Metaplastic Squamous Cell Research Articles

Metaplastic Squamous Cell Carcinoma - A Very Rare Entity of Breast Carcinoma in an Elderly Female Patient

Metaplastic squamous cell carcinoma of breast is a rare malignancy and accounts to < 1% of all breast cancers and it is most commonly seen in elderly women. As the tumor cells exhibit heterogeneous behavior, a standard therapeutic approach is difficult to establish. Age, size of the tumor, lymph node metastasis and receptor status are the important prognostic factors. Metaplastic squamous cell carcinoma has very unfavorable prognosis compared to other triple negative breast malignancies. Surgery combined with neoadjuvant radiotherapy can ameliorate the disease outcome. Early diagnosis and treatment play a crucial role in the management. Here we report a case of metaplastic squamous cell carcinoma of breast in a 67 years female who came with breast lump in the left breast for 6 months with palpable axillary lymph nodes. She underwent modified radical mastectomy with the diagnosis of Ductal cell carcinoma reported on fine needle aspiration cytology. Lymph node clearance done at all levels and the specimen was sent for histopathological examination. Gross examination revealed unifocal gray white irregular tumor measuring 9 x 4 x 3.6 cms located in the inner central quadrant and container labelled as level 1 revealed 7x 4 x 3 cms firm mass. Microscopic examination revealed infiltrating tumor tissue in nesting pattern, syncytial pattern and solid pattern. The tumor cells were having pleomorphic nuclei, increased N:C ratio and moderate to scant eosinophilic cytoplasm. Within the nesting pattern of tumor tissue keratin pearls were seen. Interstitium showed lymphocytic infiltration. One lymph node from level 1 showed metastatic deposits. The tumor was diagnosed as metaplastic Squamous cell carcinoma of left breast with TNM staging of PT3 N1 Mx. Keywords: Squamous, metaplastic, breast, poor prognosis.

Genetic analysis of low-grade adenosquamous carcinoma of the breast progressing to high-grade metaplastic carcinoma

PurposeLow-grade adenosquamous carcinoma (LGASC) is a rare type of metaplastic carcinoma of the breast (MBC) with an indolent clinical course. A few LGASC cases with high-grade transformation have been reported; however, the genetics underlying malignant progression of LGASC remain unclear.MethodsWe performed whole-genome sequencing analysis on five MBCs from four patients, including one case with matching primary LGASC and a lymph node metastatic tumor consisting of high-grade MBC with a predominant metaplastic squamous cell carcinoma component (MSC) that progressed from LGASC and three cases of independent de novo MSC.ResultsUnlike de novo MSC, LGASC and its associated MSC showed no TP53 mutation and tended to contain fewer structural variants than de novo MSC. Both LGASC and its associated MSC harbored the common GNAS c.C2530T:p.Arg844Cys mutation, which was more frequently detected in the cancer cell fraction of MSC. MSC associated with LGASC showed additional pathogenic deletions of multiple tumor-suppressor genes, such as KMT2D and BTG1. Copy number analysis revealed potential 18q loss of heterozygosity in both LGASC and associated MSC. The frequency of SMAD4::DCC fusion due to deletions increased with progression to MSC; however, chimeric proteins were not detected. SMAD4 protein expression was already decreased at the LGASC stage due to unknown mechanisms.ConclusionNot only LGASC but also its associated high-grade MBC may be genetically different from de novo high-grade MBC. Progression from LGASC to high-grade MBC may involve the concentration of driver mutations caused by clonal selection and inactivation of tumor-suppressor genes.

Metaplastic squamous cell carcinoma of the breast – A rare case report

Metaplastic carcinomas of the breast are unusual conditions and account for 0.25% to 1% of annual breast malignancies. Among these, primary metaplastic squamous cell carcinoma (SCC) of the breast is an extremely rare entity occurring in less than 0.1% of all breast carcinomas. Management protocol and survival outcome for metaplastic breast carcinoma is relatively unknown because of the rarity of the disease, but studies suggest that removal of the tumor and adjuvant radiotherapy has the greatest impact. In this paper, we report the occurrence of this rare lesion in a 71-year-old lady who was treated and is recovering uneventfully. Early diagnosis and radical upfront surgery may warrant a good prognosis, as demonstrated in this case report.

