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91.

Background

Primary intestinal NK/T cell lymphoma is rare but aggressive and exhibits a poor prognosis. Little is known about its clinical characteristics because few studies with small sample sizes have been reported.

Aims

To provide clinicopathological features and endoscopic findings and to summarize the treatment outcomes of primary intestinal NK/T cell lymphoma to improve our understanding of this disease.

Methods

Between January 2011 to December 2016, 13 patients with confirmed primary gastrointestinal NK/T cell lymphoma at our center were described, and an updated literature review was provided.

Results

In this series of 13 cases, 69.23% were men, the median age was 39 years, and the median survival was 6 months. The common clinical manifestations included abdominal pain (76.92%) and gastrointestinal bleeding (46.15%). Lymphomas were common in the large intestine (69.23%). In 76.92% of patients, the clinical staging was stage I, and all 13 patients manifested ulcerative lesions and no tumor mass on endoscopy. The clinical characteristics of primary intestinal NK/T cell lymphomas were similar to results in existing literature.

Conclusion

Intestinal NK/T cell lymphoma shows nonspecific clinical features and poor prognosis, which is mainly expressed as ulcers on endoscopy. Emergency surgery may be an adverse prognostic factor of lymphoma, since it is prone to progress toward gastrointestinal perforation.  相似文献   
92.

Background

Low-grade malignant endolymphatic sac tumor (ELST) is a rare neoplasm, occurring in the inner ear and invading the temporal bone. This study aims to investigate the clinicopathological features of low-grade malignant ELSTs.

Methods

The clinicopathological data of 21 patients with low-grade malignant ELSTs were collected and analyzed.

Results

The patients were aged 16–71 years, with an average age of 40.3 years and a median age of 39 years, and the male to female ratio was 1:1.6. There were 13 cases (61.9%) of ELSTs occurring on the left side, 7 cases (33.3%) on the right side, and 1 case (4.8%) on both sides. Blood types O and B were noted in 71.4% of the patients. Immunohistochemistry showed that CK, EMA and Vim were all positive, and S-100 (71.4%, 10/14), CD56 (75.0%, 9/12), NSE (50.0%, 2/4), and GFAP (11.1%, 1/9) were also positive, while Syn, CgA, TTF-1, TG, CD34, and calcitonin were negative. The Ki-67 index was 4.3% on average. Histologically, cells were arranged in a papillary shape often with branches and abundant fibrous axial vessel. Some cells had an expanded different-sized thyroid-follicle-like structure, with the follicles containing red-stained colloids and scallop-like secretary vacuoles. There were expanded cavities. Some cases were in a glandular arrangement, and a few in a nest-like, gland-cystoid arrangement. Most tumors were coated with a monolayer of cubic epithelium, a few cells were flat or columnar, with translucent cytoplasm and light staining. The nuclei were oval, nucleolus was not obvious, chromatin was delicate, and a few nucleoli were small. The tissue was prone to bleeding, with fresh and old bleeding. Approximately half of the patients had necrotic bones, and in some cases the tumor tissue had destroyed the surrounding bone. The background fibrous tissue showed hyperplasia with hyaline degeneration, some had calcification and formation of sandy-gravel bodies. The clinical manifestations were hearing reduction or loss, followed by tinnitus, and accompanied by varying degrees of cranial nerve injury. No patients died during follow-up.

Conclusions

Low-grade malignant ELSTs occur most frequently on the left side, with a female preponderance. The disease progressed slowly, with no death, and but relapse in two patients in this series. These tumors are often misdiagnosed.  相似文献   
93.
It is accepted that alteration of connexin43 (Cx43) expression in glomeruli is a common pathological response in several forms of kidney diseases. To date, however the change of the Cx43 expression in obesity-related glomerulopathy (ORG) has not been reported. In this study, the alteration of Cx43 expression in the glomeruli of rat with ORG was defined. Five-week-old rats were fed with high-fat diet for 18 weeks to establish the ORG model, then the histological change of glomeruli, the foot process effacement of podocyte, the markers for podocyte injury (nephrin,podocin and WT1) and Cx43 expression in glomeruli were examined respectively. The results demonstrated metabolic disorder, hyperinsulinemia, systemic inflammation and microalbuminuria in ORG rats. There was significant hypertrophy, glomerular expansion and inflammatory cell infiltration in the kidney of ORG rats compared to the control group. Significant foot process effacement of the podocyte in the glomeruli, nephrin loss and density reduction were shown in the ORG rats, and Cx43 expression was significant upregulated in glomeruli of ORG rats compared to the control group. The results indicate the correlation of overexpressed Cx43 with the obesity related renal inflammation and suggest that Cx43 might be a potential target in the development of obesity related glomerulopathy.  相似文献   
94.
Association between HIV/AIDS and some of the cancers such as lymphomais is well known. Relative risk for developing non-Hodgkin lymphoma (NHL) increases 60–200 folds in HIV-infected individuals. Diffuse large B cell lymphoma (DLBCL), primary effusion lymphoma (PEL), Burkitt's lymphoma (BL) and Plasmablastic Lymphoma (PBL) are among the most frequent subtypes. During the last century, scientists found that the immune system could potentially detect and destroy cancer cells. Therefore, they started a new field of study, which is named immunotherapy. There are different immunotherapeutic methods, among which therapeutic antibodies, such as Brentuximabvedotin (Adcetris), Ibritumomabtiuxetan (Zevalin) and rituximab (Rituxan), used for treatment of NHLs showed promising results. In this article, we will review the immunotherapeutic option, monoclonal antibodies, for treatment of HIV-associated NHLs as well as their recent clinical status. We will also discuss the selective monoclonal antibody for each subtype of NHLs.  相似文献   
95.
The metastasis of neoplastic cells from their site of origin to distant anatomic locations continues to be the principal cause of death from malignant tumors, and that fact has been recognized by physicians for over a century. After the work done by Halsted in the treatment of breast cancer in the 1880s, accepted surgical canon held that metastasis occurred in a linear fashion, with centrifugal “growth in continuity” from the primary neoplasm that first involved regional lymph nodes. Those structures were considered to then be the sources of more distant, visceral metastases. With that premise in mind, radical and “ultra-radical” surgical procedures were devised to remove as many lymph nodes as possible in the treatment of carcinomas and melanomas. However, such interventions were ineffective in altering tumor-related mortality. This review considers the details of the historical material just mentioned. It also reviews currently-held concepts on biological mechanisms of metastasis, the “sentinel” lymph node biopsy technique, and the important topic of metastatic tumor “dormancy” as the cause of surgical treatment failure. Finally, predictive models of tumor behavior are discussed, which are based on gene signatures. These will likely be the key to identifying malignant lesions of low surgical stage that ultimately prove fatal through later manifestation of metastasis.  相似文献   
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98.
Laryngeal clefts are rare congenital malformations of the posterior laryngotracheal wall that lead to an abnormal communication between the airway and pharyngo-oesophageal tract. The condition is almost universally identified during infancy with minor laryngeal clefts very rarely diagnosed in adulthood. We present our tertiary centre’s experience of a large laryngeal cleft presenting at an advanced age, with the aim of increasing awareness of this correctible cause of respiratory distress and aspiration in adults.  相似文献   
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