Role of Sentinel Lymph Node Biopsy in Ductal Carcinoma-in-situ Treated by Mastectomy

Radiological and pathological predictors of post-operative upstaging of breast ductal carcinoma in situ (DCIS) to invasive ductal carcinoma and lymph-nodes metastasis; a potential algorithm for node surgical de-escalation

BACKGROUND/AIM

Ductal carcinoma in situ is considered a local disease with no metastatic potential, thus sentinel lymph node biopsy (SLNB) may be deemed an overtreatment. SLNB should be reserved for patients with invasive cancer, even though the risk of upstaging rises to 25 %. We aimed to identify clinicopathological predictors of post-operative upstaging in invasive carcinoma.

METHODS

We retrospectively analyzed patients with a pre-operative diagnosis of DCIS subjected to breast surgery between January 2017 to December 2021, and evaluated at the Breast Unit of PTV (Policlinico Tor Vergata, Rome).

RESULTS

Out of 267 patients diagnosed with DCIS, 33(12.4 %) received a diagnosis upstaging and 9(3.37 %) patients presented with sentinel lymph node (SLN) metastasis. In multivariate analysis, grade 3 tumor (OR 1.9; 95 % CI 1.2-5.6), dense nodule at mammography (OR 1.3; 95 % CI 1.1-2.6) and presence of a solid nodule at ultrasonography (OR 1.5; 95 % CI 1.2-2.6) were independent upstaging predictors. Differently, the independent predictors for SLNB metastasis were: upstaging (OR 2.1.; 95 % CI 1.2-4.6; p = 0.0079) and age between 40 and 60yrs (OR 1.4; 95 % CI 1.4-2.7; p = 0.027). All 9 patients with SLN metastasis received a diagnosis upstaging and were aged between 40 and 60 years old.

CONCLUSION

We identified pre-operative independent predictors of upstaging to invasive ductal carcinoma. The combined use of different predictors in an algorithm for surgical treatments of DCIS could reduce the numbers of unnecessary SLNB.

Can We Successfully De-Escalate Axillary Surgery in Women Aged ≥ 70 Years with Ductal Carcinoma in Situ or Early-Stage Breast Cancer Undergoing Mastectomy?

BACKGROUND

Omission of sentinel lymph node biopsy (SLNB) in older women with clinically node-negative, hormone receptor-positive (HR+) early-stage breast cancer undergoing lumpectomy is accepted, given established low rates of regional recurrence. The safety of omitting SLNB in women undergoing mastectomy is unknown and may differ depending on extent of breast disease and variation in radiotherapy use.

PATIENTS AND METHODS

From 2006 to 2018, 123 cTis and 328 cT1-2 HR+/HER2- tumors from 410 women aged ≥ 70 years who underwent mastectomy and SLNB were included (41 bilateral cases). The rate of nodal positivity and effect of nodal positivity on adjuvant therapy use were examined.

RESULTS

Median age was 74 years; 21% of patients had positive sentinel lymph nodes, 7% had micrometastases, and 14% had macrometastases. Of cases of cTis tumors, 31% were upstaged to invasive carcinoma; 1% had macrometastases. Fewer cases of cT1 than cT2 tumors had macrometastases [13% (26/200) versus 29% (37/128); p < 0.001]. Eight percent of patients with pT1 tumors (18/228) and 27% of patients with pT2 tumors (30/113) received chemotherapy. Most patients with pT1, pN1 disease (78%; 25/32) did not receive chemotherapy. Rates of locoregional recurrence were similar between patients with cT1 or cT2 tumors with and without nodal metastases (median follow-up, 4.5 years).

CONCLUSIONS

Women aged ≥ 70 years with cTis and cT1N0 HR+/HER2- tumors who underwent mastectomy had low rates of nodal positivity, similar to rates reported for lumpectomy. Given this and the RxPONDER results, omission of SLNB may be considered, as findings are unlikely to alter adjuvant therapy recommendations.

Clinicopathological predictors of postoperative upstaging to invasive ductal carcinoma (IDC) in patients preoperatively diagnosed with ductal carcinoma in situ (DCIS): a multi-institutional retrospective cohort study

Background

We conducted a prospective study with the intention to omit surgery for patients with ductal carcinoma in situ (DCIS) of the breast. We aimed to identify clinicopathological predictors of postoperative upstaging to invasive ductal carcinoma (IDC) in patients preoperatively diagnosed with DCIS.

Patients and methods

We retrospectively analyzed patients with DCIS diagnosed through biopsy between April 1, 2010 and December 31, 2014, from 16 institutions. Clinical, radiological, and histological variables were collected from medical records.

Results

We identified 2,293 patients diagnosed with DCIS through biopsy, including 1,663 DCIS (72.5%) cases and 630 IDC (27.5%) cases. In multivariate analysis, the presence of a palpable mass (odds ratio [OR] 1.8; 95% confidence interval [CI] 1.2–2.6), mammography findings (≥ category 4; OR 1.8; 95% CI 1.2–2.6), mass formations on ultrasonography (OR 1.8; 95% CI 1.2–2.5), and tumor size on MRI (> 20 mm; OR 1.7; 95% CI 1.2–2.4) were independent predictors of IDC. Among patients with a tumor size on MRI of ≤ 20 mm, the possibility of postoperative upstaging to IDC was 22.1%. Among the 258 patients with non-palpable mass, nuclear grade 1/2, and positive for estrogen receptor, the possibility was 18.1%, even if the upper limit of the tumor size on MRI was raised to ≤ 40 mm.

Conclusion

We identified four independent predictive factors of upstaging to IDC after surgery among patients with DCIS diagnosed by biopsy. The combined use of various predictors of IDC reduces the possibility of postoperative upstaging to IDC, even if the tumor size on MRI is larger than 20 mm.

Sentinel lymph node biopsy may be unnecessary for ductal carcinoma in situ of the breast that is small and diagnosed by preoperative biopsy

BACKGROUND

Current guidelines do not recommend that sentinel lymph node biopsy is routinely performed for ductal carcinoma in situ; thus, indications for sentinel lymph node biopsy in patients with ductal carcinoma in situ remain controversial. In this study, we investigated whether sentinel lymph node biopsy can be safely omitted when ductal carcinoma in situ has been diagnosed by preoperative biopsy.

METHODS

We retrospectively analysed sentinel lymph node metastasis rates and upstaging to invasive cancer in surgical specimens, performed receiver operating characteristic analysis for ductal carcinoma in situ lesion size and assessed correlations with preoperative clinicopathological factors of 277 patients with ductal carcinoma in situ diagnosed by preoperative biopsy at our institution.

