Histo-biological comparative analysis of bilateral breast cancer

A Retrospective Study on the Clinicopathologic Characteristics and Outcomes of 179 Cases of Synchronous and Metachronous Bilateral Breast Cancer in China

OBJECTIVE

To investigate the clinicopathologic characteristics and outcome of bilateral breast cancer (BBC) in the Chinese population.

METHODS

A retrospective study was conducted on 7797 cases with primary breast cancer, including 7618 cases of unilateral breast cancer (UBC) and 179 cases of BBC. Among the latter, there were 108 cases of synchronous BBC (SBBC) and 71 cases of metachronous BBC (MBBC).

RESULTS

In the present study, the incidence of SBBC and MBBC are 1.39% and 0.91% among the general population, respectively. In comparison of UBC and BBC, SBBC and MBBC, there are significant differences in the common clinicopathological characteristics, such as pathologic stage, hormone receptor (HR) status and molecular type. In respect of the surgical treatment of BBC, 49.72% of the patients chose mastectomy. The 3-year disease free survival (DFS) for SBBC and MBBC are 94.4% and 96.9%, respectively. There is no difference in the overall survival (OS) and DFS between SBBC and MBBC. The histological grade and type of surgery on tumors of both sides are important influencing factors of DFS in the BBC patients.

CONCLUSION

There are statistical differences in the clinicopathological characteristics and outcomes between SBBC and MBBC among the Chinese population. Therefore, the treatment of BBC patients should be individualized.

Clinical characteristics and the associated risk factors of the development of bilateral breast cancers: A case-control study

Background

The clinical impacts of bilateralism on prognosis and clinical decision-making remain contradictory particularly in areas with low incidence and delayed diagnosis of primary breast cancer. Identification of women at risk of bilateral breast cancer is required to improve patient management and to design the appropriate surveillance.

Methods

A total of 1083 women were enrolled and analyzed for the presence of synchronous and metachronous bilateral breast cancer as cases and unilateral breast cancer as controls during the median follow-up of 4.8 years.

Results

The incidence of bilateral breast cancer was 7.5% (81 of 1083). In comparison with unilateral breast cancers, bilateral cases were significantly diagnosed in younger women (P = 0.037, mean age was 35.6 years) who had a larger tumor size (P = 0.012, mean tumor size was 8 cm in diameter). Histological type of lobular cancer was identified as one of the risk factors for the development of contralateral breast cancer (OR 5.564, 95% CI: 3.219-9.620) and synchronous bilateral breast cancer (OR 2.561, 95% CI: 1.182-5.550). Bilateral breast cancer had significantly shorter progression-free survival (Mean survival was 26.6 vs 52.5 months for bilateral and unilateral breast cancers, respectively; P = 0.001) and shorter time to develop distant metastasis (Mean survival was 41.7 vs 104 months for bilateral and unilateral breast cancers, respectively; P = 0.001).

Conclusion

Patients with first primary breast tumors with lobular histological type and advanced stages were observed to have higher risks for the development of contralateral breast cancers.

Application of MRI Radiomics-Based Machine Learning Model to Improve Contralateral BI-RADS 4 Lesion Assessment

Objective

This study aimed to explore the potential of magnetic resonance imaging (MRI) radiomics-based machine learning to improve assessment and diagnosis of contralateral Breast Imaging Reporting and Data System (BI-RADS) category 4 lesions in women with primary breast cancer.

Materials and Methods

A total of 178 contralateral BI-RADS 4 lesions (97 malignant and 81 benign) collected from 178 breast cancer patients were involved in our retrospective dataset. T1 + C and T2 weighted images were used for radiomics analysis. These lesions were randomly assigned to the training (n = 124) dataset and an independent testing dataset (n = 54). A three-dimensional semi-automatic segmentation method was performed to segment lesions depicted on T2 and T1 + C images, 1,046 radiomic features were extracted from each segmented region, and a least absolute shrinkage and operator feature selection method reduced feature dimensionality. Three support vector machine (SVM) classifiers were trained to build classification models based on the T2, T1 + C, and fusion image features, respectively. The diagnostic performance of each model was evaluated and tested using the independent testing dataset. The area under the receiver operating characteristic curve (AUC) was used as a performance metric.

Results

The T1+C image feature-based model and T2 image feature-based model yielded AUCs of 0.71 ± 0.07 and 0.69 ± 0.07 respectively, and the difference between them was not significant (P > 0.05). After fusing T1 + C and T2 imaging features, the proposed model’s AUC significantly improved to 0.77 ± 0.06 (P < 0.001). The fusion model yielded an accuracy of 74.1%, which was higher than that of the T1 + C (66.7%) and T2 (59.3%) image feature-based models.

