Woon Yong Jung

Paradoxical high signal intensity of hepatocellular carcinoma in the hepatobiliary phase of Gd-EOB-DTPA enhanced MRI: initial experience

PURPOSE To describe the paradoxical high signal intensity of hepatocellular carcinoma (HCC) in the hepatobiliary phase on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI). MATERIALS AND METHODS A database search was performed to identify cases of HCC that showed unusual prolonged enhancement in the hepatobiliary phase of Gd-EOB-DTPA MRI. All patients received 3.0-T liver MRI including precontrast T1-weighted images, T2-weighted images and a post Gd-EOB-DTPA-enhanced dynamic study. The signal intensity of HCC was measured at pre-enhanced, arterial, portal, delayed and hepatobiliary phase using regions of interest. Radiologic and pathologic correlation was performed for the paradoxically prolonged enhancing portion of HCC in the hepatobiliary phase. RESULTS Four patients (all male, age range 44-70; mean 57.5 years) were included in this study. All patients showed HCC lesions that were low signal intensity (SI) on T1-WI, high SI on T2-WI, enhanced in arterial phase, and washed-out in delayed phase. All cases showed paradoxically high SI in hepatobiliary phase, which was unusual for HCC. Pathologically, they were all diagnosed as well-differentiated HCC with prominent cytoplasm and a bile secreting appearance. CONCLUSION HCC may demonstrate the prolonged high signal intensity at the hepatobiliary phase on Gd-EOB-DTPA enhanced MRI. These HCCs tended to be highly differentiated and to have prominent bile secretion.

SIRT1 Expression Is Associated with Good Prognosis in Colorectal Cancer

Background Silent mating type information regulation 2 homolog 1 (SIRT1), an NAD+-dependent deacetylase, might act as a tumor promoter by inhibiting p53, but may also as a tumor suppressor by inhibiting several oncogenes such as β-catenin and survivin. Deleted in breast cancer 1 (DBC1) is known as a negative regulator of SIRT1. Methods Immunohistochemical expressions of SIRT1, DBC1, β-catenin, surviving, and p53 were evaluated using 2 mm tumor cores from 349 colorectal cancer patients for tissue microarray. Results Overexpression of SIRT1, DBC1, survivin, and p53 was seen in 235 (67%), 183 (52%), 193 (55%), and 190 (54%) patients, respectively. Altered expression of β-catenin was identified in 246 (70%) patients. On univariate analysis, overexpression of SIRT1 (p=0.029) and altered expression of β-catenin (p=0.008) were significantly associated with longer overall survival. Expression of SIRT1 was significantly related to DBC1 (p=0.001), β-catenin (p=0.001), and survivin (p=0.002), but not with p53. On multivariate analysis, age, tumor stage, differentiation, and expression of SIRT1 were independent prognostic factors significantly associated with overall survival. Conclusions SIRT1 overexpression is a good prognostic factor for colorectal cancer, and SIRT1 may interact with β-catenin and survivin rather than p53.

Expression of moesin and CD44 is associated with poor prognosis in gastric adenocarcinoma

CD44 has been reported as a negative prognostic marker in gastric cancer. It interacts with moesin in epithelial–mesenchymal transition. To date, to our knowledge, there has been no clinical study dealing with the relationship between moesin and gastric adenocarcinoma. We analysed the expression of moesin and CD44 in gastric adenocarcinoma tissue, and correlations with clinicopathological factors.

NOVA1 inhibition by miR-146b-5p in the remnant tissue microenvironment defines occult residual disease after gastric cancer removal

Occult residual disease in remnant tissues could be the cause of tumor relapse. To identify signal molecules and target cells that may be indicative of occult residual disease within a remnant microenvironment, proximal resection margin tissues of gastric cancers were used, as these correspond to the nearest remnant tissues after gastrectomy. Increased miR-146b-5p in the remnant microenvironment was determined to be a strong risk factor for tumor relapse and poor survival rate. NOVA1, a target gene of miR-146b-5p, was decreased in remnant tissues of patients with a poor prognosis. NOVA1 was enriched in stromal spindle cells such as fibroblasts within normal tissues. In non-neoplastic inflammation, such as gastritis, NOVA1 was highly enriched in T lymphocytes and stromal spindle cells, while expression of this protein was frequently decreased in those types of cells within gastric cancer tissues. Particularly, decreased NOVA1 in T cells within the gastric cancer tissues was correlated with decreased FOXP3-positive regulatory T cells and was associated with poor patient prognosis. In vitro analysis showed that the NOVA1 gene was inhibited by miR-146b-5p. In immune cells as well as stromal spindle cells, decreased NOVA1, possibly inhibited by miR-146b-5p, is a candidate biomarker predicting poor prognosis of gastric cancer patients and is also a biomarker of occult residual disease in remnant tissues after gastric cancer removal.

