Secondary neoplasms of the breast: a survey of the 20th Century

Bilateral breast metastases from anaplastic lymphoma kinase-positive lung cancer in a male: a case report

BACKGROUND

Distant metastases from lung cancer are commonly found in the brain, bone, and liver. Metastases to the breast from non-mammary malignancies are extremely rare, and their clinical presentations remain unclear.

CASE PRESENTATION

We herein report a case of bilateral breast metastases from anaplastic lymphoma kinase-positive advanced lung cancer in a 51-year-old Japanese male patient. During the course of systemic treatment for advanced lung cancer, computed tomography revealed bilateral breast enlargement without contrast enhancement, a finding consistent with gynecomastia. While other metastatic lesions responded to chemotherapy, both breast masses grew vertically like nodules. The breast masses were immunohistochemically diagnosed as metastases from lung cancer and were removed surgically. Simultaneous bilateral breast metastases from malignancies of other organs, like ones in this case, have rarely been described.

CONCLUSIONS

It is important to keep in mind that breast metastases from nonmammary malignancies are a possible explanation for unusual breast findings in a patient with a history of malignancies.

Metastatic Neoplasms to the Breast

OBJECTIVE

When the clinical presentation is related to the metastatic mass and a radiologically solitary tumor focus is detected, especially in cases where clinical information is not taken into account or is insufficient, if a possible metastatic neoplasia is not kept in mind then it is possible to evaluate the tumor as a primary breast neoplasm. In this study, it is aimed to present our cases of non-hematopoietic metastatic neoplasms and to evaluate the clinicopathological features that may aid in distinguishing metastatic from primary neoplasms.

MATERIAL AND METHODS

This study includes cases diagnosed with metastatic non-hematopoietic breast neoplasm in breast resection materials in our center, between the years 2010-2023. All cases were analyzed retrospectively by evaluating clinicopathological features.

RESULTS

Of the 15 subjects included in the study, 11 (73%) were female and 4 (27%) were male. The mean age of the patients were 46.9 ranged from 22 to 63 years. The most frequent metastatic malignancy was carcinoma (60%), followed by melanoma (33%) and sarcoma (7%). Of the 9 patients with metastatic carcinoma, the primary tumor originated from the lungs in 4, from gastrointestinal system in 2, female genital tract in 2, and kidney in 1 patient. Sarcoma diagnosis was given in a single patient and the histology was a leiomyosarcoma originating from kidney.

CONCLUSION

A careful histomorphological and immunohistochemical evaluation and a detailed examination of the clinicoradiological data are critical to establish the right course in patient management, treatment plan and to correctly predict the prognosis.

Unusual Metastasis of Gastric Signet Ring Cell Carcinoma to the Breast: A Case Report of a Young Moroccan Patient

Although gastric cancer is known to be an aggressive tumor that can spread throughout the body, breast metastases are uncommon. This entity is rarely reported in the literature, with an estimated incidence of 0.5 to 1.3%. We report a case of a rare association between a gastric subtype of signet ring cell carcinoma and metastasis to the breast. This uncommon situation is only documented through case reports. Most breast metastases have been detected after diagnosis of primary gastric cancer, during the first year. Several risk factors have been suggested to explain the aggressive behavior of these tumors, which correlates with very poor prognosis and short survival. We report the case of a 22-year-old female patient presenting with widespread metastatic gastric signet ring cell carcinoma with an unusual secondary site in the breast. The diagnosis was confirmed by immunohistochemistry (IHC) and radiology, and the patient was treated with palliative chemotherapy in accordance with the decision of the multidisciplinary tumor board.

Solitary Metastasis to the Breast From Thigh Myxoid Liposarcoma

Metastasis to the breast from non-mammary malignancies are rare and suggestive of advanced disease. Accurate and prompt diagnosis of breast metastasis can provide important prognostic information and guide treatment planning. Interestingly, in contrast to primary breast malignancies, non-mammary metastatic breast lesions often have benign-appearing imaging characteristics. Knowing a patient's clinical history and having prior breast imaging studies for comparison is important for making accurate assessments and appropriate recommendations. Imaging-guided biopsy is often indicated for definitive tissue diagnosis. We report a rare case of solitary metastasis to the breast from thigh myxoid liposarcoma.

A Spectrum of Metastases to the Breast: Radiologic-Pathologic Correlation

Metastases to the breast from non-mammary origin are rare. The majority of these lesions appear as secondary manifestations of melanoma and lymphoma, followed by lung carcinomas, gynecological carcinomas, and sarcomas. There has been a steady trend of an increase in diagnosis of intramammary metastases owing to the current advances in imaging technology. Imaging features depend on the type of primary neoplasm and route of dissemination, some of which resemble primary breast cancer and benign breast entities. There are certain imaging features that raise the level of suspicion for metastases in the correct clinical context. However, imaging manifestations of intramammary metastases do not always comply with the known classic patterns. The aim of this review is to clarify these features, emphasizing radiologic-pathologic correlation and a multidisciplinary approach, since most cases are found in patients with advanced disease.

