Makoto Urano

Primary primitive neuroectodermal tumor of the kidney

Primitive neuroectodermal tumor (PNET) is a small round cell sarcoma that mainly develops in the central nervous system and soft tissues of childhood; however recently, primary occurrence of this tumor in the kidney has been reported. We experienced one case of PNET primarily arose in the kidney without metastasis. The patient was a 28‐year‐old man whose chief complaint was abdominal pain, especially on exercise. On computed tomography scan and magnetic resonance imaging, a solid lesion was found in the left kidney, and a left nephrectomy was performed based on the diagnosis of a tumor in the left kidney. The tumor was within the parenchyma of lower end of left kidney protruding into the abdominal cavity. Histologically, diffuse proliferation of primitive small round cells with rosette formation was found. Immunohistochemically, MIC2 gene product, neuron‐specific enolase and S‐100 protein were positive. No metastasis to the regional lymph nodes was found. From these observations, the tumor was diagnosed as PNET primarily arising in the left kidney. Although chromosome analysis was not performed, EWS‐FLI1 chimera gene was identified by reverse transcriptase–polymerase chain reaction on the freshly frozen specimen and fluorescence in situ hybridization on paraffin sections.

Characterization of mammary analogue secretory carcinoma of the salivary gland: discrimination from its mimics by the presence of the ETV6-NTRK3 translocation and novel surrogate markers

Mammary analogue secretory carcinoma (MASC) is a recently recognized salivary gland tumor harboring an ETV6-NTRK3 translocation similar to secretory carcinoma of the breast. Histologically, MASC mimics papillary-cystic, microcystic, and follicular-type acinic cell carcinoma (AciCC) and low-grade cribriform cystadenocarcinoma (LGCCC) of the salivary gland. Using histology, immunohistochemistry (IHC), and molecular genetic techniques, we reevaluated 18 cases originally diagnosed as AciCC between 1993 and 2012. The last of these methods was used to detect the ETV6-NTRK3 translocation. The results reconfirmed 6 cases as AciCC (3 men; average age, 63 years) and helped us reclassify 10 cases as MASC (6 men; mean age, 46 years) and 2 as LGCCC (2 women; mean age, 48 years). Using IHC, we identified the 3 histologic types according to the expression patterns of vimentin, high-molecular-weight cytokeratin, cytokeratin 19, S-100, mammaglobin, MUC1, GATA-binding protein 3, adipophilin, α-amylase, DOG-1, SOX-10, and p63. The number of tumors diagnosed as MASC indicates that AciCC includes bona fide MASC cases. Because differential diagnosis among zymogen granule-poor AciCC, MASC, and LGCCC tumors is challenging, we recommend using molecular genetic tests for ETV6-NTRK3 for accurate diagnosis. Furthermore, detailed analyses of hematoxylin and eosin-stained tissues and IHC studies using the markers described here should be incorporated into routine practices.

Sclerosing mucoepidermoid carcinoma with eosinophilia of the salivary glands

We encountered two cases of low malignant mucoepidermoid carcinoma with scanty cellular atypism which originated in the parotid or submandibular gland and was characterized by marked fibrosis and eosinophilic infiltration within tumor tissue despite the predominance of the squamous component. Here we report these two cases and provide a review of the literature. We believe that clinically these two tumors with stromal fibrosis and eosinophilic infiltration have a low malignant potential, although histological examination revealed a scanty mucus-producing epithelial component. Therefore, we consider this type of tumor as a new subtype of mucoepidermoid carcinoma. A low-malignant mucoepidermoid carcinoma with stromal fibrosis and eosinophilic infiltration, as described in these two cases, may be misdiagnosed as a highly malignant mucoepidermoid carcinoma or squamous cell carcinoma because of its histologically scanty mucus-producing epithelial component. The objective of this study was to clarify their differences and to discuss the rendering of an accurate histological diagnosis, the degree of malignancy in relation to prognosis prediction, and the choice of therapy. In addition, we propose regarding this type of tumor as a new subtype of mucoepidermoid carcinoma.

