Breast Cancer Subtypes in Northern Thailand and Barriers to satisfactory survival outcomes.

BACKGROUND: The incidence of breast cancer (BC) in Thailand has been rising at an alarming rate. The annual incidence of BC in Thailand has doubled over a span of 15 years. A retrospective study was conducted with the primary objective of assessing and comparing survival rates of patients with BC, stratified by subtype of BC. METHODS: A retrospective study was implemented for a cohort of women receiving a diagnosis of invasive BC with the objective of assessing and comparing their overall survival, stratified by BC subtype. Thai women receiving a diagnosis of their first primary invasive BC between January 2006 and December 2015 at Chiang Mai University Hospital were studied with 3,150 cases meeting the eligible criteria. RESULTS: The median follow-up time was 4.9 years (Inter Quartile Range: 2.8-7.7). The most common diagnosed subtype was luminal B-like (n = 1,147, 36.4%). It was still the most prevalent subtype (35.8%) in women younger than 40 years and the 40-60 age-group, The proportion of patients with TNBC is the highest in women aged less than 40 years with 19.3% compared to the other age categories. Finally, among women older than 60 years, the proportion of each subtype was relatively uniform. Most women received a diagnosis of stage II disease. Triple negative subtype increased overall mortality in advanced staging (stages III and IV) (aHR:1.42, 95% CI: 0.96-2.11). The 5-year overall survival rate was found in luminal A-like at 82.8%, luminal B-like at 77.6%, HER-2 enriched at 66.4% and triple negative subtype at 64.2%. CONCLUSION: The histologic subtype, correlated with age and staging influenced the OS. Our results confirmed the association of triple negative BC with poor prognosis especially in advanced stage. The adjuvant medical treatment in our country could not be accessible in some group of patients, so the results of treatment and survival especially HER-2 enriched are lower than other countries without treatment barrier.

The International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy Cytopathology.

The International Academy of Cytology (IAC) gathered together a group of cytopathologists expert in breast cytology who, working with clinicians expert in breast diagnostics and management, have developed the IAC Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy (FNAB) Cytology. The project was initiated with the first cytopathology group meeting in Yokohama at the 2016 International Congress of Cytology. This IAC Yokohama System defines five categories for reporting breast cytology, each with a clear descriptive term for the category, a definition, a risk of malignancy (ROM) and a suggested management algorithm. The key diagnostic cytopathology features of each of the lesions within each category will be presented more fully in a subsequent atlas. The System emphasizes that the crucial requirements for diagnostic breast FNAB cytology are a high standard for the performance of the FNAB and for the making of direct smears, and well-trained experienced cytopathologists to interpret the material. The performance indicators of breast FNAB, including specificity and sensitivity, negative predictive value, positive predictive value and ROM stated in this article have been derived from the recent literature. The current practice of breast FNAB has evolved with the increasing use of ultrasound guidance and rapid on-site evaluation. Two recent publications have shown a range of ROM for the insufficient/inadequate category of 2.6-4.8%, benign 1.4-2.3%, atypical 13-15.7%, suspicious of malignancy 84.6-97.1%, and malignant 99.0-100%. The management algorithm in the System provides options because there are variations in the management of breast lesions using FNAB and core-needle biopsy in those countries utilizing the "triple test" of clinical, imaging, and FNAB assessment, and also variations in the availability of CNB and imaging in low- and middle-income countries. The System will stimulate further discussion and research, particularly in the cytological diagnostic features of specific lesions within each category and in management recommendations. This will lead to continuing improvements in the care of patients with breast lesions and possible modifications to the IAC Yokohama System.

Real-world outcomes of different treatments in the management of patients with HER-2 positive breast cancer: a retrospective study.

