Primary combined malignant melanoma and ductal carcinoma of the breast: A report of two cases

The "Forgotten" Subtypes of Breast Carcinoma: A Systematic Review of Selected Histological Variants Not Included or Not Recognized as Distinct Entities in the Current World Health Organization Classification of Breast Tumors

Breast carcinoma is the most common cancer in women. Nineteen different subtypes of breast carcinomas are recognized in the current WHO classification of breast tumors. Except for these subtypes, there are a number of carcinomas with special morphologic and immunohistochemical features that are not included in the 5th WHO classification, while others are considered special morphologic patterns of invasive breast carcinoma of no special type. In this manuscript, we systematically review the literature on four different subtypes of invasive breast carcinoma, namely lymphoepithelioma-like breast carcinoma, breast carcinoma with osteoclast-like giant cells, signet-ring breast carcinoma, and metaplastic breast carcinoma with melanocytic differentiation. We describe their clinicopathological characteristics, focusing on the differential diagnosis, treatment, and prognosis.

Primary melanoma of the nipple: Report of 10 cases including coexistence with Paget's disease

Primary melanoma of the nipple (PMN) is exceedingly rare, with only single cases reported to date. We identified 10 patients with PMN: 5 females, 5 males, median age 55.5 years (range 29-66) at diagnosis of melanoma in situ (4 cases) or invasive melanoma (6 cases, Breslow depth 0.2 mm to 3.5 mm). Follow-up was available for all 10 patients (median 19 months, range 1-183). Nine patients had no evidence of disease; one patient died of disease (13.5 months) after presenting with a nodal metastasis. One case was exceptional, because the patient presented with a pigmented lesion that histopathologically exhibited co-existence of melanoma in situ and Paget disease, a challenging differential diagnosis due to immunohistochemical pitfalls in distinction between melanoma in situ and the pigmented variant of mammary Paget disease. Here we report the second largest series of PMN including a case of PMN colliding with mammary Paget disease, to raise awareness of these rare malignancies.

Clinical characteristics and survival of second primary breast carcinoma with extramammary malignancies

Objectives

To investigate the characteristics, diagnosis, survival and prognosis of second primary breast carcinoma (SPBC).

Materials and methods

Records of 123 patients with SPBC in Tianjin Medical University Cancer Institute & Hospital between December 2002 and December 2020 were retrospectively reviewed. Clinical characteristics, imaging features and survival were analyzed and comparisons between SPBC and breast metastases (BM) were made.

Results

Of 67156 newly diagnosed breast cancer patients, 123 patients (0.18%) suffered previous extramammary primary malignancies. Of the 123 patients with SPBC, approximately 98.37%(121/123)were female. The median age was 55 years old (27-87). The average diameter of breast mass was 2.7 cm (0.5-10.7). Approximately 77.24% (95/123) of the patients presented with symptoms. The most common types of extramammary primary malignancies were thyroid, gynecological cancers, lung, and colorectal. Patients with the first primary malignant tumor of lung cancer were more likely to develop synchronous SPBC, and those with the first primary malignant tumor of ovarian cancer were more likely to develop metachronous SPBC. When comparing with BM, patients with SPBC were more often older (≥45 years old), at earlier stages (I/II), more microcalcification and less multiple breast masses in imaging. More than half (55.88%) of patients in the metachronous group developed primary breast cancer within 5 years after diagnosis of extramammary primary cancer. The median overall survival time was 71 months. Within 90 months, the prognosis of patients with synchronous SPBC was worse than that of patients with metachronous SPBC (p=0.014). Patients with BM had the worst outcome compared with patients with synchronous SPBC and metachronous SPBC (p<0.001).ER/PR-negative status, an interval of less than 6 months between the onset of two tumors, a late stage of first primary malignancy, and an age of diagnosis of first primary malignancy greater than 60 years predicted a worse prognosis for patients with SPBC.

Conclusion

The possibility of SPBC should be considered during the follow-up of patients with primary extramammary malignancy, especially within 5 years of the onset of the first tumor. The stage of first primary malignancy and the age at diagnosis of first primary malignancy have an impact on the prognosis of patients with SPBC.

Triple Primary Malignancies: Tumor Associations, Survival, and Clinicopathological Analysis: A 25-Year Single-Institution Experience

The detection of multiple primary malignancies is on the rise despite their rare occurrence rate. This research aims to determine the prevalence, tumor association patterns, overall survival, and the correlation between survival time and independent factors in patients with triple primary malignancies. This single-center retrospective study included 117 patients with triple primary malignancies admitted to a tertiary cancer center between 1996 and 2021. The observed prevalence was 0.082%. The majority of patients (73%) were over the age of fifty at the first tumor diagnosis, and regardless of gender, the lowest median age occurred in the metachronous group. The most common tumor associations were found between genital-skin-breast, skin-skin-skin, digestive-genital-breast, and genital-breast-lung cancer. The male gender and being over the age of fifty at the first tumor diagnosis are associated with a higher risk of mortality. Compared with the metachronous group, patients with three synchronous tumors demonstrate a risk of mortality 6.5 times higher, whereas patients with one metachronous and two synchronous tumors demonstrate a risk of mortality three times higher. The likelihood of subsequent malignancies should always be considered throughout cancer patients' short- and long-term surveillance to ensure prompt tumor diagnosis and treatment.

