Samreung Rangdaeng

Global Gene Expression Profile of Nasopharyngeal Carcinoma by Laser Capture Microdissection and Complementary DNA Microarrays

A number of genetic and epigenetic changes underlying the development of nasopharyngeal carcinomas have recently been identified. However, there is still limited information on the nature of the genes and gene products whose aberrant expression and activity promote the malignant conversion of nasopharyngeal epithelium. Here, we have performed a genome-wide transcriptome analysis by probing cDNA microarrays with fluorescent-labeled amplified RNA derived from laser capture microdissected cells procured from normal nasopharyngeal epithelium and areas of metaplasia-dysplasia and carcinoma from EBV-associated nasopharyngeal carcinomas. This approach enabled the identification of genes differentially expressed in each cell population, as well as numerous genes whose expression can help explain the aggressive clinical nature of this tumor type. For example, genes indicating cell cycle aberrations (cyclin D2, cyclin B1, activator of S-phase kinase, and the cell cycle checkpoint kinase, CHK1) and invasive-metastatic potential (matrix metalloproteinase 11, v-Ral, and integrin β4) were highly expressed in tumor cells. In contrast, genes underexpressed in tumors included genes involved in apoptosis (B-cell CLL/lymphoma 6, secretory leukocyte protease inhibitor, and calpastatin), cell structure (keratin 7 and carcinoembryonic antigen-related cell adhesion molecule 6), and putative tumor suppressor genes (H-Ras-like suppressor 3, retinoic acid receptor responder 1, and growth arrested specific 8) among others. Gene expression patterns also suggested alterations in the Wnt/β-catenin and transforming growth factor β pathways in nasopharyngeal carcinoma. Thus, expression profiles indicate that aberrant expression of growth, survival, and invasion-promoting genes may contribute to the molecular pathogenesis of nasopharyngeal carcinoma. Ultimately, this approach may facilitate the identification of clinical useful markers of disease progression and novel potential therapeutic targets for nasopharyngeal carcinoma.

Lymphadenopathy due to Penicillium marneffei infection: Diagnosis by fine needle aspiration cytology

Penicillium marneffei is an opportunistic fungal infection that usually causes disseminated disease, mainly in immunocompromised individuals, especially those with HIV infection. Untreated cases are usually fatal. Diagnosis is traditionally made by biopsy and/or culture; successful diagnosis by fine needle aspiration (FNA) has only been reported once. We present eight cases of HIV-infected patients with lymphadenopathy caused by P. marneffei infection, in which the diagnosis was made by FNA. In all cases, intracellular and extracellular yeast forms were visualized, and the characteristic cross-septation of P. marneffei was highlighted by GMS staining. All diagnoses were confirmed by culture. Anti-fungal treatment for P. marneffei was initiated, resulting in marked clinical improvement. We conclude that a diagnosis of lymphadenopathy caused by P. marneffei can reliably be made by FNA. The diagnosis is more rapid than biopsy or culture, allowing rapid institution of therapy, particularly important in immunocompromised patients. In all our cases, not only were lymphoma and other causes of lymphadenopathy ruled out, but also the necessity for an open surgical biopsy was obviated. This can be especially beneficial to patients (e.g., three in our study) in which lymphadenopathy is confined to deep intra-abdominal nodes.

Skin blister immunocytology A new method to quantify cellular kinetics in vivo

A method is described using tuberculin purified protein derivative (PPD) as a model to follow the in vivo cellular immune response. This combines induction of a local response, formation of skin blisters, and staining of the cells appearing in the sterile exudate over time, using standard cytopreparatory and immunoperoxidase techniques. Skin blisters were induced over sites previously injected intradermally with PPD or control saline using suction over a template on the forearm. The cells which appeared in the exudate at 24, 36, 48 and 72 h were collected on small cellulose filters which were divided into several parts. The cells on the filter segments were then stained using a biotin-avidin immunoperoxidase method with a panel of monoclonal antibodies, and with enzyme histochemical techniques. This allowed quantitative estimation over an extended period of total numbers of each cell type responding as a local expression of cellular immunity. The kinetics of an early, non-specific inflammatory response could be distinguished from the later immune response using total cell counts. Maximal cell counts correlated well with PPD induced induration at 48 h, showing an overwhelming predominance of mononuclear cells. Over 72 h, the number of non-specific esterase (NSE) positive cells (macrophage) declined while Leu4 positive cells (T cells) increased. OKT4 positive cells (T helper) outnumbered OKT8 positive cells (T suppressor) as the response developed. This method enables the direct quantitative assessment of cell populations arriving at the site of an immune response using a simple inexpensive technique which is painless, non-invasive and non-scarring.