Metaplastic squamous cell carcinoma caricaturing as tuberculous mastitis-A vicissitude of clinical diagnostic misadventure

Tuberculous mastitis and invasive breast cancers are known to co-exist or occur in the breast independently of each other, albeit the former being less common in developed countries. Tuberculous mastitis with its clinical presentation and morphological features can caricature invasive breast carcinoma. The overlapping features of tuberculous mastitis and metaplastic squamous cell carcinoma often lead to, if no due clinical diligence and discretion is used, bewildering misinterpretation with the vicissitude of diagnostic implications of tuberculous mastitis ensuing catastrophic and perilous ramifications. A 42-year-old woman presented with exophytic growth with extensive areas of ulceration. Clinically, the lesion was diagnosed as disseminated tuberculous mastitis based on clinical and morphological features, which was surgically resected. On histological examination, the lesion was diagnosed as invasive metaplastic squamous cell carcinoma. Thecase being presented here displays the vagary involved in clinical diagnosis of tuberculous mastitis inasmuch as it often shares clinical and morphological features with a devastatingly perilous variant of invasive duct carcinoma, metaplastic squamous cell carcinoma, the inadvertent eschewing of or misapprehending of which may engender devastating prognostic implications.

The efficacy of gemcitabine combined with immunotherapy in a patient with metastatic metaplastic squamous cell carcinoma of the breast

Abstract Objectives Metaplastic squamous cell carcinoma of the breast is a rare form of breast carcinoma for which there is currently no standard treatment. Case presentation We report the case of a 33-year-old woman with enlargement in her left breast who was diagnosed with metaplastic squamous cell carcinoma by core needle biopsy. The patient underwent a modified radical mastectomy. The immunohistochemistry showed it was a triple-negative breast cancer: progesterone receptor-negative (PR-), estrogen receptor-negative (ER-), and human epidermal growth factor receptor 2 -negative (HER2-). The patient received 6 cycles of adjuvant chemotherapy with nab-paclitaxel and carboplatin. One year later, she developed lung metastases from squamous cell carcinoma. Immunohistochemical results remained triple-negative (ER-, PR- and HER2-). The patient then received gemcitabine combined with immunotherapy. The patient has been assessed as stable disease so far. Conclusions Immunotherapy combined with gemcitabine showed good efficacy in the treatment of metastatic metaplastic squamous cell carcinoma of the breast after nab-paclitaxel combined with platinum-based therapy.

Abstract 1225: the existence, characteristics and underlying regulators of spontaneous epithelial-mesenchymal transition from a monophasic metaplastic squamous carcinoma patient-derived cancer cell model

Abstract Epithelial-mesenchymal transition (EMT) has been considered the mechanism underlying distant metastasis in epithelial cancers. The hallmarks of the EMT phenomenon are mainly the loss of cell-cell adhesion, acquisition of a mesenchymal phenotype, gain of mobility and invasiveness, and attainment of enhanced tumorigenicity and anchorage-independent growth. After EMT, cancer cells can enter and survive in fluid-filled spaces and subsequently colonize distant sites. Despite a huge body of in vitro and in vivo evidence recognizing EMT as an important event in tumor progression, whether EMT exists in naturally-occurring experimental settings remains a contentious debate in the field of pathology. Lack of convincing histopathological evidence of EMT in tumor subtypes without spindle sarcomatous tumor components and lack of dynamic change demonstration of EMT are to blame. In this report, we devised a naturally-occurring experimental setting to prove the existence of EMT in tumors completely lacking histological evidence of EMT. Further, we demonstrated dynamic change of EMT in in vitro and in vivo settings. We performed primary culture 37H from a monophasic metaplastic squamous cell carcinoma tissue (MMSCC), which exhibited no histologic features reminiscent of EMT, to examine whether EMT exists in tumors without sarcomatous histology. Two dominant subtypes demonstrating different morphology were derived from parental 37H: polygonal epithelial-type (HE) and epithelioid mesenchymal-type (HM) cells. The HE cells were E-cadherin+vimentin- predominant; while the HM cells were E-cadherin-vimentin+ predominant, and functionally concomitant with increased migration and invasion and anchorage-independent tumorigenicity. Taking advantage of the inherited differences between the HE and HM cells, we performed head-to-head comparison by RNA-seq and subsequently identified key EMT transcription factors (EMT-TFs) ZEB1 and ZEB2 in this naturally-occurring experimental setting. In the primary MMSCC tissue where 37H was derived, the upregulation of ZEB1 and ZEB2 was also observed in vimentin+ carcinoma cells. Further, the dynamic change of EMT was demonstrated in the HE and HM cells in in vitro and in vivo settings. Spontaneous EMT was observed specifically in the ZEB1-or ZEB2-overexpressed polygonal epithelial-type cells; the knockdown of ZEB1 and ZEB2 reverted EMT in the HM cells; and reverse EMT was found a requirement for HM cells to grow in a xenograft mouse model. In conclusion, this report backed up the existence of EMT in naturally-occurring tumor without histologic evidence of EMT. The identification of underlying regulators contributing to spontaneous EMT, and the demonstration of EMT dynamic change were also included. Citation Format: Huang-Chun Lien, Hui-Chieh Yu, Tom Wei-Wu Chen, I-Chun Chen, Chiao Lo, Ling-Chun Yeh, Li-Ping Hsiao, Yen-Shen Lu. the existence, characteristics and underlying regulators of spontaneous epithelial-mesenchymal transition from a monophasic metaplastic squamous carcinoma patient-derived cancer cell model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1225.