OBJECTIVE: To investigate the treatment outcome in terms of relapse free survival and overall survival, and explore the determinants of the clinical outcome in HER-2/neu positive breast cancer patients who received or not received adjuvant trastuzumab. MATERIAL AND METHOD: The authors reviewed retrospectively of newly diagnosed non-metastatic breast cancer patients at the Faculty of Medicine, Chiang Mai University between January 2004 and December 2007. Comparisons were made between the two cohorts, women who did not receive adjuvant trastuzumab (100 patients) and women who received adjuvant trastuzumab (14 patients). RESULTS: The median follow-up time was 4.7 years. Four-year relapse-free survival (RFS) and overall survival (OS) in patients receiving trastuzumab was 92.3% and 100%, respectively. In the cohort of HER-2 positive patients who did not receive trastuzumab, the 4-year RFS in this group was 68.2% and 4-year OS was 87.8%. The difference was not statistically significant between the 4-year RFS rates (p = 0.103) and the 4-year OS rates (p = 0.214). By multivariate Cox regression analyses, only nodal status was identified as the independent predictors for superior RFS (hazard ratio 2.93; 95% CI, 1.07 to 5.88; p = 0.034) and none of the clinical parameters were significant predictors for 4-year overall survival. CONCLUSION: A hospital-based analysis of adjuvant Trastuzumab use in our center does not demonstrate the different treatment outcome. However there is a trend of favorable outcome in the group receiving adjuvant trastuzumab.

Investigation of dogs as a reservoir of Penicillium marneffei in northern Thailand.

BACKGROUND: Penicillium marneffei is a dimorphic pathogenic fungus endemic in Southeast Asia that usually causes disseminated disease, mainly in immunocompromised individuals, especially those with HIV infection. Untreated cases are usually fatal. The only known natural reservoir exists in bamboo rats and there is no firm evidence that these animals are involved in direct transmission to humans. The risk of infection is not restricted to those living in endemic areas; HIV-infected individuals who travel to Southeast Asia have also become infected by P. marneffei. Hence, there must exist sources to which even tourists are exposed on a short-term basis. DESIGN AND METHODS: Penicillium is known to infect dogs and this animal is common in the streets and temple areas of Chiang Mai, where there is one of the highest incidences of P. marneffei infection in the world. Dogs have not been well studied as a possible reservoir. To investigate this possibility, we took nasal swabs from 83 outdoor dogs and performed culture and nested polymerase chain reaction (PCR) to detect P. marneffei. RESULTS: We found that approximately 13% of nasal swabs from dogs in Chiang Mai, Thailand were positive when tested by two different PCR methods, but culture results were negative. Sequencing the products from both PCR reactions showed 100% identity with P. marneffei, whereas no other known fungi shared both sequences. CONCLUSIONS: Our results suggest that dogs might be an animal reservoir for P. marneffei in northern Thailand. This observation should be confirmed by additional studies.

Persistent hyperinsulinemic hypoglycemia of infancy associated with congenital neuroblastoma: a case report.

The authors report a rare case of persistent hyperinsulinemic hypoglycemia of infancy (PHHI) with congenital neuroblastoma without feature(s) of Beckwith-Wiedemann syndrome. A term newborn with a birth weight of 3,900 g developed hypoglycemia one hour after birth and required up to 20 mg/kg/min of intravenous glucose infusion to maintain euglycemia. Investigations during the critical period revealed an inappropriately high insulin level. An abdominal CT scan revealed a normal pancreas, right suprarenal mass, and liver nodules. A condition of stage 4S neuroblastoma was suspected and supported by an increased ratio of urine vanillylmandelic acid to creatinine. The bone marrow smear was normal. She underwent near total pancreatectomy at the age of 2 months. The suprarenal mass and liver nodules were not found during the operation or during repeated abdominal CT scans at 3 month of age. Spontaneous regression of neuroblastoma was suspected. The pathology of the pancreas was compatible with PHHI.

A study of high-nuclear-grade breast cancer in Thailand: subclassification and correlation with prognostic factors and immunohistochemical study.

OBJECTIVES: To classify high-nuclear-grade breast cancer (BC) into typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), and non-medullary carcinoma (NMC), and luminal A, luminal B, and HER2, and to correlate these tumors with other prognostic factors. MATERIALS AND METHODS: A retrospective study reviewing high-nuclear-grade BCs. The patients' age, histologic types, various histologic features, axillary lymph node (ALN) status, and results of immunohistochemical (IHC) study were recorded and analyzed. RESULTS: One-hundred and eighty-one cases of high-nuclear-grade BCs were reviewed and categorized into IDC, NOS (140, 77.3%), TMC (1, 0.6%), AMC (21, 11.6%), and others (19, 10.5%). The median age was younger in AMC than in NMC patients. NMC patients had a higher incidence of LVI and ALN metastasis with involvement of more than four lymph nodes (p = 0.006) whereas AMC patients had a higher mitotic index. Forty-six (35.9%) cases were triple-negative (TN), including 1 (100%), 7 (53.9%) and 38 (33.3%) cases of TMC, AMC, and NMC, respectively. AMC had a significantly lower number of node metastases (p = 0.006) than NMC; whereas TN had higher MI (p = 0.001) than non-TN. The non-TN group was subclassified into luminal A, luminal B, and HER2. Of these, TN and luminal B occurred at younger age (p = 0.01) whereas TN and luminal A had a higher mitotic count. TN had lower incidence of LNM including higher number of LNM. CONCLUSION: Overall, AMC-TN group showed a basal-like prognostic factor expression. NMC may be separated into TN and non-TN, with possibly different behavior. These sub-groupings should continue to be used. Interestingly, luminal A in our study tended to correlate with poor prognostic factors, thus, luminal A with high nuclear grade may not be representative of the usual luminal group profiles.

