Masayoshi Fujisawa

Aberrant expression of an “intestinal marker” Cdx2 in pyloric gland adenoma of the gallbladder

The aim of this study was to survey Cdx2 expression in pyloric gland adenoma (PGA) of the gallbladder. We reviewed 29 PGA cases, ten (34.4%) and seven (24.1%) of which showed intestinal metaplasia (IM) and squamous morule (SM), respectively. The immunostaining for Cdx2, beta-catenin, MUC5AC, MUC2, MUC6, and M-GGMC-1 was performed and scored (0 = negative, 1+ = <10%, 2+ = 10% to <30%, 3+ = 30% to <50%, 4+ = 50% to <70%, 5+ = 70–100%). Although its scores were relatively low (1+ or 2+), Cdx2 was frequently expressed in 27 cases (93.1%). Not only goblet and/or Paneth cells were positive but also non-IM cells in PGAs, as opposed to the lack of staining in the background mucosa. Cdx2 scores were not correlated with those of IM (p = 0.485) and MUC2 (p = 0.868). Of note, Cdx2 was positive in foci of SM in all seven cases, and there was a significant difference in Cdx2 scores between PGAs with and without SM. Furthermore, the p value of scores between Cdx2 and beta-catenin was 0.051, and both mean labeling indices (LIs) were correlated (r = 0.736). With Cdx2, higher morular LIs than glandular LIs were observed (p = 0.001). Finally, we concluded that aberrant Cdx2 expression in PGAs is closely associated with nuclear beta-catenin expression and SM in contrast with IM.

Oxaliplatin-induced Liver Injury Mimicking Metastatic Tumor on Images: A Case Report

Oxaliplatin-based chemotherapy is widely used for advanced colorectal cancer treatment, but it occasionally induces liver injury that is characterized histologically by sinusoidal dilatation, hepatic plate atrophy and/or venular obstruction. Most of the patients do not reveal apparent radiological abnormalities, however. Here, we report the case of a 47-year-old man with a radiologically detectable mass-forming oxaliplatin-induced sinusoidal injury that mimicked multiple liver tumors. These mass lesions were found on computed tomography images after the administration of six cycles of folinic acid, fluorouracil and oxaliplatin therapy as adjuvant chemotherapy for Stage III rectal cancer. The patient had to undergo liver resection because imaging studies could not exclude metastases. The histological examination revealed that a resected mass lesion was composed of severe sinusoidal dilatation. Milder dilatation was also seen in the surrounding parenchyma. We diagnosed the patient as having an oxaliplatin-induced sinusoidal injury with severe deviation. As oxaliplatin is a standard agent in colorectal cancer therapy today, all clinicians and pathologists should be aware of such non-neoplastic lesions as one of the rare differential diagnoses of metastatic liver tumor, to prevent overtreatment.

Nonfunctioning endocrine pancreatic tumor examined with 18F-FDG PET/CT

A 71-year-old woman with type 2 diabetes mellitus complained of generalized fatigue. A 36-mm tumor in the pancreatic tail was detected with ultrasonography. The tumor was found to have marked hypervascularity with contrast-enhanced computed tomography (CT) and magnetic resonance. Combined 18F-fluorodeoxyglucose positron emission tomography and CT (18F-FDG PET/CT) showed 18F-FDG by the tumor with a maximal standardized uptake value of 2.98 at 50 min and 3.29 at 100 min following injection of 18F-FDG. 18F-FDG PET/CT suggested no extrapancreatic spread of the tumor. The patient had no pancreatic hormone-associated symptoms. Distal pancreatectomy was performed, and a well-differentiated endocrine tumor was diagnosed. The resected specimen showed neither infiltration of adjacent structures nor metastasis to regional lymph nodes. The present case suggests that 18F-FDG PET/CT is a reliable modality for staging endocrine pancreatic tumors.