Metastasis of endometrial cancer to breast: A rare case

Only 2% of all breast cancers are metastatic, making them extremely uncommon. They are frequently mistaken for a primary breast tumor. Although it has been observed, metastatic spread from primary uterine cancers is extremely uncommon. In the literature, our case represents the fourth endometroid adenocarcinoma metastasis from the uterus. Clinical, pathological, and immunohistochemical examination and management of metastatic endometrioid adenocarcinoma of the uterus' extragenital organ were described in this 69-year-old patient's case. Immunohistochemical analysis was performed on a breast biopsy taken from the patient who underwent therapy and discovered a breast mass two years later. Metastatic endometrial adenocarcinoma was diagnosed with negative signs pointing to mammaglobin, GCDFP-15 and GATA3 breasts and markers indicating endometroid adenocarcinomas such as p53, PAX8 and VIMENTIN support. As a result, a thorough clinical history is needed, with special attention to diagnoses of concurrent or prior malignancies, along with clinical examination, appropriate radiological evaluation, and immunohistochemistry. This is necessary to prevent unnecessary surgery, to provide appropriate systemic treatment, to ensure correct diagnosis, and to manage treatment.

Breast metastasis from endometrial clear cell carcinoma: A case report and review of the literature

Metastasis to the breast from extra-mammary malignancies are rare, accounting for less than 1% of all breast cancers. Endometrial cancer, a common gynecological malignancy, often spreads to the pelvis, abdominal lymph nodes, peritoneum or the lungs. Endometrial metastasis to the breast is extremely rare, and while there have been isolated case reports of endometrial serous carcinoma with breast metastasis, it has not been reported in the case of clear cell carcinoma. We present a rare case of a 70 year old Chinese lady who had a metastatic endometrial clear cell carcinoma with metastasis to the breast, mimicking an inflammatory breast cancer clinically. We reviewed the current literature and describe the challenges in differentiating primary from metastatic breast lesions, as well as clinical, radiological and histopathological features that may help to differentiate the two. Tumour metastasis to the breast via lymphatic or hematogenous route can affect their radiological features: the former mimicking inflammatory breast cancer and the latter with features similar to benign breast lesions. Regardless, histological features with immunohistochemical staining is still the gold standard in diagnosing metastatic breast lesions and determining their tissue of origin. Breast metastases from extra-mammary malignancies are uncommon and it is even rarer for endometrial clear cell carcinoma to spread to the breast. Nonetheless, this case highlights the importance of keeping an open mind and engaging a multidisciplinary team for the care of complex patients.

Metastatic spread of serous ovarian carcinoma to the bilateral breasts: a rare presentation

A woman presented with a mass in her right breast. She had previously been treated with carboplatin, paclitaxel and bevacizumab for serous ovarian carcinoma diagnosed 5 years previously and was currently on maintenance olaparib. A right breast mammogram demonstrated periareolar skin thickening and the physical examination revealed an erythematous, non-blanching cutaneous lesion. A punch biopsy revealed high-grade serous carcinoma of ovarian origin, positive for PAX-8, WT-1 and p53. Positron emission tomogram-CT scan showed diffusely increased fluorodeoxyglucose uptake in the right breast. She was treated with external beam radiation therapy to the right breast and regional lymphatics and received 5200 cGy in 20 fractions to the right breast and supraclavicular region with good response. Two weeks after completing radiation therapy, she presented with a new lesion inferior to her left areola, concerning for metastasis to the contralateral breast. Subsequent biopsy of the left breast identified metastatic serous ovarian carcinoma for which she received an additional 5200 cGy in 20 fractions to the breast.

Breast Metastasis of Lung Cancer After Computed Tomography-Guided Core Needle Biopsy: A Case Report

Background

Needle tract metastasis is a rare complication following percutaneous procedures for malignancy.

Case Summary

This report describes a 49-year-old female with a lump on her right breast. Mass core needle biopsy showed the specimen was an invasive carcinoma, and mastectomy with sentinel lymph node biopsy was performed. What is special about this case was that the patient reported a history of lung cancer and the position of the breast mass was the puncture site of computed tomography-guided core needle biopsy for lung cancer. Immunostaining of paraffin specimen findings indicated the breast mass as a result of lung carcinoma metastasis. The patient's medical history indicated that the malignant tumor in the breast was a core needle tract pulmonary metastasis. The patient underwent the examination and received therapy based on the lung cancer metastasis principle. At 9 months from breast surgery, the patient is alive, in good condition, and with stability of the disease.

Conclusions

This patient was misdiagnosed. Careful medical history review and multidisciplinary team discussions are important, especially for patients with a history of cancer or invasive operation.

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.

Unusual presentation of a small cell lung cancer with bilateral breast metastases: Case report and a brief review of the literature

Small cell lung cancer (SCLC) is a smoker's disease and occurs almost exclusively in smokers. SCLC is a high-grade neuroendocrine tumor and commonly presents as a central tumor with bulky mediastinal adenopathy. It is notorious for causing widespread disease and paraneoplastic syndromes. The usual sites of metastasis include the liver, brain, bone, and adrenals. SCLC presenting with breast metastasis is unusual; however, there are reports of unilateral and bilateral breast metastases. SCLC with bilateral breast metastases is extremely rare, with only five previously reported cases available in the literature. We are taking this opportunity to report and add to the growing literature on the unusual presentation of a small cell lung cancer with bilateral breast metastases.

