Search PubMed⌕ Search

Biomedical subjects

G Hortobagyi

Publications and source records attributed to G Hortobagyi.

At least 19 recordsLinked to original sources
PubMed1998

Markers of bone resorption in patients treated with pamidronate.

Pyridinoline (PYD), deoxypyridinoline (DPD), and N-telopeptide (NTX) are markers of bone resorption. In cancer patients with bone metastases, NTX is more often elevated than either of the pyridinolines. Bisphosphonates inhibit osteoclasts and their treatment decreases skeletal complications of malignancy. The aim of this study was to correlate urinary PYD, DPD, and NTX levels with clinical events in patients receiving pamidronate. 25 cancer patients with lytic bone disease were treated with monthly pamidronate combined with endocrine or chemotherapy; 27 others were on placebo. Twenty-four hour urines were collected at baseline, 1, 3 and 6 months. NTX values were determined by enzyme-linked immunosorbent assay (ELISA); PYD and DPD values were determined by reverse phase high performance liquid chromatography (HPLC). Two hour urines were also collected weekly for 21 patients. The greatest difference as a result of pamidronate treatment was observed in NTX values. Maximum suppression was achieved 2 weeks after treatment. Of the 25 patients who received pamidronate, 21 had initially elevated NTX values. 12 of the 21 finished with normal NTX values, whilst 9/21 had NTX values which remained abnormally elevated. The proportions of patients with fractures between these two subgroups approached statistical significance (P = 0.07) while the proportions with bony disease progression were significant (P = 0.03, Fisher's exact test). Measuring NTX levels appears useful in monitoring bisphosphonate therapy of bone metastases. The goal of treatment should be to normalise NTX excretion.

Aged↗
PubMed1998

Update on endocrine therapy for breast cancer.

The choice of endocrine agent for breast cancer depends on the menopausal status of the patient, the stage of disease, prognostic factors, and the toxicity profile of the agent. Endocrine therapies are typically given sequentially, with the least toxic therapy given first. Tamoxifen is considered first-line endocrine therapy for all stages of breast cancer. New antiestrogens in development include nonsteroidal agents related to tamoxifen and pure steroidal antiestrogens. Luteinizing hormone-releasing hormone agonists are an effective form of endocrine therapy for premenopausal women with advanced breast cancer, and aromatase inhibitors are effective in postmenopausal women. Newer and more selective aromatase inhibitors that are p.o. active and have improved side-effect profiles have been developed. Recent trials have found these agents to improve survival in comparison to the progestins; thus, aromatase inhibitors are replacing progestins as second-line therapy for metastatic disease. Current trials are examining the potential role of aromatase inhibitors as first-line therapy for metastatic disease or as adjuvant therapy for early disease. The antiprogestins and antiandrogens studied thus far have had only limited success in breast cancer clinical trials.

Antineoplastic Agents, Hormonal↗
PubMed1997

Progressive decrease in nuclear retinoic acid receptor beta messenger RNA level during breast carcinogenesis.

Some of the nuclear retinoic acid receptors (RARs) alpha, beta, and gamma and retinoid X receptors (RXRs) alpha, beta, and gamma are thought to mediate the effects of retinoids on cell growth, differentiation, and apoptosis and thereby prevent breast carcinogenesis. We analyzed the expression of mRNAs for the three RARs and RXR-alpha in histological sections of specimens from 70 breast cancer patients, which included adjacent normal tissue, ductal carcinoma in situ, and invasive cancer, using in situ hybridization. RARs alpha, beta, and gamma and RXR-alpha were expressed in 98.1, 98.0, 93.0, and 100% of the adjacent normal tissues. Significant decreases in the number of cases expressing RAR-beta were observed among ductal carcinoma in situ (83.1%) and invasive carcinomas (51.6%), especially among the poorly differentiated cases (77.4 and 35.7 %, respectively). No relationship was found between the expression of estrogen receptor and RAR-beta. These results implicate decreases in RAR-beta expression in breast cancer development and suggest that they are independent of estrogen receptor status.

Breast↗
PubMed1997

Chemotherapy-induced neutropenia and fever in patients with metastatic breast carcinoma receiving salvage chemotherapy.

