The presentation, management and outcome of patients with ductal carcinoma in situ (DCIS) with microinvasion (invasion ≤1 mm in size)-results from the UK Sloane Project

Utility of Surgical Axillary Staging in Microinvasive Ductal Carcinoma In Situ: A National Cancer Database Analysis

BACKGROUND

Surgical axillary staging (ASx) of patients with microinvasive ductal carcinoma in situ (cT1mi) is debated due to the low occurrence of nodal metastasis. This study aimed to assess the utility of surgical axillary staging for clinically node-negative (cN0) T1mi breast cancer patients.

METHODS

This retrospective cohort study analyzed data from the National Cancer Database (NCDB) to investigate the axillary status of patients with cT1mi breast cancer between 2012 and 2019. Patient demographics, clinical characteristics, treatment methods, and pathologic findings were collected.

RESULTS

Of 10,843 patients, 9220 (85%) underwent ASx, whereas 1623 (15%) did not. Of the 4190 patients who underwent mastectomy, 244 (6%) did not undergo ASx, whereas 3946 (94%) did, 373 (9%) of whom were pN+. Of the 9069 patients who underwent ASx and had known nodal status, 8512 (94%) were pN- and 557 (6%) were pN+. The factors independently associated with increased odds of having positive nodes were younger age (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.01-1.03; p < 0.001), black race (OR, 1.51; 95% CI, 1.12-2.10; p = 0.007), lymphovascular invasion (OR, 13.72; 95% CI, 10.25-18.36; p < 0.001), and mastectomy (OR, 1.98; 95% CI, 1.57-2.51; p < 0.001). Among the pN+ patients, only 64 (1%) had ≥3 positive nodes and would require axillary lymph node dissection (ALND).

CONCLUSION

Surgical axillary staging is commonly performed for patients with cT1mi breast cancer despite the pN- status of most and the disproportionate morbidity associated with ASx. Identifying factors that predict a higher likelihood of pN+ status could allow for personalized surgical approaches, reducing unnecessary ASx for many patients.

Treatment patterns and clinical outcomes of patients with HER2-positive T1micN0 breast cancer: a single-center analysis

We conducted a retrospective analysis of 213 patients with HER2+ T1micN0 breast cancer. Patients with ≥5 foci of microinvasion received more aggressive treatment with higher rates of sentinel lymph node biopsy and adjuvant chemotherapy/HER2-targeted therapy (CT/H2TT) than patients with 1-4 foci. We did not detect significant differences in invasive disease-free survival between patients with 1-4 and ≥5 foci, or between patients with ≥5 foci who did and did not receive adjuvant CT/H2TT.

Clinicopathological features of microinvasive lobular carcinoma

AIMS

Microinvasive lobular carcinoma (MILC) is a rare form of minimally invasive carcinoma with incomplete pathological and clinical characterisation. We sought to identify the clinical and pathological features of MILC diagnosed at our institution between 2009 and 2023.

METHODS AND RESULTS

Patient demographic, pathological and clinical data were collected. Patients with a prior or synchronous history of invasive carcinoma were excluded. The study cohort included 30 female patients with a median age of 53 years. The most common imaging target was microcalcifications (63%). MILC was diagnosed on biopsy alone in three cases (10%), excision alone in 22 cases (73%) and on both biopsy and excision in five cases (17%). Most MILCs were unifocal (57%). MILCs were associated with classic lobular carcinoma in-situ (LCIS) in 90% of cases, florid LCIS in 27% and pleomorphic LCIS in 17%. None of 21 patients (70%) who underwent sentinel lymph node biopsy had lymph node involvement. Biomarker status was available in 16 (53%) MILC; 12 were oestrogen receptor+/progesterone receptor+/human epidermal growth factor receptor 2- (ER+/PR+/HER2-), two were ER+/PR-/HER2-, one was ER-/PR-/HER2+ and one was ER-/PR-/HER2 2+ but insufficient for fluorescence in-situ hybridisation (FISH) analysis. Median follow-up was 49 months. A patient with MILC at the excision margin of the index excision specimen did not undergo re-excision; 15 months later she developed an ipsilateral invasive carcinoma with ductal and lobular features and died of disease 73 months after initial diagnosis. All other 29 patients are alive with no evidence of disease.

CONCLUSION

MILC is a relatively indolent tumour arising in classic and variant LCIS, with a low risk of axillary or distant metastases.

Prediction of Microinvasion in Breast Ductal Carcinoma in Situ Using Conventional Ultrasound Combined with Contrast-Enhanced Ultrasound Features: A Two-Center Study

BACKGROUND

To develop and validate a model based on conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) features to preoperatively predict microinvasion in breast ductal carcinoma in situ (DCIS).

