Cystic Primary Hepatic Neuroendocrine Tumor.

Neuroendocrine tumors (NETs) can arise throughout the body. Most NETs in the liver are metastatic tumors; primary hepatic NET (PHNET) is extremely rare. A diagnosis of PHNET is very difficult. No single modality can diagnose PHNET by itself, and it often resembles other hypervascular masses of the liver. This paper reports the case of a 51-year old female with a large hepatic mass. Unlike most of PHNETs reported previously, it was composed of a solid mass with mainly multiple cystic lesions, which led to an erroneous diagnosis of hepatic mucinous cystadenoma or cystadenocarcinoma. PHNET with cystic lesions is extremely rare, and the features are not well studied. This case may help physicians suspect PHNET in a differential diagnosis of an atypical hepatic mass.

Colonic Metastasis Presenting as an Intraluminal Fungating Mass 8 Years After Surgery for Ovarian Cancer.

We report a case of colonic metastasis from ovarian cancer presented as an intraluminal fungating mass mimicking primary colon cancer 8 years after surgery for ovarian cancer. A 70-year-old woman presented with constipation. She had undergone an extended total abdominal hysterectomy with bilateral salpingo-oophorectomy for an ovarian papillary serous cystadenocarcinoma 8 years earlier. Colonoscopy showed a large fungating mass 10 cm from the anal verge that was suspected to be colorectal cancer. A computed tomography scan showed a bulky intraluminal fungating mass in the rectosigmoid junction. After a lower anterior resection and a pathologic diagnosis, a diagnosis of a papillary serous adenocarcinoma due to metastasis from an ovarian tumor was made for this patient.

Pathological Predictors for Defining a Therapeutic Strategy for Early Colon Cancer after Endoscopic Resection: Multicenter Retrospective Analysis from Surgically Resected Specimens.

BACKGROUND/AIMS: For the possibility of regional lymph node metastasis (LNM), early colon cancer (ECC) is a boundary lesion between endoscopic resection and surgery. The aim of study is to clarify risk factors for LNM and to determine therapeutic strategy after endoscopic resection in patients with ECC. METHODOLOGY: The histopathology of patients with ECC underwent surgery with LN dissection in 8 university hospitals were reviewed by experienced pathologist blinded to LN status. RESULTS: In total, 370 patients (107 with mucosal cancer, 263 with submucosal invasive colorectal carcinoma [SICC]) were enrolled. Excluding mucosal cancer, the LNM rate was 11.8% (31/263, including 15.4% [8/52] with pedunculated SICC [P-SICC] and 10.9% [23/211] with non-pedunculated SICC [NP-SICC]). Multivariate analysis showed that tumor sprouting (P < 0.001; odds ratio [OR], 8.83; 95% confidence interval [CI], 3.04-25.69), submucosal invasion depth (SM depth) > 2000 µm (P = 0.024; OR, 3.68; 95% CI, 1.19-11.37), and lymphatic invasion (P = 0.022; OR, 3.48; 95% CI, 1.19-10.13) were related to LNM. All LNMs with SM depth < 2000 µm showed tumor sprouting without lymphatic invasion. CONCLUSIONS: Significant risk factors for predicting LNM in patients with SICC were tumor sprouting, SM depth > 2000 µm, and lymphatic invasion.

Incremental value of cell block preparations over conventional smears alone in the evaluation of EUS-FNA for pancreatic masses.

