Use of Tumor-Infiltrating Lymphocyte (TIL) Cell Therapy For Spindle Cell Carcinoma of the Breast: A Case Report.

BACKGROUND: Spindle cell carcinoma (SCC) of the breast is a rare type of metaplastic carcinoma with poor prognosis, high recurrence, and distant metastasis. Mammectomy, chemotherapy, radiotherapy, and endocrine therapy are the preferred choices of treatments. Tumor-infiltrating lymphocyte (TIL) therapy, which utilizes the patient's immune cells from the solid tumor micro-environment to eradicate cancer cells, has shown promising results in treating advanced solid tumors. However, its use for SCC of the breast has not been reported. CASE PRESENTATION: Here, we present a case of combining TIL therapy with personalized chemotherapy and endocrine therapy for the treatment of SCC of the breast. A 36-year-old Chinese woman presented with a palpable nodule (32 mm) on her left breast. Based on histological and immunohistochemical analysis of breast biopsy and surgical specimens, she was diagnosed with SCC of the breast (stage IIA). The patient received concurrent personalized chemotherapy, TIL therapy, and endocrine therapy following mammectomy. She showed no severe side effects during therapy, and did not present local recurrence or distant metastasis after follow-up for at least 14 months. CONCLUSION: To our knowledge, this is the first case report, which demonstrated that TIL therapy combined with chemotherapy/endocrine therapy after mastectomy is safe and effective for SCC of the breast.

Nonneoplastic and neoplastic sclerosing lesions of the breast.

Sclerosing lesions of the breast encompass a spectrum of benign and malignant entities and often pose a diagnostic challenge. Awareness of key morphologic features and pitfalls in the assessment of morphology and immunophenotype is essential to avoid over- or underdiagnosis and ensure optimal clinical management. This review summarizes nonneoplastic sclerosing lesions such as radial scar/complex sclerosing lesion, sclerosing adenosis, sclerosing intraductal papilloma, sclerosing variants of ductal adenoma and nipple adenoma, and fibroadenoma with extensive sclerosis, including their clinical presentation, characteristic morphology, differential diagnostic considerations, appropriate immunohistochemical work-up, when needed, and the clinical significance. In addition, atypical or neoplastic entities (such as atypical ductal hyperplasia, ductal carcinoma in situ, low-grade adenosquamous carcinoma, and fibromatosis-like metaplastic carcinoma) that can involve these sclerosing lesions are also briefly discussed.

A Rare Cutaneous Malignancy: A Primary Cutaneous Carcinosarcoma with Adnexal Epithelial Component (Trichoblastic Carcinosarcoma) of Left Temporal Region.

Primary cutaneous carcinosarcoma (PCCS) is a rare cutaneous biphasic tumour with just 120 cases being reported till date. The epithelial component trichoblastic carcinoma/ malignant trichoblastoma (trichoblastic carcinosarcoma) is even rarer, so is the present case. An eighty years old male patient presented with a rapidly progressing ulceroproliferative nodular growth on the left temporal region. The incisional biopsy showed primary cutaneous carcinomasarcoma (PCCS). IHC showed epithelial and stromal component marked exclusively for pancytokeratin (AE1/AE3) CK5&6/ p40 and vimentin respectively. Both components were immunopositive for D2-40 and immunonegative for BerEP4/ S100/ Melan A/ MITF, thus final diagnosis given was Trichoblastic carcinosarcoma. Wide excision of the lesion with local rotation flap and skin grafting (thigh skin) was done. Patient remains disease free after four years also. Present case thus highlights the importance of HPE, IHC and early surgery for excellent prognosis of PCCS.

Cáncer de mama metaplásico: a propósito de un caso / Metaplastic breast cancer: A case report

