Advances in the Molecular Analysis of Breast Cancer: Pathway toward Personalized Medicine

Background

Breast cancer is a heterogeneous disease that encompasses a wide range of clinical behaviors and histological and molecular variants. It is the most common type of cancer affecting women worldwide and is the second leading cause of cancer death.

Methods

A comprehensive literature search was performed to explore the advances in molecular medicine related to the diagnosis and treatment of breast cancer.

Results

During the last few decades, advances in molecular medicine have changed the landscape of cancer treatment as new molecular tests complement and, in many instances, exceed traditional methods for determining patient prognosis and response to treatment options. Personalized medicine is becoming the standard of care around the world. Developments in molecular profiling, genomic analysis, and the discovery of targeted drug therapies have significantly improved patient survival rates and quality of life.

Conclusions

This review highlights what pathologists need to know about current molecular tests for classification and prognostic/predictive assessment of breast carcinoma as well as their role as part of the medical team.

Beta-catenin expression patterns in matched pre- and post-neoadjuvant chemotherapy-resistant breast cancer

BACKGROUND

β-catenin is a critical component of the cadherin cell-to-cell adhesion pathway and a key participant in the Wnt signaling pathway. Activation of β-catenin signaling in the Wnt pathway is a known contributor to tumor cancer progression and metastasis and may result in resistance to chemotherapeutic agents. The aim of this study is to evaluate the patterns of expression of β-catenin in breast carcinoma cells before and after neoadjuvant chemotherapy. Discovery of the molecular mechanisms responsible for resistance to chemotherapy treatment could result in more effective therapy, and improve outcome and survival.

DESIGN

Twenty-nine matched pre-treatment and post-neoadjuvant chemotherapy breast carcinomas were subjected to immunohistochemical study using anti-β-catenin antibody. Normal staining was defined as crisp membrane staining in >90% tumor cells; aberrant expression was nuclear staining in >5% tumor cells.

RESULTS

Of the 29 included cases, five cases of invasive lobular carcinoma lacked β-catenin immunoreactivity pre- and post-treatment. Mildly reduced membranous staining was seen in two post-treatment samples. One case of triple-negative ductal carcinoma had reduced pre- and post-treatment staining. All other cases showed normal pre- and post-treatment β-catenin expression. No aberrant staining was identified.

CONCLUSION

In our study, there was no difference in the expression of β-catenin in pre- and post-neoadjuvant chemotherapy specimens. These results do not suggest that β-catenin plays a role in conferring neoadjuvant chemotherapy resistance.

Pleomorphic lobular carcinoma of the breast: a morphologically and clinically distinct variant of lobular carcinoma

Pleomorphic lobular carcinoma is an uncommon variant of lobular carcinoma, characterized by significant cytologic atypia that contrasts with the low pleomorphism of classical lobular carcinoma. It accounts for approximately 1% of all epithelial breast malignancies. In addition to its pleomorphism, it is characterized by aggressive behavior and shortened patient survival. Although the morphologic features of pleomorphic lobular carcinoma are well described, it often eludes accurate pathologic characterization. Some controversy surrounds the pathogenesis of pleomorphic lobular carcinoma; however, it is now considered a well-defined variant of invasive lobular carcinoma. Pleomorphic lobular carcinoma shares molecular alterations with classical lobular carcinoma, such as alterations in the gene CDH1 on chromosome band 16q22 that results in changes in E-cadherin protein function. The aggressive biology of pleomorphic lobular carcinoma relates to the acquisition of genetic alterations typical of high-grade ductal carcinoma, such as overexpression of HER2/neu and c-myc.

Diagnostic benefits and cost-effectiveness of on-site imprint cytology adequacy evaluation of core needle biopsies of bone lesions

BACKGROUND

Core needle biopsy (CNB) is a well-established, successful technique for the diagnosis of various organ system lesions. To increase diagnostic yield, on-site cytologic evaluation of adequacy (OCA) is routinely performed at many institutions. Numerous studies evaluating the impact of OCA on CNB have been published. However, little has been said regarding accuracy of OCA for bone lesions.

METHODS

To evaluate this, we reviewed our experience during a two-year period, and compared OCA results with the final diagnosis of the corresponding CNB. For the study, diagnoses were divided into three categories: malignant, benign, and nonspecific/nondiagnostic findings.

RESULTS

Sixty-one cases were included. During OCA, 25 cases were diagnosed as malignant, three cases as benign, and 33 as nonspecific/nondiagnostic. On histologic evaluation, 29 cases were malignant, 16 were benign, and 16 were classified as nonspecific/nondiagnostic. Concordance with final CNB diagnosis was seen in 100% of malignant, 67% of benign, and 45% of nonspecific/nondiagnostic on-site cytology evaluations. The overall diagnostic success rate of OCA for malignancy was 86% (25/29). The success rate of OCA for benign lesions was only 13%. Fifty-four percent of cases were diagnosed as nonspecific/nondiagnostic on-site. This category included four false negative cases.