Mammary Paget Disease With Melanocytic Proliferation Mimicking Malignant Melanoma in situ: A Case Report

Several cases of pigmented mammary Paget’s disease (PMPD) mimicking cutaneous malignant melanoma have been reported. In these cases, the tumor cells are colonized by melanocytes, particularly with the presence of a population of melanocytes staining for HMB-45 and S100. Here, we report a case of mammary Paget disease (MPD) which was misdiagnosed as melanoma in situ due to the interpretation of the staining of melanocytic markers S-100, Melan-A, and HMB-45. The tumor cells strongly expressed CK7 and GATA3, and a dual-labeling showed negative PHH3 labeling for the melanocytes. Pathologists need to be aware of the caveat of colonization of melanocytes in Paget disease.

Simultaneous primary invasive breast carcinoma and ipsilateral cutaneous melanoma of the back: Surgical approach and considerations, a case report

INTRODUCTION AND IMPORTANCE

A patient presented with ipsilateral, synchronous primary malignancies of left upper back melanoma and left breast invasive ductal carcinoma. This complex presentation was managed with a multidisciplinary approach.

CASE PRESENTATION

A 61-year-old female presented with multiple cutaneous lesions, revealed to be several foci of melanoma in situ as well as a T4b melanoma of the left upper back. On staging work up, a left breast malignancy was incidentally discovered. Genetic testing did not delineate a relevant mutation to explain the synchronous malignancies. Multidisciplinary surgical planning entailed consideration of the lymphatic drainage patterns of the lesions, with both the upper back melanoma and breast carcinoma expected to drain to the left axilla. Ultimately, simultaneous resections of both malignancies were performed as well as concomitant left sentinel lymph node biopsies utilizing dual tracer technique.

CLINICAL DISCUSSION

Currently, cases of synchronous primary cutaneous melanoma and independent, ipsilateral primary breast carcinoma have not been examined, and thus surgical considerations for axillary staging in this circumstance have not been discussed. The existing literature instead explores the incidence and operative challenges of one malignancy following the other after an interval of time.

CONCLUSION

This case highlights the utility of a multidisciplinary team for complex oncologic presentations and discusses a creative surgical approach to address two simultaneous primary malignancies involving the left breast and ipsilateral skin of the back. This case emphasizes an exceedingly rare presentation and serves as an important example to educate medical professionals on the innovative and team-based approach to treatment.

Previously diagnosed multiple primary malignancies in patients with breast carcinoma in Western Sweden between 2007 and 2018

PURPOSE

Multiple primary malignancies (MPMs) caused by breast cancer treatment are well described, but only few studies to date describe which other previous primary malignancies (OPPMs) occur before breast cancer. The purpose of the present study was to evaluate the prevalence of OPPMs in patients with breast cancer between 2007 and 2018 in Western Sweden.

METHODS

Patient selection was performed using both pathology reports at Sahlgrenska University Hospital (Sweden) and the Swedish Cancer Registry. All newly diagnosed breast cancer patients were screened for presence of OPPM.

RESULTS

In total, 8031 breast cancer patients were diagnosed at Sahlgrenska University Hospital between 2007 and 2018. The prevalence of breast cancer patients with OPPMs (n = 414) increased from on average 2.6% to 8.2% during this 12-year period and ranged from 17 to 59 patients annually. The most striking increase in prevalence was found among the gynecological tumors (endometrium and ovarian adenocarcinomas), malignant melanomas and gastrointestinal malignancies. These findings were validated using data of the Swedish Cancer Registry.

CONCLUSIONS

The overall survival rates for cancer patients have improved tremendously during the past 40 years, in part due to individually tailored therapies and screening programs. Our study revealed an increasing trend of OPPMs in breast cancer patients.

