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Query: UMLS:C0027651 (
tumor
)
685,946
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A case of 35-year-old woman with parathyroid cancer is presented. Five years ago she underwent surgery for follicular thyroid cancer. Parathyroid cancer was evidenced by palpable, solid, irregularly shaped cervical
tumor
5 cm in diameter. The patient had severe hyperparathyroidism confirmed by biochemical findings of hypercalcemia reaching 16 mg%, hypophosphatemia and hyperphosphatasemia. Serum parathormone level was 23-fold higher than the norm. These findings were accompanied by polyuria, polidypsia, symptoms of bone damage and renal calcification. After the surgery the patient's condition improved significantly despite persistent hyperparathyroidism. The level of parathormone decreased, but was still 11 times higher than the norm. Two months after the surgery she noticed a single node on her neck. The patient was re-operated for recurrence of parathyroid cancer. Serum parathormone level was then 6-8 times above the norm. Medical treatment with furosemide, calcitonin and biphosphonate resulted in normalization of calcemia and phosphatemia. Further management will aim at localization of foci of hyperactive parathyroid tissue in order to enable radical reoperation. The case is reported because of rare occurrence of parathyroid carcinoma as well as because the carcinoma occurred in a patient who previously had follicular thyroid cancer. There are no reports of coexistence of these two neoplasms in available literature.
Med Sci
Monit
PMID:Coexistence of parathyroid carcinoma and non-medullary carcinoma of the thyroid. 1138 24
Doxorubicin and other anthracyclines are an important class of agents for the treatment of early and advanced stage breast cancer, but produce substantial acute and chronic toxicities. One strategy for reducing anthracycline-associated toxicity is packaging them in liposomes. Liposomes are closed vesicular structures that envelop water-soluble molecules. They may serve as vehicles for delivering cytotoxic agents more specifically to
tumor
, and limit exposure of normal tissues to the drug. Liposomal anthracyclines are more effective and less toxic in a number of preclinical models compared with conventional anthracyclines. Several liposomal anthracyclines have been extensively studied in humans with a variety of cancer types, including TLC D-99 (Myocet; The Liposome Company,
Elan
Corporation, Princeton, NJ), liposomal daunorubicin (Daunoxome; NeXstar Pharmaceuticals, Inc, San Dimas, CA), and pegylated liposomal doxorubicin (Doxil; Alza Pharmaceuticals, Palo Alto, CA, Caelyx; Schering Corporation, Kenilworth, NJ). Although none of these agents are currently approved for the treatment of breast cancer in the United States, the liposomal doxorubicin preparations seem to have comparable activity and less cardiac toxicity than conventional doxorubicin. Furthermore, they have been safely combined with other cytotoxic agents, including cyclophosphamide, 5-fluorouracil, vinorelbine, paclitaxel, and docetaxel. Further studies will be required do determine their role in the treatment of breast cancer.
...
PMID:Liposomal anthracyclines for breast cancer. 1155 28
Reactive oxygen species are known to be potentially dangerous, but are also needed for signal-transduction pathways.
Tumor
cells have relatively low amounts of superoxide dismutase (SOD), which quenches superoxide anion (O2(-*)), and as a result of a higher level of aerobic metabolism, higher concentrations of O2(-*) , compared to normal cells. But this may not be true of all
tumor
cells. Some
tumor
cells have relatively higher amounts of vitamin E, a potent anti-oxidant, and a higher level of anaerobic metabolism, resulting in a balance that is tilted more towards higher anti-oxidant capacity. In both instances of higher aerobic and anaerobic metabolism methods designed to augment free radical generation in
tumor
cells can cause their death. It is suggested that free radicals and lipid peroxides suppress the expression of Bcl-2, activate caspases and shorten telomere, and thus inducing apoptosis of
tumor
cells. Ionizing radiation, anthracyclines, bleomycin and cytokines produce free radicals and thus are useful as anti-cancer agents. But they also produce many side-effects. 2-methoxyoestradiol and polyunsaturated fatty acids (PUFAs) inhibit SODs and cause an increase of O2(-*) in
tumor
cells leading to their death. In addition, PUFAs (especially gamma-linolenic acid), 2-methoxyoestradiol and thalidomide may possess anti-angiogenic activity. This suggests that free radicals can suppress angiogenesis. Limited clinical studies done with gamma-linolenic acid showed that it can regress human brain gliomas without any significant side-effects. Thus, PUFAs, thalidomide and 2-methoxyoestradiol or their derivatives may offer a new radical approach to the treatment of cancer.
