Hamartoma of the breast: a clinicopathological review

I saw the "breast within a breast" sign

The "breast within a breast" sign is used to describe the appearance of a breast hamartoma, also known as a fibroadenolipoma. A breast hamartoma is a benign mass made up of the same tissues that are found in a normal breast, giving the appearance of a breast within a breast on mammography. The "breast within a breast" sign is pathognomonic for a breast hamartoma and can help confidently diagnose these masses as benign without the need for further imaging or biopsy.

AMBRA1 p.Gln30Arg Mutation, Identified in a Cowden Syndrome Family, Exhibits Hyperproliferative Potential in hTERT-RPE1 Cells

Cowden syndrome (CS) is a rare autosomal dominant disorder associated with multiple hamartomatous and neoplastic lesions in various organs. Most CS patients have been found to have germline mutations in the PTEN tumor suppressor. In the present study, we investigated the causative gene of CS in a family of PTEN (phosphatase and tensin homolog deleted on chromosome 10) -negative CS patients. Whole exome sequencing analysis revealed AMBRA1 (Autophagy and Beclin 1 Regulator 1) as a novel candidate gene harboring two germline variants: p.Gln30Arg (Q30R) and p.Arg1195Ser (R1195S). AMBRA1 is a key regulator of the autophagy signaling network and a tumor suppressor. To functionally validate the role of AMBRA1 in the clinical manifestations of CS, we generated AMBRA1 depletion and Q30R mutation in hTERT-RPE1 (humanTelomerase Reverse Transcriptase-immortalized Retinal Pigmented Epithelial cells) using the CRISPR-Cas9 gene editing system. We observed that both AMBRA1-depleted and mutant cells showed accumulation in the S phase, leading to hyperproliferation, which is a characteristic of hamartomatous lesions. Specifically, the AMBRA1 Q30R mutation disturbed the G1/S transition of cells, leading to continuous mitotic entry of mutant cells, irrespective of the extracellular condition. From our analysis of primary ciliogenesis in these cells, we speculated that the mitotic entry of AMBRA1 Q30R mutants could be due to non-functional primary cilia that lead to impaired processing of extracellular sensory signals. Additionally, we observed a situs inversus phenotype in ambra1-depleted zebrafish, a developmental abnormality resulting from dysregulated primary ciliogenesis. Taken together, we established that the AMBRA1 Q30R mutation that we observed in CS patients might play an important role in inducing the hyperproliferative potential of cells through regulating primary ciliogenesis.

Breast Hamartoma: Clinical, Radiological, and Histopathological Evaluation

Objective

Breast hamartomas are rare, benign, and slow-growing breast tumors that can be definitively diagnosed by combining the results of clinical, radiological, and histopathological examination. This study aimed to evaluate the clinical, radiological, and histopathological features of hamartomas and summarize our clinical approach to hamartomas.

Materials and Methods

Patients diagnosed with breast hamartoma between 2010 and 2020 in our clinic were retrospectively analyzed. Demographic information, clinical examination, radiological findings, histopathological features, changes during follow-up, and follow-up data were obtained and analyzed.

Results

Of the 1,429 patients operated on in our clinic for benign breast diseases between January 2010 and March 2020, 39 (2.7%) were diagnosed with breast hamartomas with histopathological examination. All patients were women with a median age of 37 (19-62) years. Most of the patients (64%) were in the premenopausal period. Radiological examinations were conducted using mammography (66%), breast ultrasonography (100%), and breast magnetic resonance imaging (48%). Biopsy was performed in 14 preoperative patients, and nine (64%) patients were diagnosed with hamartoma. All patients were operated on; 37 patients underwent a lumpectomy, and two had a mastectomy. No patients had hamartoma recurrence during an average follow-up period of 39 months.

Conclusion

Hamartomas are similar to other benign breast pathologies. Definitive diagnosis can be achieved by combining the results of clinical, radiological, and histopathological examination. Given its similar composition to normal breast tissue, hamartoma has a low rate of malignancy. Definitive diagnosis and appropriate surgical treatment are required.

Breast hamartoma: reassessment of an underrecognized breast lesion

AIMS

Breast hamartomas are an under-recognized lesion because they lack a distinctive microscopic appearance. Microscopic diagnosis can often conclude "no significant lesion" or "normal breast tissue", leading to repeated biopsies and diagnostic delay. We describe the histological, immunohistochemical and radiological features of breast hamartomas in the aim of identifying specific signs to facilitate their diagnosis and to differentiate them from normal breast and fibroepithelial lesions. METHODS AND RESULTS: Forty-seven breast hamartomas were reassessed (histological diagnosis and imaging features). An immunohistochemical study (ER, PR, CD34, HMGA2) was performed. On breast imaging, hamartomas most often presented as probably benign solid masses with circumscribed margins and variable densities. Histologically, breast hamartomas resembled normal breast, although their stromal component was predominant, separating randomly scattered epithelial elements, with areas of pure collagenous stroma. Pseudo angiomatous stromal hyperplasia (PASH) was present in 93.6% of cases and CD34 antibody highlighted intralobular, perilobular and interlobular distribution of CD34-positive fibroblasts. By comparison, CD34 was mostly expressed in the intralobular normal breast tissue stroma. Hamartoma stromal cells expressed HMGA2, ER and PR in 79%, 66% and 76.3% of our cases, respectively, compared to 7.7%, 23% and 19% in normal breast tissue, respectively (P<0.0001; P=0.0005; P<0.0001).

