Metastases to the breast

Bladder Cancer Metastasis to the Breast in a Male Patient: Imaging Findings on Mammography and Ultrasonography

Male breast cancer is rare, accounting for approximately 1% of breast cancers. Metastasis from extra-mammary malignancy to the breast in men is extremely rare. The most common primary tumors that metastasize to the breast in male are prostate, lung, stomach, colorectal cancer, melanoma, and sarcoma. To our knowledge, only a few cases of bladder cancer presenting with metastasis to the male breast have been reported, and metastasis with infiltration rather than mass is extremely rare. We report imaging findings on mammography and ultrasonography in a 59-year-old male with bladder cancer metastatic to the breast.

Metastatic non-Hematopoietic Neoplasms to the Breast: A Study of 238 Cases

AIMS

The aim of this study was to review the clinicopathologic characteristics of metastatic non-hematopoietic malignancies to the breast, in order to identify salient features for practicing pathologist that are useful in distinguishing metastatic lesions from primary breast neoplasms.

METHODS AND RESULTS

A total of 238 cases were identified during the period from January 2005 to January 2015. Clinicopathologic features of these cases were retrospectively reviewed. Primary tumors included melanoma (99, 42%), serous carcinoma (35, 15%), neuroendocrine neoplasm (32, 13%), sarcoma (23, 10%), and adenocarcinoma from various organs (47, 20%), among others. Most metastases were unilateral (223, 94%) and unifocal (206, 87%), and were detected radiographically (167, 70%). Concurrent ipsilateral axillary metastasis occurred in 33 (14%) patients. Among 238 cases, 41 had metastatic disease to the breast concurrently or preceding the primary cancer diagnosis. Notable, in 39 (16%) cases, breast metastasis was the first clinical presentation of disease, and 16 (41%) of these cases were initially misdiagnosed as breast primaries. In contrast, with known history of non-mammary primary tumors, only 4 of 197 (2%) cases were misdiagnosed (p<0.0001).

CONCLUSIONS

Metastatic tumors share many overlapping features with breast primary carcinomas. However, cases with a well-circumscribed tumor, lack of in situ component, ER/PR negativity, and unusual morphologic features should raise the consideration of metastatic disease. While clinical history is paramount for correct diagnosis, metastasis to the breast as the first clinical presentation is not uncommon.

High-Grade Spindle Cell Lesions of the Breast: Key Pathologic and Clinical Updates

Most of the high-grade spindle cell lesions of the breast are malignant phyllodes tumors (MPTs), spindle cell carcinomas (SpCCs), and matrix-producing metaplastic breast carcinomas (MP-MBCs). MPTs have neoplastic spindle stromal cells and a classic leaf-like architecture with subepithelial stromal condensation. MPTs are often positive for CD34, CD117, and bcl-2 and are associated with MED12, TERT, and RARA mutations. SpCCs and MP-MBCs are high-grade metaplastic carcinomas, whereas neoplastic epithelial cells become spindled or show heterologous mesenchymal differentiation, respectively. The expression of epithelial markers must be evaluated to make a diagnosis. SAS, or rare metastatic spindle cell tumors, are seen in the breast, and clinical history is the best supporting evidence. Surgical resection is the standard of care.

Metastasis to Breast from Extramammary Solid Tumors and Lymphomas: A 20-Year Population-Based Study

To discuss the clinicopathological features and prognosis of metastases to the breast from extramammary solid tumors and lymphomas, we reviewed Cancer Hospital of Chinese Academy of Medical Sciences database from 01/01/2000 to 12/31/2020. Fifty-nine patients were identified. The most common primary sites for breast metastases were lymph node and pulmonary, followed by nasal cavity, ovary, skin, etc. All the patients were treated with chemotherapy, 18 were operated, 14 accepted radiotherapy. Metastasis to breast should be considered in any patient with tumor history presenting a breast lump. Pathological with immunohistochemical examination should be performed to identify the original site.

Breast metastasis from medullary thyroid carcinoma: a report of a case

Background

Metastasis to the breast is rare. We herein report a patient with metastatic medullary thyroid carcinoma to the breast for whom measuring the calcitonin level was an important clue to the correct diagnosis.

