Treatment of primitive myxoid mesenchymal tumour of infancy: a management paradigm focusing on surgical nuances

Primitive myxoid mesenchymal tumour of infancy (PMMTI) is a rare mesenchymal tumour that typically appears in those under 6 months of age and preferentially affects the deep soft tissues of the trunk and paravertebral spinal regions. PMMTI has only recently been described, and there is scarce literature reporting cases regarding the management paradigm of the tumour. We report the case of an 11-week-old male who presented with bilaterally reduced movement and brisk reflexes in his lower limbs, and irritability. Despite numerous radiological investigations, including MRI, PMMTI was only diagnosed upon biopsy and histopathology. Although PMMTI is known to be relatively unresponsive to chemotherapy, we observed a notable decrease in tumour size after a series of chemotherapy sessions. After two-staged surgical resection of the tumour, the patient is currently stable and under close follow-up. In this article, we aim to report on the patient's clinical presentation, investigations, diagnosis, and treatment, while also discussing the findings from a review of the literature pertaining to future approaches in managing PMMTI. Overall, this case highlights the importance of considering PMMTI in the differential diagnosis of deep soft tissue tumours in young infants and the potential for a combination of chemotherapy and surgical resection to be effective in treating this rare tumour.

Epithelioid myofibroblastoma with concurrent presentation of LCIS and DCIS

Myofibroblastoma (MFB) of the breast is a rare benign neoplasm of the mammary stroma. Several morphologic variants have been described in the literature, which can create diagnostic challenges for pathologists, in particular the epithelioid variant of MFB, which can mimic invasive lobular carcinoma. We report a case of a 72-year-old female who presented for a painless breast lump and was later found to have 2 lesions on imaging, with 1 lesion corresponding to the palpable lump and the other lying in a different quadrant. Core-needle biopsies demonstrated ductal carcinoma in-situ at both lesional sites with what was originally felt to be an invasive lobular carcinoma at the lesional site which did not correspond to the palpable lump. After mastectomy, with more complete visualization microscopically of the lesional area originally felt to be an invasive lobular carcinoma, the final pathology was consistent with a MFB, predominantly epithelioid variant, in addition to ductal carcinoma in-situ and lobular carcinoma in-situ. In this paper we describe the imaging findings of an epithelioid MFB and how its nonspecific nature necessitates close communication between the radiologist and pathologist to make the correct diagnosis.

A giant superficial myofibroblastoma involving the vagina and pelvis: A case report and review of the literature

Superficial myofibroblastoma is a rare benign mesenchymal tumor that presents a challenge in accurate preoperative diagnosis because of its overlapping radiological and histological features. A 27-year-old woman presented with a history of increasing abdominal girth over the prior year and pelvic mass for 1 month. Imaging confirmed the presence of a giant well-circumscribed cystic-solid tumor involving both the extraperitoneal pelvis and vagina. After exploration and excision, superficial vaginal myofibroblastoma was diagnosed pathologically. The patient underwent surgical excision and had no postoperative complications at the 1-month follow-up. Imaging features and clinical reasoning can aid in differentiating superficial myofibroblastoma from more aggressive entities or malignant tumors and guide suitable and appropriate surgical approaches.

Mammary myofibroblastoma: Presentation of case

INTRODUCTION AND IMPORTANCE

Mammary myofibroblastoma (MFB) is a rare benign mesenchymal lesion. It belongs to the family of benign spindle cell tumours of the mammary stroma and may exhibit confusing variants. Some of them may mimic invasive tumours, leading to the diagnostic dilemmas, especially in core needle biopsy specimens or frozen sections. Familiarity with the characteristics of this tumour is of great importance for accurate diagnosis and proper treatment.

CASE PRESENTATION

We report about a rare form of CD34-negative mixed epithelioid/lipomatous form of mammary myofibroblastoma in a 48-year-old Caucasian premenopausal woman with no previous medical history. Breast imaging suggested a benign lesion. The core needle biopsy suggested breast MFB. The definitive diagnosis was established through histopathology and immunohistochemistry of the lumpectomy specimen.

CLINICAL DISCUSSION

Despite its rarity, breast MFB is a disease with a wide spectrum of histologic morphologies. CD34 positivity is seen in majority of MFB cases. MFBs uncommonly show absent expression of CD34, a potential diagnostic pitfall, just like in our case.

