscopy-assisted breast-conserving surgery (EBCS), which has the advantage of a less noticeable scar, was developed more than ten years ago. Recently, some clinical studies have reported the feasibility, oncological outcomes, aesthetic outcomes, and patient satisfaction of EBCS. Herein, we will review the EBCS clinical studies that have been conducted so far and discuss current issues regarding this operative method.

Polarization-sensitive multimodal imaging for detecting breast cancer

Intraoperative delineation of breast cancer is a significant problem in surgical oncology. A reliable method for demarcation of malignant breast tissue during surgery would reduce the re-excision rate due to positive margins. We present a novel method of identifying breast cancer margins using combined dye-enhanced wide-field fluorescence polarization imaging for en face cancer margins and polarization-sensitive (PS) optical coherence tomography (OCT) for cross-sectional evaluation. Tumor specimens were collected following breast surgery, stained with methylene blue, and imaged. Wide-field fluorescence polarization images were excited at 640 nm and registered between 660 and 750 nm. Standard and PS OCT images were acquired using a commercial 1,310-nm swept-source system. The imaging results were validated against histopathology. Statistically significant higher fluorescence polarization of cancer as compared with both normal and fibrocystic tumor tissue was measured in all the samples. Fluorescence polarization delineated lateral breast cancer margins with contrast superior to that provided by OCT. However, OCT complemented fluorescence polarization imaging by facilitating cross-sectional inspection of tissue. PS OCT yielded higher contrast between cancer and connective tissue, as compared with standard OCT. Combined PS OCT and fluorescence polarization imaging shows promise for intraoperative delineation of breast cancer.

MarginProbe: intraoperative margin assessment during breast conserving surgery by using radiofrequency spectroscopy

In breast conserving surgery, the tumor should be removed with a clean margin, a rim of healthy tissue surrounding. Failure to achieve clean margins in the initial surgery results in a re-excision procedure. Re-excision rates are reported as being 11-46% for invasive carcinoma and ductal carcinoma in situ (DCIS). Re-excisions can have negative consequences such as increased postoperative infections, negative impact on cosmesis, patient anxiety and increased medical costs. Therefore, the surgical margin of invasive and intraductal (DCIS) breast tissue is a subject of intense discussion. Different options for intraoperative assessment are available, but all in all, they are unsatisfying. Frozen section margin examination is possible but is time consuming and restricted to the assessment of invasive carcinoma. In the case of DCIS, there is no procedure for intraoperative margin assessment. Thus, a solution for efficient intraoperative surgical margin assessment is needed. For this purpose, an innovative, real-time, intraoperative margin-assessment device (MarginProbe, Dune Medical Devices, Caesarea, Israel) was designed, and recent published clinical data reported a reduction of re-excisions by more than 50%.

The relationship between extent of thyroid cancer surgery and use of radioactive iodine

By linking surgeon surveys to the National Cancer Database, we found that surgeons' tendency to perform more extensive thyroid resection is associated with greater use of radioactive iodine for stage I thyroid cancer.

OBJECTIVE

To determine the relationships between surgeon recommendations for extent of resection and radioactive iodine use in low-risk thyroid cancer.

BACKGROUND

There has been an increase in thyroid cancer treatment intensity; the relationship between extent of resection and medical treatment with radioactive iodine remains unknown.

METHODS

We randomly surveyed thyroid surgeons affiliated with 368 hospitals with Commission on Cancer-accredited cancer programs. Survey responses were linked to the National Cancer Database. The relationship between extent of resection and the proportion of the American Joint Committee on Cancer stage I well-differentiated thyroid cancer patients treated with radioactive iodine after total thyroidectomy was assessed with multivariable weighted regression, controlling for hospital and surgeon characteristics.

RESULTS

The survey response rate was 70% (560/804). Surgeons who recommend total thyroidectomy over lobectomy for subcentimeter unifocal thyroid cancer were significantly more likely to recommend prophylactic central lymph node dissection for thyroid cancer regardless of tumor size (P < 0.001). They were also more likely to favor radioactive iodine in patients with intrathyroidal unifocal cancer ≤1 cm (P = 0.001), 1.1-2 cm (P = 0.004), as well as intrathyroidal multifocal cancer ≤1 cm (P = 0.004). In multivariable analysis, high hospital case volume, fewer surgeon years of experience, general surgery specialty, and preference for more extensive resection were independently associated with greater hospital-level use of radioactive iodine for stage I disease.

CONCLUSIONS

In addition to surgeon experience and specialty, surgeons' tendency to perform more extensive thyroid resection is associated with greater use of radioactive iodine for stage I thyroid cancer.