Dedifferentiation in Breast Metastasis of Endometrial Carcinoma: A Diagnostic Dilemma

Most breast tumors are primary to this site; breast metastasis of endometrial origin is extremely rare. Low-grade endometrioid endometrial carcinomas can undergo dedifferentiation to undifferentiated carcinoma but such transformation at a metastatic site has been reported previously in only 2 cases. We report a case of dedifferentiation occurring in an isolated solitary breast metastasis of a low-grade endometrioid endometrial carcinoma. A 64-yr-old woman presented with a breast mass 2 yr after initial diagnosis of a grade 1 FIGO stage IIIA endometrioid endometrial carcinoma. Ultrasound guided biopsy of the breast mass showed a grade 1 endometrioid carcinoma which was diffusely estrogen receptor and PAX8-positive, consistent with metastasis from the previous endometrial carcinoma. The tumor initially responded to Letrozole therapy but then abruptly increased in size. Mastectomy revealed a poorly differentiated malignant tumor with morphology and immunophenotype (including loss of ARID1A and ARID1B immunoreactivity) consistent with undifferentiated endometrial carcinoma with no residual low-grade component. Awareness of the phenomenon of dedifferentiation of endometrial carcinoma in a metastatic site is important to avoid misdiagnosis as a primary breast cancer or metastasis from another primary site.

Osteosarcoma of the Right Lower Femur With Breast and Axillary Lymph Node Metastasis: A Rare Case Presentation

Osteosarcoma is the most common skeletal malignancy and commonly metastasis to lung and bone. Here we report a case of osteosarcoma of the right knee with metastasis to the lower and inner quadrant of the breast along with axillary, mediastinal, retroperitoneal and inguinal lymphadenopathy with lung and liver metastasis. The diagnosis of breast metastasis was confirmed by ultrasonography-guided biopsy and immunohistochemistry (IHC). So this report highlights the rarest metastasis to breast and axillary lymph node from an osteosarcoma of the right knee primary.

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.

Cervical squamous cell carcinoma metastasis to the breast - A case report from Uganda Cancer Institute

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Cervical squamous cell carcinoma does metastasize to the breast.

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Vagina exam is essential in a patient who presents with a breast mass.

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Immunohistochemistry is key in differentiating a primary lesion from a metastasis.

Ovarian Cancer With Breast Metastasis and Two Pathogenic Variants of BRCA1 Gene

Ovarian cancer is the second most common gynecologic cancer after uterine cancer in the United States. Ovarian cancer ranks sixth in cancer deaths among women, accounting for more deaths than other female reproductive system cancers. Breast metastasis in ovarian cancer is a rare presentation and predicts a poor prognosis and challenging management. Our case is a 42-year-old Chinese woman with high-grade serous ovarian carcinoma that presents with metastasis to the breast during the course of her illness. Genetic evaluation of the ovarian tumor showed two BRCA1 pathogenic variants. Germline pathogenic variant of c.2110_2111DelAA and a somatic variant of c.4071_4096+14del40. Our patient was offered different treatment regimens but showed progression of her disease. The low survival rate and high recurrence rate in ovarian cancer show that we still need to investigate our current approved treatments. Our report aims to shed light on the genetic evaluation of ovarian tumors and treatment options available in refractory cases of progressive ovarian cancer. Furthermore, we explain our investigational therapy regimen and the reasoning behind it.

Bilateral breast metastases as the first manifestation of an occult pancreatic neuroendocrine tumor

Breast metastases are uncommon findings compared to primary breast cancer and in particular bilateral secondary breast lesions from neuroendocrine tumor (NET)s are extremely rare with just less over 13 cases described in literature. We reported herewith the case of a 54-year-old woman who presented to our Breast Unit after noticing multiple, mobile, bilateral breast lumps. Imaging studies confirmed the presence of multiple, circumscribed, bilateral breast masses with slightly spiculated margins, classified as suspicious for malignancy (BI-RADS 4). A tru-cut biopsy was carried out on the largest lesion of each side and histopathologic and immunohistochemistry examination was consistent with metastases from pancreatic neuroendocrine tumor (PNET). Total-body CT revealed the presence of a mass located in the pancreatic body - tail with associated abdominal lymphadenopathies and multiple secondary nodules in bilateral breast and in the liver. Stage IV disease was diagnosed, patient did not undergo surgery and started LAR – octreotide therapy. Although rare, breast metastases from NETs represent an important diagnostic challenge for practitioners because of the difficulty to differentiate from a primary breast carcinoma or even from benign breast lesions. Clinicians should be aware of the possibility of bilateral breast metastases in differential diagnosis of breast lesions in order to ensure the correct diagnosis and the most appropriate management of these patients.

Complex Differential Diagnosis between Primary Breast Cancer and Breast Metastasis from EGFR-Mutated Lung Adenocarcinoma: Case Report and Literature Review

We present a case of a woman with epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma who received gefitinib for 2 years and obtained a partial response. The patient then developed liver metastasis and a breast lesion, displaying high estrogen receptor (ER) expression and harboring the same EGFR mutation. From the radiological studies, it was not possible to make a differential diagnosis between primary breast cancer and breast metastasis from lung cancer. After the removal of the breast nodule, thanks to the clinical history, radiology, and above all, molecular and immunohistochemical investigations, a diagnosis of breast metastasis from lung adenocarcinoma was made. This case emphasizes the importance of a comprehensive clinical, pathological, and molecular analysis in the differential diagnosis between primary breast cancer and metastases from extramammary tumor to guide adequate treatment decision making.