CONCLUSIONS

After ascertaining that core needle biopsy is effectively intralesional, breast hamartomas can be diagnosed with confidence by taking into account the presence of stromal changes, PASH, interlobular distribution of CD34-positive fibroblasts, HMGA2 and hormonal receptor stromal expression.

Malignant phyllodes tumor with extensive lipomatous differentiation

Phyllodes tumors are uncommon neoplasms of the breast. Lipomatous differentiation of malignant phyllodes tumor is a rare stromal alteration of this fibroepithelial tumor, demonstrated as a fat-containing mass on imaging. We present the case of a 46-year-old woman who was diagnosed with a malignant phyllodes tumor of the breast that demonstrated extensive lipomatous differentiation.

Mammary hamartoma: is ultrasound-guided vacuum-assisted breast biopsy sufficient for its treatment?

Background

Mammary hamartomas were mostly benign tumors with rare rate of recurrence and malignant transformation. Ultrasound (US)-guided vacuum-assisted breast biopsy (VABB) has been reported sufficiently safe in treating many breast benign tumors but remained undefined in mammary hamartoma for its usual underdiagnosis in US. Thus, this study aims to evaluate the efficiency of US-guided VABB in treating mammary hamartomas.

Methods

From May 2015 to March 2019, 3,388 lesions of 2,534 patients underwent percutaneous US-guided VABB, among which 31 mammary hamartomas proved by pathology were included in this study. Patients were followed up by US three, six and twelve months later, then at 1-year intervals. Lesions were classified to analyze the possible factors associated with excision rate, bleeding volume and complications.

Results

Of the 31 patients, recurrence was seen in 1 case in 1 year after the procedure and complete excision rate was 96.8% (30/31). The bleeding volume ranged from 1 to 15 mL (mean number ± standard deviation, 6.5±3.4 mL) and significant statistical differences were detected in patient age and the largest diameter of lesions. The main complications included pain (22.6%), hematomas (9.7%) and ecchymosis (3.2%).

Conclusions

US-guided VABB ensures an outstanding complete excision rate and provides an alternative solution to treat mammary hamartomas.

A Male Patient With Breast Hamartoma: An Uncommon Finding

Mammary hamartoma is a rare type of breast tumor that is composed of the same elements as normal mammary tissue. This condition is very rare in men. In current literature, there are fewer than five case reports on male breast hamartoma. This benign pathology is under-reported because of several reasons. Since breast tumors are still considered an exclusively female diagnosis and statistically proven to be gynecomastia when arising in men, they are often overlooked. In addition to the uncommon clinical presentation in men, insufficiency of definitive pathologic and radiologic characteristics can make an accurate diagnosis a challenging task. Mammary hamartoma is a benign condition with an excellent prognosis. The following case describes a rare instance of an enlarging mammary hamartoma in a male patient, highlighting the imaging features, pathohistological findings, and clinical management.

What you see is not always what you get: Radiographic-pathologic discordance among benign breast masses

The differential diagnosis for benign breast masses is broad and ranges from common lesions like fibroadenomas to rare masses like breast hamartomas. Fibroadenomas are proliferative benign masses made up of fibroglandular tissue. Hamartomas are neoplasms comprised of different tissues that are endogenous to the area where they originate. Breast hamartomas specifically, are rare, benign slow growing tumours comprised of fibrotic stroma, adipose, glandular tissue, and epithelial components. Both lesions are painless, firm, and are typically palpable on clinical exam. Given their similarities in composition, diagnosing these masses can be challenging, but may be confirmed with ultrasonography, mammogram, computed tomography, magnetic resonance imaging, or via histological specimen. Once diagnosed, surgical excision is the preferred treatment option. We present a 33-year-old woman with a large left breast mass that gradually increased in size and provide a review of the current literature regarding the challenge of distinguishing between breast fibroadenomas and hamartomas.

Core needle biopsy of benign, borderline and in-situ problematic lesions of the breast: Diagnosis, differential diagnosis and immunohistochemistry

Core needle biopsy (CNB) is the most common sampling technique for the histologic evaluation of breast abnormalities. Diagnosing benign proliferative, borderline and some in-situ lesions in CNB is challenging and subject to a significant degree of interobserver variability. In addition, due to the inherent limitations of CNB, "upgrading" to a more significant pathology at excision is an important consideration for some lesions. Pathologists carry a major responsibility in patient diagnosis, risk stratification and management. Familiarity with the histologic features and the clinical significance of these common and problematic lesions encountered in CNB is necessary for adequate treatment and patient follow-up. This review will focus on benign, atypical and in-situ epithelial proliferations, papillary lesions, radial sclerosing lesions, adenosis and cellular fibroepithelial lesions. Highlights of histologic features, useful strategies for accurate diagnosis, basic immunohistochemistry and management will be presented.