Breast cancer in the elderly: a histological assessment.

AIMS: To understand the correlation between the expression status of different biological markers in breast cancers in the elderly. METHODS AND RESULTS: Three hundred and ninety-seven cases were evaluated for expression of hormone receptors [oestrogen receptors (ER) alpha and beta, progesterone receptor (PR)], basal markers [p63, cytokeratin (CK) 5/6 and CK14] and others (HER2/neu, synaptophysin and chromogranin). The expression rates were 60, 29, 25, 6, 14, 8, 28, 17 and 5%, respectively, for these markers. The expression of ER alpha and beta, PR, synaptophysin and chromogranin at any level correlated with low nuclear or tumour grades, whereas the expression of HER2/neu, CK5/6 and CK14 at any level correlated with high nuclear grade. By using hierarchical clustering, groups of HER2, luminal and basal types were identified. In addition, a neuroendocrine group was also identified, being characterized by expression of synaptophysin, chromogranin, ER and PR, but not HER2/neu, and other basal cytokeratins. This group was associated with lower nuclear grade, and hence better prognosis. CONCLUSIONS: Breast cancer in the elderly shows similar molecular groupings as other breast cancers, with an additional neuroendocrine group that is associated with a favourable biological marker profile.

Bilateral low-grade B-cell lymphoma of the breast: a case report with cytological, histological and immunohistochemical studies.

A 45-year-old woman presented with bilateral palpable breast masses, which were clinically suspicious of either mammary carcinomas or phyllodes tumors. Fine needle aspiration (FNA) study suggested low-grade lymphoma. Histological and immunohistochemical studies of an incisional biopsy specimen of the left breast lesion confirmed the diagnosis of low-grade B-cell lymphoma. Computerized tomographic scans of chest and abdomen revealed multiple lymphadenopathy in the mediastinum and intra-abdomen. After receiving chemotherapy, marked reduction in size of both breast masses and the internal lymph nodes was observed. Primary lymphomas of the breast are rare, particularly those with bilateral involvement. FNA is an inexpensive diagnostic tool for breast lumps that can reliably distinguish carcinoma, sarcoma and lymphoma. Although it is often difficult for the cytological study to differentiate low-grade lymphoma from reactive lymphoid proliferation, FNA results in combination with clinical and radiological studies (triple testing) generally provide guidance for appropriate investigations, and helps avoiding unnecessary major operation.

Spectrum of papillary lesions of the breast: clinical, imaging, and pathologic correlation.

OBJECTIVE: Papillary lesions of the breast are a heterogeneous group of lesions that are difficult to diagnose as benign or malignant. The purpose of this article is to review clinical presentation, imaging features, and pathologic correlation of papillary lesions of the breast and to discuss the prognosis and management of these lesions. CONCLUSION: Recognition of the variety of benign and malignant papillary lesions of the breast will facilitate diagnosis and proper management.

Fine needle aspiration cytology of breast cancer in women aged 70 years and older.