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.

Metastasis to breast from ovarian cancer and primary ovarian cancer concurrently diagnosis

Metastasis to breast from ovarian cancer is very rare, and it is very difficult to distinguish the primary breast cancer from the secondary one. In our case, a 61-year-old woman presented to the hospital with complaints of lower abdominal pain and distention. Abdominal-pelvic computed tomography (CT) imaging revealed a solid ovarian cystic tumor with numerable ascites in the abdominal cavity and disseminated peritoneal carcinomatosis. To confirm the presence of metastasis in other organs, a preoperative imaging studies including chest CT was performed. Chest CT imaging revealed an enlargement of both the axillary lymph nodes (r/o metastatic lymphadenopathy) and breast imaging studies (breast sonography and mammography) revealed masses penetrated the pectoralis major muscle in the left breast and metastatic lymphadenopathy in Lt axilla. The core needle biopsy result of breast lesion showed unknown origin carcinoma with micropapillary features and no psammoma bodies. So, we could not distinguish primary breast cancer and breast metastasis from ovarian cancer because breast metastasis from ovary could be contained psammoma bodies, generally. Although the possibility of primary breast cancer could not be ruled out absolutely, the neoadjuvant chemotherapy included Paclitaxel and Carboplatin is known to be effective for both breast and ovarian cancer. So after neoadjuvant chemotherapy, mastectomy concurrently with ovarian cancer surgery was performed. The histopathologic features of the ovaries and breast were similar and psammoma bodies also could be observed, which were not detected in previous core needle biopsied specimen. And lymph nodes from the breast and the ovaries also showed consistent findings. Combined with histopathologic report and medical records, the final diagnosis confirmed as a metastasis of ovarian cancer to breast. After surgery, the patient has continued with metastatic ovarian cancer specific treatment. Breast metastatic tumors must be distinguished from primary breast tumors to avoid any unnecessary surgery. It might be difficult to diagnosis precisely by using only core needle biopsy because of inadequate specimen volume. Although surgical resection may be effective for both diagnosis and palliative treatment, further studies focused on less invasive biopsy are needed for exact histopathological diagnosis.

Three Cases of Breast Metastases from Lung Cancer and Systematic Review of the Literature

Despite the high prevalence of lung cancer among other primary tumors, metastasis of this particular malignancy in the breast is very rare. We report three new cases of lung cancer with breast metastases and discuss radiological and clinical findings. Radiologically, each case displayed different characteristics. First, one of them had bilateral superficially and deeply located irregular lesions. Second, the patient presented with findings similar to inflammatory breast cancer. The third case had a circumscribed mass, resembling a benign complicated cyst. To guide clinicians for proper patient management, radiologists should be aware of the scope of typical and atypical imaging findings of metastatic involvement of the breast.

A case report of multiple bilateral breast metastases after colorectal cancer

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CRC metastasizes commonly to the regional lymph nodes, liver, lung, and rarely to breast.

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The radiologic investigations can play a role in the differentiation between the diagnosis of primary breast cancer and metastases.

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Immunohistochemically, the majority of breast adenocarcinomas are: negative for CDX2 and CK20 and positive for CK7, while colorectal adenocarcinomas are: positive for CDX2 and CK20, and negative for ER, PR, HER2, and CK7.

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The management plan of CRC metastases to the breast is complex and requires a multidisciplinary team.

Introduction and importance

Although primary breast cancer is the most common tumor in women, breast metastases are rare findings. We report the first case in English literature with CRC metastases to the breast and adrenal gland concurrently.

Case presentation

A 42-year-old Caucasian female complained of abdominal pain over the last 3 days. Her history was remarkable for stage 2 colon cancer and she was free of disease for 2 years before the presentation, due to receiving Surgical-chemotherapy. The radiologic investigation showed a well-defined cystic mass in the left adrenal gland and left breast nodule. After adrenalectomy, the diagnosis of the mass was metastatic mucinous adenocarcinoma. During the surgical preparation, bilateral breast lumps were noticed. Histopathology of breast mass showed mucinous adenocarcinoma. Immunohistochemical staining revealed that the neoplastic gland was positive for CDX2, CK20, and P53 mutation and negative for CK7, PR, ER, and HER2. Overall, the diagnosis was metastatic colorectal adenocarcinoma to the breast.

Clinical discussion

Metastatic lesions in the adrenal gland tend to be bilateral with irregular shape. Breast metastases are singular unilateral lesions with predominance in the left breast. Biopsy and immunohistochemistry make the final diagnosis.

The management plan is complex and depends on many factors like the general condition of the patient and the presence of other metastases. However, breast metastases may be a clinical clue to disseminated disease.

Conclusion

Breast metastases should be in the differential diagnosis in patients with a history of colorectal adenocarcinoma, in order to provide the appropriate clinical care.