Malignant melanoma of the breast: controversies in the diagnosis and therapeutic management of a rare nosologic entity

Melanoma of the breast is an infrequent entity, presenting as either primary or metastatic from extramammary solid neoplasms. Depending on the involvement of the skin, primary malignant melanoma of the breast (PMMB) can be classified as cutaneous or noncutaneous. Cutaneous PMMB accounts for <5% of all melanomas and only 0.5% of all breast cancers. Furthermore, despite the rarity of metastatic breast neoplasms, melanoma comprises a frequent source of metastases. Metastatic potential of melanoma is associated with poor prognosis, and the majority of patients present more than one metastatic foci at the time of diagnosis. Diagnostic approach for both primary and metastatic melanomas of the breast is substantiated by fine needle aspiration (FNA) cytology along with immunohistochemistry. Nevertheless, verification of a metastatic mammary melanoma requires the discovery of a primary lesion. The mainstay of treatment for primary tumors is surgery, with radical local excision and axillary lymph node dissection or, on occasion, axillary sentinel node resection, while for metastatic tumors it depends on the specificities of the melanoma. Adjuvant therapy is always implemented. The aim of this survey is to meticulously review the literature of primary and metastatic malignant melanomas of the breast and report epidemiologic and clinicopathologic data for this rare entity. Clinical features, histogenesis, morphological, and immunochemical findings are discussed, while the role of current diagnostic and therapeutic management of this uncommon entity is emphasized.

Tyrosinase mRNA RT-PCR Analysis as an Additional Diagnostic Tool for the Identification of Melanoma Cells in Biological Fluid Samples other than Blood: A Preliminary Report

Reverse transcription polymerase chain reaction (RT-PCR) of tyrosinase mRNA has been applied for the detection of melanoma cells in the peripheral blood, lymph nodes and bone marrow of melanoma patients. We evaluated the diagnostic accuracy of RT-PCR in comparison to standard cytology and immunocytochemistry (ICC) for the identification of melanoma cells in biological fluids other than blood. Tyrosinase expression was evaluated together with standard cytology and ICC (anti-S100, HMB-45 and Melan-A antibodies) in biological fluid samples collected from 17 melanoma patients according to the site of metastatic involvement or clinical suspicion (eight cerebrospinal fluid (CSF) samples; three pleural effusions; four ascites; one bile sample, one pericardial effusion); 17 samples collected from patients with non-melanoma metastatic cancer were used as controls. Tyrosinase expression in the biological fluid sample was compared with the expression determined at the same time in peripheral blood. Positive tyrosinase expression was found in 12/17 melanoma and 3/17 non-melanoma cancer patients. Cytology/ICC showed the presence of neoplastic cells in only 7/12 melanoma samples with positive tyrosinase expression: radiological evidence of disease involvement was found in all these patients (three meningeal, two pleural, two peritoneal). Clear-cut radiological evidence of disease involvement at the sampling site was found in the five patients with negative cytology/ICC and positive RT-PCR (one CSF; four serous membrane effusions); all patients died of disease progression within four months of sampling. The five patients who were negative for both cytology/ICC and RT-PCR did not show any clinical evidence of disease recurrence at the sampling site. Only five of the 12 metastatic patients with positive tyrosinase expression in biological fluid showed positivity for tyrosinase in the peripheral blood. These preliminary results suggest that the analysis of biological fluids other than blood could be considered as a new potential clinical field of application for the tyrosinase mRNA assay.

Merkel cell carcinoma, melanoma, metastatic mimics of breast cancer

Merkel cell carcinoma and melanoma can each occur primarily in breast skin, or metastasize to the breast. The breast is a rare site of metastasis of essentially any and every type of tumor, including carcinomas, sarcomas, and hematolymphoid neoplasms, and 10-30% of breast metastases may represent the initial presentation of disease. Although metastases generally recapitulate histologic features of the primary tumor, they are diagnostically challenging given their rarity and morphologic overlap with breast carcinoma, including special types of breast cancer. Histologic clues may include lack of carcinoma in situ, lack of central elastosis, pattern of infiltration around normal breast structures, yet none of these are specific. Careful correlation with clinical history and judicious use of immunostain panels is essential in approaching these cases.

Combined cutaneous tumors with a melanoma component: A clinical, histologic, and molecular study

BACKGROUND

The histogenesis and clinical behavior of combined cutaneous tumors (CCTs) in which the mesenchymal component consists of melanoma remain unclear.

OBJECTIVE

We sought to characterize the clinical, histologic, and molecular findings in CCTs with an epithelial and a melanoma component.

METHODS

We retrospectively reviewed the records from 2 institutions for CCTs. Fluorescence in situ hybridization was performed to assess chromosomal copy number alterations in both components.

RESULTS

Sixteen CCTs were included. The most common subtype was the squamomelanocytic tumor (11), followed by the basomelanocytic tumor (3) and the trichoblastomelanoma (2). CCTs were more common in men (87%), on the head and neck (57%), and had extensive solar elastosis (81%). The median follow-up was 25 months (range, 8-167 months). One case had an adverse outcome. Fluorescence in situ hybridization revealed chromosomal alterations in approximately 55% of the cases. Five cases showed chromosomal gains only in the melanocytic component. One case showed 11q13 gains in both the epithelial and melanocytic components.

LIMITATIONS

Our study is retrospective and the sample is small.

