Clinicopathological characteristics and prognosis of metaplastic carcinoma of the breast

Clinical analysis of metaplastic breast carcinoma with distant metastases: A multi‑centre experience

Metaplastic breast cancer (BC-Mp), which includes a range of epithelial and mixed epithelial-mesenchymal tumours, are rare malignancies with an unfavourable prognosis. The limited literature on BC-Mp focuses mainly on retrospective data for radically treated patients. Notably absent are studies dedicated to the palliative treatment of BC-Mp with distant metastases. The present retrospective study investigated treatment modalities and prognosis in a multi-centre cohort of 31 female participants diagnosed with distant metastatic BC-Mp, including 7 patients with de novo metastatic disease. The median age of the patients was 61 years (range, 33-87 years), with 38.7% presenting local lymph node involvement. Lungs were the most common site for the metastatic disease (61.3%). Median Ki-67 index was 50% (range, 35-70%), and 80.7% of cases were classified as grade 3. Human epidermal growth factor receptor 2 (HER2)+ and estrogen receptor+ were detected in 12.9 and 6.5% of cases, respectively. A total of 62.4% of patients received first-line palliative systemic treatment. The 1- and 2-year overall survival (OS) were 38.5 and 19.2%, respectively. Receiving ≥1 line of palliative treatment was significantly associated with improved OS (P<0.001). Factors such as age, Ki-67 index, HER2 or hormonal status, presence of specific epithelial or mesenchymal components, location of metastases or chemotherapy regimen type did not influence OS. The present study provided insights into the clinicopathological profile, systemic treatment experience, prognostic factors and OS data of BC-Mp with distant metastases, emphasizing the imperative for clinical trials in this population.

Metaplastic breast cancer: an all-round multidisciplinary consensus

Metaplastic breast cancer (MpBC) is a rare and aggressive histologic subtype of breast cancer (BC) characterized by the presence of at least two cellular types, commonly epithelial and mesenchymal components. Despite growing evidence that MpBC is a unique entity, it has long been treated as a variant of nonspecial type (NST) BC. MpBC typically shows the phenotype of triple-negative breast cancer (TNBC), but compared to NST-TNBC, it is a relatively chemorefractory tumor associated with worse outcomes. Therefore, there is an urgent need to develop management guidelines specifically for MpBC to improve the prognosis of patients with early MpBC. This expert consensus aims to guide diagnosis and standardize clinical management of early MpBC among treating physicians. We provide guidance on the challenging radiological and pathological diagnosis of MpBC. Evidence on the involvement of genetic predisposition in the development of MpBC is also explored. We emphasize the importance of a multidisciplinary approach for the treatment of patients with early MpBC. The optimal surgery and radiotherapy approach is presented, as well as the opportunity offered by novel therapeutic approaches to increase treatment response in this chemoresistant subtype. Appropriate management of patients with MpBC is critical to reduce the high risk of local and distant recurrence that characterizes this disease.

TROP2, androgen receptor, and PD-L1 status in histological subtypes of high-grade metaplastic breast carcinomas

AIMS

High-grade metaplastic breast carcinoma (HG-MBC) is a rare subtype of invasive breast carcinoma, mostly triple-negative. Metaplastic carcinomas are less responsive to neoadjuvant chemotherapy and are associated with a worse outcome than invasive carcinomas of no special type.

METHODS

Clinicopathological characteristics and immunophenotype were retrospectively assessed in a series of 65 patients diagnosed with HG-MBC between 2005 and 2017 at the Curie Institute (antibody panel: oestrogen receptor [ER], progesterone receptor [PR], androgen receptor [AR], human epidermal growth factor receptor 2 [HER2], programmed death ligand-1 [PD-L1], and trophoblast cell surface antigen 2 [TROP2]).