RESULTS

Among 277 patients with sentinel lymph node biopsy, six (2.2%) had sentinel lymph node metastasis. All six were upstaged to invasive cancer by pathological examination of surgical specimens. In total, 69 patients (24.9%) were upstaged to invasive cancer. The mean size of ductal carcinoma in situ lesions on preoperative imaging was significantly larger for the 69 upstaged patients (50.0 mm) than for the non-upstaged patients (34.4 mm; P < 0.0001). Of the 277 patients with sentinel lymph node biopsy, 117 (42.2%) had preoperative ductal carcinoma in situ lesions <31.8 mm, which was identified as the optimal cut-off size by receiver operating characteristic analysis. Of these 117 patients, 96 (82.1%, 95% confidence interval: 73.9-88.5%) could be safely omitted from sentinel lymph node biopsy because all of them remained as ductal carcinoma in situ and had negative sentinel lymph nodes at surgery.

CONCLUSIONS

Size of ductal carcinoma in situ lesions on preoperative diagnostic imaging is a predictor of diagnosis of invasive cancer on pathological examination of surgical specimens. Sentinel lymph node biopsy may be unnecessary in ductal carcinoma in situ diagnosed by preoperative biopsy in patients with small lesions.

Predictors of invasive disease in patients preoperatively diagnosed with ductal carcinoma without stromal invasion, with breast magnetic resonance imaging (MRI) and ultrasound (US)

BACKGROUND

A preoperative diagnosis of ductal carcinoma in situ (DCIS) is sometimes upstaged to invasive disease postoperatively. Our objective was to clarify the predictive factors of invasive disease using preoperative imaging and to investigate the positive ratio of sentinel lymph nodes (SLN) and the incidence of invasive disease.

METHODS

The subjects were 402 patients with preoperatively diagnosed ductal carcinoma without stromal invasion who underwent breast surgery with concomitant SLN surgery in January 2007 to December 2016. Of the 306 included patients, all 306 patients underwent preoperative MRI and US assessment. Outcomes were analyzed for significance using univariate and multivariate analyses.

RESULTS

Of the 306 patients, 115 (37.6%) had invasive disease and 191 (62.4%) had DCIS only. Of the 115 patients with invasive disease, 5 (4.4%) and 4 (3.5%) had macro- and micrometastases in SLN. On the other hand, of the 191 patients with DCIS, only 1 (0.5%) had a micrometastasis. Predictors of invasive disease in the univariate analysis included having a palpable mass, were varied by biopsy method, having a US hypoechoic mass, MRI enhancement, or MRI large enhanced lesion; the size of the mass enhancement ≥ 1.1 cm or a spread of non-mass enhancement ≥ 3.1 cm (P = 0.003). Predictors of invasive disease in the multivariate analysis included US hypoechoic mass and MRI large enhanced lesion.

CONCLUSION

We need to perform SLN biopsy for preoperatively diagnosed DCIS when patients have predictors of invasive disease, but SLN biopsy will no longer be essential for patients when they have no predictors of invasive disease.

Sentinel lymph node positivity in patients undergoing mastectomies for ductal carcinoma in situ (DCIS)

Current guidelines recommend sentinel lymph node biopsy (SLNB) for patients undergoing mastectomy for a preoperative diagnosis of ductal carcinoma in situ (DCIS). We examined the factors associated with sentinel lymph node positivity for patients undergoing mastectomy for a diagnosis of DCIS on preoperative core biopsy (PCB). The Institutional Breast Cancer Database was queried for patients with PCB demonstrating pure DCIS followed by mastectomy and SLNB from 2010 to 2018. Patients were divided according to final pathology (DCIS or invasive cancer). Clinico-pathologic variables were analyzed using Pearson's chi-squared, Wilcoxon Rank-Sum and logistic regression. Of 3145 patients, 168(5%) had pure DCIS on PCB and underwent mastectomy with SLNB. On final mastectomy pathology, 120(71%) patients had DCIS with 0 positive sentinel lymph nodes (PSLNs) and 48(29%) patients had invasive carcinoma with 5(10%) cases of ≥1 PSLNs. Factors positively associated with upstaging to invasive cancer in univariate analysis included age (P = .0289), palpability (P < .0001), extent of disease on imaging (P = .0121), mass on preoperative imaging (P = .0003), multifocality (P = .0231) and multicentricity (P = .0395). In multivariate analysis, palpability (P = .0080), extent of disease on imaging (P = .0074) and mass on preoperative imaging (P = .0245) remained significant (Table 2). In a subset of patients undergoing mastectomy for DCIS with limited disease on preoperative evaluation, SLNB may be omitted as the risk of upstaging is low. However, patients who present with clinical findings of palpability, large extent of disease on imaging and mass on preoperative imaging have a meaningful risk of upstaging to invasive cancer, and SLNB remains important for management.

Predictive factors of axillary positive sentinel lymph node biopsy in extended ductal carcinoma in situ treated by simple mastectomy at once

BACKGROUND

The incidence of positive sentinel lymph node biopsy (SLNB) in ductal carcinoma in situ (DCIS) ranged from 0 to 14%. The main hypothesis would be the presence of an invasive contingent on the final histology. The objective was to identify predictive factors of sentinel lymph node positivity in the management of extended ductal carcinoma in situ treated by simple mastectomy.

METHODS

This was a retrospective study carried out at the Lorraine Cancer Institute from January 2003 to December 2017. Women with DCIS on core-needle biopsy whose management consisted of simple mastectomy and SLNB procedure were included.

RESULTS

188 patients were analyzed. Preoperatively, 18 patients (9.6%) had DCIS with microinvasion, while the others had pure DCIS. Eight patients (4.2%) had positive sentinel lymph node biopsy, the majority of which were single micrometastases. Predictive factor of node invasion was microinvasion on biopsy (p<0.01). Only in cases of pure DCIS, the percentage of positive SLNB was reduced to 2.9%. Invasive carcinoma was found in the majority of patients with positive axillary SLNB procedure (75%, n=6), compared to 16.7% (n=30) without SLNB involvement (p<0.01).

CONCLUSIONS

The low rate of positive sentinel node biopsy in pure ductal carcinoma in situ suggests that in the absence of microinvasion, the sentinel procedure would seem less appropriate. New techniques for identifying sentinel lymph node biopsy could report axillary staging after definitive histologic results.

Upstaging to invasive ductal carcinoma after mastectomy for ductal carcinoma in situ: predictive factors and role of sentinel lymph node biopsy

BACKGROUND

The aim of this study was to investigate preoperative factors associated with ductal carcinoma in situ (DCIS) upstaged to invasive ductal carcinoma (IDC) and sentinel lymph node (SLN) status in patients who underwent mastectomy for a preoperative diagnosis of DCIS.

METHODS

The medical records of 220 patients who underwent mastectomy for a preoperative diagnosis of DCIS were retrospectively reviewed.

RESULTS

Fifty-one (22.6%) of 226 lesions were upgraded to IDC after mastectomy. Preoperative factors associated with upstaging to IDC included patient-reported signs and symptoms, a clinically palpable mass, ultrasound findings classified as category 4 or 5, the ultrasound appearance of a mass or widely distributed non-mass abnormality (NMA), and a high Ki67 index. The prevalence of SLN macrometastasis was 0.9%. IDC was diagnosed for 10.9% of lesions of a preoperative ultrasound category of 0-3, 13.0% of those with no mass or NMA detected by ultrasonography, and 14.1% of lesions preoperatively diagnosed by methods other than core needle biopsy (CNB). Of those lesions, none was associated with SLN metastasis.