CONCLUSIONS

The low incidence of adverse outcomes suggests that CCT may be more indolent than noncombined tumors. 11q13 amplification in both components supports the theory of dual differentiation from a common progenitor cell.

Phyllodes Tumor of the Breast With Malignant Melanoma Component

Phyllodes tumors of the breast display a wide variation in histological appearance and are classified into benign, borderline, and malignant categories based on a combination of histological parameters. These tumors may include a malignant heterologous component that is believed to originate through a process of multidirectional differentiation from a cancer stem cell. In these cases, the tumor is classified as a malignant phyllodes tumor. Among the heterologous elements that have been described in malignant phyllodes tumors are rhabdomyosarcoma, chondrosarcoma, osteosarcoma, liposarcoma and angiosarcoma. We present the first case of a phyllodes tumor with a malignant melanoma component in the breast of a 71-year-old lady, discussing the clinical implications of this diagnosis.

[Mixed breast carcinoma with melanocytic differentiation in a man]

INTRODUCTION

Male breast cancer is rare; the lobular type is exceptional. Only one case of mixed ductal and lobular type is reported in the literature. This is the first report on a mixed ductal and lobular carcinoma with melanocytic differentiation in a man. The aim of our study is to describe the clinicopathological characteristics of this rare type of breast tumor and to discuss its histogenesis.

CASE REPORT

A 63-year-old man presented with cutaneous ulceration of the left breast. Ultrasound of the breast revealed a solid hypoechoic lesion, 13 mm in diameter. Microscopic evaluation of the biopsy showed an invasive ductal carcinoma. The patient received three cycles of chemotherapy and lost of view. Then consulted for increasing of the tumor size reaching 3 cm. Histological examination of the mastectomy specimen showed a mixed ductal and lobular carcinoma with melanocytic differentiation, confirmed by the immunohistochemical study. The patient received adjuvant chemotherapy and the evolution was favorable with an average follow-up of 9 months.

CONCLUSION

Breast carcinoma with melanocytic differentiation is extremely rare; only seven cases are reported in the literature and all occurs in females. Its histogenesis is unclear; tumors exhibiting this combination of cell types may occur as collision or composite tumors.

Metastases to and from the Breast

Breast cancer is a common source of systemic metastatic disease. Distinguishing metastatic breast cancer from other types of malignancies can be diagnostically challenging but is important for correct treatment and prognosis. Nonmammary tumors can also metastasize to the breast, although this is a rare phenomenon. Differentiating a metastasis to the breast from a primary breast cancer can likewise be difficult. Knowledge of the clinical history and careful morphologic evaluation are the cornerstones of diagnosis. A panel of immunohistochemical stains tailored to the differential diagnosis at hand can provide helpful information in ambiguous cases.

CD36-mediated activation of endothelial cell apoptosis by an N-terminal recombinant fragment of thrombospondin-2 inhibits breast cancer growth and metastasis in vivo

Thus far the clinical benefits seen in breast cancer patients treated with drugs targeting the vascular endothelial growth factor (VEGF) pathway are only modest. Consequently, additional antiangiogenic approaches for treatment of breast cancer need to be investigated. Thrombospondin-2 (TSP-2) has been shown to inhibit tumor growth and angiogenesis with a greater potency than the related molecule TSP-1. The systemic effects of TSP-2 on tumor metastasis and the underlying molecular mechanisms of the antiangiogenic activity of TSP-2 have remained poorly understood. We generated a recombinant fusion protein consisting of the N-terminal region of TSP-2 and the IgG-Fc1 fragment (N-TSP2-Fc) and could demonstrate that the antiangiogenic activity of N-TSP2-Fc is dependent on the CD36 receptor. We found that N-TSP2-Fc inhibited VEGF-induced tube formation of human dermal microvascular endothelial cells (HDMEC) on matrigel in vitro and that concurrent incubation of anti-CD36 antibody with N-TSP2-Fc resulted in tube formation that was comparable to untreated control. N-TSP2-Fc potently induced apoptosis of HDMEC in vitro in a CD36-dependent manner. Moreover, we could demonstrate a CD36 receptor-mediated loss of mitochondrial membrane potential and activation of caspase-3 in HDMEC in vitro. Daily intraperitoneal injections of N-TSP2-Fc resulted in a significant inhibition of the growth of human MDA-MB-435 and MDA-MB-231 tumor cells grown in the mammary gland of immunodeficient nude mice and in reduced tumor vascularization. Finally, increased serum concentrations of N-TSP2-Fc significantly inhibited regional metastasis to lymph nodes and distant metastasis to lung as shown by quantitative real-time alu PCR. These results identify N-TSP2-Fc as a potent systemic inhibitor of tumor metastasis and provide strong evidence for an important role of the CD36 receptor in mediating the antiangiogenic activity of TSP-2.