NK/T-Cell Lymphoma Associated with Epstein-Barr Virus in a Patient Infected with Human Immunodeficiency Virus: An Autopsy Case

Natural killer (NK)/T-cell lymphoma associated with Epstein-Barr virus (EBV) in a patient infected with human immunodeficiency virus (HIV) is very rare. The authors encountered a case of NK/T-cell lymphoma in a 36-year-old man who presented with an ulcerative mass on both tonsils. During assessment, HIV positivity was noted. The EBV was detected by EBV-encoded RNA 1 messenger RNA in situ hybridization and polymerase chain reaction for EBV-encoded nuclear antigen 1. On immunohistochemical staining, the infiltrated lymphoid cells of the tonsils demonstrated positvity for CD3, CD56, UCHL1, and granzyme, a finding compatible with NK/T-cell lymphoma. The patient received radiation therapy and chemotherapy, but died as a result of opportunistic infection of invasive aspergillosis after tumor recurrence. An autopsy was done with the consent of the patient’s family. To our knowledge, this is the first case in an HIV patient of NK/T-cell lymphoma of the tonsils associated with EBV, confirmed by autopsy. NK/T-cell lymphoma should be considered in the HIV-positive patients with an ulcerating tonsillar mass. doi: 10.1532/IJH97.A10316

Giant Endocervical Polyp Mimicking Cervical Malignancy: Primary Excision and Hysteroscopic Resection

Giant cervical polyps are characterized by an unusually large size and appear clinically as malignant. A 35-year-old woman had increased vaginal discharge and lower abdominal discomfort. At examination, a fist-sized, hard, consistent mass was found in the vagina. Pelvic magnetic resonance imaging revealed a 12.6 x 8-cm solid tumor with internal papillary growth within the entire vaginal cavity. The tumor base was suspected to have originated from the endocervix by a connecting stalk. Primary excision of the tumor was performed via the vagina, and the remnant tissue was completely removed at hysteroscopic resection. The final histopathologic findings confirmed a benign giant cervical polyp.

Acyl-CoA thioesterase 8 is a specific protein related to nodal metastasis and prognosis of lung adenocarcinoma

Metastasis is a major cause of cancer recurrence or death. This study attempted to quantitatively identify different proteins in metastatic lung adenocarcinoma. The N/T quotient [number of metastatic lymph nodes (n)/tumor diameter (cm)] was used to select samples with an extreme metastatic phenotype. Among the six fresh frozen lung adenocarcinoma specimens, the three showing the highest N/T quotient represented the metastatic group, and others with the greatest tumor diameters without metastasis represented the non-metastatic group. After 2-dimensional electrophoresis, the significantly different protein spots were selected by image analysis and analyzed with MALDI-TOF mass spectrometry. Acyl-CoA thioesterase 8 isoform c (ACOT8) was one of most overexpressed proteins in the metastatic group, and it was validated by Western blot and immunohistochemical staining on 108 paraffin-embedded tumor samples. High ACOT8 expression was correlated with lymph node metastasis (p=0.002), recurrence (p=0.034), predominant histologic subtypes (p=0.007), and higher stage (p=0.005). In multivariate analysis, high ACOT8 expression was significantly associated with increased risks of lymph node metastasis (p=0.009) and cancer-related death (p=0.030), independent of clinical factors. ACOT8 may be a candidate prognostic biomarker and therapeutic target of lung adenocarcinoma.

Prognostic Significance of Heat Shock Protein 70 Expression in Early Gastric Carcinoma

Background Overexpression of heat shock protein 70 (HSP70) has been observed in many types of cancer including gastric adenocarcinomas, although the exact role of HSP70 in carcinogenesis remains unclear. Methods The study analyzed a total of 458 radical gastrectomy specimens which were immunohistochemically stained with HSP70, p53, and Ki-67 antibodies. Results The study determined that the expression of HSP70 was significantly increased in early gastric cancer (EGC) compared to advanced gastric cancer (p<0.001). The HSP70 expression was correlated with well-differentiated tumor type, intestinal type of Lauren classification and the lower pT and pN stage. Negative expression of Ki-67 and p53 expression was associated with poor prognosis. The study did not find any correlation between HSP70 and p53 expression. The study determined that HSP70 expression in the EGC subgroup was associated with a poor prognosis (p=0.009), as well as negative Ki-67 expression (p=0.006), but was not associated with p53. Based on multivariate analysis, HSP70 expression (p=0.024), negative expression of Ki-67, invasion depth and lymph node metastasis were determined to be independent prognostic markers. Conclusions HSP70 is expressed in the early stages of gastric adenocarcinoma. In EGC, HSP70 is a poor independent prognostic marker and is correlated with a low proliferation index.

Pigmented Perivascular Epithelioid Cell Tumor (PEComa) of the Kidney: A Case Report and Review of the Literature

Heavily pigmented perivascular epithelioid cell tumors (PEComa) are rare, only eight cases of which have been reported. Unlike typical epithelioid angiomyolipoma, most of these tumors have been encountered in female patients without tuberous sclerosis. The long-term prognosis thereof is undetermined. Cytological similarity and heavy melanin pigment make it difficult for pigmented PEComa to be differentiated from pigmented clear cell renal cell carcinoma or malignant melanoma. The immunoprofile of tumor cells, such as human melanoma black-45 expression, as well as the absence or presence of other melanocytic or epithelial markers, are helpful in determining a differential diagnosis. Here we report a case of heavily pigmented PEComa of the right kidney and review the literature describing this tumor. In this case, the immunoprofile and clinical features corresponded well to those described in the literature. Since the prognosis of such disease has not yet been established, close follow-up of this patient was recommended.