BACKGROUND/AIMS: The effectiveness of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been established for a definite pathological diagnosis of pancreatic solid masses. We investigated the usefulness of cell block preparations in EUS-FNA, by evaluating the added value of cell block preparations over conventional smears alone. METHODOLOGY: Between March 2011 and June 2013, 61 patients were retrospectively evaluated who underwent EUS-FNA for pancreatic solid masses. Diagnostic values for diagnosing pancreatic malignancy were compared for a combination of the conventional smear and cell block (CSCB) and the conventional smear alone (CS). RESULTS: The addition of the cell block technique increased the sensitivity of conventional smear for diagnosing the pancreatic malignancy from 79% (CS) to 90% (CSCB, p=0.0313) and the accuracy from 81% to 91% (p=0.0313). The specificity and positive predictive value were 100% in both methods. The negative predictive value was increased from 33% (CS) to 50% (CSCB), but this difference was not statistically significant (p=0.0833). CONCLUSION: The addition of the cell block method after a conventional smear may increase the sensitivity and negative predictive value for diagnosing the pancreatic malignancy in patients with pancreatic masses who undergo EUS-FNA. Further study may be warranted to determine whether the cell block method can replace the conventional smear.

Early colorectal epithelial neoplasm in Korea: a multicenter survey of pathologic diagnosis.

BACKGROUND: The incidence of early colorectal epithelial neoplasm (ECEN) is increasing, and its pathologic diagnosis is important for patient care. We investigated the incidence of ECEN and the current status of its pathologic diagnosis. METHODS: We collected datasheets from 25 institutes in Korea for the incidence of colorectal adenoma with high grade dysplasia (HGD) and low grade dysplasia in years 2005, 2007, and 2009; and early colorectal carcinoma in the year 2009. We also surveyed the diagnostic terminology of ECEN currently used by the participating pathologists. RESULTS: The average percentage of diagnoses of adenoma HGD was 7.0%, 5.0%, and 3.4% in years 2005, 2007, and 2009, respectively. The range of incidence rates of adenoma HGD across the participating institutes has gradually narrowed over the years 2005 to 2009. The incidence rate of early colorectal carcinoma in the year 2009 was 21.2%. The participants did not share a single criterion or terminology for the diagnosis of adenoma HGD. The majority accepted the diagnostic terms that distinguished noninvasive, mucosal confined, and submucosal invasive carcinoma. CONCLUSIONS: Further research requirements suggested are a diagnostic consensus for the histopathologic diagnosis of ECEN; and standardization of diagnostic terminology critical for determining the disease code.

Update on the proposal for creating a guideline for cancer registration of the gastrointestinal tumors (I-2).

BACKGROUND: Cancer registries play a fundamental role in cancer control and multicenter collaborative research. Recently, the need for reassessment of cancer registry criteria has arisen due to the newly released 2010 World Health Organization (WHO) classification. Accordingly, development of new coding guidelines for cancer is necessary to improve the quality of cancer registries, as well as to prevent conflicts that may arise when seeking medical insurance compensation. METHODS: With funding from the Management Center for Health Promotion, 35 members of the Gastrointestinal Pathology Study Group and the Cancer Registration Committee of the Korean Society of Pathologists (KSP) participated in a second workshop for gastrointestinal tumor registration in Korea. RESULTS: The topics of gastric epithelial tumor, colonic intramucosal carcinoma, neuroendocrine tumor (NET), gastrointestinal stromal tumor (GIST) and appendiceal mucinous tumor were discussed for new coding guidelines. A survey was then conducted among 208 members of the KSP for a consensus of the guidelines proposed in the workshop. CONCLUSIONS: Although a few issues were set aside for further discussion, such as coding for non-gastric GIST and some types of NET, the members agreed upon most of the proposed guidelines. Therefore, we suggest using the newly revised International Classification of Diseases for Oncology, 3rd edition (ICD-O-3) coding guidelines for registering gastrointestinal tumors in Korea.

Biologic correlation between glucose transporters, hexokinase-II, Ki-67 and FDG uptake in malignant melanoma.