Factors that make it difficult to diagnose cervical tuberculous lymphadenitis

Cervical tuberculous lymphadenitis is mainly diagnosed by analyzing tissue samples obtained by fine-needle aspiration (FNA). However, some cases remain diagnostic challenges even after polymerase chain reaction analysis of FNA specimens. To delineate differences between cases that are relatively easy to diagnose and those for which diagnosis is difficult, 22 patients with cervical tuberculous lymphadenitis were studied retrospectively. FNA tissues were used to diagnose 14 cases (group A), whereas excisional biopsy was required for accurate diagnosis of 8 cases (group B). These two groups were compared with regard to results of blood examinations, ultrasound appearance, and various other procedures required to reach the final diagnosis. The results indicated that diagnosis of cervical tuberculous lymphadenitis was more difficult for patients with lower white blood cell counts, lower serum C-reactive protein levels, and absence of lymph node fusion or abscess formation on ultrasonography. The possibility of tuberculosis as a cause of cervical lymphadenopathy should always be considered, even when the presenting symptoms are not typical of this disease.

A Novel Role of Spred2 in the Colonic Epithelial Cell Homeostasis and Inflammation

Rapid and adequate mucosal healing is important for a remission of ulcerative colitis (UC) patients. Here, we examined whether Spred2, a member of the Sprouty-related EVH1-domain-containing proteins that inhibit the Ras/Raf/ERK pathway, plays a role in colonic mucosal homeostasis and inflammation by using Spred2 knockout (KO) mice. We first detected increased epithelial cell proliferation and cadherin 1 expression in the colon of naïve Spred2 KO mice compared to wild-type mice. Interestingly, Spred2 KO mice were resistant to dextran sulfate sodium (DSS)-induced acute colitis as indicated by lower levels of body weight loss and disease activity index. Histologically, epithelial cell injury and inflammation were milder in the colonic mucosa of Spred2 KO mice on day 3 and almost undetectable by day 8. Experiments with bone chimeric mice indicated that Spred2-deficiency in non-hematopoietic cells was responsible for the reduced sensitivity to DSS. Finally, Spred2 KO mice developed significantly fewer tumors in response to azoxymethane plus DSS. Taken together, our results demonstrate, for the first time, that Spred2 plays an important role in the regulation of colonic epithelial cell proliferation and inflammation by potentially down-regulating the activation of ERK. Thus, Spred2 may be a new therapeutic target for the treatment of UC.

Autoimmune Pancreatitis: Pancreatic Manifestation of Igg4-related Disease

Abstract Autoimmune pancreatitis (AIP) is a unique inflammatory disorder of the pancreas. Two histological types are recognized: lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric chronic pancreatitis, with the former representing the pancreatic manifestation of IgG4-related disease. Presented here is a 64-year-old man who was incidentally found to have a mass in the pancreatic tail. The resected specimen revealed typical histological features of lymphoplasmacytic sclerosing pancreatitis, consisting of storiform fibrosis, obliterative phlebitis, and characteristic lobular and ductal inflammation. IgG4-positive plasma cells were numerous, and his serum IgG4 level was elevated (436 mg/dL). He also had systemic lesions, such as hypophysitis, bilateral eyelid lesions and bilateral pleural thickening, that most likely represented IgG4-related disease. Sometimes the distinction of AIP from cancer is clinically difficult, especially in cases with a localized lesion and/or without serological abnormalities; thus, pancreatic resection may be carried out. Pancreas biopsy is attracting attention as a diagnostic tool, and pathologists may play an important role in diagnosing AIP in the future.

Spred2 Deficiency Exacerbates D-Galactosamine/Lipopolysaccharide -induced Acute Liver Injury in Mice via Increased Production of TNFα