Abstract P6-14-14: Advancing research on metastatic breast cancer: the UPTIDER post-mortem tissue donation program

Abstract Background. Research in metastatic breast cancer is hampered by limited sample availability. Post-mortem tissue donation programs can help to overcome this problem but are logistically challenging and have thus far mainly focused on histopathological and genomic research. We here present the UPTIDER program (NCT04531696), aimed at the multilevel characterization of advanced breast cancer and generation of tumour models. Patients and Methods. Patients with stage IV breast cancer receiving their last line(s) of treatment are eligible for participation. Blood, urine and saliva samples are collected upon inclusion. Upon death, a post-mortem MRI (when possible) followed by a rapid autopsy is performed. Liquid biopsies from all body fluids and tissue samples from all macroscopically identified metastatic sites are collected. Samples are processed as mirrored biopsies in different conditions, such as fresh frozen for omics analyses, formalin fixed paraffin-embedded for histopathology, and slowly frozen in freezing medium or fresh for generation of xenograft and organoid models. Results. Since approval by the local Ethical Committee in November 2020, 22 patients have been enrolled and 15 autopsies have been performed. Mean interval between death and start of autopsy was 3h (range 2-6h), mean duration of the autopsies was 6h (4-9h). A post-mortem MRI was performed in 6 patients. Peripheral blood, central blood and bone marrow were collected from all patients; urine, ascites, cerebrospinal, pericardial and pleural fluid all in more than 2/3 of patients. On average, 232 (range 90-406) tissue samples of which 164 (45-303) pathological from 42 (15 – 79) metastases were collected for each patient. Most often sampled metastatic sites were lymph nodes, liver, bones, pleura and peritoneum. Samples from the primary tumour could be retrieved from all patients, either during the autopsy (n=6) or from historical archives. In total, 133 tumour samples were sent to collaborating partners for patient-derived xenograft creation. Already some have been successfully established and stored, including models derived from a patient with invasive lobular carcinoma (ILC) and one with metaplastic squamous cell carcinoma. When correlating microscopic and macroscopic findings, patients could largely be divided into three main categories. Eleven patients presented with overt and extensive disease burden, often characterized by diffuse visceral, pleural, peritoneal, bone and lymph node involvement. Two patients, both with ILC, presented with underestimated yet extensive disease burden. While gross examination and cross sectioning of organs did not reveal clear involvement, microscopical invasion of stomach and liver, amongst others, was found. Lastly, limited disease burden was seen in two patients, both with leptomeningeal involvement. In those patients, massive tumoral infiltration in the subarachnoid space and along the blood-brain barrier was seen microscopically, with no grey matter invasion. Conclusion. We successfully launched a new and comprehensive post-mortem tissue donation program for patients with metastatic breast cancer, enrolling ~ 1 patient per month. Post-mortem tumour samples already resulted in successful establishment of some patient-derived xenografts. From a clinical point of view, vast underestimation of the disease extent on imaging during life as well as macroscopically during the autopsy was observed in some patients with metastatic ILC. For patients with leptomeningeal metastasis, we showed that the highly aggressive nature of their disease might be explained by extensive meningeal infiltration disrupting the blood-brain barrier. Further insights into disease progression and heterogeneity will be generated by the ongoing multi-omics analyses. Citation Format: Tatjana Geukens, Maxim De Schepper, Karen Van Baelen, François Richard, Marion Maetens, Amena Mahdami, Ha-Linh Nguyen, Edoardo Isnaldi, Anirudh Pabba, Sophia Leduc, Imane Bachir, Maysam Hajipirloo, Emily Vanden Berghe, Sigrid Hatse, Eleonora Leucci, Maria Francesca Baietti, Georgios Sflomos, Cathrin Brisken, Patrick Derksen, Colinda Scheele, Vincent Vandecaveye, Ann Smeets, Ines Nevelsteen, Kevin Punie, Patrick Neven, Elia Biganzoli, Hans Wildiers, Wouter Van Den Bogaert, Giuseppe Floris, Christine Desmedt. Advancing research on metastatic breast cancer: the UPTIDER post-mortem tissue donation program [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P6-14-14.