PATIENTS AND METHODS

Data from 163 patients with DCIS who underwent CUS and CEUS from the internal hospital was retrospectively collected and randomly apportioned into training and internal validation sets in a ratio of 7:3. External validation set included 56 patients with DCIS from the external hospital. Univariate and multivariate logistic regression analysis were performed to determine the independent risk factors associated with microinvasion. These factors were used to develop predictive models. The performance was evaluated through calibration, discrimination, and clinical utility.

RESULTS

Multivariate analysis indicated that centripetal enhancement direction (odds ratio [OR], 13.268; 95% confidence interval [CI], 3.687-47.746) and enhancement range enlarged on CEUS (OR, 4.876; 95% CI, 1.470-16.181), lesion size of ≥20 mm (OR, 3.265; 95% CI, 1.230-8.669) and calcification detected on CUS (OR, 5.174; 95% CI, 1.903-14.066) were independent risk factors associated with microinvasion. The nomogram incorporated the CUS and CEUS features achieved favorable discrimination (AUCs of 0.850, 0.848, and 0.879 for the training, internal and external validation datasets), with good calibration. The nomogram outperformed the CUS model and CEUS model (all P < .05). Decision curve analysis confirmed that the predictive nomogram was clinically useful.

CONCLUSION

The nomogram based on CUS and CEUS features showed promising predictive value for the preoperative identification of microinvasion in patients with DCIS.

Could breast multiparametric MRI discriminate between pure ductal carcinoma in situ and microinvasive carcinoma?

BACKGROUND

Ductal carcinoma in situ (DCIS) is often reclassified as invasive cancer in the final pathology report of the surgical specimen. It is of significant clinical relevance to acknowledge the possibility of underestimating invasive disease when utilizing preoperative biopsies for a DCIS diagnosis. In cases where such histologic upgrades occur, it is imperative to consider them in the preoperative planning process, including the potential inclusion of sentinel lymph node biopsy due to the risk of axillary lymph node metastasis.

PURPOSE

To assess the capability of breast multiparametric magnetic resonance imaging (MP-MRI) in differentiating between pure DCIS and microinvasive carcinoma (MIC).

MATERIAL AND METHODS

Between January 2018 and November 2022, this retrospective study enrolled patients with biopsy-proven DCIS who had undergone preoperative breast MP-MRI. We assessed various MP-MRI features, including size, morphology, margins, internal enhancement pattern, extent of disease, presence of peritumoral edema, time-intensity curve value, diffusion restriction, and ADC value. Subsequently, a logistic regression analysis was conducted to explore the association of these features with the pathological outcome.

RESULTS

Of 129 patients with biopsy-proven DCIS, 36 had foci of micro-infiltration on surgical specimens and eight were diagnosed with invasive ductal carcinoma (IDC). The presence of micro-infiltration foci was significantly associated with several MP-MRI features, including tumor size (P <0.001), clustered ring enhancement (P <0.001), segmental distribution (P <0.001), diffusion restriction (P = 0.005), and ADC values <1.3 × 10-3 mm2/s (P = 0.004).

CONCLUSION

Breast MP-MRI has the potential to predict the presence of micro-infiltration foci in biopsy-proven DCIS and may serve as a valuable tool for guiding therapeutic planning.

Atypia detected during breast screening and subsequent development of cancer: observational analysis of the Sloane atypia prospective cohort in England

OBJECTIVE

To explore how the number and type of breast cancers developed after screen detected atypia compare with the anticipated 11.3 cancers detected per 1000 women screened within one three year screening round in the United Kingdom.

DESIGN

Observational analysis of the Sloane atypia prospective cohort in England.

SETTING

Atypia diagnoses through the English NHS breast screening programme reported to the Sloane cohort study. This cohort is linked to the English Cancer Registry and the Mortality and Birth Information System for information on subsequent breast cancer and mortality.

PARTICIPANTS

3238 women diagnosed as having epithelial atypia between 1 April 2003 and 30 June 2018.

MAIN OUTCOME MEASURES

Number and type of invasive breast cancers detected at one, three, and six years after atypia diagnosis by atypia type, age, and year of diagnosis.

RESULTS

There was a fourfold increase in detection of atypia after the introduction of digital mammography between 2010 (n=119) and 2015 (n=502). During 19 088 person years of follow-up after atypia diagnosis (until December 2018), 141 women developed breast cancer. Cumulative incidence of cancer per 1000 women with atypia was 0.95 (95% confidence interval 0.28 to 2.69), 14.2 (10.3 to 19.1), and 45.0 (36.3 to 55.1) at one, three, and six years after atypia diagnosis, respectively. Women with atypia detected more recently have lower rates of subsequent cancers detected within three years (6.0 invasive cancers per 1000 women (95% confidence interval 3.1 to 10.9) in 2013-18 v 24.3 (13.7 to 40.1) in 2003-07, and 24.6 (14.9 to 38.3) in 2008-12). Grade, size, and nodal involvement of subsequent invasive cancers were similar to those of cancers detected in the general screening population, with equal numbers of ipsilateral and contralateral cancers.