Case presentation

A 54-year-old woman visited our hospital for the treatment of recurrent metastatic medullary thyroid carcinoma due to multiple endocrine neoplasia 2A and breast cancer. Positron emission tomography performed before the operation for metastatic medullary thyroid carcinoma recurrence in the neck showed the accumulation of ¹⁸F-fluorodeoxyglucose in the bilateral breast at sites other than the disease in the neck. Ultrasonography revealed multiple tumors in both breasts. A core needle biopsy of three breast tumors was performed. Microscopically, the tumor cells showed solid growth and did not show a tubular structure. She was diagnosed with triple-negative invasive ductal carcinoma. Post-operative positron emission tomography was performed as the serum calcitonin level increased after the operation. The accumulation of ¹⁸F-fluorodeoxyglucose in the bilateral breast tumors and lymph nodes in the neck was noted. The possibility of the breast tumors being metastasis of metastatic medullary thyroid carcinoma was considered. Needle aspiration was performed for three breast tumors. The calcitonin level of the washout fluid was measured and found to be ≥ 17,500 pg/mL. Immunohistochemistry showed that the tumor cells were calcitonin-positive and gross cystic disease fluid protein-15-negative. Vandetanib was started as recurrent metastatic medullary thyroid carcinoma with breast metastasis was finally diagnosed. The serum calcitonin level decreased after 1 month.

Conclusion

Although breast metastasis of medullary thyroid carcinoma is rare, a correct diagnosis is indispensable for appropriate treatment. When a breast tumor shows atypical morphological features for breast cancer according to the histopathology in a patient with a history of cancer, metastasis to the breast should be considered. Calcitonin measurement of the needle washout fluid was useful for confirming metastatic medullary thyroid carcinoma.

Histological clues to the diagnosis of metastasis to the breast from extramammary malignancies

AIMS

The aims of this study were to review the histological features useful for the identification of metastases to the breast and to investigate the impression that this diagnosis has become more common.

METHODS AND RESULTS

The histological features of metastases to the breast from 2008 to 2018 were reviewed. Seventy-four biopsies from 66 patients were identified: 1% compared with primary carcinoma of the breast. Non-haematological metastases comprised 0.75% compared with 0.3% in a series from 1996 to 2005. The most common tumour types were pulmonary carcinoma (22), lymphoma (15), melanoma (13), gastrointestinal carcinoma (eight) and serous papillary carcinoma (four). In 73% there were histological features that were not typical of primary mammary carcinoma. Some metastases were histologically similar to breast cancer and the history was essential to making the correct diagnosis. Useful histological clues included small-cell morphology for pulmonary carcinoma, glands containing necrosis for gastrointestinal carcinoma, intranuclear inclusions, marked pleomorphism and spindle cells for melanoma, clear cells for renal carcinoma, papillary architecture for serous papillary carcinoma and sheets of centroblasts or nodules of centroblasts and centrocytes for lymphoma. Useful immunohistochemical markers included TTF-1 for pulmonary carcinoma, S100, melan-A and HMB45 for melanoma, CK20 and CDX2 for colorectal carcinoma, PAX8 and WT1 for serous papillary carcinoma and lymphoid markers for lymphomas, in addition to the absence of expression of mammary markers ER, GATA3 and GCDFP-15.

CONCLUSION

The majority of metastases to the breast have histological clues to the diagnosis. Immunohistochemistry is helpful. This diagnosis is being made more frequently.

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.

Concurrent BRAF and PTEN mutations in melanoma of unknown origin presenting as a breast mass

BACKGROUND

Metastases represent a small percentage of the malignancies affecting the breast, and only 5% of melanomas originate from non-cutaneous sites. Multiple genetic aberrations have been associated with the development of melanocytic lesions, including BRAF V600E mutation. Mutations in PTEN gene have also been related to the pathogenesis of multiple malignancies.

PURPOSE/METHOD

This is the case of a 28-year-old female who presented with a tender, palpable mass in the upper outer quadrant of the right breast. Ultrasound showed a 1-cm solid mass, initially diagnosed as invasive ductal carcinoma on biopsy. During pre-operative workup, a second mass was identified and biopsied. Immunohistochemical stains performed on the second mass biopsy demonstrated that the neoplastic cells were positive for cytokeratin AE1/3, pan-melanoma, tyrosinase, and SOX-10 and negative for CK7, CAM5.2, and GATA-3. Subsequent workup showed widespread metastatic disease involving the liver, lungs, bones, and brain. The brain metastasis tested positive for BRAF p.V600E and PTEN p.R130Efs*4 mutations. Thorough skin and eye examination did not reveal a primary melanoma.