INTRODUCTION: The purpose of this study was to investigate the correlative association between tumoral 2-deoxy-2-[(18)F]-fluoro-D-glucose (FDG) uptake, and the expressions of glucose transporter 1 (GLUT-1), glucose transporter 3 (GLUT-3), hexokinase II (HK-2), and Ki-67 expression in malignant melanoma. METHODS: Nineteen patients with histologically proven malignant melanoma and pretreatment FDG PET/CT performance were involved in this preliminary study. For semi-quantitative analysis of FDG PET/CT, maximal standardized uptake values (SUVmax) were estimated. Immunohistochemical staining of tumor sections was performed for GLUT-1, GLUT-3, and HK-2, and for the cell proliferation maker Ki-67. Especially, by combining proportions and intensity of immunochemical staining, we evaluated modified immunohistologic scores of GLUT-1 and GLUT-3. RESULTS: The SUVmax of malignant melanoma lesions ranged from 2 to 18.7 (average; 9.1±5.4). Comparison between nodal and extranodal lesions revealed no significant difference of SUVmax (p=0.97). GLUT-1 staining showed the most positive expression level (89.5%, 17/19) among the diverse immunohistochemical markers. There were significant relationships between FDG uptake of malignant melanoma and GLUT-1 proportion (p<0.0001), GLUT-1 intensity (p<0.0001), GLUT-3 proportion (p=0.031), GLUT-3 intensity (p=0.009), GLUT-1 immunohistologic scores (p<0.0001), and GLUT-3 immunohistologic scores (p=0.028). HK-2 was not expressed in all melanoma samples. Although Ki-67 expression showed a high grade in all staining, there was no significant link between FDG uptake and Ki-67 grades (p=0.38). CONCLUSIONS: The data in this preliminary study indicate that FDG uptake in malignant melanoma is determined by GLUT-1 and GLUT-3, whereas HK-2 and Ki-67 play no role in FDG uptake of malignant melanoma.

Relationship Between Dual-Time Point FDG PET and Immunohistochemical Parameters in Preoperative Colorectal Cancer: Preliminary Study.

PURPOSE: The clinical availability of 2-deoxy-2-[18F] fluoro-D-glucose (FDG) dual-time point positron emission tomography/computerized tomography (DTPP) has been investigated in diverse oncologic fields. The aim of this preliminary study was to evaluate the relationship between various immunohistopathologic markers reflecting disease progression of colorectal cancer and parameters extracted from FDG DTPP in colorectal cancer patients. MATERIALS AND METHODS: Forty-seven patients with histologically confirmed colorectal cancer were analyzed in this preliminary study. FDG DTPP consisted of an early scan 1 h after FDG injection and a delayed scan 1.5 h after the early scan. Based on an analysis of FDG DTPP, we estimated the maximum standardized uptake value (SUV) of tumors on the early and delayed scans (SUVearly and SUVdelayed, respectively). The retention index (RI) was calculated as follows: (SUVdelayed - SUVearly) × 100/ SUVearly. The clinicopathological findings (size and T and N stages) and immunohistochemical factors [glucose transporter 1 (GLUT-1), hexokinase 2 (HK-2), p53, P504S, and ß-catenin] were analyzed by visual analysis. RESULTS: The RIs calculated from the SUVs ranged from -1.8 to 73.4 (31.8 ± 15.5). The RIs were significantly higher in patients with high T stages (T3 and T4) than with low T stages (T1 and T2; p < 0.05). Among the immunohistochemical analytic markers, GLUT-1 had the highest positive staining rate (93.6%) compared to other markers. Based on univariable analysis, it was shown that the RI of high-level GLUT-1 expression was significantly higher than low-level GLUT-1 expression (p = 0.01), and the RI of high-level p53 expression was slightly higher than low-level p53 expression (p = 0.08). Multivariate analysis to investigate a link between RI and clinicopathologic parameters of colorectal carcinoma showed that GLUT-1, p53, and T staging were independently connected with increased RIs (p < 0.05, total) using backward selection methods. There was no significant statistical relationship between SUVearly and SUVdelayed and clinicopathologic parameters in this study. CONCLUSION: The RIs obtained from preoperative colorectal cancers had a significant relationship to tumor size, T staging, GLUT-1, and p53, in contrast to SUVearly or SUVdelayed. Compared with previous reports, our results showed that RI can better predict GLUT-1 expression than HK-2 and other immunohistochemical markers. This study demonstrated that the RI might have the potential to be applied as a prognostic marker in preoperative colorectal cancer.

