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

Magnetic lymphatic tracing for omission of sentinel lymph node biopsies in mastectomy patients: a community cancer center experience

BACKGROUND

Patients with ductal carcinoma in situ (DCIS) and patients undergoing risk reduction mastectomy may undergo sentinel lymph node biopsy (SLNB) at the time of mastectomy to complete axillary staging were an underlying invasive malignancy to be found on final pathology. Among patients with DCIS undergoing mastectomy, 15-29% of patients will have invasive disease on final pathology; therefore, approximately 70-85% of patients may benefit from avoiding SLNB. Superparamagnetic tracers (SPMT) have been proven to be non-inferior to the standard radioisotope and blue dye combination. SPMT remains active for several weeks, allowing a large proportion of DCIS and genetic carrier patients to potentially avoid SLNB in the setting of mastectomy. We hypothesize the use of SPMT will reduce the number of SLNB performed in patients undergoing mastectomy for DCIS and risk reduction, ultimately reducing the number of complications associated with axillary surgery. We seek to report our community cancer center's experience with SPMT and omission of SLNB in the DCIS and prophylactic mastectomy patient population.

METHODS

We performed a retrospective review of 52 female patients with DCIS or known genetic predisposition undergoing mastectomy. SPMT (Magtrace®, Endomag Ltd, Cambridge, UK) was injected ipsilateral to DCIS and bilaterally for prophylactic mastectomy patients. Our primary outcome was rate of return to the operating room (OR) for delayed SLNB. Secondary outcomes included post-operative complications within 30 days of surgery and operative time. We compared outcomes to a control group of 28 women undergoing mastectomy for DCIS or for risk reduction who underwent SLNB at their index operation in traditional fashion. Continuous variables were reported using median and interquartile ranges (IQR) and were compared using the Mann-Whitney U test. Categorical data were reported using frequency and percent and were compared using Pearson's Chi-Square or Fisher's Exact test, as appropriate. Alpha was set to 0.05 to determine statistical significance.

RESULTS

There was a total of 80 patients (52 SPMT, 28 control). Median age of SPMT patients was 49.5 (IQR 40-60.75) vs. 54.5 (48 - 65) in the traditional tracer group. vs. control group. 57.7% of SPMT patients underwent mastectomy for DCIS vs. 89.3% in the control group. Eight SPMT patients (15.4%) had invasive ductal carcinoma (IDC) on final pathology and seven of those patients underwent delayed SLNB (87.5%). None of the delayed SLNB were positive for metastatic disease. Rates of post-operative complications were similar between the two groups, including hematoma, seroma, and surgical site infection. OR times were also similar with median OR time 202 min (min) for the SPMT group vs. 195 min for the control group.

CONCLUSION

Use of SPMT avoided SLNB in 84.6% of our patients. We found no difference in rates of post-operative complications or operative times in patients using SPMT for omission of SLNB at time of mastectomy compared to the control group. Our findings suggest SLNB can be avoided in a majority of patients undergoing mastectomy for DCIS or risk reduction in the setting of genetic predisposition.

The Use of Sentinel Lymph Node Biopsy in Patients Undergoing Mastectomy for DCIS

BACKGROUND

Current guidelines do not recommend routine sentinel node biopsy (SLNB) for ductal carcinoma in situ (DCIS), except in the setting of mastectomy or microinvasive disease. This study aimed to evaluate national SLNB utilization in women undergoing upfront mastectomy for DCIS, identify predictors of SLNB utilization, and determine the percentage with a positive SLNB.

METHODS

A retrospective cohort analysis was performed using the NCDB of women with clinical DCIS who underwent upfront mastectomy between 2012 and 2017. Demographic and clinicopathologic variables were compared between patients who underwent SLNB and those who did not. Multivariate logistic regression models were used to identify factors associated with SLNB utilization and positive SLNB.

RESULTS

About 38,973 patients met inclusion criteria: 34,231 (88%) underwent SLNB and 4742 (12%) had no surgical axillary staging. Most patients were age 50-69 (51%), non-Hispanic White (71%), with private insurance (66%). On multivariate analysis, older patients were less likely to receive SLNB (P < .01), while patients with higher grade DCIS were more likely to undergo SLNB (P < .01). In those who underwent SLNB (n = 34,231), only 1,149 (3.4%) had nodal involvement. Non-Hispanic Black patients had increased odds of a positive SLNB (P < .01), while those with estrogen receptor positive disease were less likely to be node positive (OR 0.68, P < .001).