BACKGROUND: Chemotherapy-induced neutropenia and associated fever and infection are the most common complications of systemic chemotherapy. In this retrospective analysis, the authors evaluated the incidence of neutropenic fever, infection, and mortality in relation to the level of neutropenia, performance status, course number of chemotherapy, bone marrow metastasis, and age among patients with metastatic breast carcinoma receiving salvage chemotherapy. METHODS: A total of 174 patients with previously treated metastatic breast carcinoma enrolled on 4 consecutive Phase II protocols were evaluated. RESULTS: Twenty-three percent of the patients had an episode of neutropenic fever (41 episodes among 40 patients). The incidence of neutropenic fever did not increase until the absolute neutrophil count (ANC) had decreased to less than 500/microL, and then fever incidence had a linear relationship with decreasing ANC (linear trend, P < 0.01). A source of infection was documented in 59% of the neutropenic fever episodes. The incidence of infection did not increase significantly until the ANC had decreased to less than 250/microL (P < 0.01). The risk of neutropenic fever and infection was also significantly higher when patients had poor performance status or were undergoing the initial courses of chemotherapy. Patients with bone marrow metastases also had a higher frequency of fever, infection, and death, but these differences were not statistically significant. CONCLUSIONS: For patients with metastatic breast carcinoma receiving salvage chemotherapy, the risk of fever increases with decreasing ANC, but the risk of infection does not increase significantly until ANC decreases to less than 250/microL. Poor performance status, initial courses of chemotherapy, and bone marrow metastases further increase the risk of fever, infection, and death.

Adult↗
PubMed1997

Phase II study of semisynthetic paclitaxel in metastatic breast cancer.

The aim of this phase II study was to characterise the efficacy and toxicity of semisynthetic paclitaxel in patients with metastatic breast cancer. Eligible patients had measurable disease and had been treated with one prior chemotherapy regimen either as adjuvant or for metastatic disease. Semisynthetic paclitaxel was given at a dose of 175 mg/m2 over 3 h every 21 days with dexamethasone, cimetidine and diphenhydramine premedications. 31 patients were entered. All were evaluable for toxicity. 30 patients were evaluable for response because 1 patient was lost to follow-up after receiving one cycle. One patient achieved a complete response and 10 patients achieved partial responses for an overall response rate (CR + PR) of 37% (95% confidence interval 20-56%). 17 patients (55%) experienced at least one episode of grade 3 or 4 neutropenia. There were two episodes of febrile neutropenia complicating 155 cycles of therapy. One of these resulted in a treatment-related death in a patient with pulmonary metastasis. 3 patients required dose reductions for grade 3 sensory neuropathy. Our study shows that the antitumour activity and toxic effects of semisynthetic paclitaxel appear to be identical to the naturally occurring product.

Adult↗
PubMed1997

Use of Truquant BR radioimmunoassay for early detection of breast cancer recurrence in patients with stage II and stage III disease.

PURPOSE: The Truquant BR radioimmunoassay (RIA) (Biomira Diagnostics Inc, Rexdale, Canada) uses the monoclonal antibody B27.29 to quantitate the MUC-1 gene product (CA 27.29 antigen) in serum. We evaluated CA 27.29 antigen in a controlled, prospective clinical trial for its ability to predict relapse in stage II and stage III breast cancer patients. PATIENTS AND METHODS: Over a 2-year period, 166 patients who had completed therapy for stage II (80.1%) or III (19.9%) breast cancer and were clinically free of disease were serially tested for CA 27.29 antigen levels. The study was double-masked and cancer recurrence was documented based on clinical findings. Patients with two consecutive CA 27.29 antigen test results above the upper limit of normal were considered positive. RESULTS: The Truquant BR RIA had a sensitivity of 57.7%, specificity of 97.9%, positive predictive value of 83.3%, and negative predictive value of 92.6%. The recurrence rate was 15.7%. A Cox regression analysis showed that the only variable to correlate with recurrent disease was the CA 27.29 antigen test result. Patients with a positive test result had increased odds of having a recurrence (odds ratio, 6.8; P < .00001). The test was effective in predicting recurrence in patients with both distant and locoregional disease. In a subgroup of patients with bone pain, CA 27.29 antigen level was found to identify reliably patients who would subsequently develop recurrent disease. CONCLUSION: These data demonstrate that the Truquant BR RIA can be used as an aid to predict recurrent breast cancer in patients with stage II and III disease.