AIMS: Elderly breast cancers are associated with a more favourable biological marker profile and higher proportion of specific subtypes, some of which are of low histological grade. We reviewed the fine needle aspiration cytology (FNAC) to assess the cytological characteristics and any clues to assist in the diagnosis. METHODS: The aspirates of 140 cancers of various histological types and grades and 39 benign lesions were evaluated for 13 cytological parameters including cellularity of the direct and cytospin smears, epithelial cell clusters, cellular atypism, cytoplasmic features, vacuoles, mitotic figures, presence of myoepithelial cells, single background epithelial cells, the presence of naked nuclei, stromal fragments and necrosis. RESULTS: We found that the presence of background single epithelial cells, atypism of such cells, absence of benign appearing epithelial fragments, nuclear atypism of the epithelial cells within the fragments, presence of moderate amount of cytoplasm of these cells, absence of myoepithelial cells within the cluster, and absence of bipolar nuclei in the background have a strong association with malignancy. Scoring only the presence of single cells in the background, single cell atypism and the absence of bipolar nuclei in a scoring system can differentiate between benign and malignant aspirates with high (>90%) sensitivity and specificity. CONCLUSIONS: Assessing the presence of single cells in the background, single cell atypism and the absence of bipolar nuclei facilitates identification of malignancy in the aspiration of breast lesions from elderly patients.

Fine needle aspiration cytology in young women with breast cancer: diagnostic difficulties.

BACKGROUND: Breast carcinoma is the most common malignancy in women worldwide. Though fine needle aspiration cytology (FNAC) plays an important role in preoperative diagnosis, there may be diagnostic delays in affected young women due to a lower index of suspicion. METHODS: The files of the Departments of Pathology, Singapore General Hospital, Singapore, and Prince of Wales Hospital, Hong Kong, were searched for cases of breast carcinoma in women aged 35 years or less. Those with prior FNA procedures comprised our study group. The FNA smears were reviewed and classified into five categories: inadequate, benign, equivocal, suspicious, malignant. The findings were correlated with subsequent histology. RESULTS: Thirty-four women aged 35 years and below underwent 35 FNACs, with one woman having bilateral FNA procedures. Upon review, one (2.9%) was classified as inadequate, one (2.9%) benign, five (14.3%) equivocal, five (14.3%) suspicious, 21 (60%) malignant and slides were not available for review for two (5.6%) cases. For six benign and equivocal cytological diagnoses, subsequent histology disclosed pure ductal carcinoma in situ (DCIS, 1 case), mucocoele-like lesions with DCIS (2 cases), invasive and in situ ductal carcinoma with neuroendocrine features (1 case) and two cases of invasive ductal carcinoma. CONCLUSION: Diagnostic difficulties in cytological interpretation of aspirates from breast carcinoma in young women may lead to unwanted delays, which occurred in six (17.6%) of 34 women in our series. Low grade cancers posing a pitfall in cytological diagnosis have to be considered.

Telomerase and markers of cellular proliferation are associated with the progression of cervical intraepithelial neoplasia lesions.

The expression of the catalytic subunit of telomerase protein (human telomerase reverse transcriptase [hTERT]), which is associated with telomerase activity, was evaluated as a potential marker of the high-grade premalignant cervical intraepithelial neoplasia (CIN 2/3) lesions. For comparison, cases of normal cervical squamous mucosa, low-grade CIN1 lesion, and cervical squamous cell carcinoma were included. The hTERT expression was also compared with Ki-67 and topoisomerase II-alpha (TPII-alpha) to determine the proliferative activity of the hTERT-positive dysplastic cells by a quantitative immunohistochemical staining method and was classified as follows: negative, 5% or less; moderate, 6% to 50%; or high, greater than 50% of the positive cells. The hTERT-positive cells were detected in a patchy pattern in the lower parabasal layers and in much of the basal layer in normal squamous mucosa. A similar frequency of Ki-67- or TPII-alpha-positive cells was observed, with the exception of the basal layer cells that were mostly negative. It is worthy to note that the recognizable intact basal layer cells in cases of CIN lesions were also consistently positive for the expression of hTERT, but rarely for Ki-67 or TPII-alpha. The expression of hTERT was detected in a less patchy pattern at a high or moderate percentage of the dysplastic epithelial cells each in 28.5% of cases of CIN1 lesions. A similar frequency, high and moderate percentage combined, of the TPII-alpha-positive dysplastic cell was also observed. In contrast, a high percentage of the hTERT-positive dysplastic cells were detected as diffuse basal or full-length thickness in 87.5% or 95% of cases of CIN2 or CIN3, respectively. A similar frequency of Ki-67 or TPII-alpha expression was observed in the dysplastic cells of CIN3 lesions. The pattern of hTERT-positive malignant cells in squamous cell carcinoma and dysplastic cells in the high-grade CIN lesions, to a greater extent, and dysplastic cells in the low-grade CIN lesion, to a lesser extent, was distinct from that of the normal cervical squamous mucosa. The results suggest that the progressive increase in the hTERT expression, together with the proliferative activity of the dysplastic epithelial cells of the high-grade CIN lesions, represents an early genetic abnormality in cervical pathogenesis.

