Comparative analysis of conventional ultrasound and shear wave elastography features in primary breast diffuse large B-cell lymphoma

BACKGROUND

Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare subtype of non-Hodgkin lymphoma that accounts for < 3% of extranodal lymphomas and 1% of breast tumors. Its diagnosis and management are challenging because of its rarity, heterogeneity, and aggressive behavior. Conventional ultrasound (US) is the first-line imaging modality for breast lesions; however, it has limited specificity and accuracy for PB-DLBCL. Shear wave elastography (SWE) is a novel US technique that measures tissue stiffness and may reflect the histological characteristics and biological behavior of breast lesions.

AIM

To compare the conventional US and SWE features of PB-DLBCL and evaluate their diagnostic performance and prognostic value.

METHODS

We retrospectively reviewed the clinical data and US images of 32 patients with pathologically confirmed PB-DLBCL who underwent conventional US and SWE before treatment. We analyzed conventional US features (shape, margin, orientation, echo, posterior acoustic features, calcification, and vascularity) and SWE features (mean elasticity value, standard deviation, minimum elasticity value, maximum elasticity value, and lesion-to-fat ratio) of the PB-DLBCL lesions. Using receiver operating characteristic curve analysis, we determined the optimal cutoff values and diagnostic performance of conventional US and SWE features. We also performed a survival analysis to assess the prognostic value of conventional US and SWE features.

RESULTS

The results showed that the PB-DLBCL lesions were mostly irregular in shape (84.4%), microlobulated or spiculated in margins (75%), parallel in orientation (65.6%), hypoechoic in echo (87.5%), and had posterior acoustic enhancement (65.6%). Calcification was rare (6.3%) and vascularity was variable (31.3% avascular, 37.5% hypovascular, and 31.3% hypervascular). The mean elasticity value of PB-DLBCL lesions was significantly higher than that of benign breast lesions (113.4 ± 46.9 kPa vs 27.8 ± 16.4 kPa, P < 0.001). The optimal cutoff value of the mean elasticity for distinguishing PB-DLBCL from benign breast lesions was 54.5 kPa, with a sensitivity of 93.8%, specificity of 92.9%, positive predictive value of 93.8%, negative predictive value of 92.9%, and accuracy of 93.3%. The mean elasticity value was also significantly correlated with Ki-67 expression level (r = 0.612, P < 0.001), which is a marker of tumor proliferation and aggressiveness. Survival analysis showed that patients with higher mean elasticity values (> 54.5 kPa) had worse overall survival (OS) and progression-free survival (PFS) than those with lower mean elasticity values (< 54.5 kPa) (P = 0.038 for OS and P = 0.027 for PFS).

CONCLUSION

Conventional US and SWE provide useful information for diagnosing and forecasting PB-DLBCL. SWE excels in distinguishing PB-DLBCL from benign breast lesions, reflects tumor proliferation and aggressiveness, and improves disease management.

Primary Breast Diffuse Large B-Cell Lymphoma in a 42-Year-Old Female: A Case Report and Review of Literature

Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare localized extranodal lymphoma. It is mainly diagnosed by pathological examination due to the lack of specific clinical and imaging manifestations. Whole-body positron emission tomography-computed tomography (PET-CT) is widely used in determining clinical staging and guiding clinical treatment. As part of comprehensive treatment, targeted therapy with rituximab, intrathecal methotrexate injection and consolidation radiotherapy remain controversial in treating PB-DLBCL, but the comprehensive treatment based on full-course of chemotherapy is still widely used as the first-line treatment. Comprehensive treatment often leads to a sharp decline in the immunity of elderly patients with malignancy. In this situation, surgery may be a good chance to improve their life quality without serious complications. We present a rare case of PB-DLBCL during the coronavirus disease 2019 (COVID-19) pandemic. The patient underwent chest CT scan to screen COVID-19 and a mass of left breast was accidentally found. Because of the city lockdown policy in Wuhan, she did not seek medical help until noticing that the mass was gradually enlarged. Both ultrasonography and mammography indicated that the lesion was breast cancer. However, ultrasound-guided core needle biopsy revealed diffuse large B-cell lymphoma of breast and PET-CT scan showed that the lesion was a primary hypermetabolic tumor of left breast. The patient subsequently received comprehensive treatment based on six cycles of rituximab-cyclophosphamide, hydroxydaunomycin, oncovin, prednisone (R-CHOP) chemotherapy.