Breast Metastasis of Gastric Signet Ring Cell Carcinoma: A Case Report and Literature Review

Breast metastasis from gastric signet ring cell carcinoma is extremely rare in clinical practice. The estimated incidence is 0.5-1.3%. There are few cases reported in the literature (approx. less than 60) of breast metastasis from gastric signet ring cell carcinoma, and due to the rare association between gastric cancer and its extension to the breast, it is difficult to establish the diagnosis. Clinical history, histological findings, and immunohistochemical markers are helpful in distinguishing primary breast cancer from breast metastasis of gastric cancer. The treatment for breast metastasis from gastric carcinoma remains controversial. The prognosis of breast metastasis from gastric carcinoma is generally poor. We report a case of breast metastasis of gastric signet ring cell carcinoma in a 38-year-old woman. She started chemotherapy with ramucirumab, paclitaxel, and irinotecan. Three months later, a combined 2-[¹⁸F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography showed a complete response. This is the first reported case of breast metastasis from gastric signet ring cell carcinoma with a complete response.

Metastatic ovarian cancer spreading into mammary ducts mimicking an in situ component of primary breast cancer: a case report

Background

Accurate diagnosis of metastatic tumors in the breast is crucial because the therapeutic approach is essentially different from primary tumors. A key morphological feature of metastatic tumors is their lack of an in situ carcinoma component. Here, we present a unique case of metastatic ovarian carcinoma spreading into mammary ducts and mimicked an in situ component of primary carcinoma. To our knowledge, this is the second case (and the first adult case) confirming the in situ-mimicking growth pattern of a metastatic tumor using immunohistochemistry.

Case presentation

A 69-year-old Japanese woman was found to have a breast mass with microcalcifications. She had a known history of ovarian mixed serous and endocervical-type mucinous (seromucinous) carcinoma. Needle biopsy specimen of the breast tumor revealed adenocarcinoma displaying an in situ-looking tubular architecture in addition to invasive micropapillary and papillary architectures with psammoma bodies. From these morphological features, metastatic serous carcinoma and invasive micropapillary carcinoma of breast origin were both suspected. In immunohistochemistry, the cancer cells were immunoreactive for WT1, PAX8, and CA125, and negative for GATA3, mammaglobin, and gross cystic disease fluid protein-15. Therefore, the breast tumor was diagnosed to be metastatic ovarian serous carcinoma. The in situ-looking architecture showed the same immunophenotype, but was surrounded by myoepithelium confirmed by immunohistochemistry (e.g. p63, cytokeratin 14, CD10). Thus, the histogenesis of the in situ-like tubular foci was could be explained by the spread of metastatic ovarian cancer cells into existing mammary ducts.

Conclusion

Metastatic tumors may spread into mammary duct units and mimic an in situ carcinoma component of primary breast cancer. This in situ-mimicking growth pattern can be a potential pitfall in establishing a correct diagnosis of metastasis to the breast. A panel of breast-related and extramammary organ/tumor-specific immunohistochemical markers may be helpful in distinguishing metastatic tumors from primary tumors.

Metastatic renal cell carcinoma initially presenting as a unilateral breast lump

Breast metastasis from primary renal cell carcinoma is a rare entity and infrequently reported in the literature. We present a case of a 65-year-old lady who presented to breast clinic with a 4-month history of rapidly growing right sided breast lump. She previously had a left mastectomy for breast cancer and a hysterectomy for endometrial cancer. Radiological evaluation with mammography and ultrasound revealed a large heterogeneous right breast lump with prominent vascularity which was biopsied. Histopathological and immunohistochemical features were not supportive of a primary breast carcinoma and favored metastasis from a renal tumor. The patient was unfortunately admitted to hospital due to increasing confusion and neurological symptoms and underwent whole-body cross-sectional CT imaging which demonstrated a giant tumor originating from the right kidney with associated intrathoracic, breast and intracranial metastasis. She was diagnosed with eosinophilic variant metastatic renal cell carcinoma. This case highlights the importance of considering alternative diagnoses to primary breast carcinoma in the context of an initial presentation of a unilateral breast lump.

Somatostatin receptor-positive breast lesions on 68Ga-DOTATATE PET/CT

OBJECTIVE

This study sets out to evaluate patients with increased uptake in breast lesions on ⁶⁸Ga-DOTATATE PET/CT (DOTA PET) and determine the clinical significance of somatostatin receptor (SSTR) positive breast lesions.

METHODS

We retrospectively evaluated all patients with increased SSTR uptake in breast lesions on DOTA PET. Patients with physiological (e.g., lactation) or normal variant breast uptake (e.g., mild diffuse glandular uptake) were excluded. The maximum standard uptake value (SUVmax) was calculated using a manually drawn region of interest in the most intense uptake of breast lesions. All lesions were correlated with breast imaging, including mammography and ultrasonography. Histopathological correlation was performed if the lesion was suspicious for malignancy. Lesions were followed up radiologically (1-8 years).

RESULTS

Out of 1573 retrospectively analyzed DOTA PET scans, the incidence of SSTR + breast lesions was measured as 1.1% (n = 18); however, 4 of 18 patients were excluded due to the lack of final diagnosis of lesions. The median age was 35 (range 14-58 years), and all patients were female. The median SUVmax of SSTR + breast lesions was 5.2 (range 1.5-12.6) for a total of 14 patients. Twelve patients had a single SSTR + breast lesion, while 2 patients had multiple SSTR + lesions on bilateral breasts. In 6 patients, single SSTR + lesions were considered as fibroadenoma; in 2 patients, multiple SSTR + lesions were considered as metastases of NET, based on correlative breast imaging. In 6 patients, histopathological confirmation was needed for the final diagnosis. Histopathologic findings confirmed fibroadenoma in 4 patients by biopsy, in 1 patient with surgical removal of the lesion. The last patient who had a history of IDC was diagnosed with a recurrence of IDC with biopsy. The median SUVmax was 5.1 (range 1.5-9.4) for malignant breast lesions and 5.4 (range 2.2-12.6) for benign breast lesions.