Extensive Eccrine Squamous Syringometaplasia Mimicking Squamous Cell Carcinoma on Histopathology

Eccrine Squamous Syringometaplasia (ESSM) is a histologically distinctive skin eruption occurring predominantly in acral or intertriginous areas presenting as erythematous macules, papules or patches. It is a response of eccrine ducts and glands to any injury or inflammation. The cuboidal epithelium of eccrine ducts and glands undergoes metaplasia and transforms to keratinised squamous epithelium in ESSM. Other types of metaplastic changes encountered are squamous, mucinous and adenomatous. In squamous syringometaplasia, the metaplastic squamous cells form lobules and florid types can pose a diagnostic dilemma, which if not well understood may lead to an erroneous diagnosis of neoplasia. Literature suggests ESSM as a condition associated with another pathogenic stimuli or therapy; however florid ESSM is very rare. Hereby, the authors present a case report of a 43- year- old male who presented florid ESSM mimicking well-differentiated Squamous Cell Carcinoma (SCC). The present case presented with a non healing elevated lesion on anterior aspect of right leg with itching. Similar lesions were not present in any other part of the body. The patient did not have history of any systemic disease or drug intake. The lesion was excised and sent for histopathology. On gross examination the skin showed irregular thickening and foci of erosion. Microscopy showed acanthotic, hyperkeratotic epidermis and dermal ESSM. There were irregular clusters of metaplastic squamous cell in dermis, resembling invasive islands of SCC. Meticulous examination revealed lobulated architecture of ESSM, lack of individual cell keratinisation/significant atypia or mitosis. The present report highlights the significance of histopathological diagnosis of benign squamous proliferations which can mimic malignancy and cause undue stress to the patient.

Clinicopathological features and HER2 expression of metaplastic squamous cell carcinoma of the breast