Introducción: El carcinoma metaplásico de mama (CMM) es un tipo raro y agresivo de cáncer de mama que suele diagnosticarse en etapas avanzadas, con tumores de gran tamaño y grado histológico elevado. En este estudio, presentamos un caso de CMM, y realizamos una revisión y discusión de la literatura relacionada. Principales síntomas o hallazgos clínicos: Paciente de 35 años, sin antecedentes personales ni familiares relevantes, que consulta por tumoración mamaria de 2cm, de crecimiento progresivo, que agrega en la evolución umbilicación del pezón y dolor mamario. Se realiza ecografía mamaria que evidencia masa sólida polilobulada con características sospechosas. En suma: masa en mama izquierda BI-RADS 5. Diagnósticos principales, intervenciones terapéuticas y resultados: Se realiza core biopsia y la anatomía patológica evidencia un carcinoma ductal infiltrante, variedad metaplásico, triple negativo y con expresión PDL1>1%. Se realiza mastectomía radical modificada. En la evolución se diagnostica un secundarismo pulmonar, y la paciente recibió tratamiento sistémico de primera y segunda línea. Conclusiones: Dada la naturaleza agresiva de este tipo de tumor, y las limitadas opciones de tratamiento disponibles, la participación en ensayos clínicos puede considerarse para mejorar los resultados en estas pacientes. Un enfoque multidisciplinario, y la revisión en un comité de tumores son fundamentales para guiar las decisiones terapéuticas y proporcionar la mejor atención posible a estas pacientes(AU)

Introduction: Metaplastic breast carcinoma (MBC) is a rare and aggressive type of breast cancer that is often diagnosed in advanced stages, with large tumors and a high histological grade. In this study, we present a case of MBC, and conduct a review and discussion of the related literature. Main symptoms or clinical findings: A 35-year-old patient with no relevant personal or family history presents with a progressively growing 2 cm breast mass, which, over time, develops into nipple retraction and breast pain. A breast ultrasound reveals a suspicious-looking polilobulated solid mass. In summary: a BI-RADS 5 mass in the left breast. Main diagnoses, therapeutic interventions, and outcomes: A core biopsy is performed, and the pathology report reveals an infiltrating ductal carcinoma, metaplastic variety, triple-negative with PDL1 expression > 1%. A modified radical mastectomy is performed. During follow-up, pulmonary metastasis is diagnosed, and the patient receives first and second-line systemic treatment. Conclusions: Given the aggressive nature of this type of tumor and the limited treatment options available, participation in clinical trials may be considered to improve outcomes in these patients. A multidisciplinary approach, and review in a tumor committee are essential to guide therapeutic decisions and provide the best possible care for these patients.(AU)

Malignant phyllodes tumour with lymph node metastasis: a diagnostic conundrum resolved by next generation DNA sequencing.

A malignant neoplasm with spindle cell and chondroid differentiation in the breast, metastatic to lymph node. In this context, a metaplastic carcinoma is typically favored given the exceptional nature of lymph node metastases in malignant phyllodes tumors (MPT). However, we demonstrate pathognomonic hotspot mutations in MED12 and the promoter of the TERT gene by targeted next-generation DNA sequencing, supporting a diagnosis of MPT.

Metaplastic breast carcinoma: Analysis of clinical and pathologic features, a five-year study.

Background: Metaplastic carcinoma breast (MCB) is a rare tumor comprising of both glandular and non-glandular patterns with epithelial and or mesenchymal components. Due to their varied clinicomorphological features, diagnosis has been challenging. Aim: To study the clinicopathological and histomorphology of cases of metaplastic carcinoma breast diagnosed in a tertiary care hospital along with literature review. Materials and Methods: This is a retrospective study including data of 11 patients who were diagnosed with MCB either on trucut or mastectomy specimens conducted between January 2014 and December 2018. Results: The study includes 11 patients, out of which 10 were diagnosed on mastectomy while one on trucut specimen. All the patients were women with the mean age of presentation being 43.8 years. The most common presentation was palpable breast lump with mean tumor size of 7.3 cm in greatest dimension. Skin involvement was seen in 36.3% of cases. While eight cases (72.7%) were classified as epithelial, three (27.2%) were classified as mixed. Amongst epithelial variety, in eight cases, squamous component was seen along with infiltrating ductal carcinoma (IDC) while one was pure squamous type. In mixed variety, one case showed spindled areas along with squamous areas and areas of IDC. Other two showed focal sarcomatous and cartilaginous areas in one and angiosarcomatous, bone and cartilage formation admixed with areas of IDC in other case. Conclusion: MCB are rare breast tumors with aggressive course and are characterized by their large size and rapid growth rate. Recently, there has been an upsurge in the cases of MCB due to increase in recognition of this entity. It has to be distinguished from other tumors by the pathologists so as to guide proper treatment.

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

PURPOSE: Low-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. METHODS: We 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. RESULTS: Unlike 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. CONCLUSION: Not 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.

Fibromatosis-like metaplastic carcinoma of the breast: Two case reports.