CONCLUSIONS

Routinely performing SLN biopsy for patients undergoing mastectomy for a preoperative diagnosis of DCIS is overtreatment, because the prevalence of SLN metastasis was low. SLN biopsy can be omitted for most patients. In particular, we suggest omitting SLN biopsy for patients who have lesions of ultrasound category 0-3, who have neither a mass nor NMA detected by ultrasound, or whose initial diagnosis was made based on a specimen obtained by methods other than CNB.

Is sentinel lymph node biopsy indicated in patients with a diagnosis of ductal carcinoma in situ? A systematic literature review and meta-analysis

BACKGROUND

Recent discussion has suggested that some cases of ductal carcinoma in situ (DCIS) with high risk of invasive disease may require sentinel lymph node biopsy (SLNB).

METHODS

Systematic literature review identified 48 studies (9,803 DCIS patients who underwent SLNB). Separate analyses for patients diagnosed preoperatively by core sampling and patients diagnosed postoperatively by specimen pathology were conducted to determine the percentage of patients with axillary nodal involvement. Patient factors were analyzed for associations with risk of nodal involvement.

RESULTS

The mean percentage of positive SLNBs was higher in the preoperative group (5.95% vs 3.02%; P = .0201). Meta-regression analysis showed a direct association with tumor size (P = .0333) and grade (P = .00839) but not median age nor tumor upstage rate.

CONCLUSIONS

The SLNB should be routinely considered in patients with large (>2 cm) high-grade DCIS after a careful multidisciplinary discussion. In the context of breast conserving surgery, the SLNB is not routinely indicated for low- and intermediate-grade DCIS, high-grade DCIS smaller than 2 cm, or pure DCIS diagnosed by definitive surgical excision.

Do LORIS Trial Eligibility Criteria Identify a Ductal Carcinoma In Situ Patient Population at Low Risk of Upgrade to Invasive Carcinoma?

BACKGROUND

The Surgery Versus Active Monitoring for Low-Risk DCIS (LORIS) trial is studying the safety of monitoring core-biopsy diagnosed low-risk ductal carcinoma in situ (DCIS) without excision. We sought to determine the incidence and characteristics of synchronous invasive carcinoma found in LORIS-eligible women who underwent excision, as this knowledge is essential in assessing the safety of observation alone.

METHODS

Women meeting LORIS eligibility criteria (age ≥46 years, screen-detected calcifications, non-high-grade DCIS diagnosed by core biopsy, absence of nipple discharge, or strong family history of breast cancer) who underwent surgical excision from 2009 to 2012 were identified. Histologic findings of excision specimens were reviewed.

RESULTS

Overall, 296 LORIS-eligible cases were identified; 58 (20 %) had invasive carcinoma on final pathology (90 % invasive ductal, 78 % >1 mm in size, 21 % high grade, 3 % triple negative, 9 % HER2 amplified). Of these, 18 (31 %) were pT1b or larger and 3 (5 %) were pN1. Among eligible upgraded cases, 90 % received radiation, 89 % received endocrine therapy, and 18 % were recommended chemotherapy. Women upgraded to invasive carcinoma were more likely to have intermediate-grade DCIS on core biopsy and to have undergone mastectomy.

CONCLUSIONS

Among LORIS-eligible women, 20 % had invasive carcinoma at surgical excision that was heterogeneous in grade, size, and receptor status. Information gained from surgical excision influenced receipt of adjuvant radiation and endocrine therapy in most patients, and indicated benefit from chemotherapy in 18 % of patients. Surgical excision is warranted until additional risk stratification is available to identify a cohort of DCIS patients at lower risk for clinically significant synchronous invasive carcinoma.

Is Sentinel Lymph Node Biopsy Indicated at Completion Mastectomy for Ductal Carcinoma In Situ?

BACKGROUND

Sentinel lymph node biopsy (SLNB) is recommended when mastectomy is performed for ductal carcinoma in situ (DCIS). The role of SLNB for women with DCIS who undergo mastectomy following one or more attempts at breast-conserving surgery (BCS) is uncertain. We examined the upgrade rate and SLNB yield in women who converted to mastectomy after one or more attempts at BCS for DCIS.

METHODS

All patients who underwent one or more attempts at BCS prior to conversion to mastectomy with SLNB for DCIS were identified. Margin status as the indication for mastectomy was confirmed, and comparisons were made between patients with/without upgrade on final pathology.

RESULTS

From February 2006 to November 2012, a total of 233 patients underwent completion mastectomy following one or more attempts at BCS for positive/close margins (median age 50 years; range 34-84). The median number of BCS attempts was 1 (range 1-4). Overall, 20 (9 %) patients were upgraded on final pathology; 15 (6 %) stage I, and 5 (3 %) stage II (three micrometastasis, two macrometastasis). In two of five cases with a positive SLN, invasive carcinoma was not identified in the mastectomy specimen. The only factor associated with any upgrade was the presence of micropapillary DCIS (80 vs. 55 %, with and without upgrade; p = 0.03).

CONCLUSION

In this cohort of patients with DCIS who converted to mastectomy for positive/close margins after one or more attempts at BCS, 18 (8 %) would have required second-stage axillary surgery had an SLNB not been performed, and in two (1 %) patients, the SLN provided the only evidence of invasion. These findings support the recommendation for SLNB at the time of completion mastectomy.

Is Sentinel Lymph Node Dissection Warranted for Patients with a Diagnosis of Ductal Carcinoma In Situ?

BACKGROUND

Positive sentinel lymph node (SLN) findings in ductal carcinoma in situ (DCIS) range from 1 to 22 % but have unknown biologic significance. This study sought to identify predictors of positive SLNs and to assess their clinical significance for patients with an initial diagnosis of DCIS.

METHODS

The study identified 1234 patients with an initial diagnosis of DCIS who underwent SLN dissection (SLND) at our institution from 1997 through 2011. Positive SLN findings were categorized as isolated tumor cells (ITCs) (≤0.2 mm), micrometastases (>0.2-2 mm), or macrometastases (>2 mm). Predictors of positive SLNs were analyzed, and survival outcomes were examined.

RESULTS

Positive SLN findings were identified in 132 patients (10.7 %): 66 patients with ITCs (5.4 %), 36 patients with micrometastases (2.9 %), and 30 patients with macrometastases (2.4 %). Upstaging to microinvasive (n = 68, 5.5 %) or invasive (n = 259, 21.0 %) cancer occurred for 327 patients (26.5 %). Factors predicting positive SLNs included diagnosis by excisional biopsy (odds ratio [OR] 1.90; P = 0.007), papillary histology (OR 1.77; P = 0.006), DCIS larger than 2 cm (OR 1.55; P = 0.030), more than three interventions before SLND (4 interventions: OR 2.04; P = 0.022; ≥5 interventions: OR 3.87; P < 0.001), and occult invasion (microinvasive: OR 3.44; P = 0.001; invasive: OR 6.21; P < 0.001). The median follow-up period was 61.7 months. Patients who had pure DCIS with and without positive SLNs had equivalent survival rates (100.0 vs 99.7 %; P = 0.679). Patients with occult invasion and positive SLNs had the worst survival rate (91.7 %; P < 0.001).