Conclusion

The MRI radiomics-based machine learning model is a feasible method to assess contralateral BI-RADS 4 lesions. T2 and T1 + C image features provide complementary information in discriminating benign and malignant contralateral BI-RADS 4 lesions.

The number of FoxP3-positive tumor-infiltrating lymphocytes in patients with synchronous bilateral breast cancer

PURPOSE

In breast cancer, FoxP3-positive tumor-infiltrating lymphocytes (FoxP3+ TILs) vary depending on lymph node status, histological grade, and subtype. All these studies have compared the numbers of FoxP3+ TILs among different hosts, but recruitment of FoxP3+ TILs might depend on each individual's immune environment and each tumor's biological characteristics. In the present study, FoxP3+ TIL numbers were investigated in patients with synchronous bilateral breast cancer (SBBC) to determine the factors that affect FoxP3+ TIL recruitment in the same anti-tumor immune environment.

METHODS

Patients diagnosed with SBBC who underwent curative surgery at two institutions were enrolled in this study. Patients who underwent primary systemic therapy or who were diagnosed with ductal carcinoma in situ or who had distant metastases at diagnosis were excluded. The average numbers of Foxp3+ TILs were determined from the scores of five high-power microscopic fields (HPF). The associations between Foxp3+ TIL numbers and the clinicopathological features of bilateral breasts in a single individual were examined.

RESULTS

Nuclear grade (NG) (p = 0.007) and subtype (p = 0.03), but not size (p = 0.18) and axillary lymph node (p = 0.23) were significantly associated with increase of FoxP3 + TIL numbers by univariate analysis. Further, only NG was a statistically significant clinicopathological factor for change in the number of FoxP3+ TILs by multivariate analysis (p = 0.046) CONCLUSIONS: There was no relationship between FoxP3+ TIL numbers and cancer progression as reflected in tumor size and axillary lymph node in patients with SBBC. Aggressive biological factors, especially high NG, were significantly related to enhanced recruitment of FoxP3+ TILs.

Clinicopathological Profile and Treatment Outcomes of Bilateral Breast Cancer: A Study from Tertiary Cancer Center in South India

Background: Bilateral breast cancer (BBC) is a rare clinical entity with limited data regarding clinicopathological aspects and treatment guidelines. Materials and Methods: This was an observational study of patients diagnosed with BBC from August 2012 to July 2014. Synchronous breast cancers (SBCs) was defined as two tumors diagnosed within an interval of 6 months and metachronous breast cancer (MBC) as second cancer diagnosed after 6 months. Results: Out of 750 breast cancer patients seen during a 2-year period, 35 had BBC. Ten patients were diagnosed as SBC whereas 25 patients as MBC. Among patients with MBC, the average time for development of contralateral breast cancer was 5 years. In 8 patients, the contralateral breast cancer was detected mammography whereas rest 27 patients were detected by clinical breast examination. At a median follow-up of 24 months, 23 (66%) patients were disease free, 9 (26%) patients had disease relapse, and 3 (8%) patients succumbed to the progressive disease. Conclusions: Every patient with breast cancer should be regularly followed up with clinical breast examination at a more frequent interval. The role of frequent clinical breast examination appears more than mammography especially beyond 5 years for early detection of contralateral breast cancer.

Comparative genomic analysis reveals bilateral breast cancers are genetically independent

Bilateral breast cancer (BBC) poses a major challenge for oncologists because of the cryptic relationship between the two lesions. The purpose of this study was to determine the origin of the contralateral breast cancer (either dependent or independent of the index tumor). Here, we used ultra-deep whole-exome sequencing and array comparative genomic hybridization (aCGH) to study four paired samples of BBCs with different tumor subtypes and time intervals between the developments of each tumor. We used two paired primary breast tumors and corresponding metastatic liver lesions as the control. We tested the origin independent nature of BBC in three ways: mutational concordance, mutational signature clustering, and clonality analysis using copy number profiles. We found that the paired BBC samples had near-zero concordant mutation rates, which were much lower than those of the paired primary/metastasis samples. The results of a mutational signature analysis also suggested that BBCs are independent of one another. A clonality analysis using aCGH data further revealed that paired BBC samples was clonally independent, in contrast to clonal related origin found for paired primary/metastasis samples. Our preliminary findings show that BBCs in Han Chinese women are origin independent and thus should be treated separately.