Objective: To investigate the clinicopathological features and HER2 expression of metaplastic squamous cell carcinoma (MSCC) of the breast. Methods: A total of 47 MSCC cases diagnosed in the Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China from January 2010 to December 2021 were reviewed. The clinical information (including the follow-up data of HER2 positive patients) and pathological features were collected and analyzed. Results: All of the patients were female. Among the 47 cases, 25 were pure squamous cell carcinoma (PSCC) and 22 were mixed metaplastic carcinoma with squamous cell component (MMSC). The median age of the patients was 54 years (range, 29-84 years). The maximum diameter of the mass ranged from 0.8 to 10.0 cm, with a mean value of 3.3 cm, 85.7% (24/28) of the cases were smaller than 5 cm, and only 4 cases were larger than or equal to 5 cm. 89.5% of the MMSC presented with a solid mass. Cystic changes were more commonly found in the PSCC group (50%, P<0.05) than the MMSC group. 36.7% (11/30) of the patients had lymph node metastasis at the time of diagnosis. The squamous cell carcinoma component in all cases showed diffuse or patchy expression of p63, p40 and CK5/6. 55.3% (26/47) of the cases showed triple-negative phenotype. Among the 7 HER2-positive patients, 6 were MMSC group, which had a significantly higher rate of HER2-positivity than that in the PSCC group (1 case). In 1 MMSC case, immunohistochemistry showed HER2 2+in the invasive ductal carcinoma component and HER2 negativity (0) in the squamous cell carcinoma component, but HER2 FISH was negative in invasive ductal carcinoma and positive in squamous cell carcinoma component. Six HER2-positive MSCC patients received anti-HER2-targeted therapy, including two patients who received neoadjuvant chemotherapy combined with anti-HER2-targeted therapy before surgery. One patient achieved pathological complete remission, while the other achieved partial remission (the residual tumors were squamous cell carcinoma components). After 9-26 months of follow-up, four patients had no disease progression, two patients developed pulmonary metastases, and one patient showed local recurrence. Conclusions: MSCC is a group of heterogeneous diseases. PSCC and MMSC may be two different entities. Most of the MSCC are triple-negative and HER2 positivity is more commonly seen in MMSC with invasive ductal carcinoma component. Some HER2-positive MSCC patients can achieve complete remission or long-term progression-free survival after receiving anti-HER2 targeted therapy, but the squamous cell carcinoma component may be less sensitive to targeted therapy than the invasive ductal carcinoma component.

Sonographic and pathological features of metaplastic squamous cell carcinoma of the breast: a case series

ObjectiveThe aim of this study was to evaluate the sonographic features and to compare the sonographic findings with the pathologic features.MethodsThe sonographic and pathological features of all patients were retrospectively reviewed.ResultsAll these 9 patients presented with a palpable breast mass first found by the patient before presentation. The median diameters were 3.67 cm. On two-dimensional imaging, 8 masses showed mixed echogenicity with both solid and cystic components, and only 1 mass showed hypoechoic. All the masses had irregular shapes. 1 mass had indistinct margin and 8 masses had microlobulated margins. Calcifications was seen in 1 mass. On color Doppler flow imaging, 8 masses had high vascularity with high resistance index; 5 masses had grade III blood flow signal; 3 masses had grade II blood flow signal. On histopathological examination, 5 masses were adenocarcinoma with squamous metaplasia, and 4 masses were pure SCC. On immunohistochemical staining, estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth factor receptor (HER2) were negative in 5 masses. There were 2 patients with lymph node metastasis.ConclusionsMost of the sonographic features of MSCC were mixed echogenicity with central cystic components, posterior echo enhancement, abundant vascularity with high resistance.

Clinicopathologic characteristics of HER2-positive metaplastic squamous cell carcinoma of the breast

AimsThe aim of this study was to analyse the clinicopathological features and prognosis of human epidermal growth factor receptor-2 (HER2)-positive metaplastic squamous cell carcinoma (MSCC).MethodsFifty-eight patients with MSCC of the...

SOX10 - A Novel Marker for the Differential Diagnosis of Breast Metaplastic Squamous Cell Carcinoma.

IntroductionDifferential diagnosis of metaplastic squamous cell carcinoma of breast (MSCCB) is difficult. In particular, in terms of metastatic MSCCB, because of the low speciality of traditional markers such as mammaglobin, gross cystic disease fluid protein-15 (GCDFP-15) and GATA binding protein 3 (GATA3), the most common problem is differentiating the spread of MSCCB to the lung from a primary lung squamous cell carcinoma. It is urgently required to explore a novel marker to aid in differential diagnosis.AimThe aim of this study is to explore a novel marker to aid in the differential diagnosis of MSCCB from other squamous cell carcinomas (SCC) in other organs.MethodsWe tested the expression of SOX10 in 375 human SCC specimens with immunohistochemistry (IHC).ResultsIn a series of 20 MSCCB, 9 (45%) were positive for SOX10. All of them were triple-negative MSCCB. Conversely, SOX10 was totally negative in another 205 SCC originating from lung, skin, cervix, oral mucosa, and esophagus. In a series of 150 triple-negative breast cancer and their metastatic foci, SOX10 labeling in the primary tumor and metastasis was 78% and 79.3%, respectively, and the agreement rate was 97.3% (P>0.05).ConclusionOur findings demonstrate that SOX10 was recommended for differentiating MSCCB from non-mammary metastasis to the breast, as well as for distinguishing primary SCC from metastatic MSCCB, and SOX10 may be valuable in the pathological diagnosis of breast-derived metaplastic squamous cell carcinoma.

