Spindle cell carcinoma of the breast: a comprehensive analysis

Co-existence of malignant phylloid tumor and metaplastic malignant spindle cell carcinoma: case report

Phyllodes tumors (PTs) and Metaplastic Malignant Spindle Cell Carcinoma (MMSCC) are rare and challenging breast malignancies. MMSCC is even rarer and highly aggressive. Surgical excision is the mainstay of treatment for both, but MMSCC generally carries a poorer prognosis. A 46-year-old woman with a history of breast augmentation 4 years ago presented with a rapidly progressing right breast mass. Imaging and core biopsy suggested a malignant PT. A right mastectomy with latissimus dorsi flap reconstruction was done. Initially diagnosed as a malignant PT, the post-operative pathology revealed a co-existence of malignant PT and MMSCC, an extremely rare finding. This case reports the unique challenge of a patient harboring both malignant PT and MMSCC within the same breast tissue. This exceedingly rare co-existence emphasizes the diagnostic complexities associated with uncommon breast malignancies. Our case highlights the challenges of diagnosing and managing uncommon and aggressive breast malignancies.

Immunohistochemistry in the Diagnosis and Classification of Breast Tumors

CONTEXT.—

In the clinical practice of breast pathology, immunohistochemistry (IHC) of different markers is widely used for the diagnosis and classification of breast lesions.

OBJECTIVE.—

To provide an overview of currently used and recently identified IHC stains that have been implemented in the field of diagnostic breast pathology.

DATA SOURCES.—

Data were obtained from literature review and clinical experience of the authors as breast pathologists.

CONCLUSIONS.—

In the current review, we summarize the common uses of IHC stains for diagnosing different types of breast lesions, especially invasive and noninvasive breast lesions, and benign and malignant spindle cell lesions. In addition, the cutting-edge knowledge of diagnostic carcinoma markers will lead us to further understand the different types of breast carcinoma and differentiate breast carcinomas from other carcinomas of similar morphology. Knowing the strengths and limitations of these markers is essential to the clinical practice of breast pathology.

Comparison of nomogram with random survival forest for prediction of survival in patients with spindle cell carcinoma

Purpose

Spindle cell carcinoma (SpCC) is a relatively rare tumor with an unfavorable prognosis. This study aimed to develop and validate a prediction model for the individual survival of patients with SpCC using Cox regression and the random survival forest (RSF) model.

Methods

Patients diagnosed with SpCC between 2004 and 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database, and randomly divided into training and validating cohorts. Cox regression and RSF were used to identify prognostic predictors and build prediction models. A nomogram based on Cox regression was constructed to predict the 1-, 3-, and 5-year survival of patients with SpCC. Internal validation was conducted using the bootstrapping method. We evaluated the discrimination accuracy and calibration of the model using Harrell's C-index and calibration plot, respectively.

Results

Two hundred and fifty patients diagnosed with SpCC with required information were enrolled in this study. Multivariate Cox regression and RSF identified age, primary site, grade, SEER stage, tumor size, and treatment as significant prognostic predictors of SpCC. The bootstrapped and validated C-indices were 0.812 and 0.783 for nomogram, and 0.790 and 0.768 for RSF, respectively. Calibration plot of the nomogram showed an agreement between the prediction and actual observation.

Conclusions

The nomogram developed in this study is a promising tool with a simplified presentation that can easily be used and interpreted by clinicians for evaluating the survival of each patient with SpCC; its performance was comparable to that of RSF. Application of such models are needed to help oncologists identify the high-risk patients and improve clinical decision making of SpCC treatment.