Mammary myoid hamartomas: reports of two cases and a review of the literature

The purpose of this report is to determine the clinicopathological and immuno-phenotypical characteristics of myoid hamartoma of the breast (MHB). The clinical data, histological morphology, and immunohistochemical results of 2 patients diagnosed with MHB were analyzed, and 15 cases of MHB reported in China were reviewed. Both patients were female, aged 28 and 35 years old, and their lesions were located in the upper outer quadrant of the left breast and the right breast respectively. The lesions measured 3 cm × 3 cm × 2.5 cm and 6.5 cm × 6 cm × 4.5 cm. A gross examination indicated a grayish solid block with clear boundaries. A microscopic examination showed different proportions of ducts and acini, beam myoid cells, adipose tissue, and fibrous stroma. The myoid cell bundles of both specimens were positive for vimentin, SMA, h-caldesmon and desmin, but negative for ER, PR, PCK, s-100, Calponin, and P63. Both cases were confirmed as MHB based on their clinical, histological and immuno-phenotypical characteristics. Our findings provide further insights into the pathological basis of MHB, which can help avoid both misdiagnosis and missed diagnosis.

Our 20-Year Institutional Experience with Surgical Approach for Breast Hamartomas

Objective

Hamartomas are rare, slowly-growing breast tumours. Clinical, radiological and histopathological examination together increase the diagnostic accuracy. To evaluate the clinicopathologic features of hamartomas and outline our clinical approach to hamartomas in our 20-year experience at our Breast Clinic.

Materials and Methods

Between 1995 and 2015, 24 cases were retrospectively analyzed with a diagnosis of breast hamartoma at our Breast Clinic followed by excisional biopsy. Data was obtained on patient demographics, clinical examination, radiological findings and histopathological subtypes.

Results

Of 1338 benign breast tumours excised from January 1995 to January 2015, 24 (1.8%) were identified as breast hamartoma. Median age of patients was 42 (range, 13-70), whereas the median tumour size was 5 cm (1-10 cm). On preoperative imaging, hamartoma was most commonly misdiagnosed as fibroadenoma. Pathological examination of the 24 biopsy specimens revealed 3 cases with pseudoangiomatous stromal hyperplasia, and another hamartoma associated with a radial scar within the centre of the lesion. Of those, one patient was diagnosed with malignant phylloides tumour in the same breast. At a median follow-up 58.4 months, none of the patients recurred or developed malignancy.

Conclusion

Hamartomas can often be missed by clinicians, due to its benign nature which is poorly understood. Despite their slow growth, hamartomas can reach large sizes and can cause breast asymmetry. Although it is rare, hamartoma can be seen along with malignancy, as it is formed from similar components of breast tissue. Therefore, careful diagnosis and appropriate management including surgery are required.

Benign Breast Tumours - Diagnosis and Management

With improvements in breast imaging, mammography, ultrasound and minimally invasive interventions, the detection of early breast cancer, non-invasive cancers, lesions of uncertain malignant potential, and benign lesions has increased. However, with the improved diagnostic capabilities comes a substantial risk of false-positive benign lesions and vice versa false-negative malignant lesions. A statement is provided on the manifestation, imaging, and diagnostic verification of isolated benign breast tumours that have a frequent manifestation, in addition to general therapy management recommendations. Histological evaluation of benign breast tumours is the most reliable diagnostic method. According to the S3 guideline and information gained from analysis of the literature, preference is to be given to core biopsy for each type of tumour as the preferred diagnostic method. An indication for open biopsy is also to be established should the tumour increase in size in the follow-up interval, after recurring discrepancies in the vacuum biopsy results, or at the request of the patient. As an alternative, minimally invasive procedures such as therapeutic vacuum biopsy, cryoablation or high-intensity focused ultrasound are also becoming possible alternatives in definitive surgical management. The newer minimally invasive methods show an adequate degree of accuracy and hardly any restrictions in terms of post-interventional cosmetics so that current requirements of extensive breast imaging can be thoroughly met.

Developmental disorders and malformations of the breast

Developmental abnormalities and malformations of the breast are rare and encompass a variety of genetic, syndromic, acquired and sporadic conditions. Abnormalities in development may include irregularities in the nipple areolar complex and/or the underlying glandular tissue, resulting in under or overdevelopment of breasts. Age of presentation and clinical severity is dependent on the underlying biologic cause. Abnormalities may involve the entirety of unilateral or bilateral breasts, particularly in association with syndromic conditions or endocrine abnormalities. Disordered development may also be focal, resulting in tumor-like lesions such as hamartomas, pseudoangiomatous stromal hyperplasia and gynecomastia. In this review, we discuss the disorders of breast development including etiologies, clinical presentations and corresponding histopathologic features.

Giant left breast hamartoma in a 45-year-old woman

This is a case of a woman in her fifth decade of life who presented with a lump in her left breast. The patient underwent extensive breast investigations which did not confirm one particular diagnosis. The lesion was excised, and histological findings confirmed the diagnosis of a giant breast hamartoma. This case is interesting due to the largeness. As well as this, giant breast hamartomas are uncommon, and this case highlights the difficulty in their diagnosis and frequent misdiagnoses, potentially contributing to their reported low incidence rates. Diagnosis is difficult due to the complex appearance of the mass on imaging, raising the possibility of malignancy. Core biopsy is unremarkable, with the final diagnosis only possible on histological examination of the resected mass.