Challenges of treating incidental synchronous bilateral breast cancer with differing tumour biology

A 59-year-old woman with right breast mass was diagnosed with invasive ductal carcinoma (IDC). Workup consisted of bilateral diagnostic mammogram and ultrasound (US); both showed a right breast mass with normal left breast. Core biopsy showed IDC with estrogen receptor negative (ER-)/progesterone receptor negative (PR-) and HER2/neu positive receptor status. The patient underwent carboplatin-based chemotherapy with Herceptin. The mass completely resolved. The patient desired to proceed with bilateral total mastectomy with right sentinel lymph node biopsy (SLNB). Pathology showed complete resolution of the right-sided breast mass without malignancy in right SLN. Incidentally, IDC was found in the left breast specimen, which was ER+/PR+ and HER 2/neu negative. Tumour board consensus was to obtain a left axilla US with MRI in 6 months if the US was unremarkable. Biologically different synchronous bilateral breast cancer poses a difficult clinical challenge for management due to differing responses to treatment. Use of MRI may be a diagnostic option in women who choose contralateral prophylactic mastectomy.

Synchronous Bilateral Breast Cancers

BACKGROUND

Bilateral breast cancer (BBC) is not an uncommon entity in contemporary breast clinics. Improved life expectancy after breast cancer treatment and routine use of contra-lateral breast mammography has led to increased incidence of BBC. Our study objective was to define the epidemiological and tumour characteristics of BBC in India.

MATERIALS AND METHODS

A total of 1251 breast cancer patients were treated during the period January 2007 to March 2015 and 30 patients were found to have BBC who constituted the study population (60 tumour samples). Synchronous bilateral breast cancers (SBC) was defined as two tumours diagnosed within an interval of 6 months and a second cancer diagnosed after 6 months was labelled as metachronous breast cancer (MBC). Analyses of patient and tumour characteristics were done in this prospective data base of BBC patients.

RESULTS

Median patient age was 66 years (range 39-85). Majority of the patients had SBC (n=28) and in 12 patients the second tumour was clinically occult and detected only by mammography of the contra-lateral breast. The second tumour was found at lower tumour size compared to the first in 73% of cases and was negative for axillary metastasis in 80% of cases (24/30). Infiltrating ductal carcinoma was the commonest histological type (n=51) and majority of the tumours were ER/PR positive (50/60). Her2 was overexpressed in 13 tumours (21%). Over 70% (22/30) of patients had similar histology in both breasts and amongst them grade concordance was present in about 69% (15/22) of patients. Concordance rates of ER, PR and Her2 statuses were 83%, 80% and 90% respectively. Bilateral mastectomy was the commonest surgery performed in 80% of the patients followed by bilateral breast conservation in 13%. At the end of study period, 26 patients were alive and disease free. Median survival was 29 months (range 3-86 months).

CONCLUSION

In most patients with BBC, the second tumour is identified at an early stage than index tumours supporting the importance of contralateral breast cancer screening at the time of primary diagnosis and during follow-up. BBC occurs more frequently in old age group and majority of these tumours are estrogen dependent. There is good pathological concordance between the index tumour and the contralateral breast cancer.

Breast-Conserving Surgery in Bilateral Breast Cancer

BACKGROUND

Bilateral breast cancer (BBC) may present as synchronous (SBC) or metachronous breast cancer (MBC). Optimal surgical management of BBC patients is not well-defined. In this study, we report on histopathology, treatment, and outcomes in BBC patients.

METHODS

Upon Institutional Review Board approval, we identified BBC patients diagnosed and treated for invasive breast cancer between 1999 and 2007. Retrospective chart review for demographics, histopathology, treatment, and outcomes was performed, and factors associated with BCS choice were collected. Contraindication to BCS was defined as any of the following one-breast findings: multicentric disease, tumor considered too large for BCS, and a patient without a nominal breast size for acceptable cosmetic results. McNemar's test for matched pairs (binary variables) or the paired t test (continuous variables) were used to examine if a pathologic characteristic differed within a cancer pair. Kaplan-Meier methods estimated overall survival (OS).

RESULTS

A total of 203 BBC patients (119 SBC, 84 MBC) comprised our study group. Histopathologic characteristics of the first and second cancers diagnosed in both the SBC and MBC patients were very similar in histologic type and molecular profiles. Overall, 57% of MBC patients underwent breast-conserving surgery (BCS) at initial diagnosis versus 34% of patients with SBC. BCS contraindications were similar in both groups: 16 (34%) MBC patients and 28 (36%) SBC patients. Kaplan-Meier OS estimates at 5 and 10 years were 86 and 78% for MBC, and 87 and 77% for SBC patients, respectively.

CONCLUSIONS

OS was excellent for both the MBC and SBC groups. Contraindications to BCS did not differ between groups. However, patients with SBC were less likely to undergo BCS compared with patients with MBC at the time of initial diagnosis.