Hyung Sik Shin

Expression profiles of p63, p53, survivin, and hTERT in skin tumors

Background:  p63 is a p53 homolog and a marker expressed in replicating keratinocytes. Survivin is a recently characterized inhibitor of apoptosis protein that is abundantly expressed in most solid and hematologic malignancies. Telomerase reverse transcriptase (TERT) is the major determinant of human telomerase activity, and its expression is indicative of unlimited replication. We herein evaluated the expression profiles of p63, p53, survivin, and hTERT in usual skin cancers, including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) and putative preneoplastic epidermal lesions, including actinic keratosis (AK), Bowens diasease, and porokeratosis.

Foregut duplication cyst of the stomach

Foregut duplication cyst of the stomach is an extremely rare disease entity. A 35‐year‐old Korean man presented with epigastric pain. An abdominal cystic mass, measuring 7 × 6 × 5 cm, was found in the lesser curvature of the stomach. The cyst was unilocular with a grey‐white, rubbery wall. Microscopically, the cyst wall was lined by pseudostratified ciliated, columnar epithelium and gastric mucosa with a complete lining of smooth muscle bundles. Although the origin of this lesion remains uncertain, this case suggests that the gastric cyst arose from the embryonic foregut and showed differentiation toward respiratory and gastric structures.

Helicobacter pylori infection and the risk of gastric cancer among the Korean population

Helicobacter pylori infection has been associated with chronic atrophic gastritis, a precursor of gastric cancer. We conducted a prospective, case‐controlled study to investigate whether H. pylori infection increases the risk of gastric cancer in Korean people with a high risk of gastric cancer. We enrolled 160 gastric cancer patients who were confirmed by endoscopic biopsy during 1994 and 160 age‐matched control subjects with non‐ulcer dyspepsia were compared to document the relationship between H. pylori infection and gastric cancer. The presence of H. pylori infection was determined by the rapid urease test and/or histology by Wright‐Giemsa staining. The overall presence of H. pylori infection was 60% in gastric cancer patients and 51.9% in age‐matched control subjects (odds ratio 1.39; 95% confidence interval 0.894–2.17; P= 0.143). Carcinomas of cardia, body and antrum were not associated with H. pylori infection (odds ratio 1.43, 1.69 and 1.29, respectively; 95% confidence interval, 0.271–7.52, 0.787–3.62 and 0.689–2.43, respectively; P= 0.178, 0.177 and 0.642, respectively) nor was the intestinal or diffuse type of cancer (odds ratio 1.39 and 1.40, respectively; 95% confidence interval 0.791–2.45 and 0.681–2.87, respectively; P= 0.250 and 0.835, respectively). Gender was not a risk for gastric cancer. In contrast to previous studies, these results do not provide evidence of H. pylori infection for gastric carcinogenesis in Korea.

Fine needle aspiration Cytologic findings of breast mucinous neoplasms : Differential diagnosis between mucocelelike tumor and mucinous carcinoma

OBJECTIVE To report the cytologic findings of mucocelelike tumor and mucinous carcinoma. STUDY DESIGN All mucinous neoplasms diagnosed by fine needle aspiration and confirmed by histologic examination were reviewed to detect the cytologic findings helpful for the differentiation. The cytologic findings were correlated with the histologic findings. RESULTS Cytologically, mucinous carcinomas were highly cellular and showed many single epithelial cells and variably formed epithelial cell clusters in abundant extracellular mucin. Malignant cells exhibited round, atypical nuclei; granular chromatin; and small nucleoli. Mucocele like tumor showed low cellularity with scanty, monolayered, small sheets of epithelial cells and abundant, extracellular mucin. Myoepithelial cells were present within the epithelial cell sheets. Tumor cells were usually small, with uniform, round nuclei; fine chromatin; and absence of nucleoli. CONCLUSION Cytologic findings of mucocelelike tumor and mucinous carcinoma were different in cellularity, shape of cell clusters and nuclear features, although mucocelelike tumors having a carcinoma component were similar to mucinous carcinoma. Awareness of the cytologic findings of breast mucinous neoplasms is important to make a specific diagnosis.

High mobility group HMGI(Y) protein expression in head and neck squamous cell carcinoma

Conclusion. We conclude that increased expression level of the high mobility group I (HMGI(Y)) is closely associated with malignant transformation in head and neck squamous cell carcinomas (HNSCCs), and the measurement of HMGI(Y) levels in HNSCCs may be useful as a prognostic marker. Objectives. To investigate whether HMGI overexpression is observed in HNSCCs, and its value as a prognostic marker in HNSCCs. Materials and methods. HMGI(Y) expression was determined at the protein level by immunohistochemisty using a HMGI(Y)-specific antibody and RT-PCR in 10 surgically resected specimens of non-neoplastic tissue (normal palatal tissue) and 40 HNSCCs. We also evaluated the association of HMGI(Y) overexpression within clinicopathologic parameters, i.e. clinical stage, pathologic grade, status of cervical lymph node metastasis, recurrence rate. Results. Expression of HMGI(Y) by immunohistochemical staining was observed in 35 of 40 (87.5%) HNSCC samples, whereas normal mucosa and/or the mucosa adjacent to the tumor tissue showed negative or weakly positive staining (p<0.05). Semi-quantification of HMGI(Y) by RT-PCR was 2.98±2.24 in cancer and 0.47±0.25 in normal tissue (p<0.001). High expression of HMGI(Y) was observed in recurrent cases, compared with non-recurrent cases (p<0.05). However, no significant correlation was observed between the levels of HMGI(Y) expression and other clinical factors such as clinical stage, pathologic grade, and status of cervical lymph node metastasis.