CONCLUSIONS

Occult invasion and more than three total interventions were the strongest predictors of positive SLN findings in patients with an initial diagnosis of DCIS. This supports the theory of benign mechanical transport of breast epithelial cells. Except for patients at high risk for invasive disease, routine use of SLND in DCIS is not warranted.

Preoperatively diagnosed ductal carcinoma in situ: risk prediction of invasion and effects on axillary management

BACKGROUND

Preoperatively diagnosed ductal carcinoma in situ (DCIS) has the potential to have occult invasion. The predictors of invasive carcinoma underestimation in patients with DCIS diagnosed by preoperative percutaneous biopsy were identified and the effects of underestimation on axillary management were evaluated.

METHODS

Medical records of 280 patients preoperatively diagnosed as DCIS who underwent surgery were retrospectively analyzed. The patients were divided into non-invasive and invasive carcinoma groups according to the final pathological diagnosis. Risk predictors of invasive carcinoma underestimation and axillary lymph node (ALN) metastasis were analyzed. The axillary status estimated by pathological diagnosis and one-step nucleic acid amplification (OSNA) assay was evaluated.

RESULTS

The presence of an invasive carcinoma was overlooked in 104 (37.1 %) patients. A clinically palpable mass was an independent risk predictor of invasive carcinoma underestimation by multivariate analysis. There was no risk predictor of ALN metastasis. No ALN metastasis was seen in non-invasive carcinoma group. Six (6.2 %) patients in invasive carcinoma group had macro- or micrometastasis in sentinel lymph nodes (SLNs). Non-SLN metastasis was observed in 3 patients of them. Fourteen patients with only isolated tumor cells (ITCs) or only OSNA-positive SLNs had no metastasis in non-SLNs.

CONCLUSIONS

SLN biopsy and, if necessary, subsequent ALN dissection (ALND) should be performed in patients with DCIS who have a risk predictor of underestimation. ALND can be avoided in patients who have histologically negative or ITC-positive SLNs, regardless of the presence of invasion on final pathological diagnosis.

The Role of Sentinel Lymph Node Biopsy and Factors Associated with Invasion in Extensive DCIS of the Breast Treated by Mastectomy: The Cinnamome Prospective Multicenter Study

Background

When invasive components are discovered at mastectomy for vacuum-assisted biopsy (VAB)-diagnosed ductal carcinoma in situ (DCIS), the only option available is axillary lymph node dissection (ALND). The primary aim of this prospective multicenter trial was to determine the benefit of performing upfront sentinel lymph node (SLN) biopsy for these patients. The secondary aim was to determine DCIS factors associated with microinvasion or invasion.

Methods

The SLN procedure was performed during mastectomy, and for positive SLN an ALND was performed during the same intervention. A tissue microarray containing DCIS lesions from the mastectomy specimens was subsequently performed.

Results

From May 2008 to December 2010, 228 patients were enrolled from 14 French cancer centers, including 192 eligible patients with pure DCIS on VAB and successful SLN procedures. ALND was avoided for 51 [67 %; 95 % confidence interval (CI), 56–77 %] of all the patients who had microinvasive DCIS or DCIS associated with invasive carcinoma at mastectomy and a negative SLN. Of the 192 patients, 76 (39 %) with VAB-diagnosed DCIS were upgraded after mastectomy to micro (n = 20) or invasive disease (n = 56). The rate of positive SLN for patients with DCIS on VAB was 14 %. High nuclear grade of DCIS was associated with greater risk of microinvasion and invasion, and HER2-amplified DCIS was associated with greater risk of invasion.

Conclusions

Underestimation of invasive components is high when DCIS is diagnosed by VAB in patients undergoing mastectomy. Upfront SLN for patients with VAB-diagnosed extensive DCIS avoids unnecessary ALND for two-thirds of patients with micro or invasive disease on mastectomy.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-015-4476-5) contains supplementary material, which is available to authorized users.

Incidence and prediction of invasive disease and nodal metastasis in preoperatively diagnosed ductal carcinoma in situ

For breast cancer patients with a preoperative diagnosis of ductal carcinoma in situ (DCIS), sentinel lymph node (SN) biopsy has been proposed as an axillary staging procedure in selected patients with a higher likelihood of having occult invasive lesions. With detailed histological examination of primary tumors and molecular whole-node analysis of SNs, we aimed to validate whether this selective application accurately identifies patients with SN metastasis. The subjects were 336 patients with a preoperative needle-biopsy diagnosis of DCIS who underwent SN biopsy using the one-step nucleic acid amplification assay in the period 2009–2011. The incidence and preoperative predictors of upstaging to invasive disease on final pathology and SN metastasis, and their correlation, were investigated. Of the 336 patients, 113 (33.6%) had invasive disease, and 6 (1.8%) and 17 (5.0%) had macro- and micrometastasis in axillary nodes respectively. Of the 113 patients with invasive disease, 4 (3.5%) and 9 (8.0%) had macro- and micrometastasis. Predictors of invasive disease included palpability, mammographic mass, and calcifications (spread >20 mm), and intraductal solid structure, but no predictor was found for SN metastasis. Therefore, even though occult invasive disease was found at final pathology, most of the patients had no metastasis or only micrometastasis in axillary nodes. Predictors of invasive disease and SN metastasis were not completely consistent, so the selective SN biopsy for patients with a higher risk of invasive disease may not accurately identify those with SN metastasis. More accurate application of SN biopsy is required for patients with a preoperative diagnosis of DCIS.

Underestimation of invasive lesions in patients with ductal carcinoma in situ of the breast diagnosed by ultrasound-guided biopsy: a comparison between patients with and without HER2/neu overexpression

PURPOSE

To determine the rate of underestimation of ductal carcinoma in situ (DCIS) diagnosed at imaging-guided biopsy and to analyze its association with HER2/neu oncogene, an important biomarker in assessing the tumour aggressiveness and guiding hormone therapy for breast cancer.

METHODS

We retrospectively reviewed 162 patients with DCIS diagnosed by imaging-guided core needle biopsy between January 2008 and March 2013. All of these patients received surgical excision, and in 25, the diagnosis was upgraded to invasive breast cancer. In this study, we examined the ultrasound, mammographic features and histopathological results for each patient, and compared these parameters between those with and without HER2/neu overexpression.

RESULTS

Of the 162 DCIS lesions, 110 (67.9%) overexpressed HER2/neu. Nineteen patients with HER2/neu overexpressing DCIS (n=19/110, 17.3%) were upgraded after surgery to a diagnosis of invasive breast cancer. In this group, the upgrade rate was highest in patients with a dilated mammary duct pattern (42.1%, n=8/19, p=0.02) and the presence of abnormal axillary nodes (40.0%, n=12/30, p<0.01) at ultrasound and was significantly associated with comedo tumour type on pathology.