CONCLUSION

Only few reports have been published of melanoma presenting as a breast mass. This is an interesting case due to the clinical presentation, diagnostic challenges, and genetic mutations profile.

Metastatic gastric carcinoma to the breast: A case report and review of the Chinese literature

Breast metastasis is extremely unusual in gastric cancer patients worldwide. We herein report the case of a 39-year-old female Chinese patient presenting with symptoms of inflammation in the left breast. A biopsy did not reveal any evidence of malignancy. A modified radical mastectomy was performed and the postoperative pathological examination revealed infiltration by signet ring cell gastric carcinoma. A review of the Chinese literature was performed, and a total of 16 patients with breast metastasis from gastric carcinoma have been reported from 1990 onwards. This condition is associated with a poor prognosis, with a survival time of 1 month to 4 years. More studies are required to determine the optimal treatment.

Primary oral malignant melanoma metastasis to the brain and breast: A case report and literature review

Primary oral malignant melanoma is a rare tumor, which is estimated to comprise 0.2–8.0% of all melanoma cases. This type of cancer is fairly uncommon, its prognosis is dismal, and it frequently exhibits a biologically aggressive behavior. The common location of primary oral malignant melanoma is the hard palate and maxillary alveolus. In ~85% of cases, the melanoma will metastasize to the liver, lung, bone and brain early in the course of the disease. The present study reports the case of a 50-year-old premenopausal woman who presented with primary oral malignant spindle cell melanoma (T3bN2aM0) and underwent complete surgical resection followed by an adjuvant course of radiation therapy. After 1 year, the patient presented with sudden onset slurred speech, and upon examination, was found to have left-sided hemiparesis and a hard left breast mass. Workup confirmed breast and brain metastasis. The patient developed lung metastasis 4 weeks later and was referred for palliative care.

Fine-needle aspiration of metastatic melanoma presenting as bilateral breast cysts

Melanoma is the second most common non-hematopoietic malignancy after carcinomas to metastasize to the breast and often appears as a well-circumscribed, dense nodule on imaging. Although metastatic lesions presenting as bilateral cysts have been reported, this presentation is not common and may mimic benign breast cysts. We present a challenging case of metastatic melanoma presenting as bilateral breast cysts with spindled cytomorphology in a patient with a history of mammary carcinoma. Discordance between the spindled cytomorphology and the morphology of the core biopsy, which was similar to the patient's primary breast cancer, allowed for entertainment of other tumors and disease processes. Confirmatory immunostaining of the cytology material with HMB-45 was important to establish the diagnosis of metastatic melanoma. Diagn. Cytopathol. 2017;45:446-451. © 2017 Wiley Periodicals, Inc.

'Inflammatory breast cancer' due to metastatic adenocarcinoma of lung

A 67-year-old woman with a history of lung adenocarcinoma presented with 3 weeks of redness, pain, swelling and skin changes in her right breast. Her vital signs and physical examination were within physiological limits except for the right breast. She had extensive red streaks radiating from the right nipple with peau d'orange appearance of her overlying skin. Her breast was tender on examination and did not have any associated cervical or axillary lymphadenopathy. Her mammography revealed thickening of the skin, increased parenchymal markings and shrinkage the breast. Multiple skin biopsies demonstrated moderately differentiated lung adenocarcinoma with lymphovascular invasion. The patient made an informed decision to undergo radiotherapy following discussion with her oncologist and breast surgeon. She succumbed to her illness 2 months after the diagnosis of metastasis to her breast.

Metastatic Breast Carcinoma to the Prostate Gland

Cancer of the male breast is an uncommon event with metastases to the breast occurring even less frequently. Prostate carcinoma has been reported as the most frequent primary to metastasize to the breast; however, the reverse has not been previously reported. Herein, we present, for the first time, a case of breast carcinoma metastasizing to the prostate gland. Prostate needle core biopsy revealed infiltrative nests of neoplastic epithelioid cells, demonstrated by immunohistochemistry (IHC) to be positive for GATA3 and ER and negative for PSA and P501S. A prostate cocktail by IHC study demonstrated lack of basal cells (p63 and CK903) and no expression of P501S. The patient's previous breast needle core biopsy showed strong ER positivity and negative staining for PR and HER2. Similar to the prostate, the breast was negative for CK5/6, p63, and p40. This case demonstrates the importance of considering a broad differential diagnosis and comparing histology and IHC to prior known malignancies in the setting of atypical presentation or rare tumors.

