Gross cystic disease fluid protein-(GCDFP-15): expression in primary lung adenocarcinoma

Gross Cystic Disease Fluid Protein-15 (GCDFP-15) Expression Characterizes Breast Mucinous Carcinomas in Older Women

The predominant histological subtype of breast mucinous carcinoma in older women is type B (hypercellular type), and, in younger women, it is type A (hypocellular type). The characteristics of mucinous carcinomas of the same histological subtype may differ between older and younger women. This study aims to systematically clarify the pathological/immunohistochemical features of mucinous carcinomas. A total of 21 surgical cases of mucinous carcinoma (type A/B: 9/12 cases) in the older group (≥65 years) and 16 cases (type A/B: 14/2 cases) in the younger group (≤55 years) (n = 37) were included. Gross cystic disease fluid protein-15 (GCDFP-15) and eight other markers were used for immunostaining. The GCDFP-15-positive rate in the older group was high regardless of the histological subtype (type A, 77.8%; type B, 91.7%). The GCDFP-15 positivity in the older group was significantly higher than that in the younger group (p < 0.001 for Allred score). Among type A, GCDFP-15 positivity was significantly higher in the older group than in the younger group (p = 0.042 for the Allred score and p = 0.007 for the positivity rate). The present results suggest that GCDFP-15 expression characterizes mucinous carcinomas in older women.

Avoiding "False Positive" and "False Negative" Immunohistochemical Results in Breast Pathology

Immunohistochemistry (IHC) plays an important role in the evaluation of breast pathology specimens to provide both diagnostic and prognostic/therapeutic information. Although most IHCs used in breast pathology can be easily interpreted, pitfalls do exist, especially in some uncommon scenarios. This review intends to focus on the challenging areas such as the interpretation of myoepithelial cell markers in differentiating benign proliferation and in situ carcinoma from invasive carcinoma, lobular cell markers in differentiating lobular from ductal carcinoma, cytokeratin and other markers in diagnosing metaplastic carcinoma, and breast tissue origin markers in diagnosing breast primary carcinoma. The challenges in interpreting prognostic and predictive markers will be also discussed.

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.

SOX10, GATA3, GCDFP15, Androgen Receptor, and Mammaglobin for the Differential Diagnosis Between Triple-negative Breast Cancer and TTF1-negative Lung Adenocarcinoma

Triple-negative breast cancer (TNBC) patients have an increased risk of developing visceral metastases and other primary nonbreast cancers, particularly lung cancer. The differential diagnosis of TNBC metastases and primary cancers from other organs can be difficult due to lack of a TNBC standard immunoprofile. We analyzed the diagnostic value of estrogen receptor, progesterone receptor, human epidermal growth factor receptor, thyroid transcription factor-1 (TTF1), Napsin A, mammaglobin, gross cystic disease fluid protein 15 (GCDFP15), Sry-related HMg-Box gene 10 (SOX10), GATA-binding protein 3 (GATA3), and androgen receptor in a series of 207 TNBC and 152 primary lung adenocarcinomas (LA). All tested TNBCs were TTF1 and Napsin A-negative. When comparing TNBC and TTF1-positive or negative LA, SOX10 had the best sensitivity (62.3%) and specificity (100%) as a marker in favor of TNBC compared with LA, irrespective of TTF1 status (P<0.0001). GATA3 had moderate sensitivity (30.4%) and excellent specificity (98.7%) and misclassified only 2/152 LA (1.3%). GCDFP15 had a moderate sensitivity (20.8%) and excellent specificity (98%) and misclassified only 3/152 (2%) LA. Mammaglobin and androgen receptor had moderate sensitivities (38.2% and 30%), good specificities (81.6% and 86%), and misclassified 28/152 and 21/152 LAs, respectively. In multivariate analysis, the best markers, enabling the distinction between SOX10-negative TNBC and TTF1 and Napsin A-negative LA were GATA3 (odds ratio=33.5; 95% confidence interval, 7.3-153.5; P<0.0001) and GCDFP15 (odds ratio=31.7; 95% confidence interval, 6.9-145.6; P<0.0001). Only 13/207 (6.3%) TNBC cases did not express any aforementioned marker. On the basis of our results, the best sequential immunohistochemical analysis to differentiate TNBC from TTF1-negative LA is first SOX10 followed by GATA3, and finally GCDFP15. This order is important in the diagnostic workup of small biopsies from lung nodules in women with a previous history of TNBC.