CONCLUSION

SSTR + breast lesions on DOTA PET are rarely seen in clinical practice. Uptakes of breast lesions in our cases were variable and not useful for differential diagnosis of lesions. It seems that SSTR + breast lesions should be evaluated with clinical and radiological characteristics, and correlative breast imaging and/or histopathological verification should be performed for suspicious lesions to avoid misdiagnosis.

Breast Metastases: Updates on Epidemiology and Radiologic Findings

Purpose The aim of this study was to report the prevalence of secondary breast malignancies and analyze their radiological characteristics. Materials and methods We collected 42,505 pathological reports of mammary biopsies performed from January 2000 to January 2019 in our hospital database, from which we screened reports of secondary cancer of the breast. We collected and analyzed imaging data from computed tomography (CT), ultrasound (US), and mammography. Mammograms, CT scans, and US images were reviewed by two breast radiologists. Prevalence of secondary breast malignancy among suspicious breast masses and all breast malignancies were calculated. Results Out of 42,505 histopathology reports from mammary biopsies, we found 19,354 malignancies. We identified 33 cases of secondary breast cancers (0.08% of suspicious breast lesions, 0.17% of breast malignancies). Most common metastases were from lymphoma (23 cases, 0.05% of suspicious breast lesions, 0.12% of breast malignancies) and melanoma (six cases, 0.01% of suspicious breast lesions, 0.03% of breast malignancies). All secondary lesions were hypoechoic on US and showed high density on mammogram. On CT, 83% of the lesions appeared solid/dense, and 17% were mixed, alternating areas of iso/hyperdensity with areas of hypodensity. Conclusion Secondary breast cancer had a prevalence of 0.17% among all breast malignancies. No specific imaging features, characteristic of secondary breast cancer, were found.

Rare case of a male breast tumour secondary to poorly differentiated rectal adenocarcinoma

Rectal cancer metastasis to the breast is rare. A case history is presented of a 57-year-old man with breast metastases from rectal carcinoma. However, this patient did not have metastasis in common metastatic sites, such as the liver, lung, and other organs. The patient had undergone chemotherapy for advanced rectal carcinoma 6 months earlier and presented with a mammary mass. An ultrasound-directed core needle biopsy of the breast mass was performed. Cytology indicated an adenocarcinoma with poor to moderate differentiation in the breast mass Immunohistochemistry (IHC) showed cytokeratin (CK) expression with a pattern that is characteristic of colorectal tumours: CK7(−), CK20(+), CDX2(−), Villin(+) TOPOII(−), and a Ki-67 index of 30%. The 3 main breast tumour markers were negative. Based on these histopathological and immunohistochemical findings, the patient was diagnosed with breast metastases from rectal carcinoma. Distant metastasis should be taken into account when a patient has a medical history of rectal adenocarcinoma, even when a rare metastasis site is involved. We should be vigilant when patients have some features that are favorable for metastasis. Histopathological characteristics and immunohistochemical tests are helpful for diagnosis. Regardless of surgical treatment after neoadjuvant chemotherapy, standard chemotherapy regimens for intestinal tumors, and EGFR molecular-targeted drugs, there is no obvious effect and the prognosis is poor. The treatment method needs further study.

Breast Metastasis from Neuroendocrine Carcinoma of the Lung: A Case Report and Review of the Literature

Breast metastasis originating from non-mammary tumors is an uncommon event accounting for 0.5-6.6% of all breast neoplasms. The primary malignancies that reportedly metastasize to the breast most frequently are hematologic malignancies, such as leukemia and lymphoma and malignant melanoma. Breast cancer metastasis resulting from a primary lung neoplasm is significantly less commonly described in the literature. Herein, we present the unusual case of a patient with metastatic disease to the breast from a primary lung tumor.

The rare entity of bilateral and unilateral neuroendocrine metastases to the breast: a case series and literature review

Introduction

Primary neuroendocrine neoplasms (NENs) in the breast are very rare. Until 2011, the prevalence was 0.1% of all breast lesions and 1% of all NENs, whereas metastatic breast NENs represent 1%–2% of all breast tumours. However, it seems that over the last 5 years the diagnostic frequency of breast NENs has increased, probably for more alert specialists and advanced diagnostic tools, leading to a prevalence of 2%–5% of diagnosed breast cancers, mostly in the elderly population. Breast metastases from extramammary malignancies are uncommon and bilateral ones are even more uncommon, with few reported in the literature. We describe four clinical settings of breast metastases from different NENs and the multidisciplinary approach for diagnosis and treatment.

Methods

Four patients were found to have NEN primaries metastasised to the breast. A literature review was conducted to identify similar cases and characterise breast metastases from neuroendocrinal tumors (NETs).

Results

Two patients presented with bilateral breast metastases (one with well-differentiated panNET and another with atypical lung carcinoid) and two had unilateral (one with moderately differentiated lung NET and one with atypical lung carcinoid). There are about 13 cases of NEN breast metastases reported in the English literature. The ileum is the most common primary site, followed by the appendix, duodenum, pancreas and lung.