A novel classification based on B-cell receptor signal gene expression correlates with prognosis in primary breast diffuse large B-cell lymphoma

Primary breast diffuse large B-cell lymphoma (PB-DLBCL), the most common histologic subtype of lymphoid malignancy in the breast, is a clinically and genetically heterogeneous disease that has insufficient systematic studies on the pathological and molecular features, optimal treatment scheme, as well as the prognostic factors. The aim of our study was to identify biomarkers and distinct subtypes of PB-DLBCLs and then evaluate the prognosis of this rare malignant lymphoma. We carried out hierarchical clustering analysis to evaluate protein expressions of potential biomarkers detected by immunohistochemistry staining of samples from 68 PB-DLBCL patients. The gene expression data from TCGA database was obtained to validate the identified clusters. We identified three robust clusters based on the B-cell receptor (BCR) signaling pathway, including two recognized NF-κB-dependent and PI3K-dependent clusters, and a distinct subset of PB-DLBCL with NF-κB-independent anti-apoptotic overexpression plus PI3K signaling, which exhibited an evolving definition and distinctive characters of a cluster group. Furthermore, survival analysis results showed an inferior outcome in NF-κB-dependent cluster patients and favorable survival in the PI3K-dependent cluster patients, suggesting an important predictive value of the three clusters. Our study provided a new perspective for understanding clinical complexity of PB-DLBCLs, and gave evidence for finding targeted biomarkers and strategies.

[Prognosis analysis of primary breast diffuse large B cell lymphoma]

Objective: To investigate the clinical characteristics, therapy modality and prognosis of primary breast diffuse large B-cell lymphoma(PB-DLBCL). Methods: A total of 68 patients with PB-DLBCL treated in Tianjin Medical University Cancer Institute and Hospital were enrolled between January 1, 2004 and January 31, 2017. Clinicopathological data were retrospectively analyzed. 67 patients were female and only one male. The median age was 56 years old. 46 patients had Ann Arbor clinical stageⅠ~Ⅱ disease, and the other 22 were stage Ⅲ~Ⅳ. The patients with and without B symptom were 11 and 57, respectively. Kaplan-Meier method was used for univariate analysis to calculate the 5-year overall survival (OS) rate and 5-year progress-free survival (PFS) rate, compared using the log rank test. Cox regression analysis was used for multivariate analysis. Results: The 1, 3, 5-year OS rate were 84.0%, 78.0% and 73.0%, and 1, 3, 5-year PFS rate were 80.0%, 71.0% and 51.0%, respectively. Univariate analysis indicated that eastern cooperative oncology group (ECOG) score, Ann Arbor clinical stage, international prognostic index (IPI) score, risk stratification, B symptom, β2-microglobulin(β2-MG) level, size of the tumor and cycles of chemotherapy were prognostic factors for OS (all P<0.05), and Ann Arbor clinical stage, IPI score, risk stratification and B symptom were prognostic factors for PFS (all P<0.05). Multivariate analysis indicated that Ann Arbor clinical stage was independent prognostic factor for OS(P=0.029) and B symptom was independent prognostic factor for PFS(P=0.028). Conclusions: Prognosis of PB-DLBCL was relatively good. Ann Arbor clinical stage and B symptom were independent prognostic factors for OS and PFS, respectively.

Role of radiation therapy in primary breast diffuse large B-cell lymphoma in the Rituximab era: a SEER database analysis

Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is an uncommon extranodal non-Hodgkin's lymphoma (NHL), which was traditionally treated with anthracycline-containing regimens followed by consolidative radiation therapy (RT) to add therapeutic benefits. The introduction of anti-CD20 antibody rituximab for the treatment of B-cell NHLs has significantly improved the clinical outcome of these malignant diseases. It is unclear, however, whether consolidative RT could still add therapeutic benefits for PB-DLBCL patients treated with rituximab. To answer this important question, we used the Surveillance, Epidemiology, and End Results (SEER) database to evaluate the impact of RT on the clinical outcomes of PB-DLBCL patients in the rituximab era. Information on patient age, year of diagnosis, stage, race, laterality, and RT status for PB-DLBCL patients diagnosed between 2001 and 2014 were extracted. Kaplan-Meier survival curves were plotted, and log-rank test was used to compare the potential survival difference. Multivariate analysis using Cox proportional hazards model was employed to determine the impact of RT and other factors such as age, race, tumor laterality, stage, and year of diagnosis on survival. Among the 386 patients identified, the median follow-up time was 45 months (range, 0-167 months); the median age was 64 years (range, 19-93 years); 33.9% of the patients were younger than 60 years of age; 69.9% of the patients were stage I; 79.0% were white; 51.8% received RT. The 5-year OS and cause-specific survival (CSS) for the whole cohort were 72.3% and 82.5%, respectively. The 5-year OS was significantly superior for patients who received RT compared to those who did not receive RT (78.1% vs. 66.0%, P = 0.031). In multivariable analysis, RT remained significantly associated with improved OS (P = 0.026). In summary, our study suggests that RT still adds significant therapeutic benefits for patients with PB-DLCBL in the rituximab era.