Synchronous collision malignant melanoma and adenocarcinoma of the rectum

"Collision tumors" consist of two independent but coexisting tumors. This uncommon situation might be easily mistaken for a composite tumor where one histogenetic event originates from two apparently distinct neoplasms. Colorectal collisions are particularly unusual; here, we report the exceedingly rare case of a 61-year-old man with malignant melanoma and adenocarcinoma colliding in the rectum. Collision tumors have an idiopathic pathophysiology and in fact "accidental meeting" is accepted by many authors. This article discusses the concepts about cancer development, which are overlooked by this hypothesis, another theory to explain that this rare occurrence involves microenvironment changes.

Metaplastic breast carcinoma with melanocytic differentiation

Metaplastic carcinoma of the breast is a rare heterogeneous malignancy, accounting for <1% of all invasive breast carcinomas, in which adenocarcinoma is found to coexist with an admixture of spindle, squamous, chondroid or bone-forming neoplastic cells. Metaplastic breast carcinoma composed of both epithelial and melanocytic elements is rare, and only seven cases have been reported so far. Reported herein is the case of a 38-year-old woman with a nodular mass in her left breast suspicious of malignancy, discovered during routine ultrasound examination. After histological and immunohistochemical examination of the resected tumor mass, initial diagnosis was collision tumor: ductal invasive carcinoma and metastatic melanoma. The patient underwent quadrantectomy, chemotherapy and radiotherapy. At 6 years follow up the patient was alive and healthy, without local recurrence or metastases. After revising slides and the literature, in addition to patient follow up, it was concluded that this case represents metaplastic carcinoma with melanocytic differentiation.

MDA-MB-435 and M14 cell lines: identical but not M14 melanoma?

A controversy has arisen over the past several years about the true origin of the human MDA-MB-435 cell line. Originally described as a human breast cancer cell line, subsequent expression array studies instead suggested a gene expression profile consistent with a melanoma origin. Subsequent karyotype and comparative genomic hybridization studies supported the idea that current stocks of both MDA-MB-435 cells and M14 melanoma cells must be identical cell lines, and the conclusion was drawn that both cell lines were in fact M14 melanoma cells. However, an alternate conclusion based on these data is that both cell lines are indeed identical, but are in fact MDA-MB-435 breast cancer cells. There is evidence that many cell lines can display "lineage infidelity" and that assignment to tissue type is unreliably made based on expression patterns. Evidence from the literature is presented here that is inconsistent with both lines being of M14 melanoma origin, but rather is consistent with both cell lines being of MDA-MB-435 breast cancer origin.

A Case of Pigmented Mammary Paget's Disease

Pigmented mammary Paget's disease is a uncommon clinicopathologic variant of mammary Paget's disease, and this mimics malignant melanoma both clinically and histopathologically. Herein, we report on a rare case of pigmented mammary Paget's disease. An 81-year-old woman presented with 2.5×1 cm sized, red and brown, eczematous plaque on her right areola, and she'd had this lesion for 3 years. Histopathology showed large, atypical cells with large nuclei and abundant pale cytoplasm throughout the epidermis. Dispersed melanocytes were noted in the epidermis and some of the Paget's cells contained melanin within their cytoplasm. Immunohistochemical studies demonstrated that the intraepidermal pagetoid cells were positive for cytokeratin 7; in contrast, they were negative for S-100, Periodic-acid Schiff (PAS), Alcian blue at PH 2.5, HMB-45 and carninoembryonic antigen (CEA). We recommend that pigmented mammary Paget's disease should be included in the differential diagnosis of pigmented lesions on the nipple.

Report of a metaplastic carcinoma of the breast with multi-directional differentiation: an adenoid cystic carcinoma, a spindle cell carcinoma and melanoma

Metaplastic carcinoma of the breast is a heterogeneous neoplasia, generally composed of both epithelial and mesenchymal components. We report an unusual case of mammary metaplastic carcinoma in a 51-year-old female patient. Needle core biopsy from the tumour mass showed malignant epithelial and sarcomatous features. The resection specimen revealed a multi-directional tumour differentiation consisting predominantly of: firstly, a poorly differentiated basaloid epithelial cell type, consistent with an adenoid cystic carcinoma; secondly, areas of a spindle cell carcinoma; and, thirdly, areas with a melanocytic differentiation. This is the first report on a metaplastic carcinoma of the breast presenting as an admixture of an adenoid cystic carcinoma and melanoma.