Immunohistochemistry for diagnosis and prognosis of breast cancer: a review

Breast cancer is the most prevalent malignant tumor and main oncologic cause of mortality in women. Although most diagnosis of breast pathology is accomplished using hematoxylin and eosin stained sections, some cases require immunohistochemistry for proper evaluation. We investigated the latter cases including distinctions between ductal and lobular carcinoma, in situ and invasive carcinoma, typical ductal hyperplasia and atypical ductal hyperplasia/ductal carcinoma in situ, papillary and spindle cell lesion assessment, metastasis evaluation, and assessment of prognostic and therapy markers. E-cadherin is used to differentiate ductal and lobular carcinoma; 34βE12, CK8, p120 catenin and β-catenin also produce consistent results. Myoepithelial cell (MEC) stains are used to evaluate in situ and invasive carcinoma; calponin, smooth muscle myosin heavy chain and p63 are sensitive/specific markers. 34βE12 and CK5/6 are positive in ductal hyperplasia, which enables its differentiation from atypical ductal hyperplasia and ductal carcinoma in situ. CK 5/6, ER and MEC markers are consistent options for evaluating papillary lesions. Spindle cell lesions can be assessed using β-catenin, SMA, CD34, p63, CKs and hormone receptors. It is important to differentiate primary carcinomas from metastases; the most commonly used markers to identify breast origin include mammaglobin, GCDFP-15, GATA3 and ER, although none of these is completely sensitive or specific. Immunohistochemistry can be used to evaluate central prognostic and predictive factors including molecular subtypes, HER2, hormone receptors, proliferation markers (Ki-67) and lymph-vascular invasion markers including ERG, CD31, CD34, factor VIII and podoplanin. Owing to the complexity of mammary lesions, diagnosis also depends on each particular situation, evaluation of cytological characteristics revealed by immunochemistry and correlation with histological findings.

Pathologic differential diagnosis of metastatic carcinoma in the liver

The liver is one of the most common sites to which malignancies preferentially metastasize. Although a substantial number of liver malignancies are primary tumors, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, the metastasis of carcinomas to the liver is relatively common and frequently encountered in clinical settings. Representative carcinomas that frequently metastasize to the liver include colorectal carcinoma, breast carcinoma, neuroendocrine tumors, lung carcinoma, and gastric carcinoma. The diagnostic confirmation of suspected metastatic lesions in the liver is generally achieved through a histopathologic examination of biopsy tissues. Although morphology is the most important feature for a pathologic differential diagnosis of metastatic carcinomas, immunohistochemical studies facilitate the differentiation of metastatic carcinoma origins and subtypes. Useful immunohistochemical markers for the differential diagnosis of metastatic carcinomas in the liver include cytokeratins (CK7, CK19, and CK20), neuroendocrine markers (CD56, synaptophysin, and chromogranin A), and tissue-specific markers (CDX2, SATB2, TTF-1, GCDFP-15, mammaglobin, etc.). Here, we provide a brief review about the pathologic differential diagnosis of major metastatic carcinomas in the liver.

Best Practices Recommendations for Diagnostic Immunohistochemistry in Lung Cancer

Since the 2015 WHO classification was introduced into clinical practice, immunohistochemistry (IHC) has figured prominently in lung cancer diagnosis. In addition to distinction of small cell versus non-small cell carcinoma, patients' treatment of choice is directly linked to histologic subtypes of non-small cell carcinoma, which pertains to IHC results, particularly for poorly differentiated tumors. The use of IHC has improved diagnostic accuracy in the classification of lung carcinoma, but the interpretation of IHC results remains challenging in some instances. Also, pathologists must be aware of many interpretation pitfalls, and the use of IHC should be efficient to spare the tissue for molecular testing. The International Association for the Study of Lung Cancer Pathology Committee received questions on practical application and interpretation of IHC in lung cancer diagnosis. After discussions in several International Association for the Study of Lung Cancer Pathology Committee meetings, the issues and caveats were summarized in terms of 11 key questions covering common and important diagnostic situations in a daily clinical practice with some relevant challenging queries. The questions cover topics such as the best IHC markers for distinguishing NSCLC subtypes, differences in thyroid transcription factor 1 clones, and the utility of IHC in diagnosing uncommon subtypes of lung cancer and distinguishing primary from metastatic tumors. This article provides answers and explanations for the key questions about the use of IHC in diagnosis of lung carcinoma, representing viewpoints of experts in thoracic pathology that should assist the community in the appropriate use of IHC in diagnostic pathology.