CONCLUSIONS

Many atypia could represent risk factors rather than precursors of invasive cancer requiring surgery in the short term. Women with atypia detected more recently have lower rates of subsequent cancers detected, which might be associated with changes to mammography and biopsy techniques identifying forms of atypia that are more likely to represent overdiagnosis. Annual mammography in the short term after atypia diagnosis might not be beneficial. More evidence is needed about longer term risks.

An MRI-Based Radiomics Nomogram to Distinguish Ductal Carcinoma In Situ with Microinvasion From Ductal Carcinoma In Situ of Breast Cancer

RATIONALE AND OBJECTIVES

Accurate preoperative differentiation between ductal carcinoma in situ with microinvasion (DCISM) and ductal carcinoma in situ (DCIS) could facilitate treatment optimization and individualized risk assessment. The present study aims to build and validate a radiomics nomogram based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) that could distinguish DCISM from pure DCIS breast cancer.

MATERIALS AND METHODS

MR images of 140 patients obtained between March 2019 and November 2022 at our institution were included. Patients were randomly divided into a training (n = 97) and a test set (n = 43). Patients in both sets were further split into DCIS and DCISM subgroups. The independent clinical risk factors were selected by multivariate logistic regression to establish the clinical model. The optimal radiomics features were chosen by the least absolute shrinkage and selection operator, and a radiomics signature was built. The nomogram model was constructed by integrating the radiomics signature and independent risk factors. The discrimination efficacy of our nomogram was assessed by using calibration and decision curves.

RESULTS

Six features were selected to construct the radiomics signature for distinguishing DCISM from DCIS. The radiomics signature and nomogram model exhibited better calibration and validation performance in the training (AUC 0.815, 0.911, 95% confidence interval [CI], 0.703-0.926, 0.848-0.974) and test (AUC 0.830, 0.882, 95% CI, 0.672-0.989, 0.764-0.999) sets than in the clinical factor model (AUC 0.672, 0.717, 95% CI, 0.544-0.801, 0.527-0.907). The decision curve also demonstrated that the nomogram model exhibited good clinical utility.

CONCLUSION

The proposed noninvasive MRI-based radiomics nomogram model showed good performance in distinguishing DCISM from DCIS.

Prognostic Markers of Microinvasive Breast Carcinoma: A Systematic Review and Meta-Analysis

(1) Background: The prognostic factors of microinvasive (≤1 mm) breast carcinoma are not completely clear. The aim of this study was to perform a systematic review and meta-analysis to clarify these factors. (2) Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was followed. Two databases were interrogated, PubMed and Embase, and papers in English were included to address this question. The selected studies were those that reported on female patients affected by microinvasive carcinoma, and on prognostic factors with a hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS). (3) Results: In total, 618 records were identified. After removing duplicates (166), identification, and screening (336 by title and abstract alone, 116 by full text and eventual supplementary material), 5 papers were selected. Seven different meta-analyses were conducted in this study, all referring to DFS, analyzing the following prognostic factors: estrogen receptor, progesterone receptor, HER2 status, multifocality and grade of microinvasion, patient's age, and lymph node status. Only lymph node status was associated with prognosis and DFS (total number of cases: 1528; Z = 1.94; p = 0.05). The other factors examined did not significantly affect prognosis (p > 0.05). (4) Conclusions: Positive lymph node status significantly worsens prognosis in patients with microinvasive breast carcinoma.

Clinical significance of microinvasive breast cancer across the different subtypes and human epidermal growth factor receptor 2 expression levels

PURPOSE

The clinical behavior, prognosis, and management of microinvasive breast cancer (MiBC) is controversial. We aimed to clarify its significance across different subtypes and the role of human epidermal growth factor receptor 2 (HER2) expression in MiBC.

METHODS

We analyzed 1530 patients with T1mi (tumor size ≤ 0.1 cm), node-negative breast cancer who underwent breast conserving surgery or total mastectomy between 2001 and 2020 at the Asan Medical Center (AMC).

RESULTS

When divided into four subtypes, hormone receptor (HR)+/HER2-, HR+ /HER2+ , HR-/HER2+ , and HR-/HER2-, HR-/HER2+ had the highest prevalence rate of 38.5% in MiBC patients. In a median follow-up period of 74 months (0-271 months), 103 (6.7%) patients had recurrent tumor, and 95 (6.2%) had local recurrence. Disease-free survival (DFS) and local recurrence-free survival (LRFS) were worst in the HR-/HER2+ group. The five-year DFS for the HR-/HER2+ group was 92.2%, while it was 97.1% for the HR+/HER2- group (p = 0.024 The five-year LRFS for HER2- patients were better than that of HER2+ MiBC patients, which were 97.1 and 93.8%, respectively (p = 0.010). Univariate and multivariate Cox regression analyses showed that the HR-/HER2+ group had relatively higher risk of recurrence compared to the HR+/HER2- group (hazard ratio [HR] = 2.332, 95% confidence interval [CI] 1.412-3.852, p = 0.001 unadjusted; HR = 3.346, 95% CI 1.408-7.953, p = 0.006 adjusted).