RESULTS

The median age at diagnosis was 59.5 years. Six (9%) patients had metastatic disease at diagnosis. Among the nonmetastatic patients receiving neoadjuvant therapy, 26% (5/19) achieved pathological complete response. Most tumours were pT1/pT2 (77%) and 12% were pN+. Histological subtypes (mixed, squamous, mesenchymal, and spindle cell) were 40%, 35.5%, 15.5%, and 9%, respectively. Tumour-infiltrating lymphocytes were low or moderate except when squamous differentiation was present. Most tumours were triple-negative (92%). AR and TROP2 were positive in 34% and 85% of the cases, respectively. PD-L1 was positive in tumour cells in 18% (cutoff: 1% of positive tumour cells) of the cases and in tumour-infiltrating immune cells in 40% (cutoff: 1% of tumour area) of the cases. Notably, spindle cell and mesenchymal metaplastic breast carcinomas were mostly PDL1-negative. Lastly, 21 (32.3%) cases were HER2-low, all being HER2 1+, with no HER2 2+.

CONCLUSION

Metaplastic breast carcinoma could benefit from tailored therapeutic strategies adapted to the phenotypic specificities of histological subtypes.

Case report and literature review on a large MBC with ulceration

RATIONALE

Metaplastic breast cancer (MBC) is a rare tumor of the breast, and skin ulceration of breast tumors is a difficult clinical problem that reduces the patient's quality of life.

PATIENT CONCERNS

There are currently no Standard Treatment Guidelines for MBC at present, and the treatment for the skin ulceration of breast tumors is limited in clinics.

DIAGNOSIS

Here, we report the case of a patient with a large MBC and skin ulceration, accompanied by exudation and odor.

INTERVENTION

The combined treatment of albumin paclitaxel and carrelizumab (anti-PD-1 immunotherapy) was effective in reducing the tumor, but it increased the severity of the skin ulceration. After taking traditional Chinese medicine, the skin ulceration healed completely. Then the patient underwent a mastectomy and radiotherapy.

OUTCOMES

The patient has a high quality of life and was in good condition after the comprehensive treatment.

LESSONS

This suggests that traditional Chinese medicine may have a good auxiliary therapeutic effect on the skin ulceration of MBC.

Prognostic Factor Analysis and Model Construction of Triple-Negative Metaplastic Breast Carcinoma After Surgery

Objective

The study aimed to analyze the prognostic factors of patients with triple-negative (TN) metaplastic breast carcinoma (MpBC) after surgery and to construct a nomogram for forecasting the 3-, 5-, and 8-year overall survival (OS).

Methods

A total of 998 patients extracted from the Surveillance, Epidemiology, and End Results (SEER) database were assigned to either the training or validation group at random in a ratio of 7:3. The clinical characteristics of patients in the training and validation sets were compared, and multivariate Cox regression analysis was used to identify the independent risk variables for the OS of patients with TN MpBC after surgery. These selected parameters were estimated through the Kaplan–Meier (KM) curves using the log-rank test. The nomogram for predicting the OS was constructed and validated by performing the concordance index (C-index), receiver operating characteristics (ROC) curves with area under the receiver operating characteristic curves (AUC), calibration curves, and decision curve analyses (DCAs). Patients were then stratified as high-risk and low-risk, and KM curves were performed.

Results

Multivariate Cox regression analysis indicated that factors including age, marital status, clinical stage at diagnosis, chemotherapy, and regional node status were independent predictors of prognosis in patients with MpBC after surgery. Separate KM curves for the screened variables revealed the same statistical results as with Cox regression analysis. A prediction model was created and virtualized via nomogram based on these findings. For the training and validation cohorts, the C-index of the nomogram was 0.730 and 0.719, respectively. The AUC values of the 3-, 5-, and 8-year OS were 0.758, 0.757, and 0.785 in the training group, and 0.736, 0.735, and 0.736 for 3, 5, and 8 years in the validation group, respectively. The difference in the OS between the real observation and the forecast was quite constant according to the calibration curves. The generated clinical applicability of the nomogram was further demonstrated by the DCA analysis. In all the training and validation sets, the KM curves for the different risk subgroups revealed substantial differences in survival probabilities (P <0.001).

Conclusion

The study showed a nomogram that was built from a parametric survival model based on the SEER database, which can be used to make an accurate prediction of the prognosis of patients with TN MpBC after surgery.