Breast metastasis from EGFR-mutated lung adenocarcinoma: A case report and review of the literature

Although lung cancer rarely metastasizes to the breast, we report a case of breast metastasis from lung adenocarcinoma harboring an epidermal growth factor receptor mutation. This breast metastasis was initially considered recurrent breast cancer and was later diagnosed based on histopathological and molecular examinations as metastasis from lung cancer.

Primary Small Cell Carcinoma Of Lung With Metachronous Breast Metastasis

Breast metastases from an extra-mammary malignancy are rare. Among the lung malignancies that metastasise in the breasts, previous literature has described approximately 30 cases of NSCLC and only a few cases of SCLC. Here, we present a 54-year-old woman with metachronous breast metastasis from pulmonary small cell carcinoma. She presented with a soft tissue mass in the right lung hilum. After bronchoscopy with biopsy, SCLC was verified. Th e patient was given 4 cycles of etoposide and cisplatin followed by radiation therapy. Seven months after the diagnosis of primary lung cancer, the patient palpated a mass in her right breast. Clinical examination and further diagnostics revealed the suspected malignancy, and a radical mastectomy was performed. Immunohistochemical findings suggested metastatic SCLC in the breast. Differentiation between primary and metastatic cancer in the breast is very important for therapeutic planning

Markers of metastatic carcinoma of breast origin

This review summarizes the three major breast-associated markers that can be of assistance in evaluating metastatic carcinomas for which a breast primary diagnosis is entertained. These markers include gross cystic disease fluid protein-15 (GCDFP-15), mammaglobin, and GATA3. The first two are cytoplasmic markers that show comparable sensitivities for breast cancer, although relatively few of the published studies have employed the same antibodies against the target molecule, making direct comparisons challenging. GATA3 is a nuclear transcription factor that shows superior sensitivity to GCDFP-15 and mammaglobin. However, the specificity of GATA3 can pose challenges, inasmuch as carcinomas of the bladder and other sites can show significant levels of positivity. Determination of the optimal panel of antibodies employed in a given clinical setting will thus depend on the non-breast tumours included in the differential diagnosis.

Immunohistochemical profile of breast cancer with respect to estrogen receptor and HER2 status

There are a few studies that have evaluated a panel of stains on a single large data set of breast cancers, which is required for direct comparison between antibodies. The immunohistochemical panel in this study was chosen to include breast-specific markers and markers that are expressed in tumors resembling breast cancer. The individual marker positivity in decreasing order was 95% (177/186) for GATA-3, 92% (172/186) for cytokeratin (CK)7, 80% (151/189) for AR, 80% for estrogen receptor (158/198), 69% for progesterone receptor (137/198), 55% (105/190) for NY-BR-1, 52% (99/189) for mammaglobin, 31% (59/191) for vimentin, 26% (51/195) for GCDFP-15, 0.5% (1/186) for CK20, and 0% (0/188) for PAX-8. When tumors were categorized based on estrogen receptor and HER2 status; a total of 45 profiles were identified. In addition, some tumors showed an unconventional profile-although the majority of breast carcinomas were CK7-positive/CK20-negative, a CK7-negative/CK20-negative profile was seen in ∼8% of the cases. Such a profile can create confusion in investigation of a carcinoma of unknown origin. The results define the individual sensitivity of each marker and establish a baseline diagnostic profile of breast cancer in a large data set. In addition, the results support the use of immunohistochemical panel for confirming or determining breast as the source of metastasis.

Practical Applications in Immunohistochemistry: Carcinomas of Unknown Primary Site

CONTEXT

-Identification of the site of origin of carcinoma of unknown primary using immunohistochemistry is a frequent requirement of anatomic pathologists. Diagnostic accuracy is crucial, particularly in the current era of targeted therapies and smaller sample sizes.

OBJECTIVES

-To provide practical guidance and suggestions for classifying carcinoma of unknown primary using both proven and new antibodies, as well as targeting panels based on integration of morphologic and clinical features.

DATA SOURCES

-Literature review, the authors' practice experience, and authors' research.

CONCLUSIONS

-With well-performed and interpreted immunohistochemistry panels, anatomic pathologists can successfully identify the site of origin of carcinoma of unknown primary. It is crucial to understand not only the diagnostic uses of the many available antibodies but also the potential limits and pitfalls.

Differential expression of immunohistochemical markers in primary lung and breast cancers enriched for triple-negative tumours

AIMS

In breast cancer patients presenting with a lung lesion, the distinction between lung and breast origin is clinically important. Lung and breast cancers are both CK7(+) /CK20(-) , so additional immunohistochemical markers are needed.