Ductal Carcinoma in situ of the breast in sclerosing adenosis encapsulated by a hamartoma: A case report

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Ductal Carcinoma in situ in sclerosing adenosis encapsulated by a hamartoma is rare.

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The diagnosis is difficult due to the appearance of these combined lesions.

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Atypical appearance of a hamartoma may suggest a co-existing malignancy.

Introduction

Ductal Carcinoma in situ (DCIS) of the breast can develop in areas of sclerosing adenosis. The radiographic finding of sclerosing adenosis is a spiculated mass and can look like invasive ductal carcinoma. We report a patient with DCIS in sclerosing adenosis encapsulated by a hamartoma, with imaging findings quite different from the typical findings of sclerosing adenosis.

Presentation of case

A 73-year old woman, with no previous mammography, presented with a palpable mass in the left breast. Mammography showed a 36 mm well-defined mass with fat density in the middle outer quadrant of the left breast. Ultrasonography showed a well-defined mass in the same area which was composed of hypoechoic and hyperechoic areas. The histological diagnosis by core needle biopsy was sclerosing adenosis. We considered the patient’s age and tumor size and performed a partial mastectomy for both diagnosis and treatment. Final pathology showed DCIS in sclerosing adenosis in a hamartoma.

Discussion

This patient had DCIS in an area of sclerosing adenosis, encapsulated by a hamartoma. DCIS can develop in areas of sclerosing adenosis, and can appear similar to invasive ductal carcinoma, so we must avoid misdiagnosis or over-treatment. Malignant transformation of a hamartoma is rare, but can occur since it contains epithelial tissue. Definitive biopsy should be performed due to the possibility of a malignancy inside the hamartoma.

Conclusions

When diagnosing a hamartoma, the presence of atypical findings on imaging studies, should suggest the possibility of malignancy. Although rare, a malignant tumor may be present inside the hamartoma.

Hamartoma of the Breast: An Underrecognized Disease?

Hamartomas of the breast are benign tumors composed primarily of dense, fibrous tissue with variable amounts of fat and associated ducts.

A 48-year-old woman had noted a lump in her right breast for a number of years. She came to our clinics because of the recent progressive enlargement of this lump. Physical examination revealed a large, mobile, round, painless mass in the lower inner quadrant of the right breast. There were no palpable axillary lymph nodes. Mammography showed a circumscribed, 4.5 × 2.5 cm mass with a radiolucent periphery and moderately radiopaque center. On the basis of the clinical and mammographic findings, hamartoma of the breast was highly suspected. A lumpectomy was performed and histological examination of the specimen revealed overgrowth of mammary lobules and ductules, forming a well-circumscribed lesion with admixed fat tissue. Hamartoma of the breast was confirmed.

With the awareness of this entity and good correlation of imaging findings, the clinical diagnosis of hamartoma of the breast should not be difficult. If careful attention is paid to the clinical information, histological underdiagnosis of hamartoma of the breast can be avoided.

Benign Breast Diseases: Evaluation and Management

Benign breast disease is a spectrum of common disorders. The majority of patients with a clinical breast lesion will have benign process. Management involves symptom control when present, pathologic-based and imaging-based evaluation to distinguish from a malignant process, and counseling for patients that have an increased breast cancer risk due to the benign disorder.

Lipomatous tumors of the breast: A contemporary review

Breast tumors with lipomatous or liposarcomatous components are infrequently encountered, but can be a source of diagnostic difficulty if the context of the fatty differentiation is not recognized. Among the true adipocytic tumors, lipoma is the most common lipomatous tumor arising in the breast. Several mammary spindle cell tumors may show adipocytic differentiation, including fibroepithelial tumors and myofibroblastoma. Liposarcomatous components most often arise in malignant phyllodes tumors, as opposed to primary liposarcomas of the breast which are believed to be uncommon. This article will review the spectrum fat-containing tumors of the breast with an emphasis on differential diagnosis and insights from recent molecular studies.

The First Case of HER2+ Invasive Ductal Carcinoma Arising From a Breast Hamartoma and Literature Review

Carcinomas arising from breast hamartomas are exceedingly rare. We present the first reported case of an African-American female presenting with a right breast lump and a subsequent mammogram suggestive of a hamartoma. She later underwent lumpectomy and was found to have HER2+ invasive ductal carcinoma (IDC) arising from a hamartoma. She was amenable to HER2-targeted trastuzumab, hormone therapy and adjuvant radiation but declined chemotherapy. In a review of the literature, IDC is the predominant neoplastic type found in hamartomas. The average hamartoma size at time of neoplasm diagnosis is 6.0 cm. Patients with hamartomas greater than 6.0 cm, with changes in calcification pattern; new nodules or asymmetry should be considered for additional evaluation with ultrasound, MRI and/or biopsy. HER2 status is under-reported among cases and should be evaluated in any malignancy found within hamartomas as HER-2 therapy has improved overall survival and recurrence free survival in HER2+breast cancer patients.