[Effect of postmastectomy radiotherapy on survival outcomes of patients with metaplastic breast cancer]

OBJECTIVE

To evaluate the effect of postmastectomy radiotherapy (PMRT) on the overall survival (OS) and breast cancer-specific survival (BCSS) of patients with metaplastic breast cancer (MpBC) in comparison with those of patients with invasive ductal breast carcinoma (IDC).

METHODS

We selected the patients with pathologically confirmed MpBC and IDC who either received PMRT or not from the archived cases (from January, 1998 to December, 2016) in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. In total, 31 982 patients were selected, including 308 patients with MpBC and PMRT, 629 with MpBC and PMRT, and 31 045 with IDC and PMRT. All the included patients were above 18 years of age without distant metastases or a second primary cancer and underwent radical surgery. Baseline characteristics of the patients were compared among the 3 subgroups, and multivariate Cox regression and Kaplan-Meier analyses were performed for analyzing the prognostic factors of MpBC, OS, and BCSS.

RESULTS

The majority (81.2%) of patients with MpBC were older than 50 years, had pathological grade III (68%), and were negative for ER (75.9%) and PR (79.8%) and in stage T2-3 (71.3%) and N0-1 (85.6%). Multivariate Cox regression analysis showed that age, T stage, N stage, PMRT, and chemotherapy were significantly associated with the prognosis of patients with MpBC (P < 0.05), while pathological grade, ER status, or PR status did not significantly affect the prognosis (P>0.05). Kaplan-Meier analysis showed that the patients with MpBC and PMRT had better OS (HR=1.394, 95% CI: 1.125-1.727; P < 0.05) and BCSS (HR=1.390, 95% CI: 1.074-1.800; P < 0.05) than those with MpBC who did not receive PMRT; but after PMRT, the patients with MpBC had worse OS (HR=1.626, 95%CI: 1.386-1.908; P < 0.001) and BCSS (HR=1.710, 95% CI: 1.418-2.062; P < 0.001) as compared with those with IDC.

CONCLUSION

MpBC has unique clinicopathological features. In patients with MpBC, age, T stage, N stage, radiotherapy and chemotherapy are all the prognostic factors affecting the survival outcomes, and PMRT can improve the OS and BCSS of the patients.

MicroRNA-495/TGF-β/FOXC1 axis regulates multidrug resistance in metaplastic breast cancer cells

Triple-negative metaplastic breast carcinoma (MBC) poses a significant treatment challenge due to lack of targeted therapies and chemotherapy resistance. We isolated a novel MBC cell line, BAS, which showed a molecular and phenotypic profile different from the only other metaplastic cell model, HS578T cells. To gain insight behind chemotherapeutic resistance, we generated doxorubicin (HS-DOX, BAS-DOX) and paclitaxel (HS-TX, BAS-TX) resistant derivatives of both cell lines. Drug sensitivity assays indicated a truly multidrug resistant (MDR) phenotype. Both BAS-DOX and BAS-TX showed up-regulation of FOXC1 and its experimental down-regulation re-sensitized cells to doxorubicin and paclitaxel. Experimental modulation of FOXC1 expression in MCF-7 and MDA-MB-231 cells corroborated its role in MDR. Genome-wide expression analyses identified gene expression signatures characterized by up-regulation of TGFB2, which encodes cytokine TGF-β2, in both BAS-DOX and BAS-TX cells. Pharmacological inhibition of the TGF-β pathway with galunisertib led to down-regulation of FOXC1 and increase in drug sensitivity in both BAS-DOX and BAS-TX cells. MicroRNA (miR) expression analyses identified high endogenous miR-495-3p levels in BAS cells that were downregulated in both BAS MDR cells. Transient expression of miR-495-3p mimic in BAS-DOX and BAS-TX cells caused downregulation of TGFB2 and FOXC1 and re-sensitized cells to doxorubicin and paclitaxel, whereas miR-495-3p inhibition in BAS cells led to increase in resistance to both drugs and up-regulation of TGFB2 and FOXC1. Together, these data suggest interplay between miR-495-3p, TGF-β2 and FOXC1 regulating MDR in MBC and open the exploration of novel therapeutic strategies.