CONCLUSIONS

While 88% of patients had a SLNB, only 3.4% were found to be node positive. Given this low rate, it is reasonable to consider SLNB omission in select patients with low grade, hormone receptor positive DCIS undergoing upfront mastectomy.

Nodal Surgery for Patients ≥ 70 Undergoing Mastectomy for DCIS? Choose Wisely

BACKGROUND

Routine sentinel lymphadenectomy (SLNB) for early-stage HR+/HER2- breast cancer in women ≥70 is discouraged by Choosing Wisely, but whether SLNB can be routinely omitted in women ≥70 with DCIS undergoing mastectomy is unclear. This study aims to evaluate rates of axillary surgery and nodal positivity (pN+) in this population to determine the impact of axillary surgery on treatment decisions.

METHODS

Females ≥70 with DCIS undergoing mastectomy were identified from the National Cancer Database (2012-2020). The rate of upstaging to invasive cancer (≥pT1) or pN+ was assessed. Subset analyses were conducted for ER+ patients. Adjuvant therapies were evaluated among ≥pT1 patients after stratifying by nodal status.

RESULTS

Of 9,030 patients, 1,896 (21%) upstaged to ≥pT1. Axillary surgery was performed in 86% of patients, predominantly sentinel lymphadenectomy (SLNB, 65%). Post hoc application of Choosing Wisely criteria demonstrated that 93% of the entire cohort and 97% of ER+ DCIS patients could have avoided axillary surgery. Nodal positivity was 0.3% among those who didn't upstage, and 12% among those upstaging to ≥pT1, with <2% having pN2-3 disease, irrespective of receptor subtype. Node-positive patients had higher adjuvant therapy usage, but there was no recommendation for adjuvant chemotherapy or radiation for 71% and 66% of pN+ patients, respectively.

CONCLUSIONS

Axillary surgery can be omitted for most patients ≥70 undergoing mastectomy for ER+ DCIS, aligning with recommendations for invasive cancer, and omission can be considered in those with ER- disease. Future guidelines incorporating preoperative imaging, as in the SOUND trial, may aid in identifying patients benefiting from axillary surgery.

Feasibility of Omitting Sentinel Lymph Node Biopsy in an Under-screened Cohort of Breast Cancer Patients With a Premastectomy Diagnosis of Ductal Carcinoma In Situ

BACKGROUND

Nodal involvement in ductal carcinoma in situ (DCIS) is rare. In patients with DCIS diagnosis prior to mastectomy, a sentinel lymph node biopsy (SLNB) is usually performed during mastectomy, to avoid the risk of reoperation and the non-identification of SLN subsequently, should there be an upgrade to invasive cancer. We aimed to study the feasibility of omitting SLNB in an under-screened cohort, with mostly symptomatic patients and DCIS diagnosis before mastectomy, by determining the upgrade rate to invasive cancer/ DCIS microinvasion (DCISM) and its associated risk factors.

METHODS

Patients with pure DCIS diagnosis premastectomy were reviewed retrospectively. Patients with known DCISM or invasive cancer before mastectomy and bilateral cancers were excluded. Patients' demographics, radiological and pathological data premastectomy were analyzed.

RESULTS

A total of 189 patients were included. The mean age was 53.8 (range: 29-85) years old. About 64.4% presented with symptoms. 36.0% and 15.3% upgraded to invasive cancer and DCISM on mastectomy respectively. Palpable tumor (P = .0036), large size on ultrasound (P = .0283), tumor seen on mammogram and ultrasound (P = .0082), ultrasound-guided biopsy (P < .0001), high-grade DCIS on biopsy (P = .0350) and no open biopsy/lumpectomy before mastectomy (P < .0001) were associated with the upgrade, with the latter factor remaining significant after multivariable analysis. Nodal involvement was 8.47% and was associated with invasive cancer (P < .0001).