High-Grade Spindle Cell Lesions of the Breast: Key Pathologic and Clinical Updates

Most of the high-grade spindle cell lesions of the breast are malignant phyllodes tumors (MPTs), spindle cell carcinomas (SpCCs), and matrix-producing metaplastic breast carcinomas (MP-MBCs). MPTs have neoplastic spindle stromal cells and a classic leaf-like architecture with subepithelial stromal condensation. MPTs are often positive for CD34, CD117, and bcl-2 and are associated with MED12, TERT, and RARA mutations. SpCCs and MP-MBCs are high-grade metaplastic carcinomas, whereas neoplastic epithelial cells become spindled or show heterologous mesenchymal differentiation, respectively. The expression of epithelial markers must be evaluated to make a diagnosis. SAS, or rare metastatic spindle cell tumors, are seen in the breast, and clinical history is the best supporting evidence. Surgical resection is the standard of care.

Clinicopathological Examination of Metaplastic Spindle Cell Carcinoma of the Breast: Case Series

Background:

Spindle cell carcinoma (SpCC) of the breast is a rare histological type, a subtype of metaplastic carcinoma characterized by atypical spindle cell and epithelial carcinoma. The proportions of the spindle cell and epithelial components vary among tumours. Due to its rarity, biological characteristics of this disease have been poorly studied.

Methods:

In total, 10 patients with SpCC were surgically treated at our institution from January 2007 to December 2018. We retrospectively investigated these SpCC cases, focusing on the differences between spindle cell and epithelial components. Microsatellite status was also examined.

Results:

Nine cases were triple-negative breast cancer (TNBC). The rates of high tumour grade were 70% in spindle cell components and 56% in epithelial components (P = .65), while the mean Ki67 labelling index were 63% and 58%, respectively (P = .71). Mean programmed death ligand 1 (PD-L1) expression in these components was 11% and 1%, respectively (P = .20). All 10 tumours were microsatellite stable. Patient outcomes of triple-negative SpCC did not differ from those of propensity-matched patients with conventional TNBC.

Conclusions:

Spindle cell components showed higher values in factors examined, although there was no statistically significant difference. Our data reveal that these 2 components of SpCC may be of different biological nature.

Clinicopathologic and genetic features of metaplastic breast cancer with osseous differentiation: a series of 6 cases

AIMS

Metaplastic breast cancer (MBC) comprises a heterogeneous group of tumors, of which MBC with osseous differentiation (MBC-OD) is extremely rare that only few cases have been reported. This study aimed to present the clinicopathologic and molecular features of MBC-OD.

METHODS

We collected 6 cases of MBC-OD from five different centers and described its clinicopathologic and molecular characteristics based on the next-generation sequencing. Another 11 cases from the literature were also reviewed to better characterize the tumor.

RESULTS

The tumor primarily showed an osteosarcoma-like appearance, which composed of high cellularity with spindle cells and osteoblast-like cells producing coarse lace-like neoplastic bone (4/6) or osteoid matrix (6/6). 55 somatic mutations including 39 missenses (70.9%), 9 frameshifts (16.4%), 3 splice sites (5.5%), 3 in-frame InDels (5.5%) and 1 nonsense (1.8%) were identified. TP53 was the most frequently mutated genes (5/6, 83.3%), followed by RB1 (3/6, 50.0%), BCOR (2/6, 33.3%), MED12 (2/6, 33.3%), PIK3CA (2/6, 33.3%), and TET2 (2/6, 33.3%). Genetic alterations suggesting therapies with clinical benefit, including mTOR inhibitors, tyrosine kinase inhibitors (TKI), and poly-ADP ribose polymerase inhibitor (PARPi), were observed in five cases. The median follow-up was 21 months (range, 3-80 months). Local recurrence was observed in two cases and three patients displayed distant metastasis. Two patients died of the disease at 3 months and 7 months, respectively.

CONCLUSIONS

Based on this series, MBC-OD is a highly aggressive breast tumor with osteosarcoma-like morphology and a high incidence of recurrent disease showing specific genetic profiles.