CONCLUSION

Pathologists should recognise the wide range of differential diagnoses and be familiar with the diverse morphological appearances of these lesions to make an accurate diagnosis. Surgical excision is at present the ordinary treatment of MFB.

Male breast myofibroblastoma: Imaging features and ultrasound-guided core biopsy diagnosis

Mammary myofibroblastoma is a rare mesenchymal neoplasm that typically presents in older men and women. Less commonly, these benign tumors may also occur in soft tissues located outside of the breast, in which case they are referred to as mammary-type myofibroblastomas. The histologic composition of this benign spindle cell tumor can be markedly varied. We present one such case of myofibroblastoma of the male breast, describing its sonographic appearance and its diagnosis using ultrasound-guided core biopsy.

Epithelioid myofibroblastoma of the breast: A case report and review of the literature

INTRODUCTION

Mammary myofibroblastoma (MFB) is a rare tumour. Its clinical and pathologic characteristics have been only sporadically described. A case of epithelioid variant of MFB is reported with the diagnostic tips, the differential diagnoses, and a discussion on the possible pathogenesis.

PRESENTATION OF CASE

A 74 year-old woman presented with a painless nodule in the left breast. Core needle biopsy (CNB) revealed a tumour primarily composed of epithelioid cells. Despite epithelioid appearance of the tumour cells, ductal/lobular components were absent within the tumour. As cell lineage of the epithelioid cells could not be determined with CNB, lumpectomy was performed to obtain definitive diagnosis and, at the same time, to remove the lesion. Histologically, the tumour consisted of multiple epithelioid cell nests that were spread over fibrous stroma infiltrated with adipose tissue. Spindle cells were also present, but they were fewer than epithelioid cell clusters. Occasionally, the tumour cells showed nuclear atypia. It was difficult to determine whether this tumour was benign or malignant solely with Hematoxylin-eosin stain. However, with the aid of immunohistochemical analyses, we could make a histodiagnosis of epithelioid subtype of myofibroblastoma.

DISCUSSION

The differential diagnoses of epithelioid MFB include ductal, lobular, metaplastic carcinomas and mesenchymal tumours. Comprehensive knowledge of classic and variant MFB is necessary for the correct diagnosis.

CONCLUSION

Pathologic diagnosis of epithelioid variant of MFB requires careful evaluation of histology and the use of a panel of immunohistochemistry. Female phenotype of breast stroma may play a role in the pathogenesis of MFB.

Cellular angiofibroma arising in the anorectal region: clinicopathologic and immunohistochemical analysis of five cases

Cellular angiofibroma (CA) is a rare, benign mesenchymal tumor with a predilection to the distal female and male genital tract. Extragenital examples of CA, including anorectal CAs, are exceedingly rare and documented mainly as single case reports. Herein, we analyze the clinicopathological and immunohistochemical features of 5 anorectal CAs. There were 4 males and one female ranging in age from 45 to 70 (median, 58) years at the time of surgery. Tumors arose in the superficial tissues of the anorectal (n = 3) and perianal (n = 2) regions. The tumors were well circumscribed ranging from 2 to 6.7 (median, 5.4) cm. All demonstrated a low to moderately cellular proliferation of cytologically bland spindled cells within a variably dense collagenous and focally myxocollagenous stroma and small- to medium-sized vessels featuring perivascular collagen deposition. Two cases showed degenerative and/or inflammatory changes. All 5 tumors strongly expressed CD34 and androgen receptor proteins, more variably expressed estrogen (n = 5) and progesterone (n = 4) receptor proteins and desmin (n = 3), and focally expressed alpha-smooth muscle actin (n = 3), GATA-3 (n = 2), and p16 (n = 1). Retinoblastoma protein expression was reduced (n = 4) (compared with expression in endothelial cells) or completely lost (n = 1). All patients were treated with simple surgical excision, and the 2 study members with follow-up data showed no evidence of local recurrence over a postoperative follow-up interval of 23 and 73 months. In comparison with conventional genital tract CA, our 5 anorectal CAs occurred mostly in males, were generally less cellular, and appear to follow a similar uneventful clinical course.