Acute liver injury (ALI) is characterized by hepatocyte damage and inflammation. In the present study, we examined whether the absence of Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK pathway, influences ALI induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS). Compared to wild-type mice, Spred2−/− mice developed exacerbated liver injury represented by enhanced hepatocyte damage and inflammation. Enhanced ERK activation was observed in Spred2−/−-livers, and the MEK/ERK inhibitor U0126 ameliorated ALI. Hepatic tumour necrosis factor α (TNFα) and interleukin (IL)-1β levels were increased in Spred-2−/−-livers, and the neutralization of TNFα dramatically ameliorated ALI, which was associated with decreased levels of endogenous TNFα and IL-1β. When mice were challenged with D-GalN and TNFα, much severer ALI was observed in Spred2−/− mice with significant increases in endogenous TNFα and IL-1β in the livers. Immunohistochemically, Kupffer cells were found to produce TNFα, and isolated Kupffer cells from Spred2−/− mice produced significantly higher levels of TNFα than those from wild-type mice after LPS stimulation, which was significantly decreased by U0126. These results suggest that Spred2 negatively regulates D-GalN/LPS-induced ALI under the control of TNFα in Kupffer cells. Spred2 may present a therapeutic target for the treatment of ALI.

Ovarian stromal cells as a source of cancer-associated fibroblasts in human epithelial ovarian cancer: A histopathological study

Fibroblasts are a major component of cancer tissue and known to contribute to cancer progression. However, it remains unknown whether they are derived from local fibroblasts or of other origin. This study was designed to identify the contribution of local stromal cells to cancer stroma in human epithelial ovarian cancer. Seventy-six cases of surgically resected primary ovarian carcinoma (48 cases confined to the ovaries and 28 cases with distant metastases) and 17 cases of secondary ovarian tumor (e.g. colon cancer metastasized to the ovary) were enrolled in this study. The tissues were immunostained for forkhead box protein L2 (FOXL2), a transcription factor crucial for ovarian development and function, and markers for cancer-associated fibroblasts (CAFs) and inflammatory cells. Under normal condition, FOXL2 expression was restricted to ovarian stromal cells and some other types of cells in female genital tracts and never found in other sites of the body. FOXL2-positive cells were found in all primary and secondary tumors in the ovary, and were the dominant stromal cells in most cases. In contrast, only a few FOXL2-positive cells were found in peritoneal seeding sites of four serous carcinoma cases, and all the other tumors at extraovarian sites had no FOXL2-positive cells. FOXL2-positive cells in the ovarian lesion variably expressed CAFs markers, such as alpha-smooth muscle actin and fibroblast activating protein, as determined by double immunostaining. Background inflammation, but not histological subtype or origin of the neoplasm seemed to correlate with the proportion of FOXL2-positive cells. These results suggest that ovarian stromal cells are the main source of cancer stroma in the ovary but do not seem to move to distant sites via circulation together with tumor cells. Our results also support the hypothesis that cancer-associated fibroblasts may originate locally, which was previously demonstrated using animal models.

Molecular Subtypes of Breast Cancers from Myanmar Women: A Study of 91 Cases at Two Pathology Centers

Background: Breast cancer is the most common cancer in Myanmar women. Revealing the hormonal receptor status, human epidermal growth factor receptor 2 (HER2) and Ki-67 expression is useful for estimating patient prognosis as well as determination of treatment strategy. However, immunohistochemical features and classification of molecular subtypes in breast cancers from Myanmar remain unknown. Methods: The clinicopathological features of 91 breast cancers from Myanmar women were examined. Immunohistochemistry was performed on tissue specimens with antibodies to estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki-67, cytokeratin (CK)5/6 and CK14. Immunohistochemistry-based molecular subtyping was conducted. Results: Breast cancers in Myanmar women were relatively large, high grade with frequent metastatic lymph nodes. Of the 91 patients, tumors with ER positive, PgR positive, and HER2 positive were 57.1%, 37.4%, and 28.6%, respectively. The most prevalent subtype was luminal B (HER2-) (39.6%), followed by HER2 (22.0%), triple negative (TN)-basal-like (12.1%), luminal A (11.0%), TN-null (8.8%) and luminal B (HER2+) (6.6%). The mean Ki-67 expression of 91 cases was 33.9% (33.9% ± 19.2%) and the median was 28% (range; 4%-90%). The mean Ki-67 expression of luminal A, luminal B, HER2 and TN-basal-like/null was 7%, 30%, 40%, and 57%/43%, respectively. A higher Ki-67 expression significantly correlated with a higher grade, larger size and higher stage of malignancy. Conclusions: We, for the first time, investigated the histopathological features of breast cancers from Myanmar women. Myanmar breast cancers appeared to be aggressive in nature, as evidenced by high frequency of poor-prognosis subtypes with high level of Ki-67 expression.