Rare Tumor-Normal Matched Whole Exome Sequencing Identifies Novel Genomic Pathogenic Germline and Somatic Aberrations

Whole exome sequencing (WES) of matched tumor-normal pairs in rare tumors has the potential to identify genome-wide mutations and copy number alterations (CNAs). We evaluated 27 rare cancer patients with tumor-normal matching by WES and tumor-only next generation sequencing (NGS) as a comparator. Our goal was to: 1) identify known and novel variants and CNAs in rare cancers with comparison to common cancers; 2) examine differences between germline and somatic variants and how that functionally impacts rare tumors; 3) detect and characterize alleles in biologically relevant genes-pathways that may be of clinical importance but not represented in classical cancer genes. We identified 3343 germline single nucleotide variants (SNVs) and small indel variants-1670 in oncogenes and 1673 in tumor suppressor genes-generating an average of 124 germline variants/case. The number of somatic SNVs and small indels detected in all cases was 523:306 in oncogenes and 217 in tumor suppressor genes. Of the germline variants, six were identified to be pathogenic or likely pathogenic. In the 27 analyzed rare cancer cases, CNAs are variable depending on tumor type, germline pathogenic variants are more common. Cell fate pathway mutations (e.g., Hippo, Notch, Wnt) dominate pathogenesis and double hit (mutation + CNV) represent ~18% cases.

Spindle cell carcinoma of the breast - A case report

Spindle cell carcinoma (SpCC) of the breast is quite a rare modality classified to the metaplastic carcinoma of the breast. Regarding its biological behavior and the prognosis of the patients with this rare tumor, it has been remaining controversial. We herein report an 88 year-old woman who had a huge bleeding tumor on the right breast. She was a high-aged woman with low activities of daily life, even with some suspicion of distant organ metastasis. While the tumor proved to drastically bleed due to the tumor disintegration, a right simple mastectomy was performed. According to the histopathologic examinations, sarcomatoid spindle cells with severe atypia were observed. By an immunohistochemical examination, the tumor had proved to express neither estrogen receptor, progesterone receptor nor HER2 receptor. Moreover an immunohistochemical expression of AE1/3 and CAM5.2, defining an epithelial neoplasm were observed in addition to an expression of vimentin. From these findings, this bleeding tumor was diagnosed as spindle cell carcinoma of the breast. J. Med. Invest. 67 : 365-367, August, 2020.

Comparative prognostic analysis for triple-negative breast cancer with metaplastic and invasive ductal carcinoma

AIMS

Triple-negative breast cancer comprises different histological subtypes, including metaplastic breast cancer (MBC) and ductal carcinomas (IDCs). The purpose of this study was to compare triple-negative MBC (TN-MBC) with triple-negative IDC (TN-IDC) in terms of survival and predictive factors.

METHODS

With access to the Surveillance, Epidemiology and End Result (SEER) database, a total of 19 383 patients met the eligibility criteria. Clinicopathological characteristics were compared between groups using the χ² test. Univariate and multivariate analyses were applied to evaluate the disease-specific survival (DSS) and overall survival (OS). Subgroup analyses summarised the hazard ratios of TN-MBC versus TN-IDC using a forest plot.

RESULTS

A total of 586 patients with TN-MBC and 18 797 with TN-IDC were included in this study. Patients with TN-MBC were older and presented with larger tumour sizes, relatively rare lymph node positive disease, and had received more chemotherapy. Compared with TN-IDC, the TN-MBC group showed a significantly poorer prognosis before and after the 1:3 matched case-control analysis. Further subgroup analysis indicated that patients with TN-MBC were older, were from specific races, and those with distant metastasis and not receiving radiotherapy had worse prognosis than patients with TN-IDC in terms of DFS and OS.

CONCLUSION

Our results showed that patients with TN-MBC had unique clinicopathological characteristics and poorer prognostic subtype compared with TN-IDC. This improves our understanding of the clinicopathological and prognostic features of this rare entity but also provides more convincing therapeutic guidelines for TN-MBC in patients with breast cancer.