Soft Tissue Special Issue: Cutaneous Pleomorphic Spindle Cell Tumors.

This manuscript provides an overview of pleomorphic spindle cell tumors presenting on sun-damaged skin of the elderly and includes discussions of atypical fibroxanthoma, pleomorphic dermal sarcoma, spindle cell and metaplastic squamous cell carcinoma, spindle cell and dedifferentiated melanoma and poorly differentiated cutaneous angiosarcoma. These tumors share many of the clinical presenting and histological features, making confident diagnosis challenging. A reliable and robust diagnosis is necessary to predict behavior as the biologic potential of these tumors ranges from benign (e.g. atypical fibroxanthoma) to outright malignant with poor survival rates (e.g. cutaneous angiosarcoma). The salient clinical, histologic and immunohistochemical characteristics are discussed in detail with emphasis on distinguishing features and differential diagnosis to provide the reader with a better understanding of these entities and helpful clues for a more robust diagnosis.

THE EFFECTIVENESS OF THE COMBINATIONS OF CALCITRIOL AND ETHYNIL ETHYL ESTRADIOL TO DECREASE OSTEOPOROSIS AND ENDOMETRIAL CANCER RISKS IN OVARIECTOMIZED RATS

The objective of this research was to study the effectiveness of calcitriol and ethynil ethyl estradiol combinations to decrease osteoporosis and endometrial cancer risks in ovariectomized Wistar rats. Twenty five 8-week old female Wistar rats were randomly divided into five groups (normal controlled rats/NK, ovariectomized rats/OVK, ovariectomized rats + calcitriol supplementation/OVD, ovariectomized rats + ethynil ethyl estradiol supplementation/OVE, and ovariectomized rats + calcitriol + ethynil ethyl estradiol supplementation/OVDE). At the end of the study, all rats were weighed and euthanized with 10% ketamine and 2% xylazine. Uterus and left femur were taken and fixed in 10% formaldehyde solution for histopathological examination using hematoxylin and eosin stain. Uterus was weighed before the fixation. The results showed that the percentage of uterus weight in OVK was significantly decreased compared to NK. Meanwhile, the percentage of uterus weight in OVDE was significantly increased compared to OVK. Histopathological features of the uterus in OVK were atrophy, reduction of myometrial and endometrial layers thickness, and formation of cuboidal epithelium in the endometrial lumen. However, the thickness of myometrial and endometrial layers in OVDE were increased, and its endometrial lumen was lined with metaplastic and hyperplastic squamous cell. Histopathological features of distal femur epiphysis in OVK ras showed fewer trabecular spiculums and more adipocyte in the bone marrow compared to NK. However, OVDE had more trabecular bone spiculum and less adipocyte in the bone marrow compared to OVK. In conclusion, the combination of calcitriol and ethynil ethyl estradiol supplementation could reduce osteoporosis, but increased the endometrial cancer risk in ovariectomized Wistar rats.

Cytogenetic analysis of metaplastic squamous cell carcinoma of the breast inter- and intratumoral heterogeneity.

Squamous cell carcinoma (SCC) of the breast is a rare and generally aggressive disease that accounts for less than 0.1% of all breast carcinomas. Although SCCs have distinct morphological features, their origin and cytogenetic profile are not well understood. Five patients with SCC were studied. The tumor area that was predominantly composed of SCC components was macrodissected and DNA was extracted. In three cases, an invasive or noninvasive ductal carcinoma of no special type (NST) component was also present. NST-component DNA was also extracted. The tumor DNA was used for array comparative genomic hybridization analysis using a high-density oligonucleotide microarray. The cytogenetic profile of the SCC components was compared with each other and with the paired NST component in three of the five cases. The cytogenetic profile of the SCC components indicated large intertumoral heterogeneity. There were between 2 and 160 copy number alterations per case, and no common copy number alterations were identified. The cytogenetic profiles of the paired SCC and NST components were similar but not identical. Although, in one case, a larger number of copy number aberrant regions were detected in the SCC component than the NST component. In this case, all the NST component aberrations were present in the SCC component. This implies that the SCC component originated from the NST component. There were no common SCC component-specific aberrations in the three NST-component cases. Our results demonstrate the cytogenetic inter- and intratumoral heterogeneity of SCC of the breast. Our comparison of cytogenetic profiles indicated that the SCC component originated from the NST component in one case.