CONCLUSIONS

Biopsy may underestimate the invasive component in DCIS patients. Sonographic findings of dilated mammary ducts and presence of abnormal axillary lymph nodes may help predicting the invasive components and possibly driving more targeted biopsy procedures.

Incidence of and risk factors for sentinel lymph node metastasis in patients with a postoperative diagnosis of ductal carcinoma in situ

Background

Positive sentinel lymph nodes (SLNs) are found in up to 13 per cent of women with a preoperative diagnosis of ductal carcinoma in situ (DCIS) of the breast and in up to 4 per cent of those with a postoperative diagnosis. This retrospective national register study investigated the incidence of positive SLNs in women with a postoperative diagnosis of DCIS, and the value of additional tumour sectioning to identify occult tumour invasion.

Methods

All surgical patients with a final histopathological diagnosis of pure DCIS registered in the Swedish national breast cancer register in 2008 and 2009 were eligible. Additional sectioning was performed on archived primary tumour tissue from women with SLN metastasis (including cases of isolated tumour cells) and matched SLN-negative control patients with the aim of detecting occult invasion.

Results

SLN tumour deposits were reported in 11 of 753 women who had SLN biopsy (macrometastases, 2; micrometastases, 3; isolated tumour cells, 6), resulting in a SLN positivity rate of 0·7 per cent (5 of 753). Occult invasion was found in one (9 per cent) of these 11 patients and in two (10 per cent) of 21 control patients. No risk factors for SLN metastasis were identified.

Conclusion

SLN positivity is rare in women with a histopathological diagnosis of pure DCIS. Additional primary tumour assessment may reveal occult invasion in both SLN metastasis-positive and -negative patients. The value of performing SLN biopsy in the setting of a preoperative diagnosis of DCIS was limited, and current Swedish practice should therefore be questioned.

Sentinel Lymph Node Biopsy Should Be Included with the Initial Surgery for High-Risk Ductal Carcinoma-In-Situ

Background. A proportion of those diagnosed preoperatively with ductal carcinoma-in-situ (DCIS) will be histologically upgraded to invasive carcinoma. Repeat surgery for sentinel lymph node (SLN) biopsy will be required if it had not been included with the initial surgery. We reviewed the outcome of SLN biopsy performed with the initial surgery based on a preoperative diagnosis of DCIS and aimed to identify patients at risk of histological upgrade. Methods. Retrospective review of 294 consecutive female patients diagnosed with DCIS was performed at our institute from January 1, 2001, to December 31, 2008. Results. Of the 294 patients, 132 (44.9%) underwent SLN biopsy together with the initial surgery. The SLN was positive for metastases in 5 patients, all of whom had tumours that were histologically upgraded. Histological upgrade also occurred in 43 of the 127 patients (33.9%) in whom the SLN was negative for metastases. On multivariate analysis, histological upgrade was more likely if a mass was detected on mammogram, if the preoperative diagnosis was obtained with core biopsy and if microinvasion was reported in the biopsy. Conclusion. Patients in whom a preoperative diagnosis of DCIS is likely to be upgraded to invasive carcinoma will benefit from SLN biopsy being performed with the initial surgery.

Development and evaluation of a prediction model for underestimated invasive breast cancer in women with ductal carcinoma in situ at stereotactic large core needle biopsy

BACKGROUND

We aimed to develop a multivariable model for prediction of underestimated invasiveness in women with ductal carcinoma in situ at stereotactic large core needle biopsy, that can be used to select patients for sentinel node biopsy at primary surgery.

METHODS

From the literature, we selected potential preoperative predictors of underestimated invasive breast cancer. Data of patients with nonpalpable breast lesions who were diagnosed with ductal carcinoma in situ at stereotactic large core needle biopsy, drawn from the prospective COBRA (Core Biopsy after RAdiological localization) and COBRA2000 cohort studies, were used to fit the multivariable model and assess its overall performance, discrimination, and calibration.

RESULTS

348 women with large core needle biopsy-proven ductal carcinoma in situ were available for analysis. In 100 (28.7%) patients invasive carcinoma was found at subsequent surgery. Nine predictors were included in the model. In the multivariable analysis, the predictors with the strongest association were lesion size (OR 1.12 per cm, 95% CI 0.98-1.28), number of cores retrieved at biopsy (OR per core 0.87, 95% CI 0.75-1.01), presence of lobular cancerization (OR 5.29, 95% CI 1.25-26.77), and microinvasion (OR 3.75, 95% CI 1.42-9.87). The overall performance of the multivariable model was poor with an explained variation of 9% (Nagelkerke's R(2)), mediocre discrimination with area under the receiver operating characteristic curve of 0.66 (95% confidence interval 0.58-0.73), and fairly good calibration.

CONCLUSION

The evaluation of our multivariable prediction model in a large, clinically representative study population proves that routine clinical and pathological variables are not suitable to select patients with large core needle biopsy-proven ductal carcinoma in situ for sentinel node biopsy during primary surgery.

MR features to suggest microinvasive ductal carcinoma of the breast: can it be differentiated from pure DCIS?

BACKGROUND

Morphologic and kinetic characteristics of breast lesions are regarded as a major criterion for their differential diagnosis in dynamic magnetic resonance imaging (MRI). However, there have not been well-reported MRI findings of microinvasive ductal carcinoma.

PURPOSE

To evaluate MRI characteristics of microinvasive ductal carcinoma of the breast and to compare MRI findings in patients with microinvasive ductal carcinoma and pure ductal carcinoma in situ (DCIS).

MATERIAL AND METHODS

Eighty-one patients with pathologically confirmed microinvasive ductal carcinomas (n = 37) or pure DCIS (n = 44) were included in this study. The MRI findings were analyzed without knowledge of the pathologic and conventional imaging findings. For all the lesions detected on MRI, morphologic and kinetic analyses were performed according to the Breast Imaging Reporting and Data System. For the non-mass lesions, the presence of clustered ring enhancement was also analyzed. Statistical analyses were performed using Student's t test, χ(2) test, and Fisher's exact test.

RESULTS

In total 35 cases of microinvasive ductal carcinoma and 39 cases of DCIS were detected on MRI. The most common and dominant MRI findings of microinvasive ductal carcinoma and DCIS were non-mass lesions with heterogeneous enhancement. However, the spiculated margin of the mass-type lesion (P = 0.022), the segmental distribution (P = 0.023), and clustered ring enhancement (P = 0.006) of the non-mass-type lesion, and the enhancement kinetics showing strong initial enhancement (P = 0.004) with subsequent wash-out (P = 0.001) were significantly more frequent in microinvasive ductal carcinoma than in DCIS.

CONCLUSION

Non-mass lesions with segmental distribution, heterogeneous enhancement, and strong initial enhancement with a wash-out curve were the dominant MRI findings of microinvasive ductal carcinoma. Compared with DCIS, microinvasive ductal carcinoma showed more suspicious imaging characteristics. For the non-mass lesions, clustered ring enhancement was also a characteristic finding of microinvasion on MRI.