BACKGROUND: Fibromatosis-like metaplastic carcinoma is classified as a rare type of metaplastic carcinoma of the breast by the 2012 WHO pathological and genetic classification criteria for breast tumors, which takes hyperplastic spindle cells as the main component and is often misdiagnosed as benign stromal proliferative lesions or benign mesenchymal tumors of the breast because of its mild morphology. Here, we collected the clinical data of 2 cases of fibromatosis-like metaplastic carcinoma of the breast and performed pathomorphological observation and immunohistochemical staining of the surgically resected specimens. According to the clinical features, imaging features, immunophenotype, diagnosis and differential diagnosis of 2 cases of fibromatosis-like metaplastic carcinoma of the breast, it was further differentiated. CASE SUMMARY: Case 1: A 56-year-old postmenopausal female was admitted due to "right breast mass for over 1 year and local ulceration for over 1 mo". Physical examination showed a mass with a diameter of 4.5 cm × 5.5 cm palpable at 2.5 cm from the nipple at 1 o'clock in the right breast. The skin on the surface of the mass ruptured about 3 cm, with a small amount of exudation and bleeding, less clear boundary, hard texture, fair activity, without obvious tenderness. No obvious abnormality was palpable in the left breast. No enlarged lymph nodes were palpable in the bilateral axillae and bilateral supraclavicular region. After removing the mass tissue, it was promptly sent to the pathology department for examination. Case 2: Female, 52-years-old, premenopausal, admitted due to "right breast mass for more than 3 mo". Physical examination showed a 4.0 cm × 4.0 cm diameter mass palpable at 2.0 cm of the nipple in the lower outer 7 o'clock direction of the right breast, with less clear boundary, hard texture, fair activity, no significant tenderness, no palpable significant abnormalities in the left breast, and no palpable enlarged lymph nodes in the bilateral axillae and bilateral supraclavicular region. The mass was resected and sent for pathological examination. Postoperative pathological examination revealed fibromatosis-like metaplastic carcinoma of the breast in both patient 1 and patient 2. No systemic therapy and local radiotherapy were performed after surgery, and no tumor recurrence or metastasis was observed. CONCLUSION: Fibromatosis-like metaplastic carcinoma of the breast is a rare subtype of metaplastic carcinoma that is often misdiagnosed, and the diagnosis relies on medical history collection, complete sampling, and full use of immunohistochemical assessment. The risk of lymph node and distant metastasis is low, and the current treatment is based on complete surgical resection. The efficacy of systemic radiotherapy and chemotherapy is not clear.

Low-grade adenosquamous carcinoma of the breast: A rare case presentation.

Low-grade adenosquamous carcinoma of the breast is a rare variant of metaplastic mammary carcinoma. It shows indolent behavior contrary to the usual aggressive nature of metaplastic carcinomas and has a good prognosis despite being triple negative. Recurrence rates tend to be high and a consequence of incomplete excision. Although this variant has an infiltrative growth pattern, owing to its bland cytologic features, it is liable to be confused with benign sclerosing adenotic breast lesions. We present here a case of a 55-year-old postmenopausal female, who presented with a painless, mobile, hard, and nontender lump in the lower outer quadrant of the left breast, with normal overlying skin and nipple-areola complex. No associated axillary lymphadenopathy was seen. On mammography, a high-density mass of architectural distortion, characterized as BIRADS category 4C, was found. Core-needle biopsy showed haphazard glands lined by a double layer of epithelium and nests of squamoid cells arranged in an infiltrative fashion within a fibromyxoid stroma. On immunohistochemistry, tumor cells showed a lack of expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 receptor and were positive for CK 5/6 and CK7. There was counterintuitive, but characteristic positivity for myoepithelial markers calponin and CD 10 around the neoplastic nests and stromal cells expressed smooth muscle myosin. Subsequently, the patient underwent a wide local excision with free margins and sentinel lymph nodes were negative for tumor deposits. This patient remains well and free of recurrence well into follow-up.

Case Report: Gastric cancer with chondromyxoid matrix similar matrix-producing metaplastic breast carcinoma: report of an undescribed entity.

Gastric cancer is a malignant epithelial neoplasm of the stomach, including adenocarcinoma, squamous cell carcinoma, adenosquamous carcinoma, undifferentiated carcinoma, gastroblastoma and neuroendocrine neoplasms, without gastric metaplastic carcinoma. We describe a 69-year-old male patient with gastric cancer who presented with a novel, biphasic histologic morphology with one component consisting of poorly differentiated adenocarcinoma and the other component consisting of chondromyxoid matrix with adenocarcinoma transition to, between the two components without a spindle cell component. The histological morphology of this case is similar to matrix-producing metaplastic breast carcinoma. Therefore, we diagnose this case as gastric carcinoma with chondromyxoid matrix similar matrix-producing metaplastic breast carcinoma.