Unusual occurrence of a melanoma with intermixed epithelial component: a true melanocarcinoma?: case report and review of epithelial differentiation in melanoma by light microscopy and immunohistochemistry

We report a case of a 27-year-old woman with a nonpigmented lesion on the right scalp. Histological examination showed a malignant nodular neoplasm with 2 distinct but intimately admixed components: a malignant melanoma with a spindle component and an unusual glandular component. Immunohistochemical studies demonstrated epithelial differentiation on the basis of cytokeratin (CAM5.2 and AE1/AE3) expression in the glandular component and melanocytic differentiation (HMB-45, PNL2, MITF, and S-100) of the spindle cell component. A single melanocytic marker (MITF) was expressed in both components, raising the possibility of dual differentiation in a single tumor, rather than the alternative considerations of a collision tumor or a reactive pseudoepitheliomatous hyperplasia with eccrine duct lumen formation within a melanoma. This unusual tumor with both melanocytic and epithelial components may represent a true melanocarcinoma, which becomes a plausible consideration, in view of melanoma plasticity and recent experimental evidence and speculation about the role of stem cells in melanoma.

Breast carcinoma and malignant melanoma metastasis within a single axillary lymph node

A 58 year old lady presented with a right breast cancer and a prior history of malignant melanoma excised from the right chest wall eight years previously. An abnormal axillary lymph node resected contained features of both metastatic breast carcinoma and malignant melanoma. Following oncologic breast cancer management, the patient is well with no evidence of recurrence at three years.

Doença de Paget pigmentada do mamilo simulando melanoma cutâneo: importância da imuno-histoquímica na diferenciação dessas doenças

A variante pigmentada da doença de Paget mamária é rara, com cerca de 12 casos relatados, e pode mimetizar clínica e histologicamente o melanoma. Como na forma clássica, em geral associa-se à neoplasia da mama acometida, com origem principalmente no carcinoma intraductal que se estende à epiderme através de ducto lactóforo. A fisiopatologia da hiperpigmentação permanece desconhecida. Relata-se o caso de paciente de 49 anos que apresentou lesão pigmentada do mamilo, suspeita de melanoma. O exame histológico não foi suficiente para confirmar o diagnóstico, sendo necessária realização de perfil imuno-histoquímico. Apesar de incomum, o diagnóstico de doença de Paget deve ser lembrado como diferencial de melanoma em lesões pigmentadas dessa região, em ambos os sexos.

Combined High-Grade Basal Cell Carcinoma and Malignant Melanoma of the Skin (???Malignant Basomelanocytic Tumor???)

We describe two cases of a malignant cutaneous neoplasm with combined phenotypical features of high-grade basal cell carcinoma and malignant melanoma. Some tumor cells showed a keratinocytic phenotype (cytokeratins, p63) and others a melanocytic phenotype (HMB-45, MART-1, Melan-A, S100-protein). We favor the hypothesis of a tumor with bidirectional keratinocytic and melanocytic differentiation, an exceptionally rare event.

Different Manifestations of Malignant Melanoma in the Breast: a Report of 12 Cases and a Review of the Literature

BACKGROUND

The breast is associated with a large number of diseases. Besides being the host of many benign and malignant tumors, breast skin and parenchyma are also metastatic sites for various tumors such as leukemia, lung cancer and melanoma.

METHODS

Malign melanoma has different manifestations in the breast. All these manifestations are important not only as initial presentations of the disease, but also as indicators of the progression period of the disease.

RESULTS

This study reports on 12 cases of cutaneous malignant melanoma in breast skin and tissue. Nine of these cases are primary cutaneous melanomas, while the others are breast metastases from a distant site cutaneous melanoma. In two of the nine primary cutaneous melanomas in-transit metastasis to the breast developed during the follow-up period.

CONCLUSIONS

In this paper, the diagnostic and surgical approach to primary and metastatic melanoma of the breast, and the importance of the breast during the follow-up period are reviewed.

Lineage infidelity of MDA-MB-435 cells: expression of melanocyte proteins in a breast cancer cell line

The origin of cell lines is critical in defining cell type-specific biological functions. Several reports suggested that the MDA-MB-435 cell line, a cell line extensively used for studying breast cancer biology, has a gene expression pattern most compatible with melanocyte origin. However, we demonstrate that MDA-MB-435 cells express breast-specific or epithelial-specific markers. Also, MDA-MB-435 cells were induced to express breast differentiation-specific proteins and secrete milk lipids as observed in other well-established breast cancer cell lines. Notably, MDA-MB-435 cells also expressed melanocyte-specific proteins as did another highly aggressive breast cancer cell line. MDA-MB-435 xenograft tissue sections stained entirely positive for epithelium-specific markers but only partially positive for melanocyte-specific markers. Thus, MDA-MB-435 is most likely a breast epithelial cell line that has undergone lineage infidelity.