Fibroepithelial Lesions in the Breast of Adolescent Females: A Clinicopathological Study of 54 Cases

Fibroepithelial lesions (FELs) are the most frequent breast tumors in adolescent females. The pubertal hormonal surge could impact the growth and microscopic appearance of FELs in this age group. In this study, we evaluate the morphology and clinical behavior of FELs in adolescents. We searched the 1992-2012 pathology data base for FELs in females 18 years old or younger (F ≤18 years). Seven FELs from 1975 to 1983 were also included. Three pathologists reviewed all available material. Patient (pt) characteristics and follow-up information were obtained from electronic medical records. Forty-eight F ≤18 years had 54 FELs with available slides. Thirty (67%) pts were Caucasian, 12 (27%) African-American, two (4%) Hispanic, one (2%) Asian; three were of unknown race/ethnicity. Median age at diagnosis was 16 years. Median age at menarche was 12 years; most (96%) FELs occurred after menarche (median interval 48 months). All patients underwent lumpectomy; one required subsequent mastectomy. The FELs were 34 fibroadenomas (FAs) (11 usual, 23 juvenile), and 20 phyllodes tumors (PTs) (16 benign, one borderline and three malignant). Eight (35%) juvenile FAs showed slight intratumoral heterogeneity. The mean mitotic rate was 1.3 mitoses/10 high-power fields (HPFs) (range, 0-6) in usual FAs, 1.8/10 HPFs in juvenile FAs, 3.1/10 HPFs in benign PTs, 10/10 HPFs in the borderline PT and 17/10 HPFs in malignant PTs. The mean follow-up for 29 pts with 33 FELs was 44 months. Two (10%) PTs recurred locally (a benign PT at 18 months, and a borderline PT at 11 months). Both recurrent PTs had microscopic margins <1 mm. Mitotic activity in FAs from adolescents can be substantial and this finding should be interpreted cautiously. Awareness of the morphologic features of FELs in adolescents is important to avoid overdiagnosis of PTs, which can lead to additional unnecessary and potentially disfiguring surgery.

[Rare benign breast tumors including Abrikossoff tumor (granular cell tumor), erosive adenomatosis of the nipple, cytosteatonecrosis, fibromatosis (desmoid tumor), galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma: Guidelines for clinical practice]

OBJECTIVES

To provide guidelines for clinical practice from the French College of Gynaecologists and Obstetricians (CNGOF), based on the best evidence available, concerning rare benign breast tumors: Abrikossoff (granular cell tumor), erosive adenomatosis of the nipple, cytosteatonecrosis, fibromatosis (desmoid tumor), galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma.

METHODS

Bibliographical search in French and English languages by consultation of Pubmed, Cochrane and international databases.

RESULTS

For erosive adenomatosis of the nipple, surgical excision is recommended to exclude Paget's disease or cancer (grade C). When surgery is performed for breast desmoid tumor or syringomatous adenoma, free margins are recommended (grade C). Without clinico-radio-histologic discordance, surgical abstention may be proposed for Abrikossoff tumor (granular cell tumor), cytosteatonecrosis, galactocele, hamartoma, hemangioma, lipoma, juvenile papillomatosis, pseudoangiomatous hyperplasia, and syringomatous adenoma (grade C).

Breast hamartoma: Is this an uncommon or an under-recognised lesion?

A hamartoma is a disorganised focus of a mature overgrowth of cells composed of tissue elements of the organ in which it is found, and it can occur anywhere in the body. A breast hamartoma is a rare, benign tumour consisting of fat, glandular and fibrous tissue, and is known by various names such as lipofibroadenoma or fibroadenolipoma, depending on the dominant tissue found within the lesion. The reported incidence is low (0.1% – 0.7%), but is increasingly thought to be because of under-diagnosis of the condition.

Myoid hamartoma of the breast with focal chondromyoxid metaplasia and pseudoangiomatous stromal hyperplasia: A case report

Hamartomas of the breast, also known as fibroadenolipomas, lipofibroadenomas or adenolipomas, are benign lesions. Hamartomas account for between 0.04 and 1.15% of all benign breast tumors in females. Myoid hamartoma of the breast (MHB) is extremely rare. The present study describes a case of MHB in a 44-year-old female. Screening mammography revealed a lobulated partial indistinct isodense mass measuring ~3.8 cm in the upper outer quadrant of the left breast. Sonographic examinations revealed a 2–3-cm mass in the left breast, which was fairly well circumbscribed and demonstrated complex scattered echogenic areas and isoechoic tissue. A core needle biopsy demonstrated fibrocystic changes, with small focal ductule aggregations. As malignancy could not be excluded, a partial mastectomy was performed using a circumareolar incision. The mass was histopathologically diagnosed as MHB with focal chondromyoxid metaplasia and pseudoangiomatous stromal hyperplasia. The histological diagnosis was based upon the findings of the well-circumscribed tumor, which was composed of entrapped mammary ducts, fat cells and myoid stromal components, with focal chondromyxoid metaplasia and pseudoangiomatous stromal hyperplasia. The tumor cells exhibited diffuse cluster of differentiation 34-positive immunoreactivity, which was consistent with a diagnosis of pseudoangiomatous stromal hyperplasia.