Solitary squamous cell papilloma of the lung in a 40-year-old woman with recurrent laryngeal papillomatosis

A rare case of recurrent respiratory papillomatosis (RRP) is reported with a review of the literature. A 40‐year‐old Japanese woman had suffered from RRP since 1 year of age. She developed a pulmonary squamous papilloma with a thin‐walled cavity, which was suspected as being lung carcinoma. The trachea and bronchi around the tumor were intact, and no malignant transformation was present. Two types of human papillomavirus, 6 and 16, were detected, both in the laryngeal and pulmonary papillomas by in situ hybridization and the polymerase chain reaction method. To date, only 40 cases of juvenile laryngeal papilloma with pulmonary involvement have been reported in the English literature.

Cytological features of mammary analogue secretory carcinoma of salivary gland: Fine‐needle aspiration of seven cases

Mammary analogue secretory carcinoma (MASC) is a recently described salivary gland neoplasm that is defined by ETV6‐NTRK3 gene fusion. There have been few case reports on the cytopathologic features of MASC to date. We examined the clinicopathological and cytological features of seven cases of MASC defined by RT‐PCR analysis of the ETV6‐NTRK3 fusion gene. The cases occurred in three men and four women aged between 39 and 68 years, with a mean of 51.6 years. In five of these seven cases, the tumor involved the parotid gland. Histologically, all cases displayed predominantly microcystic patterns, often a mixture of follicular and papillary‐cystic structures. All tumors were immunoreactive for mammaglobin, S‐100 protein, and vimentin. Available fine‐needle aspiration cytology smears were cellular and exhibited many loosely cohesive syncytial clusters or isolated cells. Many histiocytes, some of which contained hemosiderin pigments, and variously shaped mucinous material were evident in the background or within the epithelial clusters. The majority of cases showed small to medium‐sized follicular structures with secreted materials. Papillary clusters were occasionally found. Tumor cells exhibited small to medium‐sized round to oval nuclei, with a smooth contour and indistinct or small nucleoli, and vacuolated cytoplasm. No tumor cells had obvious intracytoplasmic zymogen granules. It appeared that clusters of small to medium‐sized follicular and papillary configurations consisting of bland tumor cells with vacuolated cytoplasm, but lack of intracytoplasmic zymogen granules, in a mucinous or hemosiderin‐laden histiocyte‐rich background, were a characteristic cytological feature highly suggestive of MASC. Diagn. Cytopathol. 2014;42:846–855.

Warthin-like tumor variant of papillary thyroid carcinoma: Case report and literature review

A tumor approximately 4.0 × 3.0 cm in size with a cystic change was observed in the left lobe of the thyroid gland of a 52‐year‐old woman. The removed tumor had lymph follicle formation with a germinal center. This lymphatic tissue showed papillary and island‐like growth; the growths were surrounded by atypical epithelium showing nuclear features of papillary carcinoma. The atypical epithelium had ground‐glass nuclei with nuclear grooves, clearly indicating intranuclear cytoplasmic inclusion bodies. No chronic thyroiditis was observed in the background of the patient. Parts of the metastatic lymph nodes had cells with an eosinophilic cytoplasm, clearly showing an intratumor lymph follicle formation, as in the primary lesion. This is a rare case of thyroid papillary carcinoma similar to Warthins tumor of the salivary gland. Here we present this case, with a review of previously published reports.

Tall cell variant of papillary thyroid carcinoma: Its characteristic features demonstrated by fine‐needle aspiration cytology and immunohistochemical study

Tall cell variant (TCV) of papillary thyroid carcinoma is a rare tumor, which is usually associated with poor outcome, and pathologists often face the dilemma of proper diagnosis of TCV, not only by cytology but also histology. To allow surgeons to determine aggressiveness of the tumor before operation, it is important for pathologists to detect tall cell features correctly by fine‐needle aspiration cytology (FNAC). However, the current criteria and definition of TCV are still controversial and confounded by another problem, the differential diagnosis from poorly differentiated thyroid carcinoma (PDC).