Epidermotropic metastases from breast carcinoma showing different clinical and histopathological features on the trunk and on the scalp in a single patient

A 54-year-old female presented with the cutaneous metastases of the breast carcinoma that produced combination of pigmented zosteriform eruption on the trunk and eroded plaque on the scalp, 13 years after radical mastectomy. Histologically, zosteriform lesions displayed prominent infiltration of the epidermis in nesting or linear pattern by neoplastic cells with focal formation of intraepidermal and subepidermal vesicles due to discohesion of tumor cells and dermal edema. Examination of scalp plaque revealed ulcerations and infiltration of the epidermis with scattered basal and suprabasal malignant cells in pagetoid fashion. Immunohistochemically, tumor cells were cytokeratin 7- and estrogen receptor-positive and cytokeratin 20 negative. HMB-45 and Melan-A-stained numerous dendritic melanocytes intermingled with intraepidermal and superficial dermal tumor cells in the trunk lesion, whereas on the scalp, only occasional melanocytes surrounding intraepidermal carcinomatous cells were identified. Our case described, to our knowledge, so far unreported combination of individually rare, clinical and histological patterns of cutaneous metastases from breast carcinoma in a single patient.

Metaplastic carcinoma of the breast with rhabdomyosarcomatous element: aspiration cytology with histological, immunohistochemical, and ultrastructural correlations

We studied a metaplastic breast carcinoma with a rhabdomyosarcomatous element from a 62-yr-old woman. In the fine-needle aspirates processed by Ultrafast Papanicolaou stain, there were small undifferentiated cells with scanty cytoplasm and differentiated cells with red macronucleoli and abundant cytoplasm. Some differentiated cells contained a brown inclusion with a blue rim. Ultrastructurally, the brown inclusion correlated to a central aggregate of sarcomeres and the blue rim correlated to actin filaments surrounding the sarcomeres. The differentiated cells without cytoplasmic inclusions expressed cytokeratin and contained tonofilaments. A transitional cell type containing both sacromeres and tonofilaments was absent. Immunohistochemically, the small undifferentiated cells expressed vimentin diffusely and showed >90% MIB-1 proliferating index, whereas the differentiated cells expressed cytokeratin, actin, or myoglobin and had virtually absent MIB-1 nuclear labeling. Histologically, the small cells were more concentrated along the capsule and the large cells were more concentrated in the center of the tumor. These findings suggest the bidirectional differentiation of the small undifferentiated cells into carcinoma cells and rhabdomyosarcoma cells in this tumor.

Pigmented mammary Paget disease and pigmented epidermotropic metastases from breast carcinoma

Pigmented mammary Paget disease is a rare clinicopathologic variant of mammary Paget disease. It has been described in female and male patients with intraductal mammary carcinoma extending to the epidermis of the nipple and areola through a lactiferous duct. Pigmented cutaneous metastases from breast carcinoma are uncommon variants of epidermotropic metastatic breast carcinoma. All these lesions may mimic malignant melanoma clinically and histopathologically. From a histopathologic point of view, involvement of the dermoepidermal junction by neoplastic cells of the mammary carcinoma seems to be a prerequisite for development of the clinical pigmentation. We report three examples of pigmented mammary Paget disease and six cases of pigmented epidermotropic metastases from breast carcinoma, which were studied from both the histopathologic and immunohistochemical points of view. Two cases of pigmented mammary Paget disease and all cases of pigmented epidermotropic metastatic breast carcinoma showed the proliferation of dendritic melanocytes arranged as solitary units along the dermoepidermal junction and intermingled with the neoplastic cells of the mammary carcinoma in the superficial dermis. In one case of pigmented mammary Paget disease, there was abundant melanin within the cytoplasm of the Paget cells, but an increased number of melanocytes could not be demonstrated. Local production of melanocytic chemotactic factor by neoplastic cells of the mammary carcinoma when they reach the dermoepidermal junction has been postulated as the cause of the melanocytic proliferation and clinical hyperpigmentation of these epidermotropic breast carcinomas. Another possibility is the phagocytosis or transfer of melanin from melanocytes to the intraepidermal neoplastic cells of the breast carcinoma. Pigmented mammary Paget disease and pigmented epidermotropic metastatic breast carcinoma should be differentiated from melanoma clinical and histopathologically.

Mammary carcinoma with prominent cytoplasmic lipofuscin granules mimicking melanocytic differentiation

We report a case of mammary carcinoma with striking cytoplasmic pigmentation in a 60-year-old Japanese woman who presented with a self-evident nodular lesion in the left breast.

METHODS AND RESULTS

After a fine needle aspiration revealing atypical clusters of cells, an excisional biopsy was performed. Histologically, a partially cystic 18 mm lesion containing a 5-mm mural nodule was present. The mural nodule and adjacent thickened epithelium were comprised of atypical cells focally invading into the cyst wall. Striking abundant granular brown pigment resembling melanin was present in some of the neoplastic cells. The differential diagnosis included metastatic melanoma and mammary carcinoma with melanocytic differentiation. After a series of special stains and immunohistochemical studies, the diagnosis of mammary carcinoma with extensive cytoplasmic lipofuscin pigment was rendered.

CONCLUSION

Mammary carcinoma with lipofuscin pigment to the degree seen in this case which mimics melanocytic differentiation has not, to our knowledge, previously been documented.