Fine needle aspiration for evaluation of breast masses.

PURPOSE OF REVIEW: Fine needle aspiration has been used for many years as a diagnostic tool for breast lesions, with high sensitivity and specificity. There is controversy as to whether this technique should be replaced by other diagnostic procedures such as core biopsy. This review aims to re-evaluate the usefulness of breast fine needle aspiration. RECENT FINDINGS: During the past 10 years many institutions have replaced fine needle aspiration by core biopsy and related techniques such as vacuum-assisted core biopsy and advanced breast biopsy instrument action. Other institutions continue to use fine needle aspiration as a first line of investigation for breast lesions. This technique is especially useful in radiologically benign lesions and when combined with image guidance. The use of the 'triple test' (combined cytologic, clinical and radiologic findings) decreases false-negative and false-positive results. SUMMARY: Fine needle aspiration continues to be an acceptable and reliable procedure for the preoperative diagnosis of breast lesions, particularly in developing countries, and when used as part of the 'triple test'. Accurate diagnosis requires experience in both aspiration technique and specimen interpretation. Clinicians should be mindful of the limitations of the technique. The choice between fine needle aspiration and core biopsy should be individualized for the patient.

Fine-needle aspiration cytology of metaplastic carcinoma of the breast.

BACKGROUND: Metaplastic carcinoma of the breast encompasses a heterogeneous group of tumours with variable components of sarcomatoid, squamous or poorly differentiated carcinomas. AIM: To review a series of 19 cytological preparations of metaplastic carcinomas to assess diagnostic cytological features. METHODS: 17 cases of fine-needle aspirates of histologically proven metaplastic carcinomas (4 monophasic spindle cell carcinomas, 4 squamous cell carcinomas and 11 biphasic tumours) were reviewed, with an emphasis on the presence of poorly differentiated carcinoma, squamous cell carcinoma, atypical spindle cells, benign stromal fragments and necrosis. RESULTS: All cases were diagnosed as malignant, with 68% of cases showing moderate to high cellularity, and 47% showing necrosis. If the tumours were analysed according to the constituting components histologically, 7, 15 and 8 cases, respectively, possess poorly differentiated carcinoma cells, sarcomatoid malignant cells and squamous carcinoma cells, whereas these components were cytologically identified in 11, 10 and 7 cases, respectively. Dual tumour populations were identified in only 5 of the 11 biphasic carcinomas in the cytological preparations; and the stromal material was cytologically identified in the only case with chondroid stroma. CONCLUSIONS: Identification of metaplastic carcinoma in cytology remains problematic. There seems to be morphological overlap between various components. The identification of dual components, unequivocal squamous carcinoma cells and chondroid stroma is helpful for diagnosis, but it is uncommon. The presence of poorly differentiated carcinoma cells with a suggestion of focal spindle morphology is another clue to the suggestion of metaplastic carcinoma.

Magnetic resonance imaging of breast lesions--a pathologic correlation.

Magnetic resonance imaging of the breast is useful in assessing breast lesions. An understanding of the pathologic characteristics of the tumors may help to understand these magnetic resonance imaging observations.Large lesional size (>10 mm), ill-defined margin, and irregular outlines are associated with malignancy. These correlate with the pathological features of breast tumor, characterized by rapid growth rate, large size, and infiltrative growth pattern, invasion into stroma resulting in desmoplasia, and hence irregular outline and margin. The detection and estimation of tumor extent of invasive lobular carcinoma is problematic, even with magnetic resonance imaging, which is considered the most sensitivity. This inaccuracy likely derives from the characteristic linear, single cells infiltration growth pattern of the tumor, which is also often underestimated by clinical examination. Estimation of tumor extent after neoadjuvant chemotherapy is also essential but problematic by imaging, as the shrunken tumor becomes fibrotic, with stromal hyalinization, diminished microvasculature and tumor break up causing size underestimation. Non-enhancement of breast tumors occurs in about 8% of cases correlates with diffuse growth pattern, particularly of infiltrative lobular carcinoma. The observation of disproportionately high non-enhancing ductal carcinoma in situ remains an enigma. Finally, early rim enhancement correlates with small cancer nests, low ratio of peripheral to central fibrosis and high ratio of peripheral to central microvessel density. These may be related to increased vascular endothelial growth factor mediated increased microvessel density as well as increased permeability, which manifest as increased rapid contrast uptake and dissipation.