Bilateral breast adenocarcinomas with EML4-ALK fusion in a patient with multiple metastases successfully treated with crizotinib: is lung the primary site?

Breast metastases from non-mammary cancers are rare, especially when they appear synchronously. Clinically, it is vitally important to accurately diagnose these patients, as this will directly influence their treatment and survival. We present a very rare and complex case of bilateral breast adenocarcinomas with an EML4-ALK fusion, which was diagnosed as bilateral breast metastases of non-small-cell lung cancer by immunohistochemistry and comprehensive genomic investigation. The patient was successfully treated with an ALK inhibitor (crizotinib); symptoms improved quickly after initiation of crizotinib therapy, and a partial response was observed after 3 months. The experience of diagnosis and treatment of this case indicates the importance and necessity of genomic investigations in such patients, and suggests that we need to consider the rare possibility of this kind of metastasis in order to provide optimal treatment.

Duodenal Adenocarcinoma Metastatic to the Breast: A Case Report

Duodenal adenocarcinoma, a very rare malignant gastrointestinal tumor, mainly metastasizes via the lymphatic system. Metastases from duodenal adenocarcinomas to the breast are very uncommon. A 31-year-old woman presented at our department with a left breast tumor. She had a past medical history of duodenal adenocarcinoma. Physical examination on admission confirmed a 2.5-cm-diameter tumor in the outer lower quadrant of the left breast. Computed tomography (CT) examination showed a soft lesion with tissue-like density and enlarged axillary lymph nodes. Local excision was performed to remove the breast lesion. The findings of cytologic, histologic, and immunohistochemistry examination indicated a breast metastasis from the previous duodenal adenocarcinoma. The patient was treated with palliative chemotherapy. Metastases from duodenal adenocarcinoma to the breast are rare. The diagnosis depends on medical history, imaging, and pathologic examination including immunohistochemistry. An accurate diagnosis is important to avoid unnecessary surgery.

Malignant Mesothelioma Mimicking Invasive Mammary Carcinoma in a Male Breast

Malignant mesothelioma is an uncommon tumor with strong association with asbestos exposure. Few cases of malignant pleural mesothelioma metastatic to the female breast have been reported. Herein, we presented, for the first time, a case of locally infiltrating malignant pleural mesothelioma forming a mass in the breast of a male as the first pathologically confirmed manifestation of the disease. Breast ultrasound revealed an irregular mass in the right breast which involves the pectoralis muscle. Breast core biopsy revealed a proliferation of neoplastic epithelioid cells mimicking an infiltrating pleomorphic lobular carcinoma. IHC studies showed the cells to be positive for calretinin, CK5/6, WT1, and CK7. The cells were negative for MOC-31, BerEp4, ER, and PR. A final diagnosis of malignant mesothelioma, epithelioid type, was rendered. This case demonstrates the importance of considering a broad differential diagnosis in the setting of atypical presentation with application of a panel of IHC markers.

Spectrum of Extramammary Malignant Neoplasms in the Breast With Radiologic-Pathologic Correlation

Although primary breast cancer is the most common malignancy identified by breast imaging, extramammary malignancies may also rarely be encountered. These uncommon lesions may reflect primary neoplasms of nonmammary origin as well as secondary metastatic lesions, and include lymphoma, melanoma, neuroendocrine tumors, gastrointestinal tract malignancies, and angiosarcoma among other entities. Malignant extramammary breast lesions may be encountered during routine mammographic screening, identified during the diagnostic evaluation of a palpable breast abnormality, or may be detected incidentally during imaging of other organs of interest. As such, the radiologist should have familiarity with the appearance of these lesions. This article focuses on a review of several of the most common extramammary metastases to the breast, as well as a few lesions that may develop as either primary or secondary lesions.