Myofibroblastoma of the Breast: A Morphologic and Immunohistochemical Study of Three Cases

Myofibroblastoma (MFB) of the breast is an uncommon entity of benign spindle neoplasms of the breast. This tumour possesses a broad spectrum of histomorphological patterns. Distinguishing of myofibroblastoma variants from malignant mimics of this benign neoplasm is essential for pathologists to avoid further invasive surgical procedures. In this article, we report the clinical, morphological, and immunohistochemical features of three cases, including two females and one male patient with mammary myofibroblastoma with emphasis on the histomorphological findings. As there is not yet enough information about MFB, more reports of MFB are still required to more clarify the pathogenesis and potential predisposing factors of this rare type of breast tumours.

A Rare Case of Epithelioid Myofibroblastoma of Breast Mimicking Lobular Carcinoma on Trucut Biopsy: a Diagnostic Pitfall and Literature Review

Epithelioid myofibroblastoma of the breast is a rare benign stromal tumor occurring in the postmenopausal females and elderly males. We report one such case in a 65-year-old female who underwent trucut biopsy from a well-defined right breast lump, which was misinterpreted as invasive lobular carcinoma on histology. Tumor showed mild to moderately pleomorphic tumor cells arranged in single file pattern, loosely dispersed and focally in sheets with inconspicuous nucleoli embedded in a fibrotic and hyalinized stroma. Immunohistochemistry for E-cadherin was negative further substantiating the morphological diagnosis. However, mastectomy specimen revealed it to be a case of epithelioid myofibroblastoma with the help of a large panel of immunohistochemical stains. In this report, we emphasize on the challenges of establishing this rare diagnosis mimicking lobular carcinoma, a diagnostic pitfall on trucut biopsy.

[Extramammary myofibroblastoma affecting the pelvic region: a case report]

Un myofibroblastome de type mammaire est une tumeur molle rare; les myofibroblastomes extramammaires sont particulièrement rare. Un homme de 78 ans s'est présenté en consultation pour des douleurs pelviennes soulagées par la défécation ou les urines. Le toucher rectal retrouve une masse en avant de la paroi rectale antérieure. L'imagerie par résonance magnétique (IRM) montre une masse de 10 x 6 x 8cm, bien circonscrite et hétérogène, située en arrière de la vessie qu'elle refoule vers l'avant, en avant du recto-sigmoïde. L'immunohistochimie montre des cellules tumorales co-exprimant CD34 et la desmine de façon diffuse, expression de Rb dans la majorité des cellules, expression des récepteurs aux œstrogènes, expression intense et diffuse de la P16, un index de prolifération avec le ki67 estimé à 25%. Il n'y a pas eu de récidive après 8 mois de radiothérapie d'induction suivie de chirurgie. Un myofibroblastome de type mammaire est une tumeur rare et bénigne. La récidive n'est quasiment pas observée après traitement local. Ce cas permet de mettre en avance la possibilité d'utiliser la radiothérapie afin de faciliter la chirurgie.

Clinicopathological and radiological characterization of myofibroblastoma of breast: A single institutional case review

Myofibroblastoma is a rare type of benign myofibroblastic neoplasm in the breast. It is clinically presented as a well-circumscribed mass, usually small in size (usually less than 4.0 cm), and can mostly be cured by local excision. Rare cases of giant myofibroblastoma greater than 10 cm have been reported, but also follow a benign clinical course. Histologically, breast myofibroblastoma is featured by bland fascicles of spindle cells intermixed with thick hyalinized collagen bundles. Mast cells are frequently found within the stroma. However, a wide spectrum of morphological variants can occur in myofibroblatoma, making its diagnosis challenging sometimes. Differential diagnosis of myofibroblastoma with other spindle cell lesions in the breast, either benign or malignant, is also important in practice. In this study, we collected 15 cases of breast myofibroblastoma diagnosed in our institution during a 20 year period. The sizes of these cases range from 0.4 cm to 35.2 cm (mean is 3.7 cm). To our knowledge, the case of giant breast myofibroblastoma we presented here is the largest one reported to date. The histological examination of the cases show great morphological variations. Besides the classical type, features of cellular, collagenized, palisading, epithelioid, myxoid, myoid, solitary fibrous tumor-like are also identified in the case series. Immunohistochemical staining patterns as well as clinical features of the cases are also summarized and compared. All cases in this study show no recurrence on follow-up. In addition, cases that are important differential diagnosis for breast myofibroblastoma are also studied. Their key histological characteristics are compared with myofibroblastoma, and their immunohistochemical and molecular features are discussed.

