Reflux gastritis: distinct histopathological entity?

A total of 98 patients who had either undergone gastric surgery (23) or who had peptic ulcers (56), or who had normal endoscopic findings (19), all underwent gastric biopsy, together with measurement of pH and total bile acid concentration in their fasting gastric juice. The biopsy specimens were graded "blind" for the presence of foveolar hyperplasia; oedema and smooth muscle fibres in the lamina propria; vasodilation and congestion of superficial mucosal capillaries; and a paucity of both acute and chronic inflammatory cells in the brief that these features constituted a distinctive histological picture related to reflux of alkaline duodenal content into the stomach. We found a strong association between severe grades of each of these histological variables and both hypochlorhydria (pH greater than or equal to 4) and increased bile acid concentrations in the stomach. Furthermore, when the individual grades were added together to give a composite "reflux score," there was a significant difference in the incidence of hypochlorhydria (p less than 0.01) and raised bile acid concentrations (p less than 0.005) between those patients with a reflux score above and below 10. Although we do not claim that reflux is invariably accompanied by a distinctive histological picture, we suggest that recognition of this hitherto poorly documented combination of features as reflux gastritis may assist in the selection of patients for specific treatment and minimise the overdiagnosis of premalignant dysplasia (with which the lesion may be confused) in the postoperative stomach.     

Renal angiomyoadenomatous tumor: morphologic, immunohistochemical, and molecular genetic study of a distinct entity

We present a series of a distinct tumorous entity named renal angiomyoadenomatous tumor (RAT). Five cases were retrieved from the consultation files of the authors. Histologic and immunohistochemical features were evaluated. Sequencing analysis of coding region of the VHL gene was carried out in all cases. The tumors were composed of admixture of an epithelial clear cell component and prominent leiomyomatous stroma. Epithelial cells formed adenomatous tubular formations endowed with blister-like apical snouts. All tubular/glandular structures were lined by a fine capillary network. The epithelial component was positive for epithelial membrane antigen, CK7, CK20, AE1-AE3, CAM5.2, and vimentin in all cases. In all analyzed samples, no mutation of the VHL gene was found. RAT is a distinct morphologic entity, being different morphologically, immunohistochemically, and genetically from all renal tumors including conventional clear cell carcinoma and mixed epithelial and stromal tumor of kidney.     

Spondylo-camptodactyly syndrome: a distinct autosomal dominant entity?

We present a family in which five members over three generations have a syndrome characterized by camptodactyly, flattened bodies of cervical vertebrae, and a variable degree of thoracic scoliosis. After excluding other camptodactyly syndromes, it was concluded that this association of anomalies probably represents a new autosomal dominant syndrome.     

MICRO syndrome: an entity distinct from COFS syndrome

Children born with the findings of microcephaly, cataracts and microcornea can result not only from a prenatal viral infection, but also from an autosomal recessive Mendelian disorders. We present three pairs of affected siblings with MICRO syndrome, who were born with congenital microcephaly, microcornea, and cataracts. MICRO syndrome is an autosomal recessive syndrome consisting of congenital microcephaly, cortical dysplasia, microcornea, cataracts, optic atrophy, severe mental retardation, hypotonic diplegia, and hypogenitalism. At birth, MICRO syndrome resembles Cerebro-Oculo-Facio-Skeletal (COFS) syndrome, but it differs in the lack of the rapidly progressive neurologic features leading to severe brain atrophy with calcifications. Patients with MICRO syndrome manifest frontal cortical dysplasia, hypoplasia of the corpus callosum, cortical blindness with optic atrophy, profound mental retardation, and progressive joint contractures with growth failure. COFS syndrome shares also many clinical and cellular similarities with Cockayne syndrome (CS), and cultured cells in both conditions demonstrate hypersensitivity to ultraviolet (UV) radiation due to impaired nucleotide excision repair (NER). NER studies in cultured fibroblasts from MICRO patients give normal results, so MICRO syndrome should be considered in children with features resembling COFS syndrome and CS, but who have normal NER. MICRO should be distinguished from other similar clinical disorders with normal NER by the presence of significant visual impairment and cortical blindness despite early surgery for congenital cataracts, frontal polymicrogyria, thin corpus callosum, and cortical atrophy by MRI.     

Nasal polyposis in a chimpanzee

A 15-year-old female chimpanzee with nasal polyposis sustained respiratory compromise when she was sedated and expired despite resuscitative efforts. Postmortem examination revealed very large fibromyxomatous nasal polyps completely obstructing the upper airway. Gross examination and histopathologic findings were indistinguishable from those of human polyps. The chimpanzee is a potential animal model for nasal polyposis that could provide basic information concerning the relationship of polyps to type I hypersensitivity and to three severe respiratory tract disorders in humans: cystic fibrosis, bronchial asthma, and the immotile cilia syndrome.     

Peutz-Jeghers syndrome: a new understanding

Peutz-Jeghers syndrome is an autosomal dominant inherited disorder characterized by hamartomatous polyps in the small bowel and mucocutaneous pigmentation. Patients with Peutz-Jeghers syndrome often present as surgical emergencies with complications of the polyps, such as intussusception, bowel obstruction and bleeding. Furthermore, repeated operations may be needed in some patients, which may result in short bowel syndrome. Although early reports did not demonstrate a predisposition to cancer in patients with this syndrome, more recent studies have described an increased risk for both gastrointestinal and extra-gastrointestinal cancers. Women with the Peutz-Jeghers syndrome have the extremely high risk for breast and gynecologic cancer. Recently, Peutz-Jeghers syndrome susceptibility gene, encoding the serine threonine kinase STK11 (also called LKB1), was identified in families with Peutz-Jeghers syndrome. The identifications of germline mutations in families with Peutz-Jeghers syndrome could be a turning point in the management of Peutz-Jeghers syndrome.     