Pancreatic ductal adenocarcinoma associated with Potter type III cystic disease.

Although polycystic liver disease (PLD) is known to be associated with autosomal dominant polycystic kidney disease, a finding of PLD with pancreatic ductal adenocarcinoma is extremely rare. We have experienced one such case of a ductal adenocarcinoma of the pancreas in a patient with Potter type III cystic disease of the liver and kidney. A 63-year-old man was admitted to our hospital because of obstructive jaundice. Six months previously, on admission to a local hospital for treatment of diabetes mellitus, he had been found to have polycystic disease of the liver and kidney. Ultrasound examination revealed dilatation of the intrahepatic bile duct and the common bile duct. Blood tests showed an elevated total bilirubin level. Abdominal computed tomography scans and magnetic resonance imaging demonstrated polycystic lesions in the liver and the bilateral kidneys. Percutaneous transhepatic cholangio-drainage was performed, and fluorography of the biliary tree revealed obstruction of the lower common bile duct, causing jaundice. This appears to be a case of independent association of pancreatic ductal adenocarcinoma with polycystic disease of the liver and kidney. The patients sister, who also had polycystic disease of the liver and kidney, had died of squamous cell carcinoma of the tongue. Although familial associations of carcinomas with polycystic liver disease may be extremely rare, they provide a perspective for the etiology of polycystic liver disease.

Analyses of proliferative potential in schwannomas

We report studies of schwannomas with a high percentage of MIB-1 positive cells. Thirty-eight specimens from 36 cases of schwannoma in the intracranial and spinal regions comprise the substance of this study. The MIB-1 positive cells were measured using immunohistochemical staining. In nine cases with a positivity index (PI) of 5% or more, immunohistochemical staining using DNA topoisomerase IIα (topo-II) and CD68 was performed. In some cases, we also searched for apoptosis with the TdT-mediated dUTP-biotin nick-end labeling (TUNEL) method. Three of nine cases with 5% or more positive MIB-1 cells had a very high cellularity with mitotic figures and were considered cellular Schwannomas. Their MIB-1 PI values were 8.21%, 10.00%, and 21.37%. However, the remaining six cases showed little evidence of malignancy. Their PIs were comparatively low, ranging from 5.19% to 8.41%, and the positive findings were localized in many cases. In these cases, we examined the sites where MIB-1 was measured and found that they corresponded to the borderline site between Antoni type A and B patterns and tended to be associated with an infiltration of CD68-positive macrophage. Furthermore, apoptotic cells appeared in the sites. With topo-II staining, the PIs in the same sites of these six cases were low, ranging from 0.78% to 1.93%. This implies that the high MIB-1 PI that was seen in these six cases was caused by reaction of MIB-1 to tumor cells that brought about an abnormality in the cell cycle by degeneration, such as apoptosis. In the site of formation of Antoni type B, MIB-1 may be a false positive in tumors with degenerative findings such as schwannomas. Topo-II was useful in these cases.

Local recurrence of sclerosing mucoepidermoid carcinoma with eosinophilia in the upper lip: a case report

IntroductionSclerosing mucoepidermoid carcinoma with eosinophilia is a rare morphological variant of thyroid carcinoma associated with Hashimoto’s disease. To date, only three such tumors have been reported in the minor salivary glands. We describe the first case, to the best of our knowledge, of recurrent sclerosing mucoepidermoid carcinoma with eosinophilia in the minor salivary glands of the upper lip.Case presentationA 61-year-old Japanese man was referred to our hospital with a mass in his median upper lip of four years’ duration. An examination of his median upper lip revealed a well-defined tumor measuring 9×12mm in diameter, which was subsequently resected. Three years after the first surgery, the tumor recurred and was resected. Both tumors were confirmed by histopathology to be sclerosing mucoepidermoid carcinoma with eosinophilia. Neither recurrence nor metastasis was observed in three and a half years of follow-up after the second surgery.ConclusionOur findings indicate that sclerosing mucoepidermoid carcinoma with eosinophilia can originate in the minor salivary glands and may be clinically or pathologically misdiagnosed as other conditions.