Mucocele in the middle ear

A 44-year-old Japanese man initially presented with vertigo during body movement. The patient did not complain of any ear symptoms. He had been receiving regular treatment for bronchial asthma and also displayed chronic pansinusitis without nasal polyposis that had not been treated. He had experienced right acute otitis media 3 years earlier but had not undergone myringotomy. Clinical examination revealed a yellowish-white cystic mass in the posterosuperior quadrant of the right tympanic membrane (Fig. 1A). Audiometry demonstrated normal hearing on both sides. The condition of the patient had already improved by the time examinations were performed, and no nystagmus was observed, irrespective of head position. Benign paroxysmal positional vertigo was suspected. Computed tomography targeting the ear revealed a soft tissue mass at the mesotympanum of the right middle ear (Fig. 2, A and B). Magnetic resonance imaging showed the lesion as an isointense to slightly hyperintense region on both T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) (Fig. 2, C and D). However, the mass lesion was too small to be detected on diffusion-weighted imaging. Cholesteatoma or cyst was suspected, and extirpation of the mass lesion was performed using a transmeatal approach. A lump of connective tissue was found occupying the right posterior middle ear cleft, adherent to the tympanic membrane and chorda tympani. The round, yellow mass (5 3mm) was completely resected while preserving the chorda tympani. The lesion displayed a smooth surface lined by epithelium (Fig. 1B). Histologically, situated beneath the epithelium was a pool of mucus including foamy macrophages, eosinophils, and plasma cells in the superficial lamina propria, with dilatation of the accessory gland surrounded by inflamed fibrous tissue (Fig. 1C). The final diagnosis was mucocele of the middle ear. In the head and neck region, most mucoceles have been reported in the paranasal sinus or mouth. Although chronic rhinosinusitis and allergic disease are the most common causes of mucocele formation and chronic inflammation frequently occurs in the middle ear, middle ear mucocele is either extremely rare or such mucoceles in the middle ear remain unnoticed because they may seldom cause symptoms, as seen in the present case. Farris et al. (1) reported a case of middle ear mucocele as an unusual complication of surgery for acoustic neuroma. In that case, surgical closure of the Eustachian tube was suggested as a potential cause of mucocele formation in the middle ear. Early in the disease process, the large amount of water contained by the mucocele results in a lower signal intensity on T1WI and higher signal intensity on T2WI. As the mucocele becomes chronic, decreasing amounts of water result in an increased proportion of protein and, thus, progression toward signal hyperintensity on T1WI and decreased signal intensity on T2WI (2). Mucocele can thus display various signal intensities on MRI, making preoperative diagnosis difficult. Histopathologically, the most frequent finding in mucocele is the presence of a predominantly mononuclear inflammatory process in the subepithelial connective tissue, mainly involving mature lymphocytes and plasma cells (3). In the present case, in addition to the aforementioned elements, infiltration of eosinophils was observed. Eosinophilic otitis media is an intractable otitis media characterized by eosinophilic infiltration and highly viscous mucoid effusion and is found in patients with adult-onset asthma (4). Although the conditions in this case were far from the diagnostic criteria for eosinophilic otitis media (4), the treatments being taken for asthma might have helped mask the disease. We considered that this mucocele was caused by poor drainage and compromised ventilation of the middle ear because of poor function of the Eustachian tube. Because paranasal sinus mucoceles can cause various ophthalmologic manifestations including optic neuropathy (5), expansive mucocele of the middle ear also may potentially result in Address correspondence and reprint requests to Tomoyasu Tachibana, M.D., Department of Otolaryngology, Himeji Red Cross Hospital, 12-1 Shimoteno 1-Chome, Himeji City, Hyogo 670-8540, Japan; E-mail: tomoyasutachibana@hotmail.co.jp The authors disclose no conflicts of interest. Otology & Neurotology 35:e92Ye94 2014, Otology & Neurotology, Inc.