Pathologist In Terms Research Articles

Liver biopsy versus non-invasive tests in determining liver disease status.

Dear Editor, I read with interest the article by Cakmakci et al. published in your journal recently (1). Although liver biopsy has been considered as the “gold standard” for defining liver disease status, and evaluating the progress of the disease, it is a risky procedure and there are a few limitations that affect the clinical acceptance of the process (2). Risk of bleeding due to invasiveness of the procedure is one of the factors that affects both patient and clinician tendency to the procedure (3). I agree with the authors that liver biopsy guided by ultrasonography is a safe procedure with a lower complication rate, it obtains sufficient liver specimen, and subsequently increases the probability of definitive pathological diagnosis. However, sampling error and inter-observer variability have raised questions on the value of liver biopsy in defining the status of liver disease (4). Thus, alternative noninvasive methods have been evaluated to obtain information on the extent of fibrosis by focusing on noninvasive blood marker indicators (4). Inter-observer and intra-observer reliabilities are other limitations in the pathological evaluation of liver biopsies. Some researchers have shown that in the evaluation of liver samples from chronic viral hepatitis, the level of experience of the pathologist in terms of specialization, duration, and location of practice has a stronger effect on the agreement compared to the characteristics of the specimen (5).

A brief literature review on an unusual prostate cancer - a case presentation

Background Small-cell neuroendocrine (NE) carcinoma accounts for only 1 % of all prostate cancers. However, it represents a distinct clinicopathological category and can pose certain difficulties to reporting pathologists in terms of determining primary or secondary status, and appropriate interpretation of immunohisto-chemical stains particularly in metastatic lesions. Case presentation Morphological and immunohistochemical (synaptophysin and thyroid-transcrition-factor-1 or TTF-1 positive; prostatic specific antigen negative) profiles of a metastatic small-cell NE carcinoma of prostate in a patient previously treated with antiandrogen and radiotherapy are presented. Literature review Immunohistochemical staining for all NE markers may be negative in 10% of cases, making morphological features the main diagnostic criteria. Prostatic-specific markers are negative in the majority of cases, which proves to be a diagnostic challenge. TTF-1 is not useful to exclude secondary disease from lung origin. The fact that many patients have a previous history of a hormonally treated prostatic adenocarcinoma of usual acinar type is important for correct diagnosis. Evidence suggests that NE carcinoma cells ‘transdifferentiate’ from non-NE cancer cells, and that among inducers of the process androgen deprivation is the most significant. Patients frequently present with metastatic disease to bone, liver, lung, and lymph nodes, and generally do not respond to hormonal or radiation therapy.

30. Hypopigmented CD8+ patch stage mycosis fungoides in an adolescent patient

Mycosis fungoides (MF) represents the most common form of cutaneous T cell lymphoma. The majority of cases represent a neoplastic proliferation of CD4+/CD8– T cells occurring in middle aged and older adults, often with initial presentation as long standing erythematous patches on non-sun exposed skin. There is, however, a wide range of clinical, morphological and immunophenotypic variation in the presentation of MF. Hypopig-mented MF (HyMF) is an uncommon clinical variant which appears to have a predilection for young patients with dark skin, and often shows a CD4–/CD8+ immunophenotype. These characteristics present significant challenges for the pathologist in terms of recognising the possibility of a form of MF and separation from inflammatory dermatoses, particularly the early ‘inflammatory’ phase of vitiligo. Additionally, when the proliferation is recognised as neoplastic, separation from aggressive forms of CD8+ T cell lymphoma is critical. We present a case of HyMF in a 16-year-old male showing the CD4–/CD8+ immunophenotype and discuss the differential diagnosis of and clinicopathological approach to these challenging cases.