Chromosomal microarray analysis of benign mesenchymal tumors with RB1 deletion

Spindle cell lipomas/pleomorphic lipomas, mammary-type myofibroblastomas, and cellular angiofibromas are benign mesenchymal tumors that demonstrate histologically overlapping features but with varying anatomic locations and an uncertain etiologic relationship. These tumors have also been found to have an overlapping molecular profile with shared 13q14 deletions, which is the location of the tumor suppressor gene RB1 that encodes the retinoblastoma protein. Molecular studies thus far have largely focused on the RB1 locus, using primarily immunohistochemistry and fluorescence in situ hybridization to characterize RB1 status. However, further characterization of the molecular profile of these lesions, including genome-wide copy number variation, remains to be well defined. The goal of this study is to further characterize the specific RB1 deletions seen in spindle cell lipomas/pleomorphic lipomas, cellular angiofibromas, and mammary-type myofibroblastomas as well as to evaluate these neoplasms for additional molecular abnormalities using the OncoScan™ CNV Plus Assay, which is used for clinical use as a whole-genome copy number microarray-based assay. Ten of eleven cases demonstrated deletion of the RB1 gene with varying deletion size and breakpoints. The majority of additional genetic alterations were chromosomal losses and loss of heterozygosity with rare chromosomal gains. Although only a small subset of mesenchymal neoplasms was evaluated, the principle of creating a novel pairing of the molecular method with the tumor type represents a promising avenue for further study in a variety of tumors.

A novel collision tumour of myofibroblastoma and low-grade adenosquamous carcinoma in breast

BACKGROUND

Myofibroblastoma (MFB) and low-grade adenosquamous carcinoma (LGASC) are rare tumours in the breast, respectively. However, a collision tumour of the two types has never been reported.

CASE PRESENTATION

A 42-year-old female presented with a palpable mass in diameter of about 2.5 cm in the left breast. Morphologically, the lesion was predominately composed of bland spindle cells admixed with some islands of mature adipocytes and a few epithelial elements dispersing in infiltrating way which formed both tubule and solid structures. The mass showed low positive index of Ki-67. The spindle cells were strongly and diffusely positive for CD34, SMA, desmin, ER and PR. The epithelial elements were positive for CK and EMA, and negative for ER and PR completely. CK5/6 and P63 were positive in the outer-layer of the tubules and nearly all the cells of the solid nests.

CONCLUSIONS

A collision tumour of MFB and LGASC in breast is extremely rare and either component is supposed to be not overlooked. Excision and close follow-up are advised.

A rare case of intranodal hemorrhagic spindle cell tumor with amianthoid fibers presenting as a suspicious lump in the groin

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Hemorrhagic spindle cell tumor with amianthoid fibers is extremely rare.

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The present case adds to the very limited data available on this entity.

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The tumor in the present case reached a relatively large size and raised clinical suspicion for lymphoma.

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This tumor is a mimicker for many benign and malignant conditions.

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This tumor must be considered to avoid the misinterpretation as primary malignant spindle cell lesion or metastasis.

Introduction

Intranodal hemorrhagic spindle cell tumor with amianthoid fibers is extremely rare.

Presentation of the case

Herein, we present the case of a 58-year-old man with a 2-year history of painless left inguinal swelling. On physical examination, the mass was large, fixed, hard, and non-tender, suggesting a lymph node pathology. The mass had increased slightly in size after a short course of antibiotic treatment. The surgeon decided to perform an excisional biopsy of the left inguinal lymph node. The lesion was intraoperatively hard and suspicious for malignancy. The gross examination revealed a relatively large well-circumscribed mass with a whitish, hard, cut surface. The histomorphological and immunohistochemical findings were consistent with intranodal hemorrhagic spindle cell tumor with amianthoid fibers. There was no evidence of recurrence at 4 years post surgery.

Discussion

The present case adds to the very limited data available on this rare entity.

Conclusion

Intranodal hemorrhagic spindle cell tumor with amianthoid fibers can be a diagnostic pitfall both clinically and histopathologically. It can reach large sizes and be clinically and grossly suspicious for lymphoma. Clinicians must be made aware that such an entity exists.