CONCLUSION

HER2 overexpression was significantly associated with adverse clinicopathologic parameters and increased local recurrence risk in MiBC. Therefore, more understanding of the clinical behavior of HER2 in MiBC will enable tailoring of adjuvant therapy for these patients.

Ductal Carcinoma In Situ (DCIS) and Microinvasive DCIS: Role of Surgery in Early Diagnosis of Breast Cancer

Advances in treatments, screening, and awareness have led to continually decreasing breast cancer-related mortality rates in the past decades. This achievement is coupled with early breast cancer diagnosis. Ductal carcinoma in situ (DCIS) and microinvasive breast cancer have increasingly been diagnosed in the context of mammographic screening. Clinical management of DCIS is heterogenous, and the clinical significance of microinvasion in DCIS remains elusive, although microinvasive DCIS (DCIS-Mi) is distinct from "pure" DCIS. Upfront surgery has a fundamental role in the overall treatment of these breast diseases. The growing number of screen-detected DCIS diagnoses with clinicopathological features of low risk for local recurrence (LR) allows more conservative surgical options, followed by personalised adjuvant radiotherapy plans. Furthermore, studies are underway to evaluate the validity of surgery omission in selected low-risk categories. Nevertheless, the management, the priority of axillary surgical staging, and the prognosis of DCIS-Mi remain the subject of debate, demonstrating how the paucity of data still necessitates adequate studies to provide conclusive guidelines. The current scientific scenario for DCIS and DCIS-Mi surgical approach consists of highly controversial and diversified sources, which this narrative review will delineate and clarify.

Crossroads: the role of biomarkers in the management of lumps in the breast

Premalignant lesions in the breast pose a difficult decision-making problem, whether to treat proactively and accept the side effects or to engage in watchful waiting and possibly encounter a later diagnosis of invasive cancer. A biomarker or set of biomarkers to inform on the individual progression risk would be beneficial to the patient and cost-effective for the healthcare system. The gene products of tumor progression may be expressed in early non-cancerous ("premalignant") lesions, where they are associated with a high probability for full transformation in breast cancers. One such molecule is the OPN splice variant-c. OPN-c is also present in a fraction of the premalignant lesions, where it reflects an elevated risk for progression to cancer within 5 years, regardless of the lesion's subtype. This marker has the properties needed to facilitate decisions to treat at the premalignant stage.

Long-term outcomes and effects of hypofractionated radiotherapy in microinvasive breast cancer: Analysis from a randomized trial

PURPOSE

The natural history of microinvasive (T1mi) breast cancer is uncertain. The objective was to evaluate long-term local and distant recurrence rates following breast conserving surgery (BCS) in a prospective cohort of patients with T1mi compared to T1a-2 disease who received whole breast irradiation (WBI) in the context of a randomized trial of hypofractionation.

METHODS

1234 patients with T1-2 N0 breast cancer were randomized to receive adjuvant WBI of 42.5Gy in 16 daily fractions, or 50Gy in 25 daily fractions after BCS. An analysis of patients with T1mi tumors compared with T1a-2 disease was performed. Kaplan-Meier estimates of local recurrence (LR), distant recurrence, and overall survival (OS) were compared using the log-rank test.

RESULTS

Median follow-up was 12 years. T1mi was found in 3% (n = 38) of patients. The 10-year LR rate was 22.6% in T1mi vs. 6.9% in T1a-2 breast cancer [hazard ratio (HR) = 3.73; 95% confidence interval (CI): 1.93, 7.19; p < 0.001]. The 10-year risk of distant recurrence was 5.1% for T1mi, and 12.1% for T1a-2 disease (HR = 0.56; 95% CI: 0.19, 1.84; p = 0.36). Ten-year OS was 91.5% in T1mi and 84.4% in T1a-2 disease, (HR = 0.48; 95% CI: 0.18, 1.30; p = 0.14). Rates of LR did not differ whether treated by hypofractionation or conventional fractionation (HR = 1.21; 95% CI: 0.35, 4.18; p = 0.77).

CONCLUSIONS

The risk of LR was considerably higher in patients with T1mi compared to T1a-2 tumors, but OS remained very good. Future research should evaluate the utility of wider local excision and boost radiation to optimize local control for microinvasive breast cancer.