METHODS AND RESULTS

We examined the expression of oestrogen receptor (ER), progesterone receptor (PR), thyroid transcription factor-1 (TTF-1), gross cystic disease fluid protein-15 (GCDFP-15), p63 and Wilms' tumour 1 (WT1) in a series of tissue microarrays comprising 266 non-small-cell lung cancers and 837 primary breast cancers enriched for triple-negative tumours (TNBC). Staining for ER, PR, TTF-1 and GCDFP-15 was present in 63%, 49%, 0% and 25% of breast and 6%, 9%, 59% and 1% of lung cancers, respectively. Strong staining for p63 was present in 63 (97%) lung squamous cell carcinomas and only eight (9%) TNBC. WT1 nuclear staining was rare; however, cytoplasmic staining was identified in 49 (40%) TNBC and 10 (5%) lung cancers. Cluster analysis segregated TNBC from lung cancers with TTF-1 and/or p63 staining favouring lung origin, and GCDFP-15 or WT1 staining favouring breast origin. Cancers negative for all four markers (17%) were 60% breast and 40% lung origin.

CONCLUSION

An immunohistochemical panel incorporating ER, TTF-1, GCDFP-15, p63 and WT1 can help to distinguish lung cancer from metastatic breast cancer, including TNBC.

Metastatic carcinoma of unknown primary: diagnostic approach using immunohistochemistry

Carcinoma of unknown primary origin (CUP) is one of the 10 most prevalent malignancies. CUP patients in whom a site of origin can be ascribed have better outcomes than those in which the primary tumor remains unidentified. Among the tools available to pathologists in approaching these lesions, immunohistochemistry is a reliable, inexpensive, and widely available resource. New markers continue to emerge, which, in combination with other historically useful antibodies, allow rapid and accurate identification of primary site in an increasing number of cases. This review discusses the approach to the diagnosis of CUP using immunohistochemistry and outlines some of the most useful markers with a particular focus on the utility of lineage-restricted transcription factors, including CDX2, NKX3-1, PAX8, SATB2, TTF-1, and SF1.

Gross cystic disease fluid protein 15 in stratum corneum is a potential marker of decreased eccrine sweating for atopic dermatitis

It is well known that eccrine sweating is attenuated in patients with atopic dermatitis (AD). We have reported by using proteome analysis that gross cystic disease fluid protein 15 (GCDFP15), a substance secreted from eccrine sweat glands, is decreased in tape-stripped stratum corneum (SC) samples from AD patients. The aim of this study was to evaluate GCDFP15 production by eccrine glands with SC samples and to assess sweating in AD. SC samples were obtained from 51 healthy control (HC) and 51 AD individuals. Sweat samples were from 18 HC and 12 AD subjects. GCDFP15 was quantified by ELISA. By immunohistochemistry, the expression of GCDFP15 in eccrine glands was examined in normal and AD skin specimens. To identify GCDFP15-producing cells, double immunofluorescence staining for GCDFP15 and S100 protein was performed in frozen sections. To address the mechanism underlying the decreased eccrine sweating in AD patients, we examined the expression of cholinergic receptor M3 (CHRM3), a receptor for acetylcholine-induced sweating, in eccrine sweat glands. The amounts of GCDFP15 in the SC extracts were significantly lower in AD than HC (P < 0.0001). The sweat samples from AD patients also had lower levels of GCDFP15 concentration (P < 0.05). Immunohistochemistry showed positive GCDFP15 staining in the eccrine gland secretory cells and the ductal and acrosyringial lumen in normal skin, but AD lacked clear staining. Immunofluorescence staining revealed that GCDFP15 was co-expressed with S100 protein, suggesting that the clear cell of eccrine glands produces GCDFP15. Finally, we found that the expression of CHRM3 was depressed in AD, suggesting contribution to the low sweating. The SC of AD patients contains a low amount of GCDFP15 due to both low sweating and low GCDFP15 concentration in the sweat. GCDFP15 in SC is a potential marker for dysregulated sweating in AD.

A comparative immunohistochemistry study of diagnostic tools in salivary gland tumors: usefulness of mammaglobin, gross cystic disease fluid protein 15, and p63 cytoplasmic staining for the diagnosis of mammary analog secretory carcinoma?

BACKGROUND

Mammary analog secretory carcinoma (MASC) of the salivary gland has been recently described according to morphological, immunohistochemical, and molecular (ETV6-NTRK3 translocation) similarities with the mammary secretory carcinoma. The most important differential diagnostic considerations of MASC are low-grade adenocarcinoma not otherwise specified (NOS), cystadenocarcinoma, and acinic cell carcinoma (AciCC). These tumors may share an overlapping morphology with MASC, and additional immunohistochemical studies are required to reinforce the diagnosis. Mammaglobin, GCDFP-15, and p63 staining have been reported in MASC. Our study was designed to check the specificity of these antibodies in MASC compared to other frequent tumors of salivary glands.