Breast metastasis as the first clinical manifestation of ileal neuroendocrine tumor. A challenging diagnosis with relevant clinical implications

Ileal neuroendocrine tumors are slow-growing grade 1 or, more rarely, grade 2 neuroendocrine tumors which, however, are frequently metastatic to regional lymph nodes and the liver. A few cases of ileal neuroendocrine tumors that are metastatic to the breast have also been reported in the medical literature. The knowledge of this uncommon clinical presentation is of great importance because it needs to be differentiated from primary breast carcinomas with neuroendocrine features, which represent completely different entities with a different therapeutic approach. The diagnosis of a breast metastasis from an ileal neuroendocrine tumor and its distinction from a well-differentiated primary neuroendocrine tumor of the breast is a challenging task for clinicians and pathologists. This workup is particularly difficult when the breast lesion is the first sign of malignancy. In the present paper, we describe the clinicopathological features of an ileal neuroendocrine tumor first presenting with a breast metastasis in a 50-year-old woman and we discuss the key diagnostic features for the differential diagnosis with primary well-differentiated neuroendocrine tumor of the breast. Moreover, we have reviewed the medical literature to give the reader a comprehensive overview on this topic.

Metastatic Melanoma Presenting as an Isolated Breast Tumor: A Study of 20 Cases With Emphasis on Several Primary Mimickers

Context.—The mammary gland can be a site of metastasis in patients with malignant melanoma, which is easily recognized microscopically if clinical information is available. Nonetheless, metastatic melanoma presenting as an isolated mammary tumor can be more challenging to diagnose because it can simulate a primary breast carcinoma clinically and morphologically.

Objective.—To review metastatic melanoma to the breast, presenting as primary breast carcinomas clinically and morphologically.

Design.—The authors report 20 cases of metastatic melanoma clinically presenting as breast tumors. Cases with widespread metastatic presentation were excluded.

Results.—Epithelioid and spindle cell tumors predominated, suggesting mammary ductal, papillary, or sarcomatoid carcinoma. Most cases (16 of 20) were submitted for consultation or second opinion owing to their unusual presentation in the breast, or to perform predictive/prognostic immunohistochemical assays. Seven cases had a remarkable phenotypic spectrum expanding the differential diagnosis to large cell lymphoma, leiomyosarcoma, medullary carcinoma, malignant schwannoma, and liposarcoma. Tumor cells were negative for cytokeratin stains and positive for S100 protein, HMB-45, and Melan-A. Negative staining was also observed for epithelial membrane antigen, CD45, desmin, estrogen and progesterone receptors, and human epidermal growth factor receptor 2.

Conclusions.—Metastatic melanoma may simulate a broad spectrum of primary breast malignancies. Although the application of a simple panel of antibodies assists in rendering the correct interpretation, lesions presenting as isolated breast tumors may introduce a significant diagnostic difficulty, especially when there is inadequate patient history and/or limited biopsy material. Further challenges are introduced by the extraordinary phenotypic plasticity of metastatic melanoma. Awareness of this pattern variance is essential to avoid inappropriate treatment, especially in cases simulating a “triple negative,” poorly differentiated carcinoma of the breast.

Bilateral breast metastasis as the first sign of recurrence of a cutaneous melanoma: A case report

Breast skin and parenchyma are metastatic sites for various tumours. Metastasis to the breast is rare, but it must be considered in the differential diagnosis of a breast mass. Melanoma is among the most commonly reported metastatic tumours of the breast. With the increasing incidence of melanoma, this complication is being encountered with greater frequency. 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. Along with a brief review of the literature, we report the case of a woman who presented with breast metastasis after 17 years as the first sign of recurrence of a melanoma. The aim of this study was to report the clinico-pathological features of a patient with metastatic melanoma to the breast. Metastasis can mimic either benign disease or primary malignancy and is often an unexpected diagnosis in a patient presenting with a breast mass. These masses generally indicate disseminated disease with very short survival. Metastasis should be suspected in patients with a breast mass and a prior history of melanoma even if the primary was removed a long time ago (17 years in our case). Fine needle aspiration cytology combined with immunohistochemistry is essential for the diagnosis of metastasis.

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.

Rectal carcinoma metastatic to the male breast after 7 years: case report

BACKGROUND

Colorectal cancer metastasis to a mammary location is very rare.

CASE REPORT

A 38-year-old male, who had undergone anterior resection of an advanced rectal carcinoma 7 years earlier, presented with a right mammary mass. Core needle biopsy of the mass indicated cytology consistent with breast adenocarcinoma. After neoadjuvant chemotherapy and modified radical mastectomy, pathology identified the mass as rectal carcinoma.

CONCLUSION

The authors highlight the difficulty of making an accurate diagnosis of rectal cancer metastasis to the breast of a male.