Debilitating Metastatic Spindle Cell Carcinoma of the Breast

Spindle cell carcinoma of the breast is a rare malignancy. If diagnosed and treated in a timely manner, it is generally associated with a good prognosis. Herein, we have presented an interesting case of metastatic spindle cell carcinoma of breast origin, with extensive metastasis and an unusually aggressive disease course. We also discussed refractory hypoglycemia as a fatal complication of highly metabolically active malignancy. Lastly, we briefly explored the importance of seeking medical attention for early detection and treatment and the need to address psychosocial barriers that influence breast cancer screening.

TiHo-0906: a new feline mammary cancer cell line with molecular, morphological, and immunocytological characteristics of epithelial to mesenchymal transition

Feline mammary carcinomas (FMCs) with anaplastic and malignant spindle cells histologically resemble the human metaplastic breast carcinoma (hMBC), spindle-cell subtype. hMBCs display epithelial-to-mesenchymal transition (EMT) characteristics. Herein we report the establishment and characterization of a cell line (TiHoCMglAdcar0906; TiHo-0906) exhibiting EMT-like properties derived from an FMC with anaplastic and malignant spindle cells. Copy-number variations (CNVs) by next-generation sequencing and immunohistochemical characteristics of the cell line and the tumour were compared. The absolute qPCR expression of EMT-related markers HMGA2 and CD44 was determined. The growth, migration, and sensitivity to doxorubicin were assessed. TiHo-0906 CNVs affect several genomic regions harbouring known EMT-, breast cancer-, and hMBCs-associated genes as AKT1, GATA3, CCND2, CDK4, ZEB1, KRAS, HMGA2, ESRP1, MTDH, YWHAZ, and MYC. Most of them were located in amplified regions of feline chromosomes (FCAs) B4 and F2. TiHo-0906 cells displayed an epithelial/mesenchymal phenotype, and high HMGA2 and CD44 expression. Growth and migration remained comparable during subculturing. Low-passaged cells were two-fold more resistant to doxorubicin than high-passaged cells (IC50: 99.97 nM, and 41.22 nM, respectively). The TiHo-0906 cell line was derived from a poorly differentiated cellular subpopulation of the tumour consistently displaying EMT traits. The cell line presents excellent opportunities for studying EMT on FMCs.

Spindle cell carcinoma: the general demographics, basic clinico-pathologic characteristics, treatment, outcome and prognostic factors

Background

Owing to the rarity, the general demographics, basic clinico-pathologic features, management, outcome and prognostic factors of spindle cell carcinoma (SpCC) were unexplored.

Methods

A SEER analysis was performed with 2336 cases (1973-2016).

Results

A peak incidence occurred at 70~80 years without any gender predominance and 83.13% occurred in white people. The respiratory system was mostly affected tumor site (35%). Significant overall survival (OS) and disease specific survival (DSS) were found differentiated in gender, age, marital status, primary tumor location, AJCC stage, T stage, N stage, M stage, pathologic grade and treatment modality. In the multivariate Cox model, the age > 69 years (Hazard ratio [HR] = 1.427 for OS, P = 0.01 and HR = 1.491 for DSS, P = 0.003; Reference [Ref] age ≤ 69 years), tumor location in respiratory system (HR = 1.550 for OS, P = 0.041 and HR = 1.561 for DSS, P = 0.04; Ref: digestive system), N2 stage (HR = 1.962 for OS, P = 0.006 and HR = 1.982 for DSS, P = 0.004; Ref: N0 stage) and AJCC stage IV (HR = 4.601 for OS, P = 0.000 and HR = 5.107 for DSS, P = 0.000; Ref: stage I) were independently associated with worse OS and DSS.

Conclusions

SpCC mostly occurred in white people at 70~80 years old without predominance in any gender. The respiratory system was mostly affected site. The patient's age, primary tumor location, AJCC stage were independent prognostic indicators for both DSS and OS of SpCC.

Development of ipsilateral chest wall spindle cell carcinoma in a patient with invasive ductal breast carcinoma during postoperative adjuvant therapy: A case report

RATIONALE

Metaplastic breast carcinoma (MBC) is rare subtype of breast carcinoma and is regarded as ductal carcinoma that undergoes metaplasia into a glandular growth pattern. Spindle cell carcinoma (SPC) is a subtype of MBC with a predominant spindle cell component.