METHODS

A series of 62 salivary gland tumors [10 MASCs, 5 adenocarcinomas NOS and 2 cystadenocarcinomas with MASC features and without ETV6 rearrangement, one low-grade cribriform cystadenocarcinoma (LGCCC), 9 AciCCs, 10 MECs, 10 adenoid cystic carcinomas (AdeCCs), 5 polymorphous low-grade adenocarcinomas (PLGAs), and 10 pleomorphic adenomas (PAs)] was analyzed by immunohistochemistry with mammaglobin, GCDFP-15, and p63 antibodies.

RESULTS

Positivity for mammaglobin was observed in all MASCs, cystadenocarcinomas, LGCCC, and PLGAs, in some adenocarcinomas NOS, PAs, and MECs, rarely in AciCCs and never in AdeCCs. Positivity for GCDFP-15 was observed in most of the tumor types except in AdeCCs. Interestingly, cytoplasmic positivity for p63 was observed in most of MASCs and PLGAs while rarely in adenocarcinomas NOS and PAs, and never in the other tumor types.

CONCLUSION

Our study revealed the usefulness of mammaglobin and p63 cytoplasmic staining to define which tumors are worth to be screened for ETV6 rearrangement.

Utility of GATA3, mammaglobin, GCDFP-15, and ER in the detection of intrathoracic metastatic breast carcinoma

INTRODUCTION

Breast carcinoma (BC) metastatic to the intrathoracic cavity is difficult to diagnose due to low sensitivity of current immunohistochemical (IHC) stains. Mammaglobin, gross cystic disease fluid protein-15 (GCDFP-15), and estrogen receptor (ER) immunomarkers show variable results. GATA3 is a recently described marker for detecting urothelial and breast cancers. Our goal is to test the utility of GATA3 in cell blocks from thoracic cytology specimens.

MATERIALS AND METHODS

We retrieved cases of BC that metastasized to the thoracic cavity from January 1, 2005 to September 30, 2013. IHC was performed on the cell blocks for the presence of GATA3, ER, GCDFP-15, and mammaglobin. Stains were scored quantitatively and qualitatively.

RESULTS

Fifty cases of metastatic BC found in pleural effusions and endobronchial ultrasound-guided fine-needle aspirates were identified in 48 patients. Thirty-four cases had sufficient material for IHC (19 pleural effusions, 15 endobronchial ultrasound-guided fine-needle aspirates). GATA3 showed strong nuclear positivity in 31 of 34 cases (91.2%). ER (25 of 34, 73.5%), mammaglobin (23 of 34, 67.6%) and GCDFP-15 (11 of 34, 32.6%) were positive in fewer cases. GATA3 and ER were concordant in 26 of 34 cases (76.5%) (24 ER/GATA3-positive, 2 ER/GATA3-negative). Discordant results were found in 8 of 34 cases (23.5%). Of these, GATA3 was positive and ER was negative in 7 cases. GATA3 was negative and ER was positive in 1 case.

CONCLUSIONS

GATA3 is more sensitive than ER, mammaglobin, or GCDFP-15 in detecting metastatic BC in cytologic specimens. GATA3 may be positive when ER is negative. In cytologic specimens with limited diagnostic material, GATA3 may be used as a first-line marker in a limited IHC panel to support metastatic BC.

Breast metastasis from lung cancer: a report of two cases and literature review

Breast metastasis from extra-mammary malignancy is rare. An incidence of 0.4% to 1.3% has been reported in literature. The primary malignancies that most commonly metastasize to the breast are leukemia, lymphoma, and malignant melanoma. In this report, two cases of pulmonary metastasis to the breast were presented. A 40-year-old female manifested a right breast mass of 2-month duration. After physical examination was performed, a poorly defined mass was noted in the upper outer quadrant of the right breast. Another 49-year-old female manifested right breast mass of 5-day duration. A poorly defined mass was noted in the lower inner quadrant of the right breast. Mammography results also revealed breast cancer. The patients underwent local excision. After histological and immunohistochemical analyses were conducted, a primary lung carcinoma that metastasized to the breast was diagnosed. An accurate differentiation of metastasis to the breast from primary breast cancer is very important because the treatment and prognosis of the two differ significantly.