Fine-needle aspiration of a metaplastic breast carcinoma with extensive melanocytic differentiation: a case report

Metaplastic carcinomas of the breast are uncommon breast tumors with aberrant cellular differentiation, most commonly showing ductal, squamous, and mesenchymal components. A breast carcinoma composed of both epithelial and melanocytic differentiation is rare, with only four previously reported cases in the literature. We present the fifth reported case, where the diagnosis was suggested by fine-needle aspiration (FNA) and later confirmed after the surgical specimen was excised. Histologically, this neoplasm revealed multidirectional differentiation, consisting primarily of squamous and melanocytic cell types, with focal glandular and osseous metaplasia. Based on the morphologic, immunohistochemical, and ultrastructural findings, we conclude that such tumors fall within the spectrum of metaplastic carcinomas of the breast. We believe that this case will further contribute to the understanding of this enigmatic tumor.

Pigmented carcinoma of the breast: an ultrastructural study

A pigmented skin lesion on a breast removed for carcinoma resembled melanoma by routine light microscopy, but correlation with immunohistochemistry and electron microscopy established that carcinoma cells within the upper dermis were intermingled with a proliferation of non-neoplastic melanocytic cells. Ultrastructurally, the tumor cells possessed desmosomes and intracytoplasmic lumina and mature melanosomes were present in their cytoplasm. The melanocytic cells were identified as melanocytes or melanophages, and it was concluded that the tumor in the skin was a passively pigmented carcinoma and not a melanoma or metaplastic breast carcinoma.

Breast carcinoma diverging to aberrant melanocytic differentiation: a case report with histopathologic and loss of heterozygosity analyses

A case of primary breast cancer showing differentiation to malignant melanoma is reported. To obtain insight into the clonal relationship between the two components of the tumor, polymerase chain reaction-based microsatellite analysis to detect loss of heterozygosity on chromosome arms 1p, 1q, 3q, 4q, 6q, 8p, 9p, 10q, 11q, 13q, 16q, 17p, 17q, and 18q with microdissected tissues of both components was performed in addition to histologic, histochemical, immunohistochemical, and ultrastructural techniques. The tumor consisted of a combination of carcinoma and melanoma with morphologic transition. Metastases in the lymph nodes and thoracic spinal bone marrow showed dual tissue structure. One of the metastatic lung tumors showed melanomatous tissue structure. The abundant pigment in the cells was positive for Fontana-Masson staining and bleached with potassium permanganate. The carcinoma component was positive for epithelial membrane antigen and CA19-9, but the melanoma component was negative. Conversely, the melanoma component was positive for HMB45 and vimentin, but the carcinoma component was negative. Electron microscopic analysis showed premelanosomes and melanosomes in the melanoma component. Microsatellite analysis showed the same genetic alterations with loss of heterozygosity on chromosome arms 1p, 3q, 4q, 6q, 9p, 10q, 11q, 13q, 16q, 17p, and 17q in in situ, invasive, and metastatic foci. We concluded that the carcinoma and melanoma components had arisen from the same clone and that this breast carcinoma might have diverged to aberrant malignant melanoma through multiple genetic alterations in the early period of ductal carcinoma in situ.

Dermal squamo-melanocytic tumor: a unique biphenotypic neoplasm of uncertain biological potential

We report four cases of an unusual cutaneous squamo-melanocytic neoplasm with histological features of malignancy and uncertain biological potential. These tumors developed on the face of middle-aged and older adults. Clinically, a purple-black nodule ranged in size from 3 to 10 mm in maximum diameter. After complete excision, neither recurrence nor metastasis has been observed (mean follow-up time, 3.25 years). Histologically, a discrete dermal nodule surrounded by a fibroblastic stroma was composed of large islands of mitotically active atypical epithelioid cells. The nodule was not connected to the epidermis in three of four cases. Two types of cells were either diffusely admixed or clustered in small groups within the nodule. Small, atypical, epithelioid cells containing finely granular brown pigment, proven to be melanin, constituted the first cell type. The second type consisted of atypical squamoid cells, some with abundant pink cytoplasm, giving rise to squamous pearls. A lentigo maligna was present in one case. The remaining three cases had neither significant intraepidermal melanocytic nor keratinocytic atypia. Immunohistochemical studies indicated that the melanin-containing epithelioid cells expressed S-100 antigens, and the squamoid cells expressed cytokeratins. A small population of tumor cells did not label with either of the antibodies. These four tumors (along with a previously reported, apparently identical tumor arising in the setting of lentigo maligna) represent a unique biphasic dermal neoplasm with histological features of malignancy but, at this time, uncertain biological behavior. Although none have recurred or metastasized, the follow-up time is too short in our estimation to guarantee a benign course. These neoplasms are easily recognized by their characteristic features. Further follow-up evaluations should allow determination of their biologic potential.