Breast hamartoma: a clinicopathologic analysis of 27 cases and a literature review

OBJECTIVES

Breast hamartoma is an uncommon breast tumor that accounts for approximately 4.8% of all benign breast masses. The pathogenesis is still poorly understood and breast hamartoma is not a well-known disorder, so its diagnosis is underestimated by clinicians and pathologists. This study was designed to present our experience with breast hamartoma, along with a literature review.

METHOD

We reviewed the demographic data, pathologic analyses and imaging and results of patients diagnosed with breast hamartoma between December 2003 and September 2013.

RESULTS

In total, 27 cases of breast hamartoma operated in the Ankara University Medicine Faculty's Department of General Surgery were included in the study. All patients were female and the mean age was 41.8±10.8 years. The mean tumor size was 3.9±2.7 cm. Breast ultrasound was performed on all patients before surgery. The most common additional lesion was epithelial hyperplasia (22.2%). Furthermore, lobular carcinoma in situ was identified in one case and invasive ductal carcinoma was observed in another case. Immunohistochemical staining revealed myoid hamartoma in one case (3.7%).

CONCLUSION

Breast hamartomas are rare benign lesions that may be underdiagnosed because of the categorization of hamartomas as fibroadenomas by pathologists. Pathologic examinations can show variability from one case to another. Thus, the true incidence may be higher than the literature indicates.

Hamartoma of the breast in a young woman. Case report

Hamartoma is a benign tumor-like malformation characterized by a focal mixture of mature cells and tissues normally present in affected area. The hamartoma of the breast is rare. We report a case in an asymptomatic young woman coming to our attention for a left breast lesion detected by ultrasound screening.

Hyperechoic lesions of the breast: radiologic-histopathologic correlation

OBJECTIVE

Breast ultrasound is helpful in the characterization of masses to differentiate benign from malignant disease. The internal echotexture of a mass is an important ultra-sound feature in breast diagnostic workup. This article reviews the imaging and histopathology findings of benign and malignant hyperechoic masses to better recognize these conditions.

CONCLUSION

Hyperechoic masses are frequently benign, including hematoma, fat necrosis, abscess, and benign neoplasm. Malignant hyperechoic lesions include invasive ductal and invasive lobular carcinoma, lymphoma, and sarcoma. Understanding lesion echotexture in the context of clinical and mammographic findings will help establish appropriate diagnoses for hyperechoic masses.

Rare Benign Entities of the Breast - Myoid Hamartoma and Capillary Hemangioma

Hamartomas can occur in different areas of the breast, but they are rarely found in the breast. Myoid hamartomas with smooth muscle cells of the type described here are particularly unusual. The pathogenesis of this benign entity with its tendency to growth and recurrence is not clear. Excision is the therapy of choice. Capillary hemangiomas are rare vascular malformations of the breast which, in contrast to cavernous hemangiomas, usually remain clinically occult. It is important to differentiate these benign findings from malignant angiosarcoma. The possible heterogeneities between myoid hamartoma and capillary hemangioma using current breast imaging methods for the differential diagnosis (high-resolution ultrasound, duplex sonography, shear wave elastography, digital mammography, minimally invasive intervention) are discussed together with an overview of the literature.

Pseudoangiomatous Stromal Hyperplasia (PASH) of the Breast

Background. Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign lesion that can present as a palpable nodule or as an incidental finding in breast biopsies. Design. The study comprised 79 cases diagnosed at Loyola University Medical Center from 2002 to 2009. The pathology slides were reviewed to document the distribution, type, and association with preneoplastic or neoplastic epithelial lesions. Z-test for independent proportions is used for analysis. Results. A total of 76 patients were female and 3 were male. In all, 59.8% of patients presented with a breast mass and in 40.2% the lesion was an incidental finding. Classical PASH morphology was seen in 97.6% and proliferative PASH in 2.4%. Associated epithelial lesions were benign proliferative changes in 60.4%, atypical ductal and atypical lobular hyperplasia in 25.6% and infiltrating carcinoma in 11% of cases. Conclusions. Based on these results, extensive sampling of biopsy specimen with PASH and appropriate clinical and radiologic follow-up is recommended.

Management of breast magnetic resonance imaging-detected lesions

Breast magnetic resonance imaging (MRI) has become an essential component of breast imaging. Whether it is used as a problem-solving tool or a screening test or for staging patients with breast cancer, it detects many lesions in the breast. The challenge for the radiologist is to distinguish significant from insignificant lesions and to direct their management. A brief summary of the terminology according to the American College of Radiologists lexicon will be provided. This review article will cover the differential diagnosis of enhancing lesions, including masses and nonmass enhancement, from benign and malignant causes. Some of the specific morphologic and kinetic features that help to differentiate benign from malignant lesions will be illustrated, and positive predictive values of these features will be reviewed. The various methods of investigating enhancing lesions of the breast will be discussed, including second-look ultrasound, ultrasound-guided biopsy, stereotactic biopsy, and MRI-guided biopsy. A practical approach to the management of MRI-detected lesions will include timing of follow-up, when to biopsy and when to ignore enhancing lesions in the breast.