Pleomorphic Adenoma of the Breast: A Rare Benign Lesion Masquerading as a Metaplastic Breast Carcinoma on Core-Needle Biopsy.

We report a rare case of pleomorphic adenoma (benign mixed tumor) of the breast in a 66-year-old female. A 5.5 cm hypoechoic mass with lobulated margins was noted on ultrasound. A biopsy showed an atypical cartilaginous lesion, leading to a subsequent segmental mastectomy, which was initially interpreted as metaplastic breast carcinoma. On the second review at our tertiary care center, a diagnosis of a pleomorphic adenoma was favored due to the circumscription and the benign epithelial component. Due to unfamiliarity with this entity, this neoplasm has occasionally been misdiagnosed clinically and even been overcalled on core needle biopsies. Careful clinical, radiological, and pathological correlation is required to avoid unnecessarily aggressive surgery, and a differential diagnosis of pleomorphic adenoma must be included in cases of well-demarcated breast masses showing myxoid or cartilaginous changes on core-needle biopsy.

Metaplastic Breast Carcinoma Revisited; Subtypes Determine Outcomes: Comprehensive Pathologic, Clinical, and Molecular Review.

Metaplastic breast carcinoma (MpBC) is a heterogeneous group of tumors that clinically could be divided into low risk and high risk. It is important to recognize the different types of MpBC, as the high-risk subtypes have worse clinical outcomes than triple-negative breast cancer. It is important for the pathologist to be aware of the MpBC entities and use the proposed algorithms (morphology and immunohistochemistry) to assist in rendering the final diagnosis. Few pitfalls are discussed, including misinterpretation of immunohistochemistry and certain histomorphologies, particularly spindle lesions associated with complex sclerosing lesions.

Metaplastic Carcinoma of the Breast: Case Series of a Single Institute and Review of the Literature.

Metaplastic carcinoma of the breast (MpBC) is a very rare and aggressive type of breast cancer. Data focusing on MpBC are limited. The aim of this study was to describe the clinicopathological features of MpBC and evaluate the prognosis of patients with MpBC. Eligible articles about MpBC were identified by searching CASES SERIES gov and the MEDLINE bibliographic database for the period of 1 January 2010 to 1 June 2021 with the keywords metaplastic breast cancer, mammary gland cancer, neoplasm, tumor, and metaplastic carcinoma. In this study, we also report 46 cases of MpBC stemming from our hospital. Survival rates, clinical behavior, and pathological characteristics were analyzed. Data from 205 patients were included for analysis. The mean age at diagnosis was 55 (14.7) years. The TNM stage at diagnosis was mostly stage II (58.5%) and most tumors were triple negative. The median overall survival was 66 (12-118) months, and the median disease-free survival was 56.8 (11-102) months. Multivariate Cox regression analysis revealed that surgical treatment was associated with decreased risk of death (hazard ratio 0.11, 95% confidence interval 0.02-0.54, p = 0.01) while advanced TNM stage was associated with increased risk of death (hazard ratio 1.5, 95% confidence interval 1.04-2.28, p = 0.03). Our results revealed that surgical treatment and TNM stage were the only independent risk factors related to patients' overall survival.

Low-grade adenosquamous carcinoma of the breast: a clinical, morphological and immunohistochemical analysis of 25 patients.