PATIENT CONCERNS

The patient was a 52-year-old female with invasive ductal breast carcinoma who underwent a modified radical mastectomy and an axillary node dissection. A new lump was observed underneath the surgical site between the pectoralis major and pectoralis minor muscles 45 days after the patient underwent sequential postoperative chemotherapy and radiotherapy.

DIAGNOSES

It was speculated that the new lesion had developed during postoperative adjuvant therapy. And the new lesion was regarded as a recurrence.

INTERVENTIONS

We performed a wide dissection of the tumor with negative margins. The pathology of the tumor indicated SPC. Then, the patient received chemotherapy and demonstrated a poor response.

OUTCOMES

Local recurrence and pulmonary metastasis developed shortly afterwards, and the patient succumbed to the disease within 5 months.

LESSONS

Local recurrence with metaplastic SPC transformed from invasive ductal breast carcinoma during postoperative chemotherapy and radiotherapy is rare. The failure of subsequent chemotherapy and the progression of disease indicate the aggressive nature of SPC and its decreased sensitivity to chemotherapy and radiotherapy. Further studies must be performed to improve the prognosis of these patients.

Rare variant of metaplastic carcinoma of the breast: a case report and review of the literature

Background

Metaplastic carcinoma encompasses a group of neoplasms characterized by differentiation of the neoplastic epithelium into squamous cells and/or mesenchymal-looking elements. Spindle cell carcinoma is a rare variant of this special histological type. Its prognosis remains poor, with a high rate of local recurrence and distant metastasis. To date, only a small number of cases have been described. There is no clear agreement on this histological subtype.

Case presentation

We report a case of a 53-year-old Moroccan woman who consulted our institution following palpation of a nodule of the left breast. Mammography in combination with breast ultrasonography revealed a lesion classified as Breast Imaging Reporting and Data System 4 with microcalcification. The patient was diagnosed with spindle cell carcinoma of the breast. The diagnosis was based primarily on histological and immunohistochemical studies of the breast biopsy and secondarily on the surgical specimen. No local or distant metastasis was found. The treatment used was total surgical excision followed by radiotherapy.

Conclusions

We describe the features (epidemiological, clinical, histological, immunohistochemical, and therapeutic outcomes) of our patient’s case and compare them with literature data.

Differential expression and clinical significance of epithelial-mesenchymal transition markers among different histological types of triple-negative breast cancer

Background: Triple-negative breast cancer (TNBC) is a heterogeneous disease closely associated with epithelial-to-mesenchymal transition (EMT). This study aimed to investigate the role of EMT in metaplastic carcinoma.

Methods: E-cadherin, Slug, Twist and Vimentin levels were detected by immunohistochemistry in 167 TNBC tumors, including 145 invasive carcinomas of no special type (ICONSTs), 14 spindle cell carcinomas (SpCCs) and 8 matrix-producing carcinomas (MPCs).

Results: Nuclear Slug and Twist were more frequently detected in SpCC and MPC tumors than that in ICONST tumors (p<0.001). The rate of E-cadherin loss was much lower in the ICONST tumors than that in the SpCC and MPC tumors (p<0.001). Vimentin was expressed in all SpCC and MPC tumors. Furthermore, nuclear expression of Slug and Twist was positively associated with the cytoplasmic localization of Vimentin (p<0.001) and was inversely associated with membranous staining of E-cadherin (p<0.001). These trends were more apparent in the SpCC and MPC tumors than in the ICONST tumors. Follow-up data were available for 151 patients. The follow-up times ranged from 1 month to 11 years (mean: 74 m; median: 21 m). The median progression-free survival and overall survival times were 24 months (mean: 32 months) and 22 months (mean: 35 months), respectively. Tumor size, TNM stage and E-cadherin were found to be independent prognostic factors of TNBC.