Multimodality images of myofibroblastoma in the male breast: A case report and a review of the literature

We report a case of a 58-year-old male diagnosed with myofibroblastoma using mammography, ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI), as well as present a review of the literature. The pathological diagnosis was myofibroblastoma with spindle cell neoplasm with immunoreactivity. Myofibroblastoma is a rare benign disease and there is a lack of reports of multimodality imaging of this disease. We review the imaging features of this rare disease across multiple imaging modalities with pathological correlation, and provide current treatment recommendations as well.

Myofibroblastoma of the Breast: A Rare Cause of Breast Lump in a Postmenopausal Woman

A breast mass in a postmenopausal age woman is treated with a high index of clinical suspicion for malignancy. Myofibroblastoma (MFB) of the breast is a very rare benign stromal tumor, predominantly occurring in menopausal women and older men. Owing to its rarity, nonspecific radiology, cytomorphology, and many variants, it can be confused with other malignant and benign breast lesions and hence can be a source of diagnostic pitfall. We present a case of an MFB of the breast in a 55-year-old female, which was detected on a routine screening mammography. Fine-needle aspiration cytology was inconclusive. Final diagnosis was made by histopathology and immunohistochemistry examination. We report this case as the likelihood of encountering MFB has increased in recent years due to routine mammographic screening, and this lesion should be kept in the differential diagnosis of spindle-cell lesions of the breast.

Cervical superficial myofibroblastoma: Case report and review of the literature

Superficial myofibroblastoma of the lower female genital tract is a rare benign, recently recognized neoplasm that mostly affects the vulvovaginal area. Our report discusses a case of cervical superficial myofibroblastoma of the lower female genital tract in a 45-year-old patient who is presented with menometrorrhagia. On examination, she had multiple uterine fibroids and a circumscribed submucosal mass lesion involving the anterior lip of cervix. At hysterectomy, histopathological examination of the cervical mass revealed a relatively hypocellular tumor consisted of bland spindled and stellate cells. An immunohistochemistry evaluation revealed reactivity for CD34, desmin, and smooth muscle actin. This neoplasm should be included in the differential diagnosis of cervical mass lesions. This tumor also needs to be differentiated from other mesenchymal lesions of lower female genital tract.

Imaging features of mammary-type myofibroblastoma of soft tissue: a case series with literature review

Mammary-type myofibroblastoma (MTM) is a rare, benign neoplasm that is histologically identical to myofibroblastoma of the breast, but occurring in an extramammary site. The masses have been reported in superficial and deep soft tissue sites and visceral locations with the inguinal area and lower extremities are the most common. Most previous reports of MTMs have concentrated on clinical and pathological findings, with very limited information regarding imaging characteristics. Here, we describe three cases of MTM diagnosed at our institution, with a focus on imaging findings. We compare our findings with previously reported cases. Although MTM is rare, radiologists should be aware of this benign diagnosis as imaging characteristics can mimic those of liposarcomas and atypical lipomatous tumor/well-differentiated liposarcoma. Unlike those tumor types, MTM virtually never recurs post-resection, even when there are positive margins. Biopsy is necessary for proper diagnosis and recommended as an initial step to avoid overly aggressive treatment.

Radiologic presentation of a myofibroblastoma of the adult male breast

We present the case of a 50-year-old male with bilateral gynecomastia who was incidentally found to have 0.8-cm subareolar mass on computed tomography. Mammographic and sonographic characteristics of the lesion are described as well as a brief historical review of myofibroblastoma, a rare mesenchymal tumor.

Chondrolipoma of the breast as a rare variant of myofibroblastoma: an immunohistochemical study of two cases

Chondrolipoma of the breast is a very rare tumor whose histogenesis remains obscure. We report two cases (56-year-old and 43-year-old women) and present the results of an immunohistochemical study which strongly suggests that this tumor is a variant of myofibroblastoma. The tumors predominantly consisted of lipoma-like, mature adipose tissue, and many islands of hyaline cartilage. A proliferation of spindle cells associated with the deposition of collagen fibers was also seen. On immunohistochemical examination, spindle cells showed cytoplasmic reactivity for vimentin, desmin, bcl-2, and α-smooth muscle actin, as well as nuclear reactivity for estrogen receptor (ER) and progesterone receptor (PgR). Chondrocytes were immunoreactive for ER, PgR, S-100 protein, and Sox9. The nuclei of adipocytes, chondrocytes, and spindle cells were not immunoreactive for Rb (retinoblastoma) protein. The immunoreactivity of spindle cells for muscle markers indicates myofibroblastic differentiation, and the lack of the nuclear expression of Rb protein suggests the close relationship of this tumor with myofibroblastoma and spindle cell lipoma. The immunoreactivity of chondrocytes for ER and PgR suggests that they are derived from metaplasia of hormone-sensitive spindle cells. These findings support the concept that chondrolipoma of the breast could be a lipomatous variant of myofibroblastoma associated with cartilaginous metaplasia and that it should be added to members of the "13q/Rb family of tumors."