Endothelin-1 expression correlates with atypical histological features in mammary phyllodes tumours.

BACKGROUND AND AIMS: Endothelin-1 expression is increased in infiltrating duct carcinoma and is associated with larger tumour size, higher histological grade and lymphovascular permeation. This has not been evaluated in phyllodes tumours, which are uncommon fibroepithelial lesions with potential for local recurrences or distant metastasis. While the grading of phyllodes tumours depends on a combination of histological parameters, prediction of their behaviour remains difficult. METHOD: A large series of 461 phyllodes tumours (291 benign, 115 borderline malignant and 55 frankly malignant) were evaluated for endothelin-1 expression in both the epithelial cells and stromal cells by immunohistochemistry; results were correlated with the tumour grade. RESULTS: For benign phyllodes tumours, the epithelial staining of endothelin was negative, weak, moderate and strong in 6%, 26%, 15% and 53% of cases respectively; results were 4%, 18%, 19% and 59% respectively for borderline and 6%, 18%, 6% and 70% respectively for frankly malignant tumours. For the stromal staining, the negative, weak, moderate and strong staining was 32%, 19%, 18% and 31% respectively for benign phyllodes, 24%, 13%, 10% and 53% respectively for borderline and 8%, 16%, 17% and 59% respectively for frankly malignant tumours. There was correlation between epithelial and stromal staining, and the stromal staining correlated with histological features of stromal cellularity, stromal cell nuclear pleomorphism, margin status and stromal overgrowth. CONCLUSION: These observations suggest a close relationship between the epithelial and stromal elements in phyllodes tumours; endothelin may play a significant role in the malignant progression of phyllodes tumours.

Overexpression of E-cadherin protein in metastatic breast cancer cells in bone.

AIM: The aim of the present study was to evaluate E-cadherin, whose expression remains poorly understood in the intercellular adhesion of metastatic breast cancer cells in bone, the most prevalent site for metastatic growth. MATERIALS AND METHODS: An immunohistochemical staining method was used for the localization of E-cadherin protein in tissue biopsy specimens of normal breast (n = 9) and well- (n = 8), moderately (n = 8) or poorly (n = 14) differentiated invasive primary breast cancer and metastatic breast cancer in bone (n = 17). The expression patterns of E-cadherin were classified as homogeneous (most cells exhibiting positivity), heterogeneous (a few scattered patches of cells with positivity) or negative (cells with undetectable positivity). RESULTS: Normal breast epithelial cells showed homogeneous overexpression of E-cadherin in all cases. A progressive and statistically significant reduction of E-cadherin expression was detected in the histologically well- to moderately to poorly differentiated breast cancer cells (p < 0.001). The clumps of invasive primary breast cancer cells in CD-31-positive blood vessels exhibited E-cadherin expression. Moreover, as compared to the poorly differentiated breast cancer cells, a significantly increased frequency of the metastatic breast cancer cells in bone exhibited homogeneous expression of E-cadherin in 15 out of 17 and heterogeneous expression in the remaining 2 cases (McNemar Exact p < 0.001). This is the first demonstration of membranous overexpression of E-cadherin on metastatic breast cancer cells in bone; the high frequency of its expression may have a role in the intercellular adhesion of metastatic cells in bone.

p63 is useful in the diagnosis of mammary metaplastic carcinomas.

AIMS: p63 has been recently reported to be expressed in sarcomatoid/metaplastic carcinoma of the breast, in addition to its role as a myoepithelial marker. A large series of 34 metaplastic carcinomas, including cases with pure epithelial component (squamous cell and adenosquamous carcinomas), biphasic tumours with carcinomatous and sarcomatoid components and monophasic tumours with only spindle cell component, were evaluated for p63 expression with respect to the different cellular components. METHODS: All of the metaplastic carcinomas were assessed for p63 and conventional epithelial and mesenchymal markers of AE1/3, CAM5.2 and vimentin by immunohistochemistry. RESULTS: All of the different categories of metaplastic carcinomas showed similar clinico-pathological features (patient age, tumour size, nuclear grade, mitotic activity, lymph node status and hormonal receptor status). For metaplastic carcinoma with epithelial component only, p63 was only expressed in the squamous cell component, but not the adenocarcinoma component. Eight of the 10 tumours were positive for p63. For the tumours with sarcomatoid component, either singly or together with carcinomatous component, p63 was positive in 14 of 24 cases. Pure sarcomas and carcinomas were all negative for p63 staining by immunohistochemistry, thus rendering p63 staining highly specific for diagnosing metaplastic carcinoma. CONCLUSIONS: Using p63 for diagnosis of metaplastic carcinoma gives a sensitivity of 65%, a specificity of 96%, a positive predictive value of 96%, and a negative predictive value of 66% and an accuracy of 78%. p63 may be used as an adjunct marker in the diagnosis of metaplastic carcinoma.