Expression of the HMGI(Y) gene in human colorectal cancer

Expression of HMGI(Y), a nucleoprotein that binds to A/T rich sequences in the minor groove of the DNA helix, is observable in neoplastically transformed cells but not in normal cells. We have analyzed HMGI(Y) expression in colorectal cancer and evaluated its clinicopathologic significance. HMGI(Y) mRNA was measured by CRT‐PCR (competitive reverse transcription‐polymerase chain reaction). Immunohistochemical staining for HMGI(Y), p53 and Ki‐67 was performed in the same colon cancer tissues, and the results in colorectal tissues were similar to those of RT‐PCR. HMGI(Y) expression evidenced by RT‐PCR was observed in 63 of 64 (98.4%) colorectal cancer samples, and 2 of 5 (40%) adenomatous polyps, whereas 21 normal colon samples were negative (p<0.001). High HMGI(Y) expression using CRT‐PCR was found in colon cancers with a high Ki‐67 labeling index (p<0.001). There was no significant correlation between the levels of HMGI(Y) expression and stage, tumor size, lymph node metastasis, histologic grade and immunohistochemical status of p53. Our results indicate that the HMGI(Y) expression may occur at an early stage of carcinogenesis and correlate with cell proliferation. Int. J. Cancer (Pred. Oncol.), 84:376–380, 1999.

Ciliated foregut cyst of the gallbladder: A case report and review of the literature

A case is presented of a ciliated cyst of the gallbladder in a 36‐year‐old Korean woman which was incidentally found on ultrasonographic study. A cystic mass measuring 1.5 × 1 × 1 cm was found in the fundus of the gallbladder. The cyst was unilocular and intramural without communication to the lumen. Microscopically, the cyst wall was lined by a single layer of pseudostratified, ciliated, columnar epithelium and goblet cells with underlying smooth muscle layers. This was considered to be the cyst arising from the embryonic foregut and showing differentiation toward respiratory structures. The term ‘ciliated foregut cyst of the gallbladder’ is suggested here.

Low frequency of KRAS mutation in pancreatic ductal adenocarcinomas in Korean patients and its prognostic value.

Objectives Low prevalence and prognostic relevance of KRAS mutations in Korean pancreatic ductal adenocarcinomas (PDACs) need to be validated with sensitive detection method. Methods Peptide nucleic acid (PNA)–mediated polymerase chain reaction (PCR) clamping was used to precisely detect KRAS mutation in 72 paraffinized tumor samples and was validated by pancreatic cell lines to compare the efficiency of direct sequencing. Results The PNA-mediated PCR clamping detected mutant allele proportions of as low as 0.5% against a background of wild-type DNA and was 20-fold more sensitive than direct sequencing through the validation of pancreatic cell lines. Peptide nucleic acid–mediated PCR clamping detected KRAS mutations in 47.2% of 72 PDACs. Low tumor cellularity and low PCR amplification efficiency led to be undetected or failed by direct sequencing in pancreatic paraffinized samples. KRAS mutations were an independent worse prognostic factor predicting a reduced progression-free survival rate in the postoperative chemotherapy group. Conclusions Peptide nucleic acid clamp real-time PCR was a sensitive method for detecting KRAS status in paraffinized PDAC samples. We identified a low KRAS mutation rate among the Korean PDAC patients using PNA clamp real-time PCR, potentially implicating epidemiological characteristics. The low KRAS mutation rate and its prognostic role may suggest the further survival benefit in Korean PDAC patients.

Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of the Thymus Case Report and Literature Review

We present a rare case of primary low-grade B-cell lymphoma of the thymus. The tumor showed the typical features of a MALT (mucosa-associated lymphoid tissue) lymphoma with epithelium-lined thymic cyst. Histologically, there were sheets of centrocyte-like (CCL) cells intermingled with small lymphocytes and plasma cells. CCL cells invaded the epithelium of the cyst and residual Hassalls corpuscles, forming characteristic lymphoepithelial lesions. Immunohistochemically, the tumor cells revealed positive immunoreaction for CD20 and monotypic cytoplasmic restriction of kappa light chain.

Histopathologic Predictors of Lymph Node Metastasis and Prognosis in Tonsillar Squamous Cell Carcinoma

Background Risk factors for lymph node metastasis in tonsillar squamous cell carcinoma (TSCC) need to be established to determine the degree of surgery required to achieve high curative rates. However, little is known currently about the histopathological features predicting prognosis, specifically in TSCC. Methods This study included 53 patients who underwent surgical resection with neck dissection. Clinicopathological factors investigated included age, gender, alcohol use, tobacco consumption, tumor stage, adjacent structure involvement, cell differentiation, squamous dysplasia, in situ carcinoma associated with primary invasive cancer, carcinoma in situ skip lesions, necrosis, invasive front, depth of invasion, and lymphatic, muscle, or perineural invasion. Results Contralateral cervical metastasis was associated with higher T stages and soft palate invasion. Lymphatic and muscle invasion were associated with ipsilateral cervical metastasis. Advanced T stage, invasion to the base of tongue, and skip lesions were associated with decreased disease-free survival. Advanced T stage and skip lesions were associated with worse overall survival. Conclusions Advanced T stage and soft palate invasion may predict a high risk of contralateral nodal metastasis. T stage and skip lesion are worse prognostic factors in TSCC and should be commented in pathology reports.