CONCLUSIONS

We conclude that for lesions with a suspicion of malignancy, OCA is a valuable adjuvant diagnostic tool. However, for cases with a benign or nonspecific clinical impression, OCA has a limited diagnostic role. Careful selection of cases in which OCA is beneficial is necessary to maintain accuracy and to limit procedure costs.

Smith Lemli-Opitz syndrome: a contribution to the delineation of a cognitive/behavioral phenotype

AIM

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive congenital malformation syndrome caused by an inborn error of cholesterol biosynthesis. The incidence is around 1:20000-1:70000. SLOS phenotype is very broad: severe phenotypes show exitus in perinatal period while milder phenotypes only show behavioral and learning problems. The purpose of this study is to further contribute to the delineation of a cognitive and behavioral phenotype in SLOS.

METHODS

Nine patients with SLOS aged between 22 months and 25 years have been followed at the Department of Pediatrics, University of Naples "Federico II" for 2 years. A neuropsychologic study has been carried out in order to assess motor development, adaptive skills, social behavior, communication and language, temperament, aggressive behavior, symptoms typical of autism spectrum disorders (ASDs).

RESULTS

The overall assessment of cognitive/behavioral phenotype showed severe / profound mental retardation in most of them (8/9) with a quite homogeneous neuropsychological profile. The language area was deficient both in expressive and receptive skills. Adaptive skills were in line with mental development. The presence of behavior problems (self-injury and stereotypies) was detected in 6 patients. The study of temperament showed a trend towards a sedentary lifestyle, lack of inhibition against novelty and danger, and reduced interest in the stimuli. None of our patients could be diagnosed as having ASDs.

CONCLUSION

Although a specific behavioral phenotype for SLOS has gained support in the literature, we believe that many of the features described in individuals with SLOS are common to other mental retardation syndromes.

Cyclin E drives human keratinocyte growth into differentiation

Human epidermis is continuously exposed to environmental mutagenic hazard and is the most frequent target of human cancer. How the epidermis coordinates proliferation with differentiation to maintain homeostasis, even in hyperproliferative conditions, is unclear. For instance, overactivation of the proto-oncogene MYC in keratinocytes stimulates differentiation. Here we explore the cell cycle regulation as proliferating human keratinocytes commit to terminal differentiation upon loss of anchorage or overactivation of MYC. The S-phase of the cell cycle is deregulated as mitotic regulators are inhibited in the onset of differentiation. Experimental inhibition of mitotic kinase cdk1 or kinases of the mitosis spindle checkpoint Aurora B or Polo-like Kinase, triggered keratinocyte terminal differentiation. Furthermore, hyperactivation of the cell cycle by overexpressing the DNA replication regulator Cyclin E induced mitosis failure and differentiation. Inhibition of Cyclin E by shRNAs attenuated the induction of differentiation by MYC. In addition, we present evidence that Cyclin E induces DNA damage and the p53 pathway. The results provide novel clues for the mechanisms committing proliferative keratinocytes to differentiate, with implications for tissue homeostasis maintenance, HPV amplification and tumorigenesis.

Solid papillary carcinoma of the breast: a pathologically and clinically distinct breast tumor

Solid papillary carcinomas are tumors morphologically characterized by round, well-defined nodules composed of low-grade ductal cells separated by fibrovascular cores. These tumors are rare and affect predominantly older women. Although they are considered in situ carcinomas, debate and uncertainty still exist regarding their true nature, because immunohistochemistry for myoepithelial cells has shown absence of myoepithelial cell layer along the epithelial-stromal interface of the tumor in many cases. Clinically, these tumors present as a palpable, centrally located mass or as bloody nipple discharge. Pathologically, solid papillary carcinomas exhibit low-grade features, and often the tumors display neuroendocrine and mucinous differentiation. In the majority of cases an associated invasive carcinoma is present, with colloid and neuroendocrine carcinomas being the most common. The pathologic differential diagnosis is broad and ranges from benign to malignant lesions. The treatment for solid papillary carcinomas is surgical excision. When invasive carcinoma is not present, the prognosis is excellent.

Epilepsy in inherited metabolic disorders: a pediatric series

AIM

Our study aims at further defining the characteristics of epilepsy in Inherited Metabolic Disorders (IMDs).