Myofibroblastoma

Myofibroblastoma of the breast is a rare benign mesenchymal tumor. We report a 61-year-old male case who presented to the orthopedic clinic with right shoulder pain. The physical and clinical examination was normal and he was referred to our clinic. Excision was performed and there were no postoperative complications.

Myofibroblastoma of the male breast: a rare entity with radiologic-pathologic correlation

A 73-year old man with a history of multiple genitourinary malignancies was found to have a left retroareolar soft tissue mass on CT assessment of disease, and dedicated breast imaging was recommended. Diagnostic mammography and ultrasonography confirmed a solid mass, for which biopsy was recommended. Pathologic analysis demonstrated a spindle cell neoplasm with an immunoreactivity pattern consistent with myofibroblastoma. While this entity is benign, nonspecific imaging features necessitate tissue sampling for pathologic diagnosis, and, given pathologic rarity, open communication between the radiologist and pathologist is important to establish the correct diagnosis and to recommend appropriate management.

Intracranial Cystic Myofibroblastoma: a Case Report with Literature Review

BACKGROUND

Myofibroblastoma is a rare benign soft tissue tumor comprised of contractile myiod cells mostly in mammary gland. Only 4 prior cases arising in the central nervous system have been reported in the literature. We present a case of myofibroblastoma with a cystic component.

CASE DESCRIPTION

The patient is a 76-year-old man with a history of Parkinson disease. The tumor was found incidentally after a minor fall. Magnetic resonance imaging revealed a 6.7-cm well-circumscribed, partly cystic mass with a 2.4-cm calcified central nodule located at the left sylvian fissure. The frontal dural base showed avid enhancing after gadolinium injection. Gross total resection was achieved. The tumor was marked by dense collagenous tissue and bland spindled cells in pathology review. The spindled cells demonstrated positive staining with antibodies to CD34, estrogen receptor, and smooth muscle actin. A blush of immunoreactivity is observed in scattered cells with antibody to progesterone receptor. Patient recovered well postoperatively.

CONCLUSIONS

This is a rare condition of a benign soft tissue tumor of mammary gland presented primarily in the brain. The literature on myofibroblastomas arising in the central nervous system is reviewed.

Myofibroblastoma of the mandible in a 3-year-old child

Myofibroblastoma is a rare benign tumor of the head and neck region, which is characterized by a large, rapidly growing, and destructive mass. A 3-year-old boy presented with an 8-week history of a rapidly growing swelling of the right mandible. Examination revealed a firm 13-cm mass occupying the entire right body and ramus of the mandible. The clinical and radiological features were suggestive of a sarcoma. An initial biopsy taken in the referring hospital was inconclusive, and the second biopsy showed a myofibroblastic neoplasm consistent with a desmoplastic fibroma. Progressive tumor growth necessitated a tracheostomy. Right hemimandibulectomy was performed, and the defect was reconstructed with free microvascular fibula flap. Histopathology and immunocytochemistry revealed a myofibroblastoma. This entity differs from other myofibroblasts and fibroblast tumors such as inflammatory myofibroblastic tumor (IMT), myofibroma, and desmoplastic fibroma. The child has been followed up for 2 years.

CONCLUSION

Differentiation between myofibroblasts and fibroblastic tumors as well as some malignancies can be challenging. Myofibroblastoma can behave as a malignant neoplasm, and the clinical distinction of this entity lies primarily in its recognition as a benign neoplasm.