Cellular schwannoma: a distinct pseudosarcomatous entity

Eighteen cases of cellular schwannoma, a recently delineated benign entity, are described. These tumours present most often in middle-aged adults of either sex and show a predilection for the paravertebral region of the mediastinum and retroperitoneum. More than half the tumours macroscopically arose from a nerve but none was associated with von Recklinghausen's disease. The light microscopic features are remarkably consistent but are not immediately recognizable as neural in type. Means of distinction from a malignant nerve sheath tumour and from a variety of other soft tissue tumours are discussed. Immunohistochemical positivity for S-100 protein has been demonstrated in 17 of the 18 cases. Prolonged follow-up has revealed local recurrence in only one case; none has metastasized.     

Molecular classification and genetic pathways in hyperplastic polyposis syndrome

Hyperplastic Polyposis (HPPS) is a poorly characterized syndrome that increases colorectal cancer (CRC) risk. We aimed to provide a molecular classification of HPPS. We obtained 282 tumours from 32 putative HPPS patients with >or= 10 hyperplastic polyps (HPs); some patients also had adenomas and CRCs. We found no good evidence of microsatellite instability (MSI) in our samples. The epithelium of HPs was monoclonal. Somatic BRAF mutations occurred in two-thirds of our patients' HPs, and KRAS2 mutations in 10%; both mutations were more common in younger cases. The respective mutation frequencies in a set of 'sporadic' HPs were 18% and 10%. Importantly, the putative HPPS patients generally fell into two readily defined groups, one set whose polyps had BRAF mutations, and another set whose polyps had KRAS2 mutations. The most plausible explanation for this observation is that there exist different forms of inherited predisposition to HPPS, and that these determine whether polyps follow a BRAF or KRAS2 pathway. Most adenomas and CRCs from our putative HPPS patients had 'classical' morphology and few of these lesions had BRAF or KRAS2 mutations. These findings suggest that tumourigenesis in HPPS does not necessarily follow the 'serrated' pathway. Although current definitions of HPPS are sub-optimal, we suggest that diagnosis could benefit from molecular analysis. Specifically, testing BRAF and KRAS2 mutations, and perhaps MSI, in multiple polyps could help to distinguish HPPS from sporadic HPs. We propose a specific model which would have diagnosed five more of our cases as HPPS compared with the WHO clinical criteria.     

Nephrotic syndrome with mesangial-cell proliferation in children--a distinct entity?

Various morphologic patterns have been identified in renal biopsies of children with the idiopathic nephrotic syndrome. Children with focal segmental glomerulosclerosis have clinicopathologic features sufficiently distinct to warrant a separate subclassification. "Immunoglobulin M (IgM) nephropathy" and other morphologic patterns are less well defined. The clinicopathologic characteristics of eight patients with the nephrotic syndrome, increased mesangial cellularity on renal biopsy, and hematuria (mesangioproliferative nephropathy) were evaluated. Response to standardized prednisone therapy was poor. Of the seven children followed for 7-29 months, only two were in remission at the time of writing, and each of these had had one prior relapse. The eighth patient was lost to follow-up after one month. Although the number of patients studied was small, there was a strong correlation between degree of mesangial-cell proliferation and failure of primary treatment. As concepts of the pathogenesis of idiopathic nephrotic syndrome in children continue to evolve, the mesangioproliferative lesion should be recognized and marked for further study.     

Primary thyroid thymoma: a distinct clinicopathologic entity

A 51-year-old man presented with a paratracheal tumor. He had undergone resection of a thyroid tumor 15 years previously; at that time, the histologic diagnosis had been anaplastic carcinoma. When the tumor recurred, the presumptive clinical diagnosis was medullary thyroid carcinoma. Histologic examination revealed a poorly differentiated epithelial tumor with immunoreactivity for keratins, carcinoembryonic antigen, and, focally, S-100 protein. The tumor was negative for calcitonin and thyroglobulin. There were scattered lymphocytes and plasma cells. Ultrastructural examination showed elongated epithelial cells with prominent desmosomes and bundles of cytoplasmic tonofilaments but no secretory granules; amyloid was not present ultrastructurally or histochemically. The characteristic ultrastructural and immunocytochemical features and the clinical behavior of this tumor verify the existence of primary thyroid thymoma. This new primary thyroid neoplasm is of clinical importance, considering the more benign behavior of primary thyroid thymoma than of other tumors in the differential diagnosis of this lesion.     

Nasal polyposis and fungal Schizophyllum commune infection: a case report

We present a rare case of eosinophilic fungal rhinosinusitis with nasal polyps in a 32-year-old woman caused by basidiomycete fungus Schizophyllum commune. Diagnosis was done by the endoscopic nasal examination, computed tomography (CT) of the paranasal sinuses, the histopathological examination of polyps, the presence of eosinophils and fungal hyphae in nasal mucus and by the detection of S. commune by culture. The patient was successfully treated by combination of oral itraconazole and topical corticosteroid therapy combined with surgery. The pathogenesis and diagnosis of allergic fungal rhinosinusitis are also discussed.