Comparison of two histopathologic methods for evaluating subcutaneous reaction to mineral trioxide aggregate

Objectives: One of the most important factors for suitable materials for pulp therapy is biocompatibility. Two histopathologic methods of Cox and Federation Dentaire International (FDI) were used to evaluate inflammation. In Cox method, density of inflammatory cells, tissue reactions like fibrosis, vascular responses like congestion and fibrin extravasation have been used to evaluate inflammatory reactions. The aim of this study was to compare the accuracy of pathologists’ interpretations using two different methods. Study design: Three pathologists observed the degree of inflammation in 225 histopathologic sections. These sections showed inflammation in subcutaneous connective tissue of rats adjacent to polyethylene tubes, filled with white or gray mineral trioxide aggregate. Empty tubes served as controls. Samples were harvested after 7-, 15-, 30-, 60-, and 90-days. All pathologists examined the sections under a light microscope (Carl Zeiss, Oberkochen, Germany) at ×400 magnifications. Chi-Square test was used to evaluate the difference between inflammation grades when one pathologist used two methods. Cohen’s Kappa value was used to measure agreement of three pathologists to recognize the degrees of inflammations when using one of the methods. Results: There were no significant differences between the two methods when one of the pathologist used these methods to report the degree of inflammation (p=0.054). However, two other pathologists reported significant differences between two methods (p=0.005, p=0.001). In the FDI method, there was an acceptable agreement between first and second, and first and third pathologist in terms of the degree of inflammation, and intermediate agreement existed between the second and third pathologist. With the Cox method, no agreement among the pathologists could be found. Conclusion: The results of three pathologists in terms of rating inflammation with the FDI method showed better agreement than with the Cox method. Therefore, FDI method is more reliable than the Cox method to evaluate inflammation. Key words: Biocompatibility, connective tissue, infammation, mineral trioxide aggregate.

Disambiguating epigenetics

An understanding of epigenetics is now essential for the clinical pathologist in terms of disease pathogenesis, prognostication and therapeutic opportunities. Yet epigenetics, the study of inherited altered gene expression despite an unchanged DNA sequence, remains a source of confusion for many. For example, it is often difficult to appreciate parent-of-origin effects involving genomic imprinting including covalent (DNA methylation) and non-covalent changes (DNA-protein and DNA-RNA interactions, chromatin remodelling). In this talk I will highlight the importance of developments in RNA biology with a special focus on non-coding RNAs and microRNAs. Burgeoning subsets of RNA molecules are being identified that do not encode protein and function predominately as regulators of gene expression.¹ One of the most widely studied subset contains microRNAs, which are tiny endogenously-expressed molecules that fine-tune gene expression through several different mechanisms.² In the case of haematological malignancies, profiling of microRNA expression has been shown to correlate with cytogenetic changes, somatic mutations and clinical outcomes in acute myeloid leukaemia, chronic myeloid leukaemia, chronic lymphocytic leukaemia and lymphoma.

Synchronous Gastrointestinal Stromal Tumor and Adenocarcinoma at the Gastroesophageal Junction

The synchronous existence of two different tumors in the gastrointestinal tract is uncommon. We report the case of a 75-year-old man who had a concurrent gastrointestinal stromal tumor and adenocarcinoma at the gastroesophageal junction. The two tumors arose at the same site but had distinct morphologies. The etiology of synchronous tumors is still unclear and their coexistence causes problems for the surgeon, oncologist and pathologist in terms of their diagnosis, treatment, and follow-up. We report a rare case of synchronous tumors and a review of the literature.

Advanced differentiation in trichoepithelioma and basal cell carcinoma investigated by immunohistochemistry against neurofilaments.

Basal cell carcinoma (BCC) and trichoepithelioma (TE) are sometimes diagnostic challenges for the pathologist in terms of their differential diagnosis. Although literature is quite rich in information about histologic and immunohistochemical clues to distinguish the differences between both, no single finding must be completely reliable. Moreover, some consider that TE is a better differentiated follicular tumour, while BCC represents a less developed stage in differentiation. For instance, the latter opinion is supported by the evidence of follicular papillae in TE.The formation of a perifollicular nerve plexus happens later than the formation of the follicular papillae in the development of a normal follicle. The study of the presence of the perifollicular nerve plexus in both tumours which could then provide us with evidence on the stage of differentiation of both tumours. 5 cases of TE and 10 cases of BCC were randomly selected from our archives and an immunohistochemical study for neurofilaments was performed in all the cases.We found a peritumoural nerve plexus in all the cases (TEs and BCCs). Since this plexus is a late sign of differentiation and since both types of neoplasias share it, we conclude that TE and BCC are both terminally differentiated neoplasms. The ability of BCC to infiltrate would have more to do with the acquisition by the tumour of such a property, rather than with a stage of indifferentiation.

Local resection of malignant lesions of the hip and pelvis. 1966.

Local resection of malignant lesions of the hip and pelvis. 1966.