AIMS: Due to its rarity and non-specific clinical and pathological features, low-grade adenosquamous carcinoma (LGASC) of the breast continues to pose diagnostic challenges. Unlike other triple-negative breast carcinomas, LGASC tends to have an indolent clinical behaviour. It is essential to recognise this lesion for accurate diagnosis and appropriate management. METHODS AND RESULTS: Twenty-five cases of LGASC were identified in our archives and collaborating institutes. Cases of LGASC with dominant coexisting other type carcinomas were excluded. We studied the clinical presentation, morphological features, patterns of the commonly used immunohistochemical stains and follow-up. In our cohort, LGASC was commonly located at the outer aspect of the breast and associated with intraductal papilloma. The morphology of LGASC is characterised by infiltrating small glands and nests with variable squamous differentiation. We also found cuffing desmoplastic (fibrolamellar) stromal change in 75% of patients and peripheral lymphocytic aggregates in 87.5% of patients. P63 and smooth muscle myosin (SMM) were the most common myoepithelial markers used to assist in diagnosis. P63 often stained peripheral tumour cells surrounding invasive glands (circumferential staining in 80% of the cases), mimicking myoepithelial cells. It also stained the small nests with squamous differentiation. However, SMM was negative in 63% of the cases. The vast majority of our cases were triple-negative; only a few had focal and weak expressions of ER and PR. One patient who did not have excision developed lymph node metastasis. Most patients underwent excision or mastectomy with negative margins as surgical treatment; there were no recurrences or metastases in these patients with clinical follow-ups up to 108 months. CONCLUSIONS: LGASC has some unique, although not entirely specific, morphological features and immunohistochemical staining patterns. Fibrolamellar stromal change, peripheral lymphocytic aggregates and variable staining of p63 and SMM are valuable features to facilitate the diagnosis.

Metaplastic carcinoma of the breast: matched cohort analysis of recurrence and survival.

PURPOSE: Metaplastic breast carcinoma (MBC) is a rare subtype of breast cancer, defined as mammary carcinoma with squamous or mesenchymal differentiation, that may include spindle cell, chondroid, osseous, or rhabdomyoid differentiation patterns. The implications of MBC recurrence and survival outcomes remains unclear. METHODS: Cases were ascertained from a prospectively maintained institutional database of patients treated from 1998 to 2015. Patients with MBC were matched 1:1 to non-MBC cases. Cox proportional-hazards models and Kaplan-Meier estimates were used to evaluate outcome differences between cohorts. RESULTS: 111 patients with MBC were matched 1:1 with non-MBC patients from an initial set of 2400 patients. Median follow-up time was 8 years. Most patients with MBC received chemotherapy (88%) and radiotherapy (71%). On univariate competing risk regression, MBC was not associated with locoregional recurrence (HR = 1.08; p = 0.8), distant recurrence (HR = 1.65; p = 0.092); disease-free survival (HR = 1.52; p = 0.065), or overall survival (HR = 1.56; p = 0.1). Absolute differences were noted in 8-year disease-free survival (49.6% MBC vs 66.4% non-MBC) and overall survival (61.3% MBC vs 74.4% non-MBC), though neither of these reached statistical significance (p = 0.07 and 0.11, respectively). CONCLUSION: Appropriately-treated MBC may exhibit recurrence and survival outcomes that are difficult to distinguish from those of non-MBC. While prior studies suggest that MBC has a worse natural history than non-MBC triple-negative breast cancer, prudent use of chemotherapy and radiotherapy may narrow these differences, although studies with more power will be required to inform clinical management. Longer follow-up among larger populations may further elucidate the clinical and therapeutic implications of MBC.

Basal cell carcinosarcoma: a systematic review and reappraisal of its challenges and the role of Mohs surgery.

Basal cell carcinosarcoma (BCCS) is a rare malignant biphasic tumor of the skin, composed of epithelial and mesenchymal components, and may be underdiagnosed. We sought to summarize the current understanding of BCCS including its reported history, clinical presentation, diagnosis, and treatment. We also reappraise and present our recommendations of histological interpretation for its diagnosis and treatment. A systematic review of PubMed and EMBASE, from inception of databases to December 1, 2022, identified all reported cases of basal cell carcinosarcoma. A total of 34 reports containing 54 patients with basal cell carcinosarcoma were included. The neoplasm was most commonly associated in areas of sun-exposed skin and primarily affected the elderly. Diagnosis was made on histology specimens using H&E. To address underdiagnosis, additional immunohistochemical markers have been proposed due to unreliable phenotypic appearance in this poorly differentiated neoplasm. Treatment consists of excision of the tumor, typically with Mohs surgery, and is curative in most cases. There are limited treatment options for metastatic disease. There were limitations to this study as various immunohistochemical stains used on suspected BCCS without providing an explanation as to why certain markers were included and others were excluded. Continued efforts in characterizing this complex neoplasm are critical in establishing reliable and accurate diagnostic tests and accompanying treatment options, especially in cases of metastatic disease.

A molecular reappraisal of matrix-producing breast metaplastic carcinoma highlighted by PLAG1 and MYC rearrangements.