Med Sci
Monit
2002 Apr
PMID:A radical approach to cancer. 1195 Oct 81
The Fragile Histidine Triad (FHIT) Gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a
tumor
suppressor gene involved in different
tumor
types. Abnormalities of the FHIT locus were found in many established cancer cell lines and tumors including breast cancer. In sporadic breast cancer, loss of heterozygosity within the FHIT gene has been observed at different frequencies and has been correlated with tumor progression. Aberrant FHIT transcripts have been reported in breast cancer. Furthermore, Fhit protein loss is correlated with prognosis. We summarized the research advances of FHIT genetic, epigenetic change and aberrant Fhit protein expression in breast cancer. Fhit protein may be a novel prognostic factor for breast cancer. FHIT gene therapy may potentially be clinically useful for treatment of breast cancer, suggesting further research involving FHIT introduction should be performed in breast cancer.
Med Sci
Monit
2002 Jul
PMID:The Fragile Histidine Triad gene and breast cancer. 1211 13
The antineoplastic enzyme L-asparaginase is commonly used for the induction of remission in acute lymphoblastic leukemia (ALL). L-Asparagine is an essential amino acid for many lymphoid
tumor
cells and L-asparaginase catalyzes its conversion to L-aspartic acid and ammonia. The dosage of this highly toxic drug is individualized based on the body surface area of the patient, but monitoring of L-asparaginase activity during the L-asparaginase therapy is not commonly used. We measured L-asparaginase activity in the serum of ten children (aged 3-13 y) with ALL (ALL NOPHO-92 standard or intermediate risk groups) during their L-asparaginase therapy. L-asparaginase was given 30,000 IU/m2 IM during days 37-46 of the induction therapy and no other chemotherapeutic drug except for prednisone was given at the same time. We observed that this dosage schedule resulted in almost 6-fold differences in the serum activity of L-asparaginase between the patients. There was also a relationship between the area under the L-asparaginase activity-time curve (AUC) and even peak L-asparaginase activity in serum during the enzyme therapy and neutropenia after the therapy in the patients: the higher the AUC or peak value was, the more severe was the neutropenia in the patients after treatment. Monitoring L-asparaginase in serum could be useful in optimization of the therapy with this toxic drug.
Ther Drug
Monit
2002 Aug
PMID:Serious neutropenia in ALL patients treated with L-asparaginase may be avoided by therapeutic monitoring of the enzyme activity in the circulation. 1214 34
The aim of this study is to define risk factors for severe complications following anatomical liver resections. The study material consists of the first 50 patients (26 women, 24 men, at mean age 50.6 years) treated at 3rd Department of Surgery 2nd Faculty of Medicine, Medical University in Warsaw. The indications for resection included benign
neoplasm
in 19 cases and malignancy in 31 cases. All the patients underwent anatomical liver resection in accordance with Couinaund's segmental division. In order to define prognostic factors for severe postoperative complications, a multi-factor statistical analysis was conducted. The following parameters were analysed: patient's age, the levels of bilirubin, total protein, albumin, prothrombin time, kaolin-kephalin time, range of resection and blood loss during operation. Eleven patients (22%) died in postoperative period. In 8 cases the death was caused by liver failure. Statistical analysis showed that blood loss, albumin level on fifth postoperative day and kaolin-kephalin time before and after surgery are independent risk factors predisposing to the development of complications.
Med Sci
Monit
2001 May
PMID:Risk factors for morbidity following liver surgery. 1221 40
We have summarized the molecular and cellular events involved in nickel (Ni) compound induced carcinogenesis. The major hypothesis for nickel carcinogenic action has involved the ability of the Ni compound to deliver high concentrations of Ni intracellularly, enter the nucleus and interact with chromatin. Ni has been found to selectively damage heterochromatin, and a major action of Ni is its ability to silence the expression of genes located near heterochromatin by inducing a loss of histone H4 and H3 acetylation and DNA hypermethylation. When Ni silences critical genes, such as
tumor
suppressor genes, the cell is altered to a greater state of neoplastic transformation. The carcinogenic hazard of Ni compounds has been directly related to the ability of that Ni compound to raise the intracellular Ni ions. The mechanisms of Ni-induced gene silencing will be discussed. However, recently it has been found that soluble Ni ions can interact with the cell surface receptors and activate cell signaling resulting in the induction of a variety of cellular genes. In particular, the Ca and hypoxia inducible factor pathway is activated in all cells exposed to soluble Ni ions. In the case of HIF-1 induction, a cell is now equipped with the expression of a variety of genes that will allow the cell to survive the lack of oxygen and thus should enable a previously initiated cancer cell to progress into a full malignant state and metastasize. These new findings support the view that soluble Ni ions exhibit carcinogenic potential by activating cell promotion and lend strength to the epidemiological data showing soluble Ni to be associated with cancer risk in Ni refinery workers.