Utility of intraoperative frozen section examination of sentinel lymph nodes in ductal carcinoma in situ of the breast

BACKGROUND

Intraoperative frozen section (IFS) examination of sentinel lymph nodes (SLN) is useful in selecting patients with invasive breast cancer for immediate axillary lymph node dissection. However, whether IFS evaluation of the SLNs in ductal carcinoma in situ (DCIS) of the breast has any value has not been previously assessed.

METHODS

Clinicopathologic data from patients with DCIS who underwent resection with SLN biopsy (2004-2010) were collected to assess the sensitivity, specificity, and accuracy of IFS, and its impact on axillary management.

RESULTS

A total of 267 patients with DCIS underwent resection with SLN biopsy and IFS evaluation. Preoperative pathology was DCIS (n = 231), DCIS with microinvasion (n = 24), and DCIS with other lesions (n = 12). Fifty-two (19.5%) patients had invasive breast cancer on final pathology. SLN metastases were identified in 13 (4.8%) patients; however, only 4 (1.5%) were IFS positive. IFS examination was negative in 263 (98.5%) patients. Among patients with SLN metastases, the most common pattern of metastases was either micrometastasis (n = 6) or immunohistochemistry-positive individual tumor cells (n = 4), whereas 3 patients had a macrometastasis. IFS examination was falsely negative in 9 of these 13 patients for a false-negative rate of 69.3%, and a sensitivity and specificity of 31% and 100% respectively. Nine of the 13 patients underwent axillary lymph node dissection and only 1 patient had further axillary metastasis.

CONCLUSIONS

SLN metastases in DCIS is rare and most commonly involves SLN micrometastasis or immunohistochemistry-positive individual tumor cells. SLN IFS evaluation in DCIS has a low yield and sensitivity, and can be safely omitted to reduce operative duration and cost.

Prediction of underestimated invasiveness in patients with ductal carcinoma in situ of the breast on percutaneous biopsy as rationale for recommending concurrent sentinel lymph node biopsy

AIM

To develop a model to predict invasion and improve the indication of concurrent sentinel lymph node biopsy (SLNB) for patients with ductal carcinoma in situ (DCIS) on minimally invasive biopsy.

METHODS

We evaluated the data of 205 patients with DCIS in minimally invasive biopsy specimens. Clinical, radiological and histological variables were assessed in order to identify predictors of invasive carcinoma in final pathology using logistic regression analyses. We developed and retrospectively tested an algorithm to indicate concurrent SLNB.

RESULTS

Invasiveness was underestimated in 18.0% (37 of 205). Univariate analysis revealed the following significant risk factors: lesion palpability, a mass lesion on ultrasound, the presence of a mammographically detectable mass, architectural distortion or density, a BI-RADS score of 5, a lesion diameter ≥50 mm, and ≥50% of histologically affected ducts. With a palpable mass, which remained the only independent predictor of invasion after multivariate adjustment, and the presence of at least three of the remaining five risk factors, the probability of invasion was 56.0%. If the prediction model had been used to indicate SLNB 9.8% (20 of 205) of patients could have been benefited (i.e. spared unnecessary or correctly recommended concurrent SLNB) compared to the factual performed SLNB procedures. Those patients with pure DCIS treated with breast conserving surgery (BCS) benefited most with a relative risk reduction of nearly 50% for unnecessary SLNB.

CONCLUSION

The prediction model could rationally guide an informed discussion about risks and benefits of concurrent SLNB in patients with DCIS on minimally invasive biopsy.

Utilization of sentinel lymph node biopsy in patients with ductal carcinoma in situ undergoing mastectomy

BACKGROUND

Current guidelines suggest consideration of sentinel lymph node biopsy (SLNB) for patients with ductal carcinoma in situ (DCIS) undergoing mastectomy. Our objective was to identify factors influencing the utilization of SLNB in this population.

METHODS

We used the Surveillance Epidemiology and End Results database to identify all women with breast DCIS treated with mastectomy from 2000 to 2008. We excluded patients without histologic confirmation, those diagnosed at autopsy, those who had axillary lymph node dissections performed without a preceding SLNB, and those for whom the status of SLNB was unknown. We used multivariate logistic regression reporting odds ratios (OR) and 95% confidence intervals (CI) to evaluate the relationship of patient- and tumor-related factors to the likelihood of undergoing SLNB.

RESULTS

Of 20,177 patients, 51% did not receive SLNB. Factors associated with a decreased likelihood of receiving a SLNB included advancing age (OR 0.66; 95% CI 0.62-0.71), Asian (OR 0.75; CI 0.68-0.83) or Hispanic (OR 0.84; 95% CI 0.74-0.96) race/ethnicity, and history of prior non-breast (OR 0.57; 95% CI 0.53-0.61). Factors associated with an increased likelihood of receiving a SLNB included treatment in the east (OR 1.28; 95% CI 1.17-1.4), intermediate (OR 1.25; 95% CI 1.11-1.41), high (OR 1.84; 95% CI 1.62-2.08) grade tumors, treatment after the year 2000, and DCIS size 2-5 cm (OR 1.54; 95% CI 1.42-1.68) and >5 cm (OR 2.43; 95% CI 2.16-2.75).

CONCLUSIONS

SLNB is increasingly utilized in patients undergoing mastectomy for DCIS, but disparities in usage remain. Efforts at improving rates of SLNB in this population are warranted.

Sentinel Lymph Node Biopsy in Pure DCIS: Is It Necessary?

Introduction. Sentinel lymph node biopsy (SLNB) in patients with pure ductal carcinoma in situ (DCIS) has been a matter of debate due to very low rate of axillary metastases. We therefore aimed to identify factors in a single institutional series to select patients who may benefit from SLNB. Material and Methods. Patients, diagnosed with pure DCIS (n = 63) between July 2000 and March 2011, were reviewed. All the sentinel lymph nodes were examined by serial sectioning (50 μm) of the entire lymph node and H&E staining, and by cytokeratin immunostaining in suspicious cases. Results. Median age was 51 (range, 30-79). Of 63 patients, 40 cases (63.5%) with pure DCIS underwent SLN, and 2 of them had a positive SLN (5%). In both 2 cases with SLN metastases, only one sentinel lymph node was involved with tumor cells. Patients who underwent SLNB were more likely to have a tumor size >30 mm or DCIS with intermediate and high nuclear grade or a mastectomy in univariate and multivariate analyses. Conclusion. In our series, we found a slightly higher rate of SLNB positivity in patients with pure DCIS than the large series reported elsewhere. This may either be due to the meticulous examination of SLNs by serial sectioning technique or due to our patient selection criteria or both.

Ductal carcinoma in situ at core-needle biopsy: meta-analysis of underestimation and predictors of invasive breast cancer

PURPOSE

To perform a meta-analysis to report pooled estimates for underestimation of invasive breast cancer (where core-needle biopsy [CNB] shows ductal carcinoma in situ [DCIS] and excision histologic examination shows invasive breast cancer) and to identify preoperative variables that predict invasive breast cancer.