BACKGROUND: Very little is currently known about molecular alteration of matrix-producing carcinoma of the breast. However, the morphological similarity with other neoplasm with a myxo-chondroid component is remarkable. In this pilot study we evaluated the molecular alterations involving PLAG1 and MYC genes in 12 cases of matrix producing carcinoma. METHODS: We evaluated PLAG1 rearrangements as Break-Apart and Gene Copy Gain, and MYC as amplification and polysomy in 12 cases of matrix producing carcinoma using a FISH method. RESULTS: Among the 12 cases of matrix producing carcinomas we found that the three cases harboring MYC amplification were all negative for PLAG1 break-apart; four cases with MYC polysomy were associated to PLAG1 break-apart and high Gene Copy Number; among four cases wild type for MYC, three showed a PLAG1- break-apart signal and of them two died with disease. One of the deceased patients showed an amplification of MYC with PLAG1- wild-type and the other showed a PLAG1 break-apart (6%) and a MYC wild-type. CONCLUSION: This is the first report to the best of our knowledge that shows a possible correlation between a matrix producing carcinoma with PLAG1 and MYC involvement in the development and progression of this kind of tumor. We can suppose that MYC amplification behaves in an aggressive way together with PLAG1- break-apart in the cases of matrix producing carcinoma presented here. The gene copy gain is a useful diagnostic tool in the case of difficult diagnosis because an increase was observed in more than 50% of cases.

Metaplastic Carcinoma of the Breast: MRI Features with Clinical and Histopathologic Correlation.

RATIONALE AND OBJECTIVES: Metaplastic carcinoma of the breast (MCB) is a rare type of breast carcinoma, and there are only limited data about the MRI findings of MCB. This article aimed to review the MRI features of MCB and correlate the MRI findings with clinical and histopathologic characteristics. MATERIALS AND METHODS: A total of 23 patients were enrolled from a signal institution. The clinical data, histological diagnosis and MRI findings were retrospectively reviewed. RESULTS: The average age of the 23 patients was 51.6 years. Twenty-one (91.3%) patients presented with a palpable mass. Squamous cell carcinoma was the most common subtype (10/23, 43.5%). Axillary lymph node metastasis was detected in 4 (17.4%) patients. The immunohistochemical profile showed the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor-2 (Her-2) expression were negative in 87.0%, 95.7%, and 91.3% of the patients respectively. On MRI, most cases exhibited an irregular mass (18/23, 78.3%) with high signal intensity on T2-weighted images (22/23,95.7%), non-circumscribed margin (19/23, 82.6%), heterogeneous enhancement (13/23, 56.5%), Type III (12/23, 52.2%) time intensity curve, and diffusion restriction (20/23, 87.0%) on diffusion weighted images (DWI). CONCLUSION: MCB most commonly demonstrated definitely malignant MRI features, which may reflect the histopathologic characteristic of this rare and aggressive breast carcinoma.

Revisiting Metaplastic Carcinoma of Breast: An Emphasis on the Clinico-pathological and Immunohistochemical Variables Analyzed at a Tertiary Cancer Centre in South India.

Background & Objective: Metaplastic carcinoma is a diverse variant of invasive breast carcinomas (IBC) characterized by dedifferentiation of malignant cells towards squamous and/or mesenchymal elements. It accounts for 0.3-1.2% of all IBC. These tumors are typically triple-negative by hormonal profiling with a high proliferation index and a dismal prognosis. Lymph node metastasis is an unusual feature in metaplastic carcinoma. Methods: The present study analyses 30 cases (26 cases of modified radical mastectomy and 4 cases of lumpectomy) of metaplastic carcinoma over 2018-2020 (3 years). Four oncopathologists reviewed routine histopathologic and immunohistochemical-stained slides. The clinical details were collected from the Medical Records Department of the Cancer Institute. Results: A total of 20 (66.67%) cases were patients >50 years of age, 21(70%) out of which were diagnosed as invasive carcinoma, grade 3 according to the Nottingham histological score. Five (16.7%) cases presented with lymph node metastasis. While immunohistochemically 28 (93.3%) cases were triple-negativeCK5/6, P63, EGFR, and Ki-67 (more than 40%) positivity was noted in 25 (83.3%) , 26 (86,7%) , 20 (66.7%), and 25 (83.3%) cases, respectively. Conclusion: Metaplastic carcinoma is characteristically triple-negative breast malignancies (TNBC) exhibiting a high Ki-67 index and a lower rate of lymph node metastasis. CK5/6, p63, and EGFR are pertinent immunohistochemical markers that may aid in diagnosis. However, those markers are non-specific for the disease and morphologic features are always the key to diagnosis of the process.