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1.
Eighty-seven consecutive patients with metastatic breast cancer were treated with aminoglutethimide plus hydrocortisone. All patients were postmenopausal and had progressive disease following prior chemotherapy and endocrine therapy. Eighty-five women were evaluable for drug response. One patient showed complete remission and 14 patients partial response, for an overall response rate of 17%. The median duration of response was 11+ months. The response rate was highest in the presence of soft tissue involvement (36%). The most common side effects were transient skin rash, lethargy, and dizziness. Two patients discontinued treatment because of cutaneous allergy. Aminoglutethimide can be considered a moderately active agent when utilized as second- or third-line hormonal therapy.  相似文献   
2.
Numerous studies have convincingly shown that women with low bone mineral density have lower risk of breast cancer. As many risk factors for breast cancer are also prognostic factors, we hypothesized that women with breast cancer and low bone mineral density will have lower breast cancer recurrence rates than women with normal bone densities. A prospectively collected data base of breast cancer patients was used to identify postmenopausal Caucasian women. Their records were reviewed and 309 patients with complete follow‐up and bone density tests within 1 year of their surgery were identified. The outcome of patients with low bone density (t > ?1.0) was compared to the outcome for patients with normal bone density (t < ?1.1). Among the 193 patients with invasive breast cancers and low bone density, distant disease‐free survival at 5 years was 96% compared to 84% for 114 patients with invasive breast cancers and normal bone density (p = 0.0239). Local disease‐free survival was 94% for low bone density patients compared to 86% for patients with normal bone densities (p = 0.0794). Bone mineral density is a significant prognostic factor for postmenopausal Caucasian women with breast cancer. Low bone mineral density is associated with a lower local and distant rate of recurrence.  相似文献   
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The efficacy of alpha interferon (IFN-α) in the treatment of severe type II essential mixed cryoglobulinemia (EMC) has been reported previously. In some patients, the development of neutralizing antibodies to recombinant IFN-α (rIFN-α) can affect the clinical response achieved with rIFN-α; a second treatment with natural IFN-α preparations may reinduce the clinical response. In the present study the ability of leukocyte IFN (LeIFN) to restore the response was investigated from a pharmacodynamic viewpoint. Specifically, the pharmacodynamic profiles of different IFN-α preparations were studied by measuring the serum neopterin levels and the levels of expression of protein MxA mRNA in in vivo peripheral blood mononuclear cells in two patients with EMC whose resistance to rIFN-α2a treatment increased concomitantly with the development of neutralizing antibodies. These markers were measured before injection and at 24 and 48 h after a single injection of rIFN-α2a, consensus IFN [(C)IFN], or LeIFN. No increase or only a slight increase in MxA mRNA levels was detectable after administration of rIFN-α2a or (C)IFN, whereas a significant increase (≥10-fold) in MxA mRNA expression was recorded following administration of LeIFN. The neutralizing antibodies to rIFN-α2a cross-react with (C)IFN. Sera from these patients neutralized most but not all of the subtypes present in the natural IFN-α (LeIFN) mixture, and no significant increase in neopterin levels was observed after these patients were switched to LeIFN treatment. In summary, the data demonstrate that the problem of neutralizing antibodies still exists and that LeIFN may induce an increase in the level of MxA mRNA expression but not an increase in neopterin levels in patients who are resistant to treatment with rIFN-α2a or (C)IFN.  相似文献   
5.
Paediatric choroid plexus carcinomas (CPC) and adrenocortical carcinomas (ACC) are exceedingly rare tumours, each occurring at an annual rate of 0.3 cases per million children or less. Although both tumour types are associated with Li-Fraumeni syndrome (LFS), the penetrance of germline TP53 mutations in CPC remains to be established. We report here a young boy without a family history of cancer who presented with CPC and subsequently ACC. Genetic testing revealed a novel de novo germline TP53 mutation (E285V). Neither tumour underwent loss of heterozygosity. Consistent with this observation, functional analyses demonstrated that E285V acts as a dominant negative mutant that is defective in regulating target gene expression, growth suppression and apoptosis. These results further strengthen the association between germline TP53 mutations and childhood CPC, even when occurring in the absence of familial tumour susceptibility.  相似文献   
6.
Twenty-four consecutive patients with nondysgerminomatous germ cell tumor of the ovary were treated after surgery with cisplatin, vinblastine, and bleomycin (PVB regimen). The cycle was repeated every 3 weeks for three to five courses. Fourteen patients had endodermal sinus tumor, and 10 had mixed germ cell tumors. Stage of disease (FIGO, 1986) was as follows: stage I, 6; stage IIc-IV, 17; and recurrence, 1 patient. All patients were monitored by alpha-fetoprotein and human chorionic gonadotropin. Only 1 patient had received previous chemotherapy. All 5 patients without residual disease and with negative marker levels in which PVB was used as adjuvant treatment were free of disease for a median duration of 59 months from the start of PVB. Of the 19 patients with measurable disease (evident disease or positive marker levels), complete remission was obtained in 16 (84%), but 5 of these relapsed. Therefore, treatment with PVB failed in 8 out of 19 patients (42%) with measurable disease. Toxicity was evident, but no patient died of it. Menses were regular in 11 patients whose initial surgery was conservative. PVB regimen is an effective but not a satisfactory treatment. The considerable failure rate of PVB treatment suggests the investigation of other regimens.  相似文献   
7.