Disease-free survival by treatment after a DCIS diagnosis in a population-based cohort study

Randomized trials have demonstrated the efficacy of radiation and tamoxifen in reducing risk of second events after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS), but the comparative effectiveness of mastectomy, BCS, and adjuvant treatments have not been established in community practice. We examined disease-free survival (DFS) among 1,676 DCIS cases diagnosed during 1995-2006 in the population-based Wisconsin In Situ Cohort study. Information on patient and tumor characteristics, treatments, and second breast cancer events were collected via a comprehensive review of data from patient interviews, the statewide cancer registry, and pathology reports. Breast cancer DFS was evaluated according to treatment while adjusting for patient and tumor characteristics. After an average of 7.1 years of follow-up, 143 second breast cancer events occurred. Overall 5-year DFS was similar among women treated with ipsilateral mastectomy (95.6 %; 95 % CI 93.5-97.0) compared to women treated with BCS and radiation (94.8 %; 95 % CI 92.8-96.1), though women receiving BCS without radiation experienced poorer overall DFS (87.0 %; 95 % CI 80.6-91.5). Women treated with tamoxifen in addition to BCS and radiation had a similar risk of a second breast event, although the hazard ratio (HR) suggested a potential benefit (0.70, 95% CI 0.41-1.19). Women treated with BCS, radiation, and tamoxifen had comparable risk of a second event as those treated with ipsilateral mastectomy (HR = 1.20; 95 % CI 0.71-2.02). In this population-based sample, the use of BCS with radiation and tamoxifen resulted in high DFS rates comparable to those achieved by ipsilateral mastectomy.

Intra-operative radiological margins assessment in conservative treatment for non-palpable DCIS: correlation to pathological examination and re-excision rate

What constitutes an adequate surgical margin in partial mastectomy is still controversial: intra-operative specimen radiogram is commonly used during partial mastectomy for nonpalpable lesions in order verify the adequacy of the resection but what margin is to be considered “adequate” is still debatable.

An intraoperative specimen mammogram was performed during all consecutive conservative resections for nonpalpable DCIS and a 15-mm radiological margin was considered “adequate”. Margins were pathologically assessed and classified as “negative”, “close” or “positive” and the rate of margin involvement constitued the main outcome of the study.

Among 272 conservative interventions, 80.51% had negative margins at final pathology, 3.31% had close margins and 16.18% had positive margins.

An intraoperative “adequate” margin of 15 mm as defined on intraoperative specimen mammogram granted a high rate of histologically negative margin at primary surgery; this finding was paralleled by confirmation of the treatment as conservative in 95% of cases.

Factors associated with the frequency of initial total mastectomy: results of a multi-institutional study

BACKGROUND

Several previous studies have reported conflicting data on recent trends in use of initial total mastectomy (TM); the factors that contribute to TM variation are not entirely clear. Using a multi-institution database, we analyzed how practice, patient, and tumor characteristics contributed to variation in TM for invasive breast cancer.

STUDY DESIGN

We collected detailed clinical and pathologic data about breast cancer diagnosis, initial, and subsequent breast cancer operations performed on all female patients from 4 participating institutions from 2003 to 2008. We limited this analysis to 2,384 incident cases of invasive breast cancer, stages I to III, and excluded patients with clinical indications for mastectomy. Predictors of initial TM were identified with univariate analyses and random effects multivariable logistic regression models.

RESULTS

Initial TM was performed on 397 (16.7%) eligible patients. Use of preoperative MRI more than doubled the rate of TM (odds ratio [OR] = 2.44; 95% CI, 1.58-3.77; p < 0.0001). Increasing tumor size, high nuclear grade, and age were also associated with increased rates of initial TM. Differences by age and ethnicity were observed, and significant variation in the frequency of TM was seen at the individual surgeon level (p < 0.001). Our results were similar when restricted to tumors <20 mm.

CONCLUSIONS

We identified factors associated with initial TM, including preoperative MRI and individual surgeon, that contribute to the current debate about variation in use of TM for the management of breast cancer. Additional evaluation of patient understanding of surgical options and outcomes in breast cancer and the impact of the surgeon provider is warranted.

Network meta-analysis of margin threshold for women with ductal carcinoma in situ

BACKGROUND

Negative margins are associated with reduced risk of ipsilateral breast tumor recurrence (IBTR) for women with ductal carcinoma in situ (DCIS) treated with breast-conserving surgery (BCS). However, there is no consensus about the best minimum margin width.