Conclusion

Breast lesions from extramammary primary often pose a diagnostic challenge, since a breast nodule can be the first and often the only presentation of the disease. However, differentiating between primary and secondary NEN breast lesions is essential, owing to different clinical management and prognosis.

Breast metastasis from medullary thyroid carcinoma mimicking ductal carcinoma with neuroendocrine differentiation

BACKGROUND

Medullary thyroid carcinoma very rarely metastasizes to the breast. Hematogenous spread to the liver, lungs, or mediastinum is more common.

CASE

We describe the morphologic and immunohistochemical features of a 63-year-old woman who presented with a BIRADS-5 category nodule in the right breast and enlarged axillary lymph nodes. Core biopsy showed suggested breast cancer with neuroendocrine or apocrine differentiation. The immunohistochemical profile showed (RE-/RP-/HER-2-) and Ki67 10%. Chromogranin and synaptophysin were positive; AR and GCDFP-15 were negative. On reviewing the patient's clinical history, it was discovered that she had been treated for medullary thyroid carcinoma 15 years earlier. Additional stains showed positivity for TTF-1, CEA, and calcitonin. These findings were consistent with a diagnosis of breast metastasis from medullary thyroid carcinoma. We discuss briefly the morphologic features and the possible key features in order to make an accurate diagnosis.

CONCLUSION

This case highlights the importance of investigating a history of cancer in patients with discordant or unusual histologic or immunohistochemical findings, as this can help avoid misdiagnosis and inappropriate treatment.

Diagnostic Delays in Metastatic Amelanotic Melanoma Presenting as Breast Pain

Patient: Female, 58-year-old

Final Diagnosis: Metastatic amelanotic melanoma

Symptoms: Breast mass • breast pain

Medication: —

Clinical Procedure: Mastectomy

Specialty: Dermatology • Oncology

Review of Nonmammary Metastases to the Breast: Imaging and Clinical Presentation

OBJECTIVES

The purpose of our study is to review the imaging findings of breast metastases from nonmammary sources at our institution and to explore the mode of initial detection of these breast metastases.

METHODS

In this study, we reviewed our electronic medical record and our breast imaging database for all patients who presented with nonmammary metastases to breasts between 5/1/2009 and 12/1/2019. We reviewed all available imaging data, clinical notes, and pathology reports.

RESULTS

Sixteen cases of nonmammary metastases to the breast were included in this study, of which there were 4 (25%) metastases from melanoma, 3 (19%) from carcinoid tumor, 2 (13%) from lung cancer, 2 (13%) from leiomyosarcoma, 1 (6%) each from lipsarcoma, renal cell carcinoma, colon cancer, neuroendocrine tumor, and adenoid cystic carcinoma. 6/8 (75%) lesions that had breast imaging were oval in shape with circumscribed or microlobulated margins on mammography and/or ultrasound. 13/16 (81%) breast metastases were asymptomatic and diagnosed on systemic staging exams. Three out of 16 (19%) nonmammary breast metastases were palpable and were diagnosed on subsequent breast imaging.

CONCLUSIONS

Most (25%) nonmammary breast metastases in our patient population occur from melanoma and most breast metastases (75%) are oval in shape with circumscribed or microlobulated margins. Majority (81%) of these lesions are asymptomatic and initially diagnosed on systemic staging tests, and the remaining are discovered as palpable lesions.

Breast Metastasis From a Non-small Cell Lung Cancer: A Case Report

Although primary breast cancer (BC) is the most frequent cancer in the world, their mammary metastases are rare. In this paper, we report the case of a 51-year-old male patient diagnosed with a mammary lump and an intracranial hypertension syndrome. Mammography showed the presence of an irregular opacity without microcalcifications. After a cytological and immunohistochemical examination, the breast biopsy showed an adenocarcinoma of pulmonary origin. Computed tomography (CT) scans of the cerebrum, cervicothoracic spine, and abdomen showed a right apical pulmonary tumor associated with Barety's lymphadenopathy, as well as the presence of a mass in the right breast and secondary brain lesions. The patient received total brain irradiation which resulted in a marked clinical improvement. Afterward, he was treated with six cycles of palliative chemotherapy based on carboplatin area under the curve (AUC) 6 and paclitaxel, 175 mg/m² every 21 days, with a good response. After two months, the patient presented with a progression and he was treated with second-line chemotherapy. However, after three chemotherapy courses, the disease rapidly progressed and the patient was altered which required his admission to the palliative care department. The patient died 40 days later. This case shows the poor prognostic survival outcomes in this population of patients.

High-Grade Endometrioid Carcinoma of the Endometrium With a GATA-3-Positive/PAX8-Negative Immunophenotype Metastatic to the Breast: A Potential Diagnostic Pitfall

This report describes clinicopathologic findings from the case of a patient with a breast mass that was ultimately diagnosed as a metastatic high-grade endometrioid carcinoma of endometrial origin. The breast lesion as well as the solid areas of the endometrial lesion displayed a similar immunoprofile: GATA3-positive; synaptophysin positive; negative for mammaglobin, gross cystic disease fluid protein-15, chromogranin, estrogen receptor, progesterone receptor, and HER2/neu; and intact expression of the DNA mismatch repair proteins MLH1, MSH2, MSH6, and PMS2. The breast lesion was negative for PAX-8, whereas the solid areas of the endometrial lesion showed focal weak positivity. A review of the literature on GATA-3 expression in endometrial carcinomas found a reported frequency of expression that ranged from 0% to 13% of cases, typically in a patchy, focal, and generally restricted pattern. However, GATA-3 may be diffusely expressed in high-grade endometrial carcinomas. Since the potential for PAX-8 expression to be lost in high-grade endometrioid carcinomas is well known, a GATA-3-positive/PAX8-negative immunoprofile may be encountered in high-grade endometrioid carcinomas of the endometrium, and this composite immunoprofile is a potential diagnostic pitfall when such a lesion is being evaluated in a breast metastasis.