Benefit of adjuvant chemotherapy in patients with special histology subtypes of triple-negative breast cancer: a systematic review

PURPOSE

Breast cancer (BC) is a leading cause of morbidity, disability, and mortality in women, worldwide; triple-negative BC (TNBC) is a subtype traditionally associated with poorer prognosis. TNBC special histology subtypes present distinct clinical and molecular features and sensitivity to antineoplastic treatments. However, no consensus has been defined on the best adjuvant therapy. The aim of the review is to study the evidence from literature to inform the choice of adjuvant treatments in this setting.

METHODS

We systematically searched literature assessing the benefit of adjuvant chemotherapy in patients with TNBC special histotypes (PROSPERO: CRD42020153818).

RESULTS

We screened 6404 records (15 included). All the studies estimated the benefit of different chemotherapy regimens, in retrospective cohorts (median size: 69 patients (range min-max: 17-5142); median follow-up: 51 months (range: 21-268); mostly in Europe and USA). In patients with early-stage adenoid cystic TNBC, a marginal role of chemotherapy was reported. Similar for apocrine TNBC. Medullary tumors exhibited an intrinsic good prognosis with a limited role of chemotherapy, suggested to be modulated by the presence of tumor-infiltrating lymphocytes. A significant impact of chemotherapy on the overall survival was estimated in patients with metaplastic TNBC. Limitations were related to the retrospective design of all the studies and heterogeneous treatments received by the patients.

CONCLUSIONS

There is potential opportunity to consider treatment de-escalation and less intense therapies in some patients with early, special histology-type TNBC. International efforts are indispensable to validate prospective clinical decision models.

Patterns of Care and Survival of Metastatic Metaplastic Breast Cancer Patients

Background: Metaplastic breast cancer (MBC) is a rare, aggressive variant of breast cancer, usually triple negative disease and chemotherapy refractory. Despite this, the standard of care remains the same as invasive ductal breast cancer. We sought to analyze patterns of care and outcomes among patients with metastatic MBC.

Methods: Patients over 18 years diagnosed with metastatic MBC from 2004-2015 were identified in the National Cancer Database (NCDB). Clinical and demographic details were compared between two groups (chemotherapy vs no chemotherapy). Logistic regression was performed to assess for predictors of receiving chemotherapy. The Kaplan-Meier method was used to assess overall survival (OS) and Cox regression analysis was used to assess the impact of covariates on OS.

Results: There were 7,580 patients with MBC of which 417 (5.5%) presented with metastatic disease. Median age was 65 years (interquartile range (IQR) 54-76) and median follow up for living patients was 48 months (IQR 31-77). One hundred and fifty-six (37.4%) patients received chemotherapy. On multivariable logistic regression analyses, treatment at an academic facility was associated with an increased likelihood of receiving chemotherapy (OR 3.14, 95% CI 1.95-5.03, p<0.001) while age ≥65 years (OR 0.54, 95% CI 0.34-0.86, p=0.009) and receipt of hormonal therapy (OR 0.35, 95% CI 0.15-0.85, p=0.021) were associated with a decreased likelihood of receiving chemotherapy. On multivariable Cox regression analysis, higher Charlson-Deyo score (hazard ratio (HR) 1.35-1.78, p<0.05) was associated with worse survival while receipt of chemotherapy (HR 0.76, 95% CI 0.59-0.99, p=0.041) and having insurance (HR 0.34-0.47, p<0.05) were associated with improved survival. Patients who received chemotherapy had improved median (twelve versus eight months), one-year (51% versus 38%), and two-year (35% versus 21%) OS, as compared to those who did not receive chemotherapy (p=0.006). 

Conclusions: In this study of MBC patients, there was a survival benefit with palliative chemotherapy in the setting of metastatic disease. As expected, treatment was most often given to younger patients.

Different Patterns of Conditional Survival of Breast Cancer Patients by Age and Histologic Types: Evidence from the Korean Nationwide Registry

BACKGROUND

Conditional relative survival (CRS), which is the survival estimate of patients who have already survived for a certain period of time after diagnosis, could provide more relevant information on the current prognosis of cancer survivors than the standard 5-year relative survival (RS). This study aimed to estimate the 5-year CRS of Korean breast cancer patients.