Myofibroblastoma of the Breast

This study aimed presenting a case of a 64-year-old woman with a rare diagnosis of myofibroblastoma (MFB). MFB is one of the rare, benign, spindle-like stromal tumors arising from the connective tissue of the breast. MFBs are often confused with fibroadenomas and hamartomas because of their benign characteristic appearance on breast imaging and are diagnosed after excisional biopsies. Their differential diagnosis with malignant neoplasia of the breast is important because of their wide morphological spectrum. Our case also demonstrated a breast mass with benign imaging characteristics and a needle core biopsy revealing a benign, spindle-like stromal tumor. The pathological examination performed after the excision of the lump demonstrated a collagenous-/fibrous-type MFB. This case report emphasizes the rare but important place of MFB variants of the breast in the differential diagnosis of breast mass.

Nodular Mucinosis of the Breast in a Male: Reassessment of Diagnostic Criteria and Proposal for Its Classification as a Soft Tissue Tumor in the Myofibroblastoma and Spindle Cell Lipoma Spectrum

Nodular mucinosis of the breast (NMB) is a rare entity with only a few cases described in the literature, most of them in young girls. All cases are located in the nipple and areolar area and microscopically consist of a multinodular myxoid mesenchymal proliferation. Bands of sclerotic collagen containing preexisting breast ducts and abundant vascularization are other features typical of NMB. No relation to Carney complex has been reported, and an indolent behavior is the rule in all patients. We present a case of NMB occurring in the nipple of a 46-year-old man and analyze the clinicopathological features of the other cases of NMB reported in the English literature, concluding that two of them most likely correspond to trauma-induced cutaneous focal mucinosis of the mammary areola. Finally, we review diagnostic criteria for NMB and elaborate an ontogenetic hypothesis based on both its morphological resemblance to myofibroblastoma and its immunohistochemical profile.

Wilms' tumor protein (WT1) in mammary myofibroblastoma: an immunohistochemical study

Wilms' tumor protein (WT1) has been immunohistochemically detected in the cytoplasm of some developing, adult normal and neoplastic human tissues, suggesting its complex regulator activity in transcriptional/translational processes. Among neoplastic tissues, WT1 has been documented in the cytoplasm of benign and malignant vascular tumors and in rhabdomyosarcoma, while there are no available studies about its expression in myofibroblastic tumors. Accordingly, we studied immunohistochemically the potential expression of WT1 in mammary myofibroblastoma (MFB), a prototypical myofibroblastic tumor. A series of 18 cases of mammary MFB, including several morphological variants (classic, fibrotic, myxoid, lipomatous, Schwannian-like, and epithelioid variants), were tested with antibodies against the N-terminal of WT1. The most striking finding was a diffuse and strong WT1 cytoplasmic immunostaining restricted to the "epithelioid cell MFB", a rare and diagnostically challenging variant. Conversely the other variants of MFB, including the classic-type, were negative or only focally positive. The present study shows that mammary epithelioid cell MFB should be added to the list of mesenchymal tumors which express WT1 in the cytoplasm of neoplastic cells. Accordingly, we suggest that the detection of WT1 cytoplasmic immunoreactivity is of complementary diagnostic value to conventional myofibroblastic markers in identifying epithelioid cell myofibroblastoma.

Myofibroblastoma breast with unusual morphological features. Cytohistopathogical diagnostic pitfalls and role of immunohistochemistry-review of literature

Myofibroblastoma (MFB) is a rare mesenchymal tumour, derived from mammary stromal fibro-myofibroblasts, with diverse biological and morphological behaviour. Large and cellular myofibroblastomas, especially those with epitheliod like cells, can mimic various spindle cell lesions and metaplastic carcinomas, thus posing diagnostic challenge. A 50-year woman presented with slow growing, painless lump in the left breast. Fine Needle Aspiration (FNA) smears showed predominant atypical spindle cell population, pleomorphic epithelial like cells and giant cells. Cytodiagnosis of atypical spindle cell lesion with the possibility of metaplastic carcinoma was suggested. Histopathological examination showed fascicles of spindle cell population admixed with epithelial like cells, atypical cells and tumour giant cells, thus raising differential diagnosis of metaplastic carcinoma, low grade spindle cell sarcoma and myofibroblastic tumour. Lymph nodes were negative for metastatic deposits. Immunohistochemistry revealed variable coexpression of markers for vimentin, fibronectin, CD34, SMA (smooth muscle actin), but negative expression for , S-100, CD99, CK7 (cytokeratin 7), HMWK (high molecular weight keratin), ER (oestrogen receptor) and PR(progesterone receptors). Diagnosis of cellular myofibroblastoma with mixed unusual morphological features was defined, based on both histological and immunohistochemical features. MFB may cause a potential diagnostic pitfall while interpreting FNA and histopathological sections due to its wide differential diagnosis. The distinction of MFB from its cytohistological mimics of malignancy is crucial to avoid unnecessary extensive procedures. The case report emphasizes the role of immunohistochemistry as gold standard in diagnosis of MFB. The case is also being presented because of its large size and rare mixed unusual morphological features.