CONCLUSION

In a cohort who had DCIS diagnosis before mastectomy and were mostly symptomatic, the upgrade rate was 51.3%. Despite the high upgrade rate, nodal involvement remained comparable. Risk factors could select patients for omission of upfront SLNB, with a delayed SLNB planned if needed.

De-escalation of Sentinel Lymph Node Biopsy in Patients With Ductal Carcinoma In Situ

Introduction Current guidelines recommend that sentinel lymph node biopsy (SLNB) be performed in patients with ductal carcinoma in situ (DCIS) undergoing mastectomy, in patients for whom the location of excision may compromise future SLNB, or if there is a high suspicion or risk of upstaging to invasive cancer on final pathology. Whether axillary surgery should be performed in patients with DCIS remains controversial. Our study aimed to examine the factors associated with the upgrade of DCIS to invasive cancer on final pathology and sentinel lymph node (SLN) metastases to evaluate whether axillary surgery may be safely omitted in DCIS. Methods Patients with a diagnosis of DCIS on core biopsy who underwent surgery with axillary staging between 2016 and 2022 were identified from our pathology database and retrospectively reviewed. Patients who underwent surgical management of DCIS without axillary staging and those treated for local recurrence were excluded. Results Out of 65 patients, 35.3% of patients were upstaged to the invasive disease on final pathology. 9.23% of cases had a positive SLNB. Predictive factors associated with upstaging to invasive cancer included palpable mass on clinical examination (P = 0.013), presence of a mass on preoperative imaging (P = 0.040), and estrogen receptor status (P = 0.036). Conclusion Our results support ongoing opportunities for the de-escalation of axillary surgery in patients with DCIS. In a subset of patients undergoing surgery for DCIS, SLNB may be omitted as the risk of upstaging to invasive cancer is low. Patients with a mass on clinical examination or imaging and negative estrogen receptor (ER) lesions have a higher risk of upstaging to invasive cancer, where a sentinel lymph node biopsy should be performed.

Upgrade Rate of Ductal Carcinoma In Situ to Invasive Carcinoma and the Clinicopathological Factors Predicting the Upgrade Following a Mastectomy: A Retrospective Study

Background The rate of upgrading ductal carcinoma in situ (DCIS) to invasive cancer varies widely in the literature with no consensus regarding sentinel lymph node biopsy (SLNB) for DCIS; however, some guidelines do recommend it in the event of a mastectomy. The primary aim of this study was to determine the upgrade rate of DCIS to invasive carcinoma (IC) in patients undergoing mastectomy for DCIS and identify the clinicopathological predicting factors for the upgrade. The secondary aim was to determine the SLNB positivity rate. Methodology We retrospectively analysed consecutive patients with DCIS diagnosed through a biopsy who then underwent mastectomy over a 10-year period (2010 to 2020). Clinical, radiological, and histological variables were collected from medical records. Results We studied 143 women (mean age = 57.4 years, range = 26-85 years) who underwent mastectomy for DCIS identified on biopsy. Almost two-thirds (62.9%, 90/143) of the patients were detected on screening mammography, while 35.6% (51/143) were diagnosed following presentation with either an area of palpable concern or nipple discharge. The most common mammographic presentation of DCIS was calcification (83.9%, 120/143), and, in 85.9% of the patients, the mammographic lesion was more than 20 mm. High-grade DCIS was noted in 76.9% of preoperative biopsy results, while the rest was either low or intermediate-grade DCIS. Overall, 24.5% (35/143) were upgraded to IC (upgraded group) on postoperative histology, whereas 108/143 remained DCIS postoperatively (pure DCIS group). The positivity rate of SLNB was 4.8%. Multifocality was the only significant predictor of IC on multivariate analyses of clinicopathological predictors (odds ratio = 3.0, 95% confidence interval = 1.0-8.7). The presence of comedonecrosis was higher in the upgraded group compared to the pure DCIS group (42.9% vs. 27.8%), but this was not statistically significant. Conclusions In our study cohort, nearly one in four (24.5%) patients were upgraded from DCIS to IC on postoperative histology, with an SLNB positivity rate of 4.8%. This is important when counselling patients regarding the risk of coincident occult IC and the importance of SLNB at the time of mastectomy. Multifocality on preoperative imaging was the only significant predictive factor. Based on this result, we recommend that SLNB should also be considered if patients have multifocal DCIS and planned for oncoplastic breast-conserving surgery. However, further studies are required to investigate the association between multifocal DCIS and the risk of upgrading to IC.