Diagnostic utility of immunohistochemistry in distinguishing between epithelioid pleural mesotheliomas and breast carcinomas: a comparative study

Epithelioid mesotheliomas and breast carcinomas can present a variety of morphologic patterns. Because of this, breast carcinomas that metastasize to the pleura and lung may be confused with mesotheliomas. The aim of the present study is to compare the immunohistochemical markers currently available for the diagnosis of these 2 malignancies and to determine the best panel of markers that can be used to assist in discriminating between them. Sixty epithelioid mesotheliomas and 80 breast carcinomas (40 triple negative and 40 estrogen receptor positive) were investigated for expression of the positive mesothelioma markers calretinin, keratin 5/6, mesothelin, podoplanin, thrombomodulin, and WT1; the positive carcinoma marker claudin 4; and the breast-associated markers gross cystic disease fluid protein 15 (GCDFP-15), mammaglobin, and GATA3. All of the epithelioid mesotheliomas reacted for calretinin and keratin 5/6, 93% for WT1; 88% for podoplanin; 77% for thrombomodulin; 23% for GATA3; and 0% for claudin 4, GCDFP-15, and mammaglobin, respectively. Of the triple-negative breast carcinomas, 100% expressed claudin 4; 5%, keratin 5/6; 30%, GATA3; 18%, mammaglobin; 15%, GCDFP-15; 56%, mesothelin; 38%, calretinin; 18%, thrombomodulin; 5%, WT1; and 3%, podoplanin. Among the estrogen receptor-positive breast carcinomas, 100% were claudin 4 and GATA3 positive; 70% expressed GCDFP-15; 63%, mammaglobin; 13%, calretinin; 13%, thrombomodulin; 8%, WT1; 5%, keratin 5/6; 3%, mesothelin; and 0%, podoplanin. It is concluded that podoplanin and WT1 are the best positive mesothelioma markers for differentiating epithelioid mesotheliomas from breast carcinomas. An accurate differential diagnosis can be reached with the use of these two markers in combination with the breast-associated markers GCDFP-15, mammaglobin, and GATA3.

Diagnostic role of immunohistochemistry in the evaluation of breast pathology specimens

CONTEXT

Immunohistochemistry plays a vital role in the evaluation of breast pathology specimens.

OBJECTIVE

To discuss the role of myoepithelial cell markers in the evaluation of various breast lesions. Other markers, such as E-cadherin and those used to differentiate mammary carcinoma from metastatic tumors to the breast, and markers used in the differential diagnosis of Paget disease, are also discussed.

DATA SOURCES

Data were obtained from review of the pertinent peer-reviewed literature.

CONCLUSIONS

Myoepithelial cell markers vary in their sensitivity and specificity, and one should be aware of the potential pitfalls in interpretation. Using panels of 2 or more myoepithelial cell markers is always recommended, either singly or in cocktail forms. Although negative E-cadherin staining supports the diagnosis of lobular origin, positive staining does not rule it out. Immunohistochemistry can be helpful in differentiating Paget disease from its mimics. Although metastatic tumors to the breast are rare, a triple-negative immunophenotype and absence of an in situ component should be a "red flag" for such possibility, especially in patients with clinical history of an extramammary malignancy.

Breast metastasis from a pulmonary adenocarcinoma: Case report and review of the literature

Breast metastasis from extra-mammary malignancy is rare. An incidence of 0.4-1.3% has been reported in the literature. The primary malignancies most commonly metastasizing to the breast are leukemia, lymphoma and malignant melanoma. We present a case of metastasis to the breast from a pulmonary adenocarcinoma, diagnosed concomitantly with the primary tumor. A 43-year-old female presented with dyspnea and a dry cough of 3 weeks' duration. A subsequent chest radiograph revealed a massive pleural effusion. Additionally, on physical examination, a poorly defined mass was noted in the upper outer quadrant of the right breast. The patient underwent bronchoscopy, simple right mastectomy and medical thoracoscopy. Following cytology, histology and immunohistochemistry, primary lung adenocarcinoma with metastasis to the breast and parietal pleura was diagnosed. Histologically, both the primary and metastatic anatomic sites demonstrated a micropapillary component, which has recently been recognized as an important prognostic factor. Although the patient received chemotherapy, she succumbed to her condition within 8 months. Accurate differentiation of metastasis from primary carcinoma is very important as the treatment and prognosis of the two differ significantly.