METHODS

We reviewed the medical records of 345 patients with IMDs followed at the Metabolic Diseases Unit of our Department of Pediatrics and found the presence of an epileptic syndrome in 45 cases. An overview is given based on various criteria such as pathogenetic background, seizure type, age of onset, EEG, neuroimaging data, treatability. Seizure types were: focal (24 patients), generalized (13 patients), febrile (3 patients), and hypoglycemic (8 patients with glycogenoses). Some patients presented with more than one type of seizures. Age of onset was mainly during the first year of life (N.=19), between 2 and 6 years in 13 patients, and after the 6th year in 9 patients.

RESULTS

Available EEGs showed either focal (N.=21) or generalized epileptiform abnormalities (N.=11); multifocal paroxysms were evident in 3 patients while the remaining 3 patients had normal findings. Available neuroimages (CT/MRI) showed either normal findings (N.=6) or white matter abnormalities (N.=6), cerebral and/or cerebellar cortical atrophy (N.=11), hydrocephalus (N.=1), corpus callosum hypoplasia (N.=2), pontocerebellar hypoplasia (N.=1), gliosis in trigone area (N.=4). Most patients showed a favorable response to antiepileptic treatment (AEDs) with either complete control or reduced seizure frequency.

CONCLUSION

IMDs are a relatively rare cause of epilepsy in children but their diagnosis is very important with respect to treatment, prognosis and genetic counselling.

Cytologic features of fibrolamellar carcinoma with mucin production: a rare variant of combined hepatocellular-cholangiocarcinoma

Fibrolamellar carcinoma (FC) is an uncommon tumor that usually arises in non-cirrhotic livers of adolescents or young adults. It differs clinically from hepatocellular carcinoma in its better prognosis and lack of gender predilection. Cytologically, the tumor is composed of large polygonal cells with abundant cytoplasm, pleomorphic nuclei, and prominent large nucleoli. A variant of FC with mucinous differentiation has been previously described. These tumors have been regarded as combined hepatocellular cholangiocarcinomas. Herein, we report the case of a 44-year-old Asian female with a large liver mass present for approximately two years. Core needle biopsy with imprint cytology demonstrated FC with areas of intracellular mucin. To our knowledge, cytological features of this rare tumor have not been described before.

Spontaneous correction of anterior crossbite by RPE anchored on deciduous teeth in the early mixed dentition

AIM

The purpose of this study was to evaluate the effectiveness of Haas RPE anchored on deciduous teeth in the early mixed dentition, for inducing the spontaneous correction of permanent incisor's crossbite, without compliance, without post bite-plane and no involvement of the permanent teeth.

MATERIALS AND METHODS

The sample group comprised 50 consecutive patients (mean age 8y 5m, SD 2y 1m), 31 males, 19 females. They showed a cross-bite affecting one or more permanent incisors, for a total of 70 teeth. The patients were treated with Haas RPE appliance anchored on second deciduous molars and bonded on deciduous canines. No direct forces were applied on the permanent teeth.

RESULTS

Anterior crossbite self-corrected 'spontaneously' in 84% of the cases. Lateral incisors had a higher rate of self-correction than central incisors. All hyper-divergent subjects showed a spontaneous crossbite self-correction.

CONCLUSION

The early maxillary expansion by Haas RPE anchored on deciduous teeth is an efficient and effective procedure to induce the anterior crossbite self-correction in the early mixed dentition without the need of a bite-plane, no involvement of the permanent teeth and without compliance.

The unsatisfactory ThinPrep® Pap Test™: analysis of technical aspects, most common causes, and recommendations for improvement

ThinPrep® preparation is a widely-used method for processing gynecologic specimens due to the many advantages of the technique. However, the presence of blood, inflammation, and lubricant, among other factors, can significantly interfere with specimen adequacy. The aim of this study was to identify and overcome the most common reasons for unsatisfactory ThinPrep® Pap Test™ results in our laboratory. From October 2010 to January 2011, we reprocessed cases categorized as "unsatisfactory for evaluation" to determine whether reprocessing these specimens would impact the unsatisfactory rate. Reasons for unsatisfactory results were classified as: technical reasons, scant cellularity, and complete obscuring factors. Two hundred fifty-three cases were initially classified as unsatisfactory. Of these, 226 cases were reprocessed. Ninety cases became satisfactory after reprocessing with an overall improvement of 40%. The most common reasons for unsatisfactory results were the presence of lubricant (96 cases), presence of blood (64 cases), and technical problems (33 cases). Cases affected by blood or technical issues showed a significant improvement after reprocessing (56.2% and 90.9%, respectively). However, unsatisfactory cases owed to the presence of lubricant showed a relatively low percentage of improvement (16.6%). The main reasons for unsatisfactory results, the presence of blood and lubricant, can be avoided in many cases if sampling is not performed during bleeding and if the use of lubricants is limited during sample collection. Our study showed that reprocessing of selected cases can improve the overall unsatisfactory rate and can potentially reduce the risk of missing significant lesions.