Post-traumatic Intramuscular Hemangioma of the Chest Wall.

Intramuscular hemangioma originated in chest wall is a rare benign tumor, with no relevant reports in Korea. In most cases, the tumor is discovered before the age of 30 years and it is reported that trauma operates as the initiation factor. It is essential to concern the clinical suspicion and conduct a CT scan for diagnosis. The principle of treatment is surgical excision with clear resection margin. The authors of this study report a case of surgical excision for post-traumatic intramuscular hemangioma of the chest wall with review of literature.

F-18 FDG PET/CT imaging of a Leydig cell tumor.

We report the F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of a patient with a testicular Leydig cell tumor. A 43-year-old man was referred for whole body FDG PET/CT imaging for health care screening. FDG PET/CT imaging demonstrated the presence of a focal hypermetabolic lesion in the right testicle and no specific findings in other areas. Based on the preoperative impression, right testis-sparing surgery was attempted. The tumor was pathologically confirmed as a Leydig cell tumor.

Struma ovarii and peritoneal strumosis with thyrotoxicosis.

BACKGROUND: Struma ovarii is a highly specialized form of mature ovarian teratoma consisting of thyroid tissue and exhibiting all the histological features of the thyroid gland. Malignant transformation of thyroid tissue in struma ovarii and metastasis are extremely uncommon. In rare cases, benign thyroid tissue may spread to the peritoneal cavity, and pathologic examination of the peritoneal implants shows multiple nodules of varying sizes of mature thyroid tissue similar to struma ovarii. This condition is termed "peritoneal strumosis." SUMMARY: We report a 49-year-old woman with struma ovarii complicated by peritoneal strumosis with thyrotoxicosis. After surgical resection of the struma ovarii and peritoneal strumosis the patient became euthyroid. CONCLUSION: To the best of our knowledge this is the first report of a patient with peritoneal strumosis complicated by thyrotoxicosis. The relative contribution to circulating thyroid hormones by the patient's struma ovarii as compared to the peritoneal strumosis is not known.

Alpha-methylacyl-CoA-racemase expression in adenocarcinoma, dysplasia and non-neoplastic epithelium of the stomach.

Alpha-methylacyl-CoA-racemase (AMACR) is an essential enzyme in the oxidation of bile acid intermediates and branched-chain fatty acids. This study aims to examine the expression pattern, as well as diagnostic and prognostic significance, of AMACR in carcinoma, dysplasia and non-neoplastic epithelium of the stomach. A total of 158 cases, including 66 cases of gastric carcinoma (GC), 48 cases of dysplasia and 44 cases of non-neoplastic gastric mucosa, were examined by immunohistochemistry for AMACR. AMACR expression was divided into two categories: negative (negative-weak staining intensity) and positive (moderate-strong staining intensity). AMACR immunoreactivity was detected in only 2 of 44 (4.5%) cases of non-neoplastic epithelium. A significantly high frequency of AMACR expression was found in 40 of 48 (83.3%) cases of dysplasia and 34 of 66 (51.5%) carcinoma cases compared with cases of non-neoplastic epithelium (p < 0.05). The frequency of AMACR expression was significantly higher in dysplasia than in carcinoma cases (p < 0.05). AMACR expression was higher in intestinal- than diffuse-type GC (p < 0.05). In conclusion, this study suggests that AMACR immunostaining aids in distinguishing malignant or precancerous lesions from reactive epithelial atypia in gastric biopsy specimens. It also suggests that AMACR expression is more likely to be associated with intestinal-type adenocarcinoma in gastric carcinogenesis.

Mucinous cystadenoma of the pancreas with predominant stroma creating a solid tumor.