Male breast cancer

Male breast cancer (MBC) is a rare disease. However, as global populace ages, there is a trend to MBC increasing. Although aetiology is still unclear, constitutional, environmental, hormonal (abnormalities in estrogen/androgen balance) and genetic (positive family history, Klinefelter syndrome, mutations in BRCA1 and specially BRCA2) risk factors are already known. Clinic manifestation is painless hard and fixed nodule in the subareolar region in 75% of cases, with nipple commitment earlier than in women. Breast cancer has similar prognostic factors in males and females, among which axillary adenopathy (present in 40-55% cases) is the most important one. Although mammography, ultrasonography and scintigraphy can be useful tools in diagnosis; clinical assessment, along with a confirmatory biopsy, remains the main step in the evaluation of men with breast lesions. Infiltrating ductal carcinoma is the most frequent histological type. The established standard of care is modified radical mastectomy followed by tamoxifen for endocrine-responsive positive disease, although other options are being explored. While similarities between breast cancer in males and females exist, it is not appropriate to extrapolate data from female disease to the treatment of male. There is a need for specific multi-institutional trials to better understanding of clinicopathologic features and establishment of optimal therapy for this disease.

Patients with a history of epithelial ovarian cancer presenting with a breast and/or axillary mass

OBJECTIVE

A breast and/or axillary mass in a patient with epithelial ovarian cancer (EOC) may be due to an EOC breast metastasis or a second primary breast cancer. We sought to review our experience with patients with a history of EOC presenting with a breast and/or axillary mass to determine if clinical features differed between these entities.

METHODS

Between 1/90 and 10/07, 29 women with epithelial EOC presented with a breast or axillary mass, including 10 patients with EOC metastatic to the breast and/or axilla and 19 patients with a second primary breast cancer following their original EOC diagnosis. Clinicopathologic factors/survival were retrospectively abstracted from medical records.

RESULTS

The mean EOC disease-free survival (DFS) was 14.9 mo versus 77.4 mo (P<0.001) for patients with recurrent epithelial ovarian cancer metastatic to the breast and/or axilla and patients with a second primary breast cancer, respectively. Similarly, the mean interval between diagnosis of EOC and the breast and/or axillary event was 31.2 mo versus 70.7 mo for those patients who had metastatic recurrent EOC and those patients with breast cancer (P=0.02). Patients with a second primary breast cancer were more likely to be diagnosed on mammogram and have a family history of breast and ovarian carcinoma than patients with metastatic EOC to the breast and/or axilla (14/19 [73.7%] versus 2/9 [22.8%], P=0.02; and 12/18 [66.7%] versus 2/10 [20%], P=0.05, respectively). Median overall survival for patients with EOC metastasis was 26 mo but was not yet reached for those patients with a second primary breast cancer. On univariate analysis, an ovarian cancer DFS of 12 mo or more and the performance of breast/axillary surgery were associated with a significantly longer overall survival (P=0.01 and 0.02, respectively), whereas an elevated CA125 level at the time of the breast/axilla event and the presence of EOC metastases to the breast and axilla were significant negative predictors of survival (P=0.01 and 0.05, respectively).

CONCLUSION

The interval between EOC diagnosis and the breast and/or axilla event, an elevated CA125 level, and a family history of breast and/or ovarian cancer may help differentiate patients with metastatic EOC to the breast and/or axilla from those patients with a second primary breast cancer. The presence of a metastatic EOC portends a poor prognosis.

Rare case of breast tumor secondary to rectal adenocarcinoma

Primary breast cancer is the most common malignancy in women. Metastatic cancer to the breast is very rare. Colorectal cancers usually metastasize to the liver and the lung; other sites of metastasis from colon cancer are uncommon and are usually found in association with extensive liver and/or lung metastases. This is a report of a rare case of aggressive rectal cancer with metastasis to the breast without liver or lung metastases.