Breast MR with special focus on DW-MRI and DCE-MRI

The use of magnetic resonance imaging (MRI) for the assessment of breast lesions was first described in the 1970s; however, its wide application in clinical routine is relatively recent. The basic principles for diagnosis of a breast lesion rely on the evaluation of signal intensity in T2-weighted sequences, on morphologic assessment and on the evaluation of contrast enhancement behaviour. The quantification of dynamic contrast behaviour by dynamic contrast-enhanced (DCE) MRI and evaluation of the diffusivity of water molecules by means of diffusion-weighted MRI (DW-MRI) have shown promise in the work-up of breast lesions. Therefore, breast MRI has gained a role for all indications that could benefit from its high sensitivity, such as detection of multifocal lesions, detection of contralateral carcinoma and in patients with familial disposition. Breast MRI has been shown to have a role in monitoring of neoadjuvant chemotherapy, for the evaluation of therapeutic results during the course of therapy. Breast MRI can improve the determination of the remaining tumour size at the end of therapy in patients with a minor response. DCE-MRI and DW-MRI have shown potential for improving the early assessment of tumour response to therapy and the assessment of residual tumour after the end of therapy. Breast MRI is important in the postoperative work-up of breast cancers. High sensitivity and specificity have been reported for the diagnosis of recurrence; however, pitfalls such as liponecrosis and changes after radiation therapy have to be carefully considered.

Clinician's guide to imaging and pathologic findings in benign breast disease

The discussion of abnormal results of breast imaging and abnormal pathologic findings can be challenging for health care professionals and often is stressful for patients. Although most imaging findings and biopsy results are negative and do not infer a substantial increase in breast cancer risk, the subsequent conversation between the patient and her practitioner is more effective and informative with a thorough review of the pathologic results and an appreciation of the importance of radiologic-histologic concordance. This article provides insight into and understanding of breast imaging and biopsy techniques and of histologic findings as a means to timely and appropriate decision making and action by the patient and her health care professional.

A diagnostic dilemma in breast pathology--benign fibroadenoma with multinucleated stromal giant cells

Fibroadenomas are common benign breast tumours that display a characteristic pathological morphology, although several epithelial and stromal variations exist. A very rare histological finding is the presence of multinucleated giant cells throughout the stroma of a benign fibroadenoma. Cells of this type, which are more commonly found incidentally within the interlobular stroma of breast tissue, are benign and should not be mistaken for malignant cells on microscopic examination. Unfortunately a lack of awareness of this pathological entity can lead to diagnostic confusion amongst pathologists resulting in the multinucleate giant cells being mistaken for highly mitotic cells and consequently the fibroadenoma being mistaken for a malignant lesion. This may have serious implications for the subsequent management of the patient. The presence of this unusual cell type in the stroma does not alter the prognosis of otherwise benign lesion. We encountered two such cases at our institution in a six month period recently. We present their histories along with relevant radiological, microscopic and immunohistochemical features, followed by a discussion of this unusual pathological entity.

Spindle cell lesions of the breast--the pathologic differential diagnosis

Spindle cell lesions of the breast represent an interesting diagnostic problem, as the differential diagnoses are wide. Diagnosing this is particularly problematic but important when encountered in a needle core biopsy, as treatments of different entities are different. In the histologic assessment of spindle cell lesions, the simplified approach is to evaluate the spindle cells and the accompanying epithelial cells. In the biphasic lesions with predominance of spindle cells with benign epithelial component, fibroepithelial lesions including fibroadenomas and phyllodes tumors are the most common, followed by pseudoangiomatous stromal hyperplasia, hamartoma and adenomyoepithelioma. For biphasic lesions with predominance of spindle cells with malignant epithelial component, the biphasic metaplastic carcinoma is likely. For monophasic lesions with pure pleomorphic spindle cell only, the monophasic metaplastic carcinoma is more common than the rare primary sarcomas like malignant fibrous histiocytoma, angiosarcoma, and other high grade sarcomas. In monophasic lesions with pure bland spindle cells only, the possible lesions include fibromatosis, fibromatosis like metaplastic carcinoma and other unusual conditions like dermatofibrosarcoma protuberance. By careful searching for the accompanying epithelial element, and with the aid of appropriate clinical input and judicious use of immunohistochemistry, many of these lesions can be confidently diagnosed in the needle core biopsy, thus facilitating appropriate treatments.

Sonographic features of breast hamartomas

OBJECTIVE

The purpose of this study was to elucidate the sonographic characteristics of breast hamartomas.

METHODS

Data and sonographic images of 14 breast hamartomas were retrospectively reviewed.

RESULTS

All patients had clinically palpable lumps. The median patient age was 39.5 years (range, 24-60 years). Eleven (78.6%) tumors occurred in the right breast, and 3 (21.4%) were in the left. The median tumor size measured by sonography was 2.8 cm (range, 1.2-4.9 cm). The median longest transverse dimension-anteroposterior diameter ratio of the tumors was 2.44 (range, 1.52-3.73). All tumors were oval and compressible with transducer pressure. Thirteen (92.9%) tumors were well circumscribed with smooth tumor margins, and 1 (7.1%) had indistinct margins. The internal echo texture was hyperechoic in 6 (42.9%), mixed (heterogeneous) echogenicity in 5 (35.7%), and isoechoic in 3 (21.4%). Four (28.6%) tumors had echogenic halos, and 2 (14.3%) had anechoic halos. Ten (71.4%) tumors had no retrotumor acoustic phenomena. Two (14.3%) had bilateral edge shadowing; 1 (7.1%) had posterior enhancement; and 1 (7.1%) had a mixture of enhancement and shadowing.