METHODS

We identified 145,083 breast cancer cases diagnosed between 2002 and 2013 in the Korea Central Cancer Registry. The CRS was estimated for every year after diagnosis, according to sex, age, histologic type, and stage.

RESULTS

The 5-year RS at diagnosis was 90.8%, and the 10-year RS was 85.7%. The 5-year CRS was 91.0% and 94.3% at 1 year and 5 years after diagnosis, respectively. Very young and very old patients had worse 5-year CRS after 5 years of survival than those of other age groups (92.2% in the <40-year and 92.6% in the ≥70-year groups vs. 95.4% in 40-49-year, 94.3% in 50-59-year, and 93.7% in 60-69-year groups). The 5-year CRS of metaplastic carcinoma increased from 82.0% at diagnosis to 95.2% at 5 years after diagnosis, compared with that of lobular carcinoma (from 93.1% to 92.5%). Hardly any excess mortality (5-year CRS ≥ 95%) was seen within 7 years after diagnosis.

CONCLUSIONS

This study shows that the CRS of breast cancer survivors in Korea has increased, but varies by sex, age, stage, and histologic type.

IMPACT

These findings provide more detailed information to breast cancer survivors and clinicians.

Katanin P80 expression correlates with lymph node metastasis and worse overall survival in patients with breast cancer

OBJECTIVE

The aim of this study was to investigate the correlation of katanin P80 expression with clinicopathological features and overall survival (OS) in surgical breast cancer (BC) patients.

METHODS

Four hundred and fourteen BC patients underwent surgery were analyzed in this retrospective cohort study. Katanin P80 expression was examined by immunofluorescence assay. The median follow-up duration was 118.0 months (quantiles: 99.0-140.5 months), the last follow-up date was Jul 1st 2017.

RESULTS

Eighty-five patients (20.5%) with katanin P80 positive expression and 329 patients (79.5%) with katanin P80 negative expression were observed in this research. Katanin P80 positive expression was correlated with higher N stage (p< 0.001) and TNM stage (p< 0.001). K-M curve and log-rank test revealed that katanin P80 positive patients presented with shorter OS compared with katanin P80 negative patients (p< 0.001). Multivariate Cox's regression analysis disclosed that katanin P80 positive expression (p< 0.001) and histologic grade (p< 0.001) could independently predict unfavorable OS. Furthermore, subgroups analysis was performed, which illuminated that katanin P80 positive expression was correlated with shorter OS in all subgroups divided by molecular subtyping and TNM stage (all p< 0.05) except in TNM stage I subgroup (p= 0.573).

CONCLUSION

Katanin P80 expression positively correlated with lymph node metastasis and could abe a novel biomarker for prognosis in BC patients.

Metaplastic carcinoma of the breast with mesenchymal differentiation (carcinosarcoma). A unique presentation of an aggressive malignancy and literature review

Metaplastic carcinoma of the breast with mesenchymal differentiation (MCMD), previously known as carcinosarcoma, is a very rare and aggressive tumor that has been recently classified as a subtype of metaplastic breast carcinoma. It accounts for 0.08%-0.2% of all breast cancers, with only a few cases reported in the literature. Histologically, MCMD is characterized by a biphasic pattern of malignant epithelial and sarcomatous components without evidence of a transition zone between the two elements. We herein describe a unique case of metaplastic carcinoma of the breast with chondrosarcomatous differentiation in a postmenopausal woman who presented with a large, rapidly growing, ulcerated, bleeding mass and signs of impending sepsis. Metaplastic breast carcinomas (MBC) are rare and aggressive tumors. They are characterized by larger size, lower rates of axillary node involvement, higher rates of triple negativity and distal metastases, earlier local recurrence and poorer survival compared with classic invasive breast cancer. Because of the rarity of MBC, the optimal treatment has not been well defined. Surgery is the main curative treatment modality since MBC has shown a suboptimal response to standard chemotherapy. Patients with MBC may be appropriate candidates for novel targeted therapies.