The physiological role of steroid hormones in humans is well known, and the metabolic pathway and mechanisms of action are almost completely elucidated. The role of plant steroid hormones, brassinosteroids, is less known, but an increasing amount of data on brassinosteroid biosynthesis is showing unexpected similarities between human and plant steroid metabolic pathways. Here we focus our attention on the enzyme 5alpha-reductase (5alphaR) for which a plant ortholog of the mammalian system, DET2, was recently described in Arabidopsis thaliana. We demonstrate that campestenone, the natural substrate of DET2, is reduced to 5alpha-campestanone by both human 5alphaR isozymes but with different affinities. Solanum malacoxylon, which is a calcinogenic plant very active in the biosynthesis of vitamin D-like molecules and sterols, was used to study 5alphaR activity. Leaves and calli were chosen as examples of differentiated and undifferentiated tissues, respectively. Two separate 5alphaR activities were found in calli and leaves of Solanum using campestenone as substrate. The use of progesterone allowed the detection of both activities in calli. Support for the existence of two 5alphaR isozymes in S. malacoxylon was provided by the differential actions of inhibitors of the human 5alphaR in calli and leaves. The evidence for the presence of two isozymes in different plant tissues extends the analogies between plant and mammalian steroid metabolic pathways.  相似文献   
8.
Mouse models have provided important insight into the in vivo significance of upstream and downstream signals that regulate the p53 tumour suppressor. One important lesson learned from these models is that negative regulators of p53 are critical in vivo modulators of p53 activity. Additionally, upstream regulators of p53 activity, such as p19(Arf) and Atm, are themselves critical tumour modifiers/suppressors. The presence of multiple positive regulators of p53 and numerous downstream targets indicates a redundancy that ensures activation of the p53 pathway. Importantly, p53 plays a prominent role as a tumour suppressor in vivo by virtue of its ability both to block cell cycle progression and to induce cell death. Finally, different p53 mutants have different properties in vivo. Three missense mutations have been generated at the p53 locus and all three exhibit unique differences in their ability to contribute to the tumour phenotype. Clearly, determining the levels of p53 inhibitors, and the typing of p53 mutations in human tumours should be performed to determine the best avenue for treatment.  相似文献   
9.
The results of endoscopic and surgical treatment in 21 patients affected by acute biliary pancreatitis are reported. All patients were managed according to the same protocol. Once the diagnosis was formulated (pain, serum amylase, ultrasonography, cholestasis and/or cholangitis) and the severity evaluated (Ranson's criteria, glucose and urea levels), the 21 patients underwent endoscopic retrograde cholangiopanctratography--within 24 hours in 8 patients (predicted severe disease) or within 72 hours in 13 patients (predicted mild disease). Endoscopic sphincterotomy was performed in 18 patients with stones in the common bile duct and was successful in 94.5% (17 patients: 3 patients underwent more than one session to confirm or achieve clearance of the duct). The morbidity rate associated with endoscopic sphincterotomy was 16% (3 patients: 2 haemorrhages, 1 perforation). There were no deaths. Cholecystectomy was performed in 16 patients within 2-9 weeks of the initial attack of acute biliary pancreatitis. There were 3 minor complications (respiratory, laparotomy, urinary infection), no major intraoperative or postoperative morbidity, and no mortality. Acute biliary pancreatitis is still associated with significant morbidity and mortality, but can be managed safely with combined medical, endoscopic and surgical treatment.  相似文献   
10.
Familial adenomatous polyposis is a hereditary clinical syndrome characterised by the presence of numerous adenomatous polyps of the colon and rectum and by lesions in other organs. The disease affects various different tissues and characteristically presents a variable biological and clinical behaviour. Colon polyps are precancerous lesions and the certainty of their malignant evolution within the 3rd-4th decades of life is now practically an established, extensively documented fact. Recently, new methods of genetic screening, prevention and early diagnosis and, as a result, more advanced treatment protocols have been introduced in clinical practice, thus offering young patients diagnosed as suffering from familial adenomatous polyposis better prospects and a better quality of life. The patient in our case came in for medical observation for abdominal pain experienced close to the scar of a previous appendectomy and for the presence of an abdominal tumefaction on the same side. Initially the patient underwent surgical resection of the growth that proved to be a desmoid tumour of the abdominal wall. The results of the pathology examination and the patients' long-term disease and family history led to a presumptive diagnosis of familial adenomatous polyposis, which was then confirmed by the appropriate instrumental examinations. Genetic tests on the patient's relatives yielded the same diagnosis in some of them. On the basis of our personal experience and a thorough review of the literature we can safely state that no medical treatment currently available is capable of reducing, let alone definitively eliminating colon polyps. To date, then, the therapeutic options most commonly adopted are colectomy with ileo-rectal anastomosis and total conservative proctocolectomy with an ano-ileal pouch anastomosis. These two types of surgical procedures yield different results in terms of functional capability and oncological radicality with their respective repercussions on the patient's quality of life. The choice of the most appropriate surgical procedure is made on the basis of a series of parameters such as age, site of the polyps, number of polyps, degree of cell atypia of the polyps, and patient willingness to undergo regular check-ups. The current tendency advocated by the various authors is to perform a total colectomy as soon as possible.  相似文献   
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