Atypical epithelioid cell myofibroblastoma of the breast with multinodular growth pattern: a potential pitfall of malignancy

Myofibroblastoma (MFB) of the breast is the prototypical benign spindle cell tumor arising from the mammary stroma. Over the last two decades, several morphological variants of this tumor have been recognized. Epithelioid cell MFB is composed predominantly of neoplastic elements with epithelioid morphology. It represents a potential diagnostic pitfall of malignancy, especially when evaluating small biopsies. We report a unique case of a mammary epithelioid cell MFB composed of large mono- to multi-nucleated cells showing mild to moderate nuclear pleomorphism, predominantly arranged in a multinodular growth pattern. This tumor needs to be distinguished from invasive apocrine, oncocytic, pleomorphic lobular carcinoma, as well as metastases. Immunohistochemistry revealed the fibroblastic/myofibroblatic (positivity for vimentin, desmin, CD34 and focally for α-smooth muscle actin) nature of proliferating cells, and therefore was crucial for a correct diagnosis.

Myofibroblastoma of the Breast: Diagnostic Challenges of a Rare Benign Tumor

Breast myofibroblastomas (MFBs) are rare benign tumors that have recently been recognized as a distinct entity. They are more common in men and often coexist with gynecomastia. Fine needle aspiration cytology or core biopsy should always be performed for triple assessment; however, due to the multiple variants of the tumor, final diagnosis can be safely accomplished only postoperatively with the aid of immunohistochemistry. The main histological characteristic that differentiates MFBs from the majority of malignant mesenchymal breast lesions is the presence of spindle cells in a collagenous background. Low mitotic activity and vimentin and CD34 positivity have been reported as well. Surgical excision retains a pivotal diagnostic and curative role. Local resection is sufficient, but mastectomy can also be advocated either in cases of male patients with coexisting gynecomastia or in females with large tumors. Into this retrospective survey, three cases of breast MFB were consecutively enrolled. Two patients were postmenopausal females and one was male. Relevant literature is briefly reviewed. Clinical features, histogenesis, morphological, and immunochemical findings are discussed, while the role of the current diagnostic and therapeutic management of this uncommon neoplasm is emphasized.

A rare case of hilar lymph node schwannoma

Schwannoma arising in a lymph node is an extremely rare primary mesenchymal tumor of the lymph node. Although intranodal schwannoma is benign, this lesion in a lymph node may be initially alarming and it may suggest a diagnosis of intranodal metastasis from a spindle cell tumor. Microscopic examination of tumor shows Antoni A areas, which are moderate to highly cellular areas of elongated cells arranged in fascicles, and Antoni B areas, which are hypocellular areas with myxoid and microcystic change. Tumor cell morphology is similar in both areas with elongated shape and regular oval nuclei. Immunohistochemistry report shows strong and diffuse positivity for S-100 which is consistent with Schwann cell origin. We report a rare case of intranodal schwannoma arising in the hilar lymph node with its clinical, light microscopic, and immunohistochemical findings.

Myofibroblastoma of the breast: Case report and literature review

Myofibroblastoma of the breast is a rare benign mesenchymal tumor. The literature describes relatively few cases of this type of tumor. We report on a new case of myofibroblastoma in a 65-year old man successfully managed at our institution. The purpose of this case report is to highlight characteristics and differential diagnosis of this rare neoplasm.

Spindle Cell Lesions of the Breast

Spindle cell lesions of the breast represent a heterogeneous group of reactive and neoplastic disorders that commonly present diagnostic challenges. Arguably, the most important of these lesions to recognize is spindle cell carcinoma, a type of metaplastic carcinoma. This review focuses on those spindle cell lesions of the breast that are most likely to be encountered in clinical practice or that produce particular diagnostic difficulties.