The histological diagnosis of metastases to the breast from extramammary malignancies

This study aims to review histological and immunohistochemical features that are useful in the diagnosis of metastases to the breast. Histological features were compared between non-haematological metastases to the breast and 100 consecutive core biopsy specimens of primary invasive carcinomas of the breast. 18 non-haematological metastases to the breast were diagnosed over a 10-year period (0.3% of malignant mammary tumours). Elastosis and carcinoma in situ were seen only in primary mammary cancers. Two-thirds of tumours had features raising the possibility of metastasis, such as clear cell carcinoma suggestive of renal origin and small cell carcinoma suggestive of pulmonary origin. The features observed in haematological metastases are also described. Immunohistochemical panels to distinguish mammary carcinoma (oestrogen receptor, gross cystic fluid protein-15) from common metastases to the breast, including carcinoma of the lung (thyroid transcription factor-1), malignant melanoma (S100, HMB45, melan-A) and ovarian serous papillary carcinoma (Wilms' tumour 1), are discussed. The pathologist has a key role in considering the diagnosis of metastasis to the breast if the histological features are unusual for a primary mammary tumour. The clinical history is vital in some cases. Immunohistochemistry plays a useful supplementary role.

Intraductal Spread by Metastatic Islet Cell Tumor (Well-differentiated Pancreatic Endocrine Neoplasm) Involving the Breast of a Child, Mimicking a Primary Mammary Carcinoma

Metastases to the breast are rare, accounting for an estimated 1% to 2% of malignant breast neoplasms. The key histopathologic features supporting a metastasis to the breast have been stated to be the absence of elastosis, presence of a pushing border (circumscribed lesion), multiple satellite foci, lymphatic emboli, and, most importantly, the absence of an in situ carcinoma component. We report a unique case of a pancreatic islet cell tumor metastatic to the breast of an 18-year-old girl. Clinically, the patient was thought to have a mammary primary because on her initial biopsy, the metastasis grew within mammary ducts and colonized a complex sclerosing lesion, simulating an in situ component. However, review of slides from the prior pancreatic neoplasm, review of slides from the subsequent mastectomy, and use of immunohistochemistry allowed recognition of the lesion as a metastasis, which proved to be the first clinical manifestation of a systemic relapse. To our knowledge, this is the second case of islet cell tumor reported to metastasize to the breast, and the first report of a metastasis proven to have grown within existing ducts of the breast by immunohistochemistry.

Breast metastases as the first sign of recurrence of a cutaneous melanoma

Malignant melanoma is the most rapidly increasing cancer in the world. Metastatic disease occurs in 20% of patients, and prognosis in these cases is poor. We report the case of a woman who presented breast metastasis as the first sign of recurrence of a melanoma.

[Breast metastases]

Metastases in the breast resulting from extra-mammary tumours are infrequent, and the prognosis is poor. The main challenge in diagnosis is to differentiate between this condition and that of primary breast cancer so as to avoid unnecessary surgery. We present two cases that we encountered recently.

Fine needle aspiration biopsy diagnosis of metastatic neoplasms of the breast. A three-case report

Metastases to the breast are unusual lesions that make up approximately 2% of all malignant mammary neoplasms and may mimic both benign and malignant primary neoplasms from a clinical point of view, as well as in imaging studies. Arriving at a correct diagnosis is therefore essential in order to establish appropriate management.

We present three cases of metastatic neoplasms diagnosed through fine needle aspiration biopsy and immunocytochemistry. The cytological diagnoses were: medulloblastoma in an 18-year-old woman, melanoma in a 26-year-old man, and an exceptional case of ovarian sarcoma originating from a granulosa cell tumor with metastases to both breasts. A metastatic disease should be considered in the differential diagnosis of a palpable mass in the breast, especially if there is a history of an extramammary malignant neoplasm. Fine needle aspiration biopsy is the method of choice for the management of these cases.

Whenever possible the exam of the material obtained should be compared to the previous biopsy, which is usually enough to arrive at a correct diagnosis, thus preventing unnecessary surgical procedures.

Current Practical Applications of Diagnostic Immunohistochemistry in Breast Pathology

In recent years, immunohistochemistry has assumed an increasingly prominent role in diagnostic breast pathology. Immunohistochemistry is now frequently used in the evaluation of many epithelial proliferations of the breast. Common applications include the use of myoepithelial markers to evaluate for stromal invasion, E-cadherin to distinguish between ductal and lobular neoplasia, high molecular weight cytokeratins to differentiate usual ductal hyperplasia from ductal carcinoma in situ, immunohistochemical profiles to characterize site of origin of metastatic carcinomas, and cytokeratin stains to detect metastases in sentinel lymph nodes. Recent advances, practical considerations, and potential pitfalls in the use of immunohistochemistry in these five diagnostic categories are discussed herein.