Angiostrongylus cantonensis infection mimicking a spinal cord tumor

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis and meningoencephalitis. Almost all cases are self‐limiting and are diagnosed by cerebrospinal fluid eosinophilia and enzyme‐linked immunosorbent assay; pathology reports are restricted to postmortem samples from lethal cases. We report on what we believe is the first case of A. cantonensis infection diagnosed by biopsy in a living patient. The spinal cord was biopsied because of the unusual clinical presentation of a myelopathy without meningeal symptoms, together with a mass lesion that was clinically and radiologically diagnosed as a spinal cord tumor.

Current Status of Thyroid Fine-Needle Aspiration Practice in Thailand

Thyroid carcinoma is one of the leading malignancies in Thailand increasingly prevalent in the female population. Fine-needle aspiration (FNA) cytology is a widely used diagnostic tool for evaluation of thyroid nodules and thyroid cancer. Thyroid FNA is a routine procedure universally performed in Thai hospitals by a variety of clinical specialists. Manual guidance is the first-line choice complemented by ultrasound assistance in selected cases. Despite national guidelines recommendations, the diagnostic criteria and terminology of the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was slowly adopted in the local settings. Currently, the Bethesda system is actively promoted by the local professional societies as a uniform reporting system. Experience with thyroid FNA has been rarely reported to date—only a handful of publications are available in local journals. Our review, in addition to presenting various aspects of thyroid FNA in Thailand, established for the first time national references for a certain statistical outputs of TBSRTC based on the original multi-institutional cohort. The risk of malignancy in 2,017 operated thyroid nodules collected from three tertiary thyroid cancer centers was 21.7%, 14.7%, 35.9%, 44.4%, 76.7%, and 92.6% for categories I to VI, respectively. The malignancy risk in several diagnostic categories (II to IV) was higher than the risk estimated by TBSRTC and recent meta-analysis studies. We endorse the use of uniform terminology of the Bethesda system in Thailand, which will help facilitate communication among diverse medical professionals involved in the management of patients with thyroid nodules, to share local experience with the international audience.

False-Negative Rate of Papanicolaou Testing: A National Survey from the Thai Society of Cytology

Objective: To evaluate the performance of Papanicolaou smear screening in Thailand at the national level, and to propose recommendations for continuing quality control. Study Design: This study was conducted by The Thai Society of Cytology and involved 124 laboratories in 76 provinces during 2010-2014. Random sampling suggested recalling of 10% of slides defined as negative at routine screenings (10% random rescreening [R10] model) directly from the reading unit. Results: Out of 330,075 smears covered by the rescreening project throughout its 5-year duration, the rates of abnormal, unsatisfactory, and normal results were 0.63, 1.82, and 97.55%, respectively. Abnormal findings were largely represented by ASC-US (54%) and L-SIL (21%). The average false-negative rate (FNR) measured at the level of L-SIL and higher was 13.8%. Conclusion: The national project was developed to address the accuracy of cervical cancer screening and to promote internal quality assurance based on the R10, on-site surveys, and education. The major output parameters of this study (FNR and number and distribution of abnormal cases on rescreening) improved significantly in the main phase of the project (2012-2014), after revising substantial logistics issues encountered during the first 2 years of this study. This project provided objective measurable evidence related to the quality of cytology-based cervical cancer screening in Thailand.

Changes in peripheral innervation and nociception in reticular type and erosive type of oral lichen planus

BACKGROUND Oral lichen planus (OLP) is a chronic inflammatory lesion in oral mucosa. Reticular (OLP-R) and erosive (OLP-E) types of OLP are the common forms that have been found in dental clinics. The aim of this investigation is to determine the correlation between neurogenic inflammation and nociception associated with OLP-R and OLP-E. MATERIALS AND METHODS The oral mucosal lesions from six patients with OLP-E, four with OLP-R and three with noninflamed oral mucosa, which represent normal mucosa, were identified by morphometric analysis of nerve fibers containing immunoreactive protein gene product (PGP) 9.5. The level of inflammation was measured with hematoxylin and eosin staining and the level of nociception was analyzed with visual analog scale measurement. RESULTS We found that 1) an increase in peripheral innervation was related to the size of the area of inflammatory cell infiltration from both OLP-R and OLP-E; 2) the pattern of PGP 9.5-immunoreactivity among OLP-R and OLP-E was not significantly different (P=0.23); and 3) the correlation between nociception and an increase in PGP 9.5-immunoreactivity was not found in OLP-E and in OLP-R. CONCLUSIONS Our findings suggest that an increase in peripheral innervation may lead to increased inflammation, which is part of the immunopathogenesis of OLP. Differences in nociception between OLP-R and OLP-E arise from the pathogenesis of each lesion, not from the differences in peripheral innervation.