METHODS

We searched the PubMed database for studies of DCIS published in English between January 1970 and July 2010 and examined the relationship between IBTR and margin status after BCS for DCIS. Women with DCIS were stratified into two groups, BCS with or without radiotherapy. We used frequentist and Bayesian approaches to estimate the odds ratios (OR) of IBTR for groups with negative margins and positive margins. We further examined specific margin thresholds using mixed treatment comparisons and meta-regression techniques. All statistical tests were two-sided.

RESULTS

We identified 21 studies published in 24 articles. A total of 1066 IBTR events occurred in 7564 patients, including BCS alone (565 IBTR events in 3098 patients) and BCS with radiotherapy (501 IBTR events in 4466 patients). Compared with positive margins, negative margins were associated with reduced risk of IBTR in patients with radiotherapy (OR = 0.46, 95% credible interval [CrI] = 0.35 to 0.59), and in patients without radiotherapy (OR = 0.34, 95% CrI = 0.24 to 0.47). Compared with patients with positive margins, the risk of IBTR for patients with negative margins was smaller (negative margin >0 mm, OR = 0.45, 95% CrI = 0.38 to 0.53; >2 mm, OR = 0.38, 95% CrI = 0.28 to 0.51; >5 mm, OR = 0.55, 95% CrI = 0.15 to 1.30; and >10 mm, OR = 0.17, 95% CrI = 0.12 to 0.24). Compared with a negative margin greater than 2 mm, a negative margin of at least 10 mm was associated with a lower risk of IBTR (OR = 0.46, 95% CrI = 0.29 to 0.69). We found a probability of .96 that a negative margin threshold greater than 10 mm is the best option compared with other margin thresholds.

CONCLUSIONS

Negative surgical margins should be obtained for DCIS patients after BCS regardless of radiotherapy. Within cosmetic constraint, surgeons should attempt to achieve negative margins as wide as possible in their first attempt. More studies are needed to understand whether margin thresholds greater than 10 mm are warranted.

Comparison of whole genome amplification methods for analysis of DNA extracted from microdissected early breast lesions in formalin-fixed paraffin-embedded tissue

To understand cancer progression, it is desirable to study the earliest stages of its development, which are often microscopic lesions. Array comparative genomic hybridization (aCGH) is a valuable high-throughput molecular approach for discovering DNA copy number changes; however, it requires a relatively large amount of DNA, which is difficult to obtain from microdissected lesions. Whole genome amplification (WGA) methods were developed to increase DNA quantity; however their reproducibility, fidelity, and suitability for formalin-fixed paraffin-embedded (FFPE) samples are questioned. Using aCGH analysis, we compared two widely used approaches for WGA: single cell comparative genomic hybridization protocol (SCOMP) and degenerate oligonucleotide primed PCR (DOP-PCR). Cancer cell line and microdissected FFPE breast cancer DNA samples were amplified by the two WGA methods and subjected to aCGH. The genomic profiles of amplified DNA were compared with those of non-amplified controls by four analytic methods and validated by quantitative PCR (Q-PCR). We found that SCOMP-amplified samples had close similarity to non-amplified controls with concordance rates close to those of reference tests, while DOP-amplified samples had a statistically significant amount of changes. SCOMP is able to amplify small amounts of DNA extracted from FFPE samples and provides quality of aCGH data similar to non-amplified samples.

Ductal carcinoma in situ, and the influence of the mode of detection, population characteristics, and other risk factors

Approximately 25% of breast cancers in the United States are diagnosed as ductal carcinoma in situ (DCIS). Rates of DCIS have risen from 5.8 per 100,000 women in the 1970s to 32.5 per 100,000 in 2004. This pattern is generally attributed to increased use of screening mammography. DCIS is a major risk factor for invasive breast cancer, and considerable controversy remains about whether DCIS should be considered a direct precursor of invasive breast cancer. There is, however, a general consensus that DCIS represents an intermediate step between normal breast tissue and invasive breast cancer. Although the majority of major risk factors are similar for DCIS and invasive breast cancer, prognostic factors including estrogen and progesterone receptor status and HER2 positivity are less well studied but look to have similar value in both cases. The use of postdiagnostic MRI, sentinel lymph node biopsy, surgery, radiation, and endocrine therapy are all evolving as evidence from randomized and observational studies continues to accumulate. Treatment of DCIS requires a balance between risk of overtreatment and undertreatment. Ongoing studies are focusing on whether partial-breast irradiation is as effective as whole-breast irradiation and whether treatment with endocrine therapies can reduce the likelihood of either invasive breast cancer or DCIS recurrence. In general, treatment decisions should take into account the likelihood that an apparent case of DCIS could harbor foci of invasive disease.