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.

De-escalating axillary surgery in early-stage breast cancer

The role of axillary surgery has evolved over the last three decades from routine axillary lymph node dissection (ALND) to sentinel lymph node biopsy to omission of axillary surgery altogether in select patients. This evolution has been achieved through the design and conduct of multiple clinical trials demonstrating that ALND does not impact survival and is not necessary for local control in patients with early-stage breast cancer and limited nodal involvement. Importantly, this practice-changing shift mirrored the trend towards earlier stage at diagnosis and the recognition of the interplay between local and systemic therapies in maintaining local control. There are numerous clinical scenarios today in which axillary staging can be safely avoided, including (1) DCIS treated with lumpectomy, (2) at the time of contralateral prophylactic mastectomy, and (3) in elderly patients with early-stage, HR+/HER2-clinically node-negative (cN0) disease. Ongoing clinical trials seek to expand the cohorts in which surgical nodal staging can be omitted. These populations include a broader range of early-stage, cN0 patients undergoing upfront surgery, as seen in the SOUND, INSEMA, BOOG 2013-08, SOAPET and NAUTILUS trials. Omission of axillary surgery in cN0 patients with HER2+ or triple-negative disease treated with neoadjuvant chemotherapy is also being tested in the ASICS and EUBREAST-01 trials. Continued advances in imaging and the growing role of genomic assays in selecting patients for systemic therapy are likely to further minimize the need for axillary surgery; thereby further reducing the morbidity of local therapy for women with breast cancer.

Characterization of Suspicious Microcalcifications on Mammography Using 2D Shear-Wave Elastography

Our aim was to investigate the correlations between the findings of two-dimensional shear-wave elastography (2D-SWE) and the histopathologic results of microcalcifications (MCs) visualized using ultrasonography (USG). Fifty people with suspicious MCs without accompanying mass were evaluated. They underwent USG and 2D-SWE before USG-guided tru-cut biopsy. SWE values and histopathologic features were compared statistically. The variables between groups were analyzed using the Mann-Whitney U test. Receiver operating characteristic analysis was performed and cut-off values determined to discriminate malignancy, invasiveness and high grade. Pathology confirmed 27 malignant lesions (18 invasive ductal carcinomas, one invasive lobular and eight ductal carcinomas in situ) and 23 benign ones. There was a statistically significant difference between the SWE values of malignant and benign MCs (p < 0.001). The diagnostic performance of SWE for malignancy, invasiveness and high grade were as follows, repectively: sensitivity (93%, 83%, 88%), specificity (91%, 88%, 53%), positive predictive value (93%, 94%, 44%), negative predictive value (91%, 70%, 90%) and area under the curve (0.952, 0.885, 0.776). Cut-off values were determined as 57 kPa for malignancy, 124 kPa for invasiveness and 124.5 kPa for high grade. In conclusion, SWE is a useful method in clinical practice for characterizing MCs that can be visualized with USG.

Revisit the practice of lymph node biopsy in patients diagnosed as ductal carcinoma in situ before operation: a retrospective analysis of 682 cases and evaluation of the role of breast MRI

Background

The optimal axillary lymph node (ALN) management strategy in patients diagnosed with ductal carcinoma in situ (DCIS) preoperatively remains controversial. The value of breast magnetic resonance imaging (MRI) to predict ALN metastasis pre-operative DCIS patients was evaluated.

Methods

Patients with primary DCIS with or without pre-operative breast MRI evaluation and underwent breast surgery were recruited from single institution. The value of breast MRI for ALN evaluation, predictors of breast and ALN surgeries, upgrade from DCIS to invasive cancer, and ALN metastasis were analyzed.