Application of immunohistochemistry in the diagnosis of epithelioid mesothelioma: a review and update

A large number of immunohistochemical markers that can assist in the differential diagnosis of epithelioid mesotheliomas are currently available. Because these markers are expressed differently in the various types of carcinomas that can metastasize to the serosal membranes and can potentially be confused with epithelioid mesothelioma, their selection for inclusion in a diagnostic panel largely depends on the differential diagnosis, as well as on which ones work the best in a given laboratory. Traditionally, the panels used in the differential diagnosis of epithelioid mesothelioma have consisted of a combination of positive mesothelioma markers and broad-spectrum carcinoma markers. At present, a wide variety of organ-associated carcinoma markers such as thyroid transcription factor-1 and napsin A for the lung, PAX 8 and PAX 2 for the kidney, and Müllerian-derived tumors; gross cystic disease fluid protein-15 and mammaglobin for the breast; and CDX2 for intestinal differentiation are available, which can assist in establishing the site of origin of an adenocarcinoma when included in a diagnostic panel. This article provides updated information on the composition of the panels of markers recommended in the various differential diagnoses.

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.

Gene expression signatures differentiate adenocarcinoma of lung and breast origin in effusions

Lung and breast adenocarcinoma at advanced stages commonly involve the serosal cavities, giving rise to malignant effusions. The aim of the present study was to compare the global gene expression patterns of metastases from these 2 malignancies, to expand and improve the diagnostic panel of biomarkers currently available for their differential diagnosis, as well as to define type-specific biological targets. Gene expression profiles of 7 breast and 4 lung adenocarcinoma effusions were analyzed using the HumanRef-8 BeadChip from Illumina. Differentially expressed candidate genes were validated using quantitative real-time polymerase chain reaction and immunohistochemistry. Unsupervised hierarchical clustering using all 54,675 genes in the array separated lung from breast adenocarcinoma samples. We identified 289 unique probes that were significantly differentially expressed in the 2 cancers by greater than 2-fold using moderated t statistics, of which 65 and 224 were overexpressed in breast and lung adenocarcinoma, respectively. Genes overexpressed in breast adenocarcinoma included TFF1, TFF3, FOXA1, CA12, PITX1, RARRES1, CITED4, MYC, TFAP2A, EFHD1, TOB1, SPDEF, FASN, and TH. Genes overexpressed in lung adenocarcinoma included TITF1, SFTPG, MMP7, EVA1, GPR116, HOP, SCGB3A2, and MET. The differential expression of 15 genes was validated by quantitative real-time PCR, and differences in 8 gene products were confirmed by immunohistochemistry. Expression profiling distinguishes breast adenocarcinoma from lung adenocarcinoma and identifies genes that are differentially expressed in these 2 tumor types. The molecular signatures unique to these cancers may facilitate their differential diagnosis and may provide a molecular basis for therapeutic target discovery.

NY-BR-1 and PAX8 immunoreactivity in breast, gynecologic tract, and other CK7+ carcinomas: potential use for determining site of origin

The distinction between breast and müllerian carcinomas from each other and from tumors with a similar cytokeratin profile can be difficult. We tested the usefulness of 2 new markers, NY-BR-1 and PAX8, by staining a variety of breast and gynecologic carcinomas, along with tumors of pancreas, bile ducts, stomach, and gastroesophageal junction. NY-BR-1 expression (ie, H score >10) was seen in 58.4% of breast carcinomas (111/190), 5.6% of müllerian carcinomas (8/142), 7% of pancreatic tumors (1/15), 0% of cholangiocarcinomas (0/22), 0% of gastric tumors (0/36), and 0% of gastroesophageal carcinomas (0/25). All 188 breast carcinomas were negative for PAX8. PAX8 expression was seen in 72.4% of müllerian tumors (105/145). All pancreatic tumors (n = 15), cholangiocarcinomas (n = 23), and gastric (n = 35) and gastroesophageal junction (n = 25) carcinomas were negative for PAX8. Addition of NY-BR-1 and PAX8 in a panel would be useful in distinguishing breast cancer, gynecologic tumors, and tumors of the upper gastrointestinal tract.

Metastasis to the breast from an adenocarcinoma of the lung with extensive micropapillary component: a case report and review of the literature

Breast metastasis from extra-mammary malignancy is rare. Based on the literature an incidence of 0.4-1.3% is reported. The primary malignancies most commonly metastasizing to the breast are leukemia-lymphoma, and malignant melanoma. We present a case of metastasis to the breast from a pulmonary adenocarcinoma, with extensive micropapillary component, diagnosed concomitantly with the primary tumor. A 73-year-old female presented with dyspnea and dry cough of 4 weeks duration and a massive pleural effusion was found on a chest radiograph. Additionally, on physical examination a poorly defined mass was noted in the upper outer quadrant of the left breast. The patient underwent bronchoscopy, excisional breast biopsy and medical thoracoscopy. By cytology, histology and immunohistochemistry primary lung adenocarcinoma with metastasis to the breast and parietal pleura was diagnosed. Both the primary and metastatic anatomic sites demonstrated histologically extensive micropapillary component, which is recently recognized as an important prognostic factor. The patient received chemotherapy but passed away within 7 months. Accurate differentiation of metastatic from primary carcinoma is of crucial importance because the treatment and prognosis differ significantly.