MATERIALS AND METHODS

Studies were identified by searching MEDLINE and were included if they provided data on DCIS underestimates (overall and according to preoperative variables). Study-specific and pooled percentages for DCIS underestimates were calculated. By using meta-regression (random effects logistic modeling) the association between each study-level preoperative variable and understaged invasive breast cancer was investigated.

RESULTS

Fifty-two studies that included 7350 cases of DCIS with findings at excision histologic examination as the reference standard met the eligibility criteria and were included. There were 1736 underestimates (invasive breast cancer at excision); the random-effects pooled estimate was 25.9% (95% confidence interval: 22.5%, 29.5%). Preoperative variables that showed significant univariate association with higher underestimation included the use of a 14-gauge automated device (vs 11-gauge vacuum-assisted biopsy, P = .006), high-grade lesion at CNB (vs non-high grade lesion, P < .001), lesion size larger than 20 mm at imaging (vs lesions ≤ 20 mm, P < .001), Breast Imaging Reporting and Data System (BI-RADS) score of 4 or 5 (vs BI-RADS score of 3, P for trend = .005), mammographic mass (vs calcification only, P < .001), and palpability (P < .001).

CONCLUSION

About one in four DCIS diagnoses at CNB represent understaged invasive breast cancer. Preoperative variables significantly associated with understaging include biopsy device and guidance method, size, grade, mammographic features, and palpability.

HER2-positive status is an independent predictor for coexisting invasion of ductal carcinoma in situ of the breast presenting extensive DCIS component

DCIS of the breast with coexisting invasion is commonly seen, and no consensus on any biomarker capable of discriminating this subgroup has been reached yet. We retrospectively examined the receptor status and the histological grade in Chinese DCIS patients to identify any independent predictor in order to discriminate a subgroup with coexisting invasion from pure DCIS patients. A consecutive Chinese DCIS patient cohort registered at a single institution was included for ER, PR, and HER2 status, as well as for evaluation of the histological grade. Patients with invasion foci >1cm in diameter were excluded. The HER2 gene amplification status was further examined by FISH when the IHC result was HER2 (2+). Molecular subtypes were also profiled. Age, histological grade, ER, PR, and HER2 status were included in association analyses. In total, 183 patients were included. A hundred and forty patients had pure DCIS, and 43 patients had DCIS with invasion. The luminal A subtype accounted for 49.7% of all cases, the HER2-positive subtype for 27.9%, and only 10.4% and 12.0% represented the luminal B and basal-like subtypes, respectively. Univariate analyses showed that histological Grade 2, Grade 3, and HER2-positive status were associated with DCIS with invasion, odds ratios 5.1 (P = 0.017), 5.2 (P = 0.01) and 3.34 (P = 0.001), respectively. However, only the HER2-positive status was of statistical significance in the multivariate logistic regression analyses after adjustment for other markers, odds ratio 3.8 (95%CI 1.4-10, P = 0.008). The 43 cases with invasion were further stratified into extensive or small DCIS components according to the percentage of DCIS to total tumor area using 25% as the cutoff point. Multinomial logistic regression with pure DCIS cases as reference showed that the HER2-positive status was associated only with the group showing an extensive DCIS component, odds ratio 6.2 (95%CI 1.8-21, P = 0.003), but not with the group having a small DCIS component. Our study demonstrates that HER2-positive status is an independent predictor for DCIS, with invasion presenting an extensive DCIS component, and favors the hypothesis that HER2 overexpression or gene amplification is involved in the transition from DCIS to invasive disease.

The impact of sentinel lymph node biopsy and magnetic resonance imaging on important outcomes among patients with ductal carcinoma in situ

The objective of this systematic review was to determine the impact of sentinel lymph node (SLN) biopsy and breast magnetic resonance imaging (MRI) on important outcomes for patients with ductal carcinoma in situ. We identified no study that directly evaluated important outcomes for SLN biopsy. So, we determined the incidence of SLN metastases among patients with ductal carcinoma in situ. Using American Joint Committee on Cancer criteria, the incidence of pN1 and pN1(mic) SLN metastases were 0.9% and 1.5%, respectively. Because the incidence of SLN metastasis is very low, SLN biopsy is not likely to affect important outcomes. We identified one study that directly evaluated important outcomes after breast MRI. In this study, the use of MRI did not affect local recurrence rates after breast-conserving surgery and radiation. Although MRI may identify occult multicentric or contralateral breast cancer in some patients, it may also lead to unnecessary biopsies and overtreatment.

Clinical applications of breast pathology: management of in situ breast carcinomas and sentinel node biopsy issues

The purpose of this article is to review the current clinical management of in situ breast carcinomas, including how specific aspects of a pathology report are used in clinical decision-making, and to discuss the current role of sentinel node biopsy in management of invasive breast carcinomas and ductal carcinoma in situ of the breast.

Sentinel lymph node biopsy and management of the axilla in ductal carcinoma in situ

Ductal carcinoma in situ (DCIS) of the breast historically has been a disease detected by physical examination, diagnosed by open surgical biopsy, and treated by mastectomy and axillary dissection. It is now increasingly detected by screening mammography, diagnosed by needle core biopsy, and treated by lumpectomy, with axillary dissection having been abandoned and sentinel node biopsy being used in axillary staging. However, outcomes related to sentinel node biopsy in DCIS have not been validated in well-controlled clinical trials. Current guideline recommendations are to use sentinel node biopsy when needle core biopsy is highly suspicious for invasive cancer or where there is a high-risk DCIS when lumpectomy identifies invasive breast cancer with the DCIS, or when mastectomy is performed for extensive DCIS. Routine use of sentinel node biopsy for DCIS is not supported.

The pen and the scalpel: effect of diffusion of information on nonclinical variations in surgical treatment

BACKGROUND

As information is disseminated about best practices, variations in patterns of care should diminish over time.

OBJECTIVE

To test the hypotheses that differences in rates of a surgical procedure are associated with type of insurance in an era of evolving practice guidelines and that insurance and site differences diminish with time as consensus guidelines disseminate among the medical community.

METHODS

We use lymph node dissection among women with ductal carcinoma in situ (DCIS) as an example of a procedure with uncertain benefit. Using a sample of 1051 women diagnosed from 1985 through 2000 at 2 geographic sites, we collected detailed demographic, clinical, pathologic, and treatment information through abstraction of multiple medical records. We specified multivariate logistic models with flexible functions of time and time interactions with insurance and treatment site to test hypotheses.

RESULTS

Lymph node dissection rates varied significantly according to site of treatment and insurance status after controlling for clinical, pathologic, treatment, and demographic characteristics. Rates of lymph node dissection decreased over time, and differences in lymph node dissection rates according to site and generosity of insurance were no longer significant by the end of the study period.