CONCLUSIONS

Breast hamartomas were well-circumscribed, solid, oval tumors without intratumor microcalcification. The internal echo texture of most hamartomas is either hyperechoic or composed of mixed echogenicity. Retrotumor acoustic phenomena were absent in most hamartomas.

Myoid hamartoma of the breast: a case report and review of the literature

Myoid hamartomas of the breast are extremely rare breast lesions, with a poorly understood pathogenesis. A 60-year-old woman presented with a palpable mass in the right breast. Breast ultrasonography and mammography showed the presence of a breast lesion with benign characters, but were not diagnostic. A local excision of the mass was performed; histology revealed that the tumor was composed of epithelial and stromal cells. Histological and immunohistochemical findings established the diagnosis of myoid hamartoma. The patient is well 4 years later without tumor recurrence. Breast myoid hamartomas are exceptionally rare benign lesions; complete surgical excision achieves cure.

Divergences in diagnosing nodular breast lesions of noncarcinomatous nature

Nodular breast lesions of noncarcinomatous origin are often of fibroepithelial origin. They may cause classification problems when they are hypocellular or hypercellular; the latter setting may also raise the differential diagnosis of phyllodes tumors. Thirty equivocal nodular breast lesions were collected and one hematoxylin and eosin slide from each was assessed by six pathologists with special interest in breast pathology. The overall reproducibility of classifying these lesions into categories of fibroadenoma, phyllodes tumor or anything else was moderate (kappa value: 0.48). The lack of a uniform nomenclature was not felt disturbing for hypocellular lesions, but the discordant diagnosis of tumors resembling or representing phyllodes tumors was acknowledged to require intervention, such as more obvious implication of guidelines and quality assurance programs aiming at assessing diagnoses and prognostic parameters.

Myoid hamartoma of the breast: case report and review of the literature

Hamartoma is a mass of disorganized but mature specialized cells or tissue indigenous to the particular site. They can occur anywhere in the body, and their common sites of occurrence include lungs, skin, hypothalamus, spleen, and kidneys, of which lungs are the most common. We report a rather unusual, largely unrecognized case of myoid hamartoma of the breast. They constitute approximately 3.9%-4.8% of breast tumors. Myoid hamartomas belong to a spectrum of benign breast lesion of dual origin, containing myoepithelial and myofibroblastic components in varying proportions. They are usually asymptomatic but can present as well-circumscribed masses that do not possess specific diagnostic histologic features, and diagnosis is, therefore, difficult. In contrast to many other benign or malignant breast lesions, the diagnosis of hamartoma can easily be missed. Herein, we discuss the importance of radiologic, immunohistochemical studies and histopathologic findings in the diagnosis of a myoid hamartoma. Extensive review of the literature has been done for this purpose, and we highlight the clinical presentation and therapeutic aspects of this breast lesion.

Benign breast diseases: classification, diagnosis, and management

Benign breast diseases constitute a heterogeneous group of lesions including developmental abnormalities, inflammatory lesions, epithelial and stromal proliferations, and neoplasms. In this review, common benign lesions are summarized and their relationship to the development of subsequent breast cancer is emphasized.

Infiltrating ductal carcinoma and ductal carcinoma in situ associated with mammary hamartoma

Mammary hamartoma is a rare nonmalignant lesion. Only 11 cases of carcinoma associated with hamartoma have been previously described in the literature. We describe a case of infiltrating ductal carcinoma (IDC) and ductal carcinoma in situ (DCIS) associated with hamartoma in a 35-year-old woman. Mammography showed the features of a typical hamartoma with suspicious microcalcifications arising in it. The patient underwent a radical modified mastectomy. It is likely that hamartoma is a coincidental finding. The identification of suspicious microcalcifications in a typical mammographic image of a hamartoma should prompt continued examination to exclude an underlying tumor.

Rapidly growing nodular pseudoangiomatous stromal hyperplasia of the breast in an 18-year-old girl. Case report

Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a rare benign proliferation of mesenchymal stromal cells with irregular slit-like formations resembling angiomatous structures. In the majority of cases this lesion is a focal microscopic finding in breast biopsies performed for benign or malignant diseases. It may present in a pure diffuse or nodular form. The exact etiology and pathogenesis of this tumor-like lesion is still unknown, but a proliferative response of myofibroblasts to hormonal stimuli has been postulated. A large 12 x 9 x 3.5 cm rapidly growing nodular form of PASH of the breast in an 18-year-old woman is here described with clinical and histological findings. A possible hormonal etiology was indicated by elevated progesterone (three-fold) and decreased estrogen serum levels. Different diagnostic lesions, such as giant fibroadenoma and low-grade angiosarcoma, are discussed. To the authors' knowledge this is only the fourth case of nodular PASH of the breast reported in the English literature.