A study of immunohistochemical differential expression in pulmonary and mammary carcinomas

The risk of developing a second primary cancer is increased in patients with breast cancer, and the lung is one of the major sites involved. Moreover, the lung is the major metastatic site for breast cancers. A distinction between metastatic breast cancer and primary lung cancer can be histologically difficult, and both show an overlapping CK7+/CK20- immunoprofile in a majority of cases. The degree of difficulty increases with poorly differentiated tumors. We investigated differential expressions of TTF-1, Napsin A, surfactant apoprotein A, estrogen receptor, GATA-3, mammaglobin, and GCDFP-15 immunostains in 197 pulmonary carcinomas (158 adenocarcinomas, 39 squamous) and 115 invasive mammary carcinomas (91 ductal, 24 lobular type). In mammary carcinomas, estrogen receptor, GATA-3, mammaglobin, and GCDFP-15 were expressed in 74, 72, 64, and 62%, respectively, whereas TTF-1, Napsin A, and surfactant apoprotein A were all negative. The expressions were diffuse in estrogen receptor and GATA-3, and variable in mammaglobin and GCDFP-15. For a combination of estrogen receptor/mammaglobin or GATA-3/mammaglobin, 83% of mammary carcinomas were positive, and the detection rate was not improved by using all three markers. All lung squamous cell carcinomas were negative for all markers studied. TTF-1, Napsin A, and surfactant apoprotein A were positive in 80, 77, and 45% of pulmonary adenocarcinomas. None of the TTF-1-negative tumors expressed surfactant apoprotein A. GCDFP-15 was focally expressed in 2.5% of pulmonary adenocarcinomas, and estrogen receptor was focally expressed in one case (1.2%) of pulmonary adenocarcinoma. When metastasis from breast cancer is suspected in the lung, a combination of either estrogen receptor/mammaglobin or GATA-3/mammaglobin as breast markers, and a combination of TTF-1 and Napsin A as lung markers may be helpful for differentiating between the two. Caution should be taken in the interpretation of GCDFP-15 due to its occasional expression in pulmonary adenocarcinomas.

Bibliography. Current world literature

This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 November 2007 and 31 October 2008 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.

Micropapillary lung adenocarcinoma: EGFR, K-ras, and BRAF mutational profile

Micropapillary lung adenocarcinoma (MPA) has been reported as an aggressive variant of adenocarcinoma, frequently manifesting at high stage with a poor prognosis. We analyzed the clinical and molecular profile of 15 primary MPAs for K-ras, EGFR, and BRAF mutations and performed fluorescence in situ hybridization for EGFR amplification. In our study, 11 (73%) of 15 MPAs harbored mutually exclusive mutations: 5 (33%) K-ras, 3 (20%) EGFR, and 3 (20%) BRAF. Mutations in all 3 genes occurred in patients with a smoking history and tumors with mucinous differentiation and secondary lepidic, acinar, and solid growth, suggesting that in a Western population, cytomorphologic correlation with genetic mutations is more unpredictable than in Japanese cohorts. We conclude that K-ras, EGFR, and BRAF mutations are disproportionately seen in adenocarcinomas of lung with a dominant micropapillary growth pattern compared with conventional adenocarcinoma in our institutional experience.

Peripheral squamous cell carcinoma of lung: patterns of growth with particular focus on airspace filling

Because the clinical behavior of low-stage adenocarcinomas of the lung is best predicted when adjusted for the presence of a lepidic growth pattern, we studied the marginal growth patterns of 62 peripheral squamous cell carcinomas of lung focusing on the patterns of marginal/peripheral growth and presence of an alveolar filling component. Approximately one fourth of squamous carcinomas had 20% of their gross diameters composed of carcinoma cells filling airspaces with preserved alveolar architecture, and 26% of these cases had their gross size downgraded from a T2 to a T1 lesion. Despite this size recalculation, insufficient numbers of cases made it impossible to determine if this change had independent prognostic significance for T1/T2N0 lesions. Nonetheless, such a growth pattern was common and should be studied further in larger series to determine if an airspace filling growth pattern in squamous carcinoma is clinically important.