CONCLUSIONS

We have demonstrated that rates of a discretionary surgical procedure differ according to nonclinical factors, such as treatment site and type of insurance, and that such unwarranted variation decreases over time with diminishing uncertainty and in an era of diffusion of clinical guidelines.

Recent advances and current controversies in the management of DCIS of the breast

Ductal carcinoma in situ (DCIS) is commonly diagnosed today, mainly due to widespread use of screening mammography. Despite a better understanding of its biological behavior, many issues regarding its optimal management remain controversial. The biological behavior of DCIS has been associated with distinct molecular and histological features (such as expression of COX2, Ki67, c-erbB2, p53 mutation, presence or absence of comedonecrosis, nuclear grade, hormone receptor status, etc.). Recent advances in the diagnosis of DCIS include using magnetic resonance imaging, and the use of stereotactic-guided directional vacuum-assisted biopsy (DVAB). Ductoscopy and ductal lavage have a limited role in the management of DCIS. Surgical treatment of DCIS includes simple local excision to various forms of wider excision (segmental resection or quadrantectomy), or even mastectomy (either simple or skin-sparing). Radiotherapy following breast-conserving surgery significantly reduces local recurrence rates. Axillary lymph node dissection is not required for the management of DCIS; however, during the last decade, sentinel lymph node biopsy is increasingly used to exclude the presence of axillary metastases (when invasive disease is present within the DCIS). This approach has many advantages (including the avoidance of a second surgery if invasive disease is diagnosed within the DCIS) and should be considered when there is an increased probability for the presence of invasive breast cancer within the DCIS. The role of other minimally invasive methods (such as the "therapeutic" application of the DVAB technique, radiofrequency ablation, laser therapy, cryotherapy and brachytherapy) in the management of small DCIS remains unproven. Tamoxifen should be considered in the management of selected patients with DCIS, such as patients with hormone receptor positive DCIS, young patients, and patients without risk factors for potential side effects. Additionally, and controversial, there is evidence that aromatase inhibitors may be better than tamoxifen in the management of DCIS.

Expression patterns of lymphangiogenic and angiogenic factors in a model of breast ductal carcinoma in situ

BACKGROUND

Foci of invasion are found in greater than 20% of excised specimens of breast ductal carcinoma in situ (DCIS). Since lymphangiogenesis markers are associated with the potential for increased lymph node metastasis, the purpose of the current study was to determine expression of lymphangiogenesis molecular markers in a model of aggressive DCIS.

METHODS

From the MCF10A xenograft model, comedo type MCF10DCIS.com cells, premalignant MCF10AT, and invasive MCF10CA1a.cl1 cells were tested. Invasion was tested by Matrigel invasion assays (Becton-Dickinson, Bedford, MA). Gene expression was determined by reverse transcriptase-polymerase chain reaction and protein expression by immunoblot, normalized to beta-actin.

RESULTS

MCF10DCIS.com cells were 4-fold more invasive than MCF10AT cells (P < .01), and expressed several-fold more mRNA and protein than MCF10AT and MCF10CA1a.cl1 cells for vascular endothelial growth factor C, vascular endothelial growth factor D, and lymphatic vessel endothelial hyaluronan receptor 1 (P < .01).

CONCLUSIONS

A subset of comedo-type DCIS cells are invasive, and expression of lymphangiogenesis markers is greater at the mRNA and protein levels than by invasive cancer cells (P < .01). These additional molecular markers may characterize aggressive DCIS more precisely.

Sentinel node biopsy is important in mastectomy for ductal carcinoma in situ

BACKGROUND

There is uncertainty about the utility of sentinel node biopsy (SNB) for ductal carcinoma in situ (DCIS) and its potential to avoid axillary lymph node dissection (ALND) in patients undergoing mastectomy for DCIS.

METHODS

A review was conducted of 179 patients who underwent mastectomy with sentinel node biopsy for DCIS without invasion or microinvasion on premastectomy pathology review.

RESULTS

The sentinel node identification rate was 98.9% (177/179). Twenty (11.3%) of 177 mastectomies for DCIS had a positive SNB: two micrometastasis (pN1mi) and 18 isolated tumor cells [pN0(i+)]. Unsuspected invasive cancer was found in 20 (11.2%) of 179 mastectomies, eight T1mic, five T1a, three T1b, and four T1c tumors. Sentinel nodes were identified in 19 of 20 patients with invasive cancer and four were positive: one pN1mi and three pN0(i+). Eighteen of 19 patients with unsuspected invasive cancer were able to avoid axillary dissection on the basis of SNB results. Of the 159 patients whose final pathology revealed DCIS without invasion, a sentinel node was identified in 158 (99.4%). The SNB was positive in 16 patients (10.1%): one pN1mi and 15 pN0(i+). Three patients underwent ALND on the basis of positive SNBs and in each the SNB was the only positive node.

CONCLUSIONS

11% of patients undergoing mastectomy for DCIS were found to have invasive cancer on final pathology. The use of SNB during mastectomy for DCIS allowed nearly all such patients to avoid axillary dissection. These results support routine use of SNB during mastectomy for DCIS.

Outcomes for Women With Ductal Carcinoma-in-Situ and a Positive Sentinel Node: A Multi-Institutional Audit

BACKGROUND

A positive sentinel lymph node (SLN) has been reported in 6% to 13% of patients with ductal carcinoma in situ (DCIS). Although it is well established that nodal status for invasive disease is prognostically important, the clinical relevance of a positive SLN in patients with DCIS remains undetermined.

METHODS

SLN biopsy was performed on 470 high-risk patients with DCIS (22% of all patients with DCIS) at 3 institutions. Of these, 43 (9%) had SLN metastases. Pathology findings of positive cases were reviewed, and follow-up was obtained. At 2 of the 3 institutions, data were also collected on DCIS patients who had negative findings on SLN biopsy. For these 414 patients, univariate analyses of tumor characteristics were performed to identify factors associated with node positivity.

RESULTS

Extensive disease requiring mastectomy (p = 0.02) and the presence of necrosis (p = 0.04) were associated with an increased risk of nodal positivity. Three (7%) of the 43 SLN-positive patients had macrometastases (pN1), 4 (9%) had micrometastases (pN1mi), and 36 (84%) had single tumor cells or small clusters (pN0(i+)). Of the 25 women that underwent completion axillary dissection, one was found to have a macrometastasis. On pathological review of the primary lesion, 2 (5%) of 43 patints were found to have microinvasion, and 2 (5%) lymphovascular invasion. Nine of 43 (21%) high-risk DCIS patients with a positive SLN and 9/470 (2%) of all high-risk DCIS patients were upstaged to AJCC stage I or II as a result of the SLN biopsy. At a median (range) follow-up of 27 (3-88) months, 1 patient had developed hepatic metastases. This patient had immunohistochemistry detected isolated tumor cells in her SLN (N0(i+)), and upon pathologic review, was found to have high-grade DCIS with microinvasion.

CONCLUSION

SLN biopsy for high-risk DCIS patients is a mean of detecting those who may have unrecognized invasive disease and therefore are at risk for distant disease.