Metastatic metaplastic breast carcinoma mimicking pulmonary squamous cell carcinoma on fine-needle aspiration.

Metaplastic squamous cell carcinoma (SCC) of the breast is a rare type of breast cancer. Metastases to the lung, which can be a major site of second primary tumor development among breast cancer patients, are difficult to distinguish from primary SCC of the lung and present a unique challenge for pathologists. There are few available discriminating immunohistochemical markers as squamous differentiation typically leads to loss of expression of characteristic primary epithelial cell markers of both breast and lung origin. GATA protein binding 3 (GATA-3) is a useful marker of breast origin in metastatic ductal and lobular carcinomas including poorly differentiated triple-negative carcinomas and some metaplastic carcinomas. Here, we present a case of metastatic SCC presenting as a solitary lung mass with regional lymph node metastases and a single satellite lesion in a patient with a history of metaplastic SCC of the breast. In addition to the routine markers of squamous differentiation, the metastases were also positive for estrogen receptor (ER) and GATA-3 on cytologic material obtained by transbronchial FNA. This suggests that immunoreactivity for ER and GATA-3 may support a diagnosis of metastatic SCC in the context of a prior metaplastic SCC of the breast.

AIRP Best Cases in Radiologic-Pathologic Correlation: Metaplastic Squamous Cell Carcinoma of the Breast

AIRP Best Cases in Radiologic-Pathologic Correlation: Metaplastic Squamous Cell Carcinoma of the Breast

Clinicopathological analysis of ten patients with metaplastic squamous cell carcinoma of the breast

Primary squamous cell carcinoma (SCC) and metaplastic squamous cell carcinoma (MSCC) are rare types of breast cancer with specific histological features. They are characterized by rapid progression, a tendency toward cyst formation, and negativity for hormone receptors. Many studies have concluded that SCC of the breast carries a poor prognosis, based on the fact that conventional chemotherapy for ductal carcinoma of the breast is ineffective against SCC. This is a retrospective study of patients in a single center with SCC or MSCC. We searched the records of the Tokyo Metropolitan Komagome Hospital for patients diagnosed with breast SCC or MSCC between 1979 and 2006. Squamous cell carcinoma was diagnosed when 100% of the malignant cells showed a squamous component (pure SCC) and MSCC was diagnosed when more than 50% of the malignant cells showed a squamous component. We analyzed the clinicopathological features, treatment methods, and outcomes of these patients. We identified 10 (0.28%) patients with SCC or MSCC from among 3565 patients with malignant breast tumors treated at our hospital during this period. Nine patients had adenocarcinoma with squamous metaplasia, and one had pure SCC. Ultrasound showed a central cystic-necrotic component in seven tumors, and all of the tumors were negative for hormone receptors and HER2. Recurrence developed in two patients with lymph node metastasis, but not in the other eight patients. The 5-year survival rate and median survival time were 85.7% and 97 months, respectively. Squamous cell carcinoma or MSCC of the breast with features of the triple-negative subtype seems to be associated with a poor prognosis; however, nodenegative patients are likely to have a favorable prognosis.

Metaplastic Squamous Carcinoma of the Breast: Clinicopathologic Analysis of 17 Cases

Squamous cell carcinoma of the breast is very rare and it is considered to arisefrom metaplastic change of ductal carcinoma. Metaplastic squamous cell carcinoma (MSC) ofthe breast includes pure squamous cell carcinoma, metaplastic adenosquamous carcinomaand low grade adenosquamous carcinoma. Most of the cases of MSC of the breast were report-ed to have lymph node metastasis and this has a worse prognosis than that of conventionalinvasive ductal carcinoma.

Case report: Myocardial metastasis of a maxillary malignant ameloblastoma

J Oral Maxillofac Surg 61:731-734, 2003