BACKGROUND: Mucinous cystic neoplasm (MCN) of the pancreas is basically cystic epithelial neoplasm, unilocular or multilocular, occurring almost exclusively in women. CASE PRESENTATION: A 51-year-old female presented with a pancreatic mass incidentally found on the abdominal computed tomography. She underwent distal pancreatectomy. The sectioned surface of the pancreas revealed a circumscribed, whitish gray ovoid firm mass with some cystic spaces. Microscopically, glandular or small cystic structures were scattered in the predominant stroma creating a solid appearance. The subepithelial stromal component was composed of cytologically bland looking spindle cells, which resembled ovarian stroma. The stromal cells were reactive to CD 34, vimentin, progesterone receptor and calretinin. The microscopy was consistent with mucinous cystadenoma of the pancreas. CONCLUSION: This case of mucinous cystadenoma of the pancreas showed very interesting pathology: It was solid rather than cystic, and accompanied by abundant benign transitional epithelia, which was a very unusual and novel finding in the mucinous cystic neoplasm of the pancreas.

Gastric extremely well differentiated adenocarcinoma of gastric phenotype: as a gastric counterpart of adenoma malignum of the uterine cervix.

BACKGROUND: Most of gastric adenocarcinoma can be simply diagnosed by microscopic examination of biopsy specimen. Rarely the structural and cellular atypia of tumor cells is too insignificant to discriminate from benign foveolar epithelium. CASE PRESENTATION: A 67-year-old male presented with a gastric mass incidentally found on the abdominal computed tomography (CT) for routine medical examination. Gastric endoscopic examination revealed a huge fungating mass at the cardia and mucosal biopsy was performed. Microscopically the biopsy specimen showed proliferation of bland looking foveolar epithelia in the inflammatory background and diagnosed as foveolar epithelial hyperplasia. Because the clinical and endoscopic features of this patient were strongly suggestive of malignancy, the patient underwent radical total gastrectomy. The resected stomach revealed a huge fungating tumor at the cardia. The cut surface of the tumor was whitish gelatinous. Microscopically the tumor was sharply demarcated from surrounding mucosa and composed of very well formed glandular structures without significant cellular atypia, which invaded into the whole layer of the gastric wall. Tumor glands were occasionally complicated or dilated, and glandular lumina were filled with abundant mucin. Immunohistochemically the tumor cells revealed no overexpression of p53 protein but high Ki-67 labeling index. The tumor cells and intraluminal mucin were diffusely expressed MUC1 and MUC5AC and only focally expressed MUC2. On abdominal CT taken after 12 months demonstrated peritoneal carcinomatosis and multiple metastatic foci in the lung. CONCLUSION: The clinicopathologic profiles of gastric extremely well differentiated adenocarcinoma of gastric phenotype include cardiac location, fungating gross type, very similar histology to foveolar epithelial hyperplasia, foveolar mucin phenotype, lack of p53 overexpressoin and high proliferative index.

Solitary fibrous tumor arising in gastric serosa.

The solitary fibrous tumor (SFT) of peritoneum, especially arising in gastric serosa, is extremely rare. A case of SFT arising in gastric serosa of a 70-year-old man is reported. On abdominal computed tomography scan, an approximate 8.0 x 5.3 cm-sized solid mass with multiple nodular calcifications was noted in the omentomesentery of right upper abdomen, which was abutting to the gastric antral wall. At laparotomy the tumor was tightly attached to the gastric serosa and was completely excised by wedge resection of the stomach. The cut surfaces of the tumor were pale brown to pale yellow, firm, with multifocal yellowish, gritty, stony-hard nodules and cystic changes. Microscopically, the tumor was composed of mildly cellular benign-appearing spindle-shaped cells and bands of hyalinized collagen in varying proportions. The tumor revealed predominantly sclerosing pattern with extensive hyalinized fibrosis and multifocal dystrophic calcifications. The tumor was mainly located at the gastric serosa and subserosa, and its growth pattern was expansile with entrapping of muscularis propria and submucosa in the periphery of the tumor. By immunohistochemistry, the tumor cells were diffusely positive for CD34 and vimentin but negative for cytokeratin, desmin, smooth muscle actin, CD99 and c-kit. Although its occurrence is rare, SFT should be considered in the differential diagnosis of mesenchymal tumors of the stomach.