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1.
Primary salivary gland carcinoma with neuroendocrine differentiation is of rare occurrence, especially so in the parotid gland. Amongst the various reported primary tumors with neuroendocrine differentiation, acinic cell carcinoma (ACC) one such tumor. A 48 year old lady presented with a gradually increasing right infra-auricular swelling for a period of 1 year which enlarged suddenly in a short period. Contrast Enhanced Computed Tomography (CECT) suggested diagnosis of Pleomorphic Adenoma. Fine Needle Aspiration Cytology (FANC) yielded a cystic fluid suggesting a possibility of Warthin’s tumor or Oncocytic lesion. Intraoperative findings were suggestive of a Warthin’s tumor. Initial histopathological examination of the tumor was suggestive of neuroendocrine carcinoma. However, extensive sectioning revealed peripheral islands of ACC. Immunoexpression of S-100, Neuron specific Enolase (NSE), Chromogranin A and Synaptophysin confirmed the diagnosis. The possibility of neuroendocrine differentiation in a primary salivary gland tumor should be kept in mind whenever a salivary gland tumor shows only neuroendocrine histology.  相似文献   
2.
Abstract: We performed a retrospective analysis of clinical course of 91 patients who developed both breast cancer and a chronic lymphoproliferative neoplasm and were seen at the M. D. Anderson Cancer Center between January 1, 1970 and December 30, 1991. The sample included 24 individuals who developed lymphoproliferative neoplasm first (Group A), 22 individuals with concurrent diagnosis of both malignancies (Group B), and 45 individuals who developed breast cancer first (Group C). The median time to diagnosis of secondary breast cancer and lymphoproliferative neoplasm was 66 months (range, 7–459) and 65 months (range, 0–334), respectively. A higher proportion of Group B lymphomas were low-grade (77% vs. 47% [Group A] vs. 37% [Group C] p = 0.009). Prior occurrence of either one of these malignancies did not affect the disease-specific survival from the second malignancy. However, continuing mortality from the first malignancy appeared to contribute to a poor overall survival following second malignancy. Group A included 8 patients who developed breast cancer following radiation therapy for Hodgkin's disease after a mean interval of 18 (± 4.3) years. Three of these individuals had coexisting ductal and lobular histology (vs. none of the individuals in Groups B and C, p = 0.02). Another interesting finding was the high incidence of multiple additional malignancies in this patient population. A total of 29 additional neoplasms occurred in 21 (23%) of the 91 study subjects. These malignancies involved a wide variety of organ sites and could not be attributed to the therapy for either the breast cancer or the lymphoma in most cases. The data suggest that individuals who develop both breast cancer and a lymphoproliferative neoplasm are at a high risk for multiple malignancies. Close surveillance of such individuals for additional malignancies and further studies to understand the molecular basis of this predisposition are warranted.?  相似文献   
3.
Optimal care of patients with locally advanced breast cancer requires the use and thoughtful integration of all effective modalities of treatment. A number of alternative combinations of surgery, chemotherapy, and radiation have been promoted, each with its own particular advantages and shortcomings. The advantages of sequenced, multimodality therapy of locally advanced, noninflammatory breast cancer include (1) the ability to convert nonresectable tumors to resectable ones, (2) early institution of systemic therapy, (3) in vivo evaluation of tumor response with the potential for optimization of therapy, and (4) relatively low morbidity rates with the ability to render most patients disease-free at their primary site. The results of this treatment strategy are discussed.  相似文献   
4.