Conclusions: EMT may play an important role in TNBC, especially in MPC and SpCC. Further researches are needed to confirm this finding. The results of this study may facilitate the future development of targeted therapies based on alterations in the EMT and stem cell markers.

Analysis of Contractility and Invasion Potential of Two Canine Mammary Tumor Cell Lines

Cancer cells are surrounded by a mechanically and biochemically distinct microenvironment that undergoes dynamic changes throughout the neoplastic progression. During this progression, some cancer cells acquire abnormal characteristics that potentiate their escape from the primary tumor site, to establish secondary tumors in distant organs. Recent studies with several human cancer cell lines have shown that the altered physical properties of tumor cells, such as their ability to apply high traction forces to the surroundings, are directly linked with their potential to invade and metastasize. To test the hypothetical interconnection between actomyosin-mediated traction forces and invasion potential within 3D-microenvironment, we utilized two canine mammary tumor cell lines with different contractile properties. These cell lines, canine mammary tumor (CMT)-U27 and CMT-U309, were found to have distinct expression patterns of lineage-specific markers and organization of actin-based structures. In particular, CMT-U309 carcinoma cells were typified by thick contractile actomyosin bundles that exerted high forces to their environment, as measured by traction force microscopy. These high contractile forces also correlated with the prominent invasiveness of the CMT-U309 cell line. Furthermore, we found high contractility and 3D-invasion potential to be dependent on the activity of 5′AMP-activated protein kinase (AMPK), as blocking AMPK signaling was found to reverse both of these features. Taken together, our findings implicate that actomyosin forces correlate with the invasion potential of the studied cell lines.

Spindle cell carcinoma of the esophagus: A multicenter analysis in comparison with typical squamous cell carcinoma

This study conducted a retrospective multicenter analysis to investigate the clinicopathological features, optimal therapeutic strategy, and prognosis of spindle cell carcinoma (SpCC) of the esophagus.A total of 71 patients with esophageal SpCC from 3 large cancer centers in China were systematically analyzed. All patients received curative resection, 13 patients received adjuvant radiotherapy and 15 patients received adjuvant combination chemotherapy. Additionally, a total of 1852 patients with typical esophageal SCC (SCC) were selected as controls in this study.SpCC mostly presented as a polypoid appearance (66.2%), and the surrounding mucosa showed high-grade hyperplasia or superficial SCC in 31 cases (43.7%). Two patients even had extensive carcinoma in situ that spread to the resection margins. Patients in the SpCC group were more likely to present with stage I lesions compared with those in the typical SCC group (33.8% vs 8.0%, P < 0.001). Although the percentage of T1/2 lesions was higher in the SpCC group than in the typical SCC group (67.6% vs 29.7%, P < 0.001), both groups had similar rates of locoregional lymphatic metastases (45.1% vs 48.4%, P = 0.578). The median survival time and 5-year overall survival of the SpCC group was 43 months and 44.8%, respectively, higher than 37.5 months and 38.3%, respectively, for the typical SCC group (P = 0.044). In univariate analysis, the macroscopical type and pathological T, N, and TNM stages had a statistically significant impact on the prognosis of SpCC after curative resection. However, only the TNM stage (hazard ratio, 2.708; 95% confidence interval, 1.786-4.105, P < 0.001) was identified as an independent prognostic factor in multivariate analysis. The 5-year OS of SpCC in stages I (79.8%) and II (39.7%) were significantly longer than that of stages III/IV (16.2%) (P < 0.001 and P = 0.012). As those SpCC cases that received chemoradiotherapy were in more advanced stages, their prognosis was still worse than SpCC patients who did not receive chemoradiotherapy even after such treatment (P = 0.042, 0.010, respectively).SpCC shows a highly aggressive tendency of lymphatic spread, although it does not tend to infiltrate deeply into the esophageal wall. Compared with typical SCC that also underwent esophagectomy with extended lymphadenectomy, SpCC may achieve a better survival rate. Further investigation is warranted to examine the effect of postoperative chemoradiotherapy on the prognosis of SpCC.