J Environ
Monit
2003 Apr
PMID:Molecular mechanisms of nickel carcinogenesis: gene silencing by nickel delivery to the nucleus and gene activation/inactivation by nickel-induced cell signaling. 1272 58
A small difference in decision-making causes a big impact on the long-term outcome in cancer treatment. Novel methods such as preoperative systemic treatment or sentinel node biopsy (SNB) may alter the decision-trees in primary breast cancer management. Recent data showed that preoperative chemotherapy drives pathological complete response (pCR) that implies long-term relapse-free, for about 25% to 30% of early breast cancer patients. In fact, preoperative systemic therapy has come to be used regardless of the
tumor
stage. From the point of the clinical trial, pCR can be recognized as a new endpoint, which promises to speed up new therapy development. Therefore, it is crucial to consider new paradigms including preoperative therapy in the decision-tree. There are several criticisms regarding the preoperative therapy, such as a possibility of over-treatment, however these issues might be resolved by changing the concept or procedures slightly. For instance, if SNB is conducted before the treatment, the over-treatment issue can be eliminated. In this article, we will discuss the changes in decision-tree and paradigms for primary
Med Sci
Monit
2003 May
PMID:Decision tree and paradigms of primary breast cancer: changes elicited by preoperative therapy. 1276 67
Many attempts have been made to achieve good selectivity to targeted
tumor
cells by preparing specialized carrier agents that are therapeutically profitable for anticancer therapy. Among these, liposomes are the most studied colloidal particles thus far applied in medicine and in particular in antitumor therapy. Although they were first described in the 1960s, only at the beginning of 1990s did the first therapeutic liposomes appear on the market. The first-generation liposomes (conventional liposomes) comprised a liposome-containing amphotericin B, Ambisome (Nexstar, Boulder, CO, USA), used as an antifungal drug, and Myocet (
Elan
Pharma Int, Princeton, NJ, USA), a doxorubicin-containing liposome, used in clinical trials to treat metastatic breast cancer. The second-generation liposomes ("pure lipid approach") were long-circulating liposomes, such as Daunoxome, a daunorubicin-containing liposome approved in the US and Europe to treat AIDS-related Kaposi's sarcoma. The third-generation liposomes were surface-modified liposomes with gangliosides or sialic acid, which can evade the immune system responsible for removing liposomes from circulation. The fourth-generation liposomes, pegylated liposomal doxorubicin, were called "stealth liposomes" because of their ability to evade interception by the immune system, in the same way as the stealth bomber was able to evade radar. Actually, the only stealth liposome on the market is Caelyx/Doxil (Schering-Plough, Madison NJ, USA), used to cure AIDS-related Kaposi's sarcoma, resistant ovarian cancer and metastatic breast cancer. Pegylated liposomal doxorubicin is characterized by a very long-circulation half-life, favorable pharmacokinetic behavior and specific accumulation in
tumor
tissues. These features account for the much lower toxicity shown by Caelyx in comparison to free doxorubicin, in terms of cardiotoxicity, vesicant effects, nausea, vomiting and alopecia. Pegylated liposomal doxorubicin also appeared to be less myelotoxic than doxorubicin. Typical forms of toxicity associated to it are acute infusion reaction, mucositis and palmar plantar erythrodysesthesia, which occur especially at high doses or short dosing intervals. Active and cell targeted liposomes can be obtained by attaching some antigen-directed monoclonal antibodies (Moab or Moab fragments) or small proteins and molecules (folate, epidermal growth factor, transferrin) to the distal end of polyethylene glycol in pegylated liposomal doxorubicin. The most promising therapeutic application of liposomes is as non-viral vector agents in gene therapy, characterized by the use of cationic phospholipids complexed with the negatively charged DNA plasmid. The use of liposome formulations in local-regional anticancer therapy is also discussed. Finally, pegylated liposomal doxorubicin containing radionuclides are used in clinical trials as
tumor
-imaging agents or in positron emission tomography.
...
PMID:From conventional to stealth liposomes: a new frontier in cancer chemotherapy. 1290 76
Radiofrequency ablation (RFA) is an image guided percutaneous procedure using thermal energy that is used to treat malignant lesions in various organs including liver, breast and lungs. It has also been used bronchoscopically to treat endobronchial tumors. Current passing through tissue from the active electrode leads to ion agitation, which is converted by means of friction into heat leading to irreparable cellular damage and coagulation necrosis. The potential benefits include decreased cost and morbidity, treating patients who are not surgical candidates due to age, co-morbidity or extent of disease and the possibility of performing the procedure on an outpatient basis. The aim is usually to reduce
tumor
size. Whether it can be used with a curative intent in well localized primary tumors remains to be determined by well designed studies. However, caution should be exercised because selective
tumor
resection is not the gold standard to treat potentially resectable lung malignancies that are treated with lobectomy. Obviously, lung volume reduction surgery combined with
tumor
resection has challenged this approach. RFA might be the treatment of choice for multiple lung metastases that are usually approached surgically for long-term remission. A specific indication may also be bilateral pulmonary metastases. Other potential applications might be
tumor
size reduction by a non-surgical procedure followed by adjuvant chemotherapy. Currently, these thoughts remain only speculations, until proven by clinical trials with medium to long-term follow up. Furthermore, the risk of this procedure for pulmonary application has to be better defined.
Med Sci
Monit
2003 Nov
PMID:Radiofrequency heat ablation for lung tumors: potential applications. 1458 81
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