Wnt pathway component LEF1 mediates tumor cell invasion and is expressed in human and murine breast cancers lacking ErbB2 (her-2/neu) overexpression.

This study examines the role of LEF1, a component of the Wnt signaling pathway, in human breast and murine mammary carcinoma and its relationship to ErbB2 (her-2/neu) expression. Mammary tissue and tumors from 5 different Wnt pathway-activated transgenic mouse strains and 5 different ErbB2 pathway-activated transgenic mouse strains were studied for the amount and distribution of expression of beta-catenin and LEF1. Fourteen samples of human infiltrating ductal breast cancer arising from a background of ductal carcinoma in situ (DCIS) were analyzed for LEF1, estrogen and progesterone receptor (ER and PR) and her-2/neu expression. in vitro, the effect of estradiol on LEF1 protein expression was examined in several breast cancer cell lines. The functional role of LEF1 was analyzed by a Matrigel invasion assay following transfection of breast cancer cell lines with either an LEF1 expression construct or a dominant-negative LEF1 construct. A significant (p=0.023) negative correlation between the expression of LEF1 and her-2/neu was observed in human breast cancer. LEF1 was strongly expressed, and beta-catenin had nuclear localization, in mammary tumors derived from Wnt pathway transgenic mice but not in ErbB2 pathway transgenic mice. In estrogen-receptor-positive breast cancer cell lines, LEF1 protein expression increased significantly following estradiol incubation (>200% of baseline). Following transient transfection, overexpression of LEF1 promoted and dominant-negative LEF1 inhibited tumor cell invasion. LEF1, a downstream component of the Wnt signaling pathway, defines a distinct, her-2/neu negative (non-overexpressing) subset of breast/mammary cancers in both humans and mice, mediates breast cancer cell invasion, and may be regulated in part by estradiol.

A two-phase study model for the standardization of HER2 immunohistochemical assay on invasive ductal carcinoma of the breast.

OBJECTIVES: To develop and verify a standardized protocol for HER2 immunohistochemical assays on invasive ductal carcinoma of the breast in Thailand. MATERIAL AND METHOD: A two-phase study approach was employed. In the Phase One, after verifying the proposed protocol that adopted the HercepTest procedure using readily available primary antibodies, CB11 and A0485, Lab 1 performed the HER2 immunohistochemical staining for 137 cases of invasive ductal carcinoma twice with two types of the antibody. Nine pathologists from 8 centers independently examined and scored all the 2 x 137 stained slides that were blinded for antibody type. Interobserver reliability was calculated using pair-wise kappa. Following discussion of the results, the Phase Two study was planned. Lab 2 and Lab 3 independently performed the HER2 staining according to the protocol for 60 invasive breast carcinoma cases. The same group of pathologists scored 2 x 60 stained slides that were masked for laboratories. Interobserver reliability and interlaboratory agreement from each pathologist were calculated using kappa statistics. Three interpreted categories--namely negative, equivocal and positive tests were used in the analyses. RESULTS: Phase One study showed interobserver agreement between pairs varied from kappa 0.75 (95%CI, 0.68-0.82) to 0.06 (95%CI, 0-0.14) while Phase Two study obtained pair-wise kappa scores ranged from 0.84 (95%CI, 0. 80-0.89) to 0. 65 (95%CI, 0.59-0.71). Interlaboratory kappa for each pathologist was 0.67 (95%CI, 0.61-0.73). CONCLUSION: The standardization of HER2 immunohistochemical assay was achieved through this two-phase study model. It had added benefits of improving pathologists' expertise and verifying the HER2 testing protocol to be used in Thailand.