Results

A total of 682 cases with pre-operative diagnosis of DCIS were enrolled in current study. The rate of upgrade to invasive cancer were found in 34.2% of specimen, and this upgrade rate is 23% for patients who received breast conserving surgery and 40.7% for mastectomy (p < 0.01). Large pre-operative imaging tumor size and post-operative invasive component were risk factors to ALN metastasis. Breast MRI had 53.8% sensitivity, 77.8% specificity, 14.9% positive predictive value, 95.9% negative predictive value (NPV), and 76.2% accuracy to predict ALN metastasis in pre-OP DCIS patients. In MRI node-negative breast cancer patients with MRI tumor size < 3 cm, the NPV was 96.4%, and all these false-negative cases were N1. Pre-OP diagnosed DCIS patients with MRI tumor size < 3 cm and node negative suitable for BCS could safely omit SLNB if whole breast radiotherapy is to be performed.

Conclusion

Breast MRI had high NPV to predict ALN metastasis in pre-OP DCIS patients, which is useful and could be provided as shared decision-making reference.

When is Sentinel Lymph Node Biopsy Useful in Ductal Carcinoma In Situ? The Experience at a Latin American Cancer Center

Introduction

Ductal carcinoma in situ (DCIS) accounts for 15% of breast cancers. Surgery is the main treatment, and the use of sentinel node biopsy (SLNB) is restricted to patients at risk of infiltration, which is estimated to be around 26%.

Materials and methods

Aimed at evaluating the benefit of SLNB in patients with DCIS at the Breast and Soft Tissue Functional Unit of the National Cancer Institute (INC for its initials in Spanish), a descriptive observational study of a retrospective cases series was conducted between August 1, 2013, and September 30, 2018.

Results

A total of 40 patients with a median age of 57 years were included in the study; 62.5% of them underwent mastectomy with SLNB, and the remaining 37.5% underwent conservative surgery with SLNB. 100% of sentinel nodes were identified, by using lymphoscintigraphy in 95%. Sentinel node was positive in four patients (10%), three of whom had infiltration in the surgical specimen reported. With a follow-up of 49 months, only one patient had a local relapse. None of the patients had axillary or distant recurrence.

Conclusions

SLNB in DCIS should be limited to patients with risk factors for infiltration (tumor size greater than 3 cm, comedo-type histology, and high-grade DCIS), and patients with an indication for mastectomy. Its percentage of complications is low, and a high identification percentage in surgical groups with adequate training.

Ductal Carcinoma in situ: Underestimation of Percutaneous Biopsy and Positivity of Sentinel Lymph Node Biopsy in a Brazilian Public Hospital

Background

Mammography screening has become widely spread and provided a marked increase in ductal carcinoma in situ (DCIS) diagnosis. In DCIS, the ductal epithelium proliferates without invasion through the basal cell membrane. However, histologic underestimation can happen in some cases.

Objective

To analyze the rate of histologic underestimation (histopathologic results upgraded to invasive carcinoma after surgery) and the rate of positive results of sentinel lymph node biopsy (SLNB) in patients diagnosed with DCIS in a Brazilian public hospital.

Methods

We reviewed medical records of all consecutive patients admitted between 2009 and 2013 whose initial diagnosis was DCIS through core needle biopsy. DCIS cases with a high risk of invasion underwent SLNB. We excluded cases with invasion or micro-invasion components in the first biopsy.

Results

A total of 86 women were included, most with microcalcifications as the primary radiological lesion (73.2%), and underwent preoperative biopsy, with an invasive component in 21 (24.4%) in the final pathology report. Most had invasive carcinoma of no special type (NST): 52.3% (n = 11) and microinvasive tumors (7 cases, 33.3%). The main factors associated with histologic underestimation were nodular lesion (61.9%, p<0.001) and an ultra-sonography-guided biopsy (71.4%, p=0.0005). The positivity rate of SLNB was 4.3%. All these patients underwent mastectomy, and the initial histologic pattern was solid DCIS.

Conclusion

The “histologic underestimation” rate among patients with DCIS was not low, and less than 5% of patients who underwent SLNB had axillary positivity. This result suggests that patients who have DCIS and a high risk of invasion and undergoing mastectomy should have SLNB. As to the patients who will undergo lumpectomy, SLNB could be omitted and could be performed if patients have upgraded to invasive breast cancer.