ALK or ROS1-rearranged breast metastasis from lung adenocarcinoma: a report of 2 cases

BACKGROUND

Breast metastases from extramammary sites are extremely rare, with an incidence of 0.4%-1.3% reported in the literature. Insufficient knowledge about its pathology and genetic mutation often leads to misdiagnosis and delayed treatment.

CASE PRESENTATION

We present 2 patients with synchronous (case 1) or metachronous (case 2) breast nodules, revealed as atypical breast metastases from pulmonary adenocarcinomas, in which ALK or ROS1 rearrangement were finally detected in breast mass. After they failed sequential treatments with standard chemotherapies for lung and breast cancer, we reexamined breast lump biopsy and found they were all lung adenocarcinoma metastasis to the breast with the presence of an ALK rearrangement in one case and of ROS1 rearrangement in the other. Eventually these 2 patients were treated with crizotinib. Both the primary tumor and the metastasis of these 2 patients were significantly regressed.

CONCLUSION

Whenever a diagnosis of a suspected tumor with sites at more than one organ is made, pathologic as well molecular pathologic examinations designated for organ-specific cancers should be done.

Breast metastases: A rare manifestation of advanced uterine serous carcinoma

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Metastasis to the breast is a rare, accounting for <1.0% of all breast tumors.

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Over 50% of patient with USC will recur despite multimodality treatment.

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The majority of USC recur locally within the pelvis or abdominal cavity.

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Hematogenous metastasis to the breast has not been reported in USC.

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A new breast mass in a patient with USC is more likely to primary breast cancer.

Metastasis of non-mammary tumors to the breast are uncommon, representing <1% of all breast tumors. Breast metastasis are associated with advanced disease and poor prognosis regardless of the origin of the primary tumor. Uterine cancer metastasis to the breast is an extremely rare finding and has not been reported in the case of serous histology. Here, we review two cases of uterine serous carcinoma metastatic to the breast. Both patients presented with breast-specific complaints including pain and palpable mass and were found to have widely metastatic disease. Tissue biopsy and immunohistochemistry consistent with primary uterine serous carcinoma confirmed the diagnosis of metastasis in both cases. Our findings suggest hematogenous metastasis to the breast is a late phenomenon in the course of endometrial carcinoma and associated with the development of disease at multiple sites. This emphasizes the importance of complete evaluation in patients presenting with breast complaints and known history of malignancy, as this may be the only presenting symptoms in patients with widely metastatic disease.

Bilateral Breast Metastases from Epstein-Barr Virus-Associated Gastric Cancer during Pregnancy: Is There a Method to Its Madness?

Breast metastases of extramammary malignant neoplasms are rare, with an incidence of 0.3%-2.7% among all malignant mammary tumors. Breast metastases from gastric carcinoma are very rare (<0.1%), and this event is even rarer during pregnancy. Herein, we describe a 39-year-old Caucasian woman with a history of an Epstein-Barr virus-associated gastric carcinoma (EBVaGC) that was characterized by prominent tumor infiltrating lymphocytes. Three years after undergoing radical surgery, the patient developed bilateral breast nodules during her pregnancy. A breast biopsy was performed, and histology confirmed a diagnosis of EBVaGC; tumor cells showed positivity for cytokeratin 8/18 and E-cadherin, and negativity for cytokeratin 7, cytokeratin 20, cytokeratin 5/6, caudal type homebox 2, androgen receptor, mammaglobin, gross cystic disease fluid protein-15, and estrogen and progesterone receptors. We also discuss the main diagnostic pitfalls. To our knowledge, this is the first report of an EBVaGC with lymphoid stroma that developed breast metastases during pregnancy.

Breast metastasis from rectal cancer with BRAF V600E mutation: a case report with a review of the literature

Metastasis of rectal cancer to the breast is an extremely rare clinical event. We report the case of a 67-year-old woman with a metastatic breast tumor derived from a BRAF V600E mutant rectal carcinoma that was diagnosed and resected curatively 1 year previously. Computed tomography showed a left breast mass and multiple lung nodules suspected to be indicative of recurrent rectal cancer. The ultrasonography examination demonstrated a 10 × 10-mm hypoechoic solid lesion in the left breast with an elevation in the serum carcinoembryonic antigen level and serum carbohydrate antigen 19-9 level. Core needle biopsy was performed, and histopathologic examination showed Cytokeratin 20 and CDX-2 positivity, compatible with rectal cancer. To our knowledge, this is the first case of a metastatic breast tumor arising from rectal carcinoma with BRAF mutation. Although breast metastasis is very rare event, the possibility of breast metastasis from extra mammary sites should be considered when the breast tumor is found in cancer treatment.