Correlation of p53 gene/protein alterations with incidence of oncogene amplification, a potential marker of prognosis, was evaluated in 26 fresh breast cancer samples. p53 gene was analyzed by SSCP and DNA sequencing while p53 protein status was investigated by immunohistochemistry (IH). Amplification of c-erbB2/neu, c-myc, N-ras, int-2, hst, PRAD-1 and EGFR genes was studied by slot blot and in situ hybridizations. p53 alterations were found in 31% cases by SSCP and 42% by IH; gene amplification was detected in 27% cases. p53 gene alterations correlated significantly with gene amplification (p=0.006) and also with higher S-phase index (p=0.026), aneuploidy (p=0.026) and negative progesterone receptor status (p=0.043).  相似文献   
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The present study was taken up to investigate the effect of petroleum ether extract of Tinospora cordifolia (Wild.) Miers, on depression in mice. The extract (50, 100 and 200 mg/kg, p.o.) was administered for 14 successive days to Swiss young albino mice (either sex) and evaluated for antidepressant-like activity using tail suspension test and forced swim test. Petroleum ether extract at all three doses produced significant antidepressant-like effect in tail suspension test as well as in forced swim test and their efficacies were found to be comparable to imipramine (15 mg/kg, p.o.) and sertraline (20 mg/kg, p.o.). The extract at a dose of 50 mg/kg showed most potent effect and did not show any significant change in locomotor functions of mice as compared to control. The antidepressant-like effect of the extract was significantly reversed by pretreatment of animals with prazosin (a α(1)-adrenoceptor antagonist), sulpiride (a selective dopamine D(2)-receptor antagonist), p-CPA (a serotonin synthesis inhibitor) and baclofen (GABA-B agonist), when tested in tail suspension test. Moreover, petroleum ether extract also reduced the mouse whole brain monoamine oxidase (MAO-A and MAO-B) activities as compared to control, resulting in increase in the levels of brain monoamines. Therefore, the extract may have potential therapeutic value for the management of depressive disorders.  相似文献   
7.
A 65-year-old patient with endometrial adenocarcinoma underwent hysterectomy. Pathological examination of the right ovary revealed a coexisting stromal luteoma. The possible relationship between the two neoplasms as well as the intriguing pathogenesis and controversial nomenclature of ovarian steroid cell tumors are discussed. The incidental discovery of a stromal luteoma in a total hysterectomy specimen removed for endometrial carcinoma raises interesting questions about the perceived innocuous nature of these rare lipid cell tumors.  相似文献   
8.
Here we describe the design and synthesis of pyrazolo[3,4-d]pyridazines as adenosine receptor (AR) ligands. We demonstrate that the introduction of a 3-phenyl group, together with a 7-benzylamino and 1-methyl group at the pyrazolopyridazine scaffold, generated the antagonist compound 10b, which displayed 21 nM affinity and a residence time of ∼60 min, for the human A1R, 55 nM affinity and a residence time of ∼73 min, for the human A3R and 1.7 μΜ affinity for the human A2BR while not being toxic. Strikingly, the 2-methyl analog of 10b, 15b, had no significant affinity. Docking calculations and molecular dynamics simulations of the ligands inside the orthosteric binding area suggested that the 2-methyl group in 15b hinders the formation of hydrogen bonding interactions with N6.55 which are considered critical for the stabilization inside the orthosteric binding cavity. We, therefore, demonstrate that 10a is a novel scaffold for the development of high affinity AR ligands. From the mutagenesis experiments the biggest effect was observed for the Y2717.46A mutation which caused an ∼10-fold reduction in the binding affinity of 10b.  相似文献   
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Implantation of parathyroid carcinoma along fine needle aspiration track   总被引:1,自引:0,他引:1  
Introduction Fine needle aspiration cytology is not a commonly employed diagnostic modality in the diagnosis of parathyroid tumors.Case report A 28 year old lady being followed-up for 5 years after en bloc resection of a parathyroid carcinoma presented with a nodule in the lower neck, away from the parathyroidectomy scar. The 1 cm isolated nodule was located in the muscular and subcutaneous plane and corresponded to the needle track of FNA performed on a neck nodule before the parathyroidectomy. On evaluation, she had mild hypercalcemia and high normal serum parathyroid hormone levels. FNAC and histology including immunohistochemistry for Chromogranin A after local excision of the nodule confirmed the nodule to be a recurrent parathyroid carcinoma along the needle track.Discussion To the best of the authors’ knowledge, this is only the second case of needle track implantation after FNA in parathyroid carcinoma reported to date. This case highlights the risk of engraftment of parathyroid tissue after FNA and cautions against the use of FNA as a preoperative diagnostic modality for the evaluation of parathyroid lesions.Drs. Agarwal and Dhingra have contributed equally, as joint first authors.  相似文献   
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