High-frequency ultrasound for intraoperative margin assessments in breast conservation surgery: a feasibility study

Background

In addition to breast imaging, ultrasound offers the potential for characterizing and distinguishing between benign and malignant breast tissues due to their different microstructures and material properties. The aim of this study was to determine if high-frequency ultrasound (20-80 MHz) can provide pathology sensitive measurements for the ex vivo detection of cancer in margins during breast conservation surgery.

Methods

Ultrasonic tests were performed on resected margins and other tissues obtained from 17 patients, resulting in 34 specimens that were classified into 15 pathology categories. Pulse-echo and through-transmission measurements were acquired from a total of 57 sites on the specimens using two single-element 50-MHz transducers. Ultrasonic attenuation and sound speed were obtained from time-domain waveforms. The waveforms were further processed with fast Fourier transforms to provide ultrasonic spectra and cepstra. The ultrasonic measurements and pathology types were analyzed for correlations. The specimens were additionally re-classified into five pathology types to determine specificity and sensitivity values.

Results

The density of peaks in the ultrasonic spectra, a measure of spectral structure, showed significantly higher values for carcinomas and precancerous pathologies such as atypical ductal hyperplasia than for normal tissue. The slopes of the cepstra for non-malignant pathologies displayed significantly greater values that differentiated them from the normal and malignant tissues. The attenuation coefficients were sensitive to fat necrosis, fibroadenoma, and invasive lobular carcinoma. Specificities and sensitivities for differentiating pathologies from normal tissue were 100% and 86% for lobular carcinomas, 100% and 74% for ductal carcinomas, 80% and 82% for benign pathologies, and 80% and 100% for fat necrosis and adenomas. Specificities and sensitivities were also determined for differentiating each pathology type from the other four using a multivariate analysis. The results yielded specificities and sensitivities of 85% and 86% for lobular carcinomas, 85% and 74% for ductal carcinomas, 100% and 61% for benign pathologies, 84% and 100% for fat necrosis and adenomas, and 98% and 80% for normal tissue.

Conclusions

Results from high-frequency ultrasonic measurements of human breast tissue specimens indicate that characteristics in the ultrasonic attenuation, spectra, and cepstra can be used to differentiate between normal, benign, and malignant breast pathologies.

Disease-free probability after the first primary ductal carcinoma in situ of the breast: a comparison between African-American and White-American women

Compelling evidence about the differences in the biology and behavior of invasive breast cancer between African-American (AA) and White-American (WA) women motivate inquiry into comparing the clinicopathology of non-invasive breast cancer (ductal carcinoma in situ, DCIS). AA and WA women diagnosed with their first primary DCIS between 1990 and 1999 were identified from the institutional tumor registry. Data on method of presentation, treatment, and patient characteristics were retrieved from electronic medical records. Patients were followed up through the medical records until the diagnosis of a subsequent cancer or the last day of contact with the institution. A total of 100 (29.6%) AAs and 236 (70.4%) WAs with the mean age of 60 (SD ± 13) and 57 (SD ± 12), respectively, contributed to this study. DCIS was detected during routine screening mammography for 81% (n = 81) of AAs and 88.4% (n = 206) of WAs (P = 0.073). Differences in the distributions of grade, margin status, necrosis, or treatment modalities were not statistically significant between AAs and WAs. Analysis of competing risks Cox proportional hazard multivariate modeling yielded a significant 8-year cumulative risk of a second cancer for AAs but only in the ipsilateral breast (HR = 3.96, 95% CI 1.42-11.04, P = 0.01). Despite comparable clinical presentation and treatment, 8 years after the initial treatment, AAs experienced a higher risk of second breast cancer in ipsilateral but not in the contralateral breast. The observed excess risk of a second cancer in the ipsilateral breast may suggest of intrinsic differences in the biology of cancer.

Structural estimates of treatment effects on outcomes using retrospective data: an application to ductal carcinoma in situ

Analysis of observational cohort data is subject to bias from unobservable risk selection. The authors compared econometric models and treatment effectiveness estimates using the linked Surveillance, Epidemiology, and End Results (SEER)-Medicare claims data for women diagnosed with ductal carcinoma in situ. Treatment effectiveness estimates for mastectomy and breast-conserving surgery (BCS) with or without radiotherapy were compared using three different models: simultaneous-equations model, discrete-time survival model with unobserved heterogeneity (frailty), and proportional hazards model. Overall trends in disease-free survival (DFS), or time to first subsequent breast event, by treatment are similar regardless of the model, with mastectomy yielding the highest DFS over 8 years of follow-up, followed by BCS with radiotherapy, and then BCS alone. Absolute rates and direction of bias varied substantially by treatment strategy. DFS was underestimated by single-equation and frailty models compared with the simultaneous-equations model and randomized controlled trial results for BCS with radiotherapy and overestimated for BCS alone.