Adult↗
PubMed1997

Phase I/II study of dose-intense doxorubicin/paclitaxel/cyclophosphamide with peripheral blood progenitor cells and cytokine support in patients with metastatic breast cancer.

Relapse following complete remission achieved with a single course of high-dose chemotherapy continues to be the main cause of treatment failure in patients with metastatic breast cancer. A phase I/II trial was initiated that combined the two most active drugs against breast cancer, doxorubicin and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ), with cyclophosphamide, and delivered four cycles of these drugs with peripheral blood progenitor cells (PBPCs) and granulocyte colony-stimulating factor support in an outpatient setting. Patients with untreated metastatic breast cancer received two cycles of doxorubicin 60 mg/m2 and paclitaxel 200 mg/m2. During recovery from the second cycle, PBPCs were harvested. Responding patients were then admitted for a day to receive escalating-dose doxorubicin, paclitaxel, and cyclophosphamide followed by PBPC reinfusion on day 3 as outpatients. Seventeen patients have been enrolled to date. Ten patients completed treatment and received 34 cycles of high-dose chemotherapy every 21 days (range, 21 to 28 days). The median age was 47 years (range, 26 to 56 years) and the median number of metastatic sites was two (range, one to three). Five patients had received adjuvant chemotherapy (four cyclophosphamide/methotrexate/5-fluorouracil and one mitoxantrone-based). The most common toxic reactions were nausea and vomiting (75% of courses) and neurosensory (50% of courses). No patients had a decreased ejection fraction or overt congestive heart failure. Ten patients underwent cardiac biopsy (median doxorubicin, 253 mg/m2; range, 120 to 312 mg/m2); only one showed grade 1 cytotoxic changes with doxorubicin 240 mg/ m2. Six patients were admitted for neutropenic fever. Eight of 10 patients responded (two pathologically confirmed complete remissions in liver). At these doses, four cycles of doxorubicin, paclitaxel, and cyclophosphamide with PBPC and granulocyte colony-stimulating factor support every 21 days was well tolerated and showed evidence of activity. Enrollment at higher dose levels continues so that maximum tolerated dose can be defined.

Adult↗
PubMed1996

Results of MDR-1 vector modification trial indicate that granulocyte/macrophage colony-forming unit cells do not contribute to posttransplant hematopoietic recovery following intensive systemic therapy.

To formally test the hypothesis that the granulocyte/macrophage colony-forming unit (GM-CFU) cells can contribute to early hematopoietic reconstitution immediately after transplant, the frequency of genetically modified GM-CFU after retroviral vector transduction was measured by a quantitative in situ polymerase chain reaction (PCR), which is specific for the multidrug resistance-1 (MDR-1) vector, and by a quantitative GM-CFU methylcellulose plating assay. The results of this analysis showed no difference between the transduction frequency in the products of two different transduction protocols: "suspension transduction" and "stromal growth factor transduction." However, when an analysis of the frequency of cells positive for the retroviral MDR-1 vector posttransplantation was carried out, 0 of 10 patients transplanted with cells transduced by the suspension method were positive for the vector MDR-1 posttransplant, whereas 5 of 8 patients transplanted with the cells transduced by the stromal growth factor method were positive for the MDR-1 vector transcription unit by in situ or in solution PCR assay (a difference that is significant at the P = 0.0065 level by the Fisher exact test). These data suggest that only very small subsets of the GM-CFU fraction of myeloid cells, if any, contribute to the repopulation of the hematopoietic tissues that occurs following intensive systemic therapy and transplantation of autologous hematopoietic cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

Technical approach for the study of the genetic evolution of breast cancer from paraffin-embedded tissue sections.

We have optimized a technique that allows the study of numerous chromosomal loci (n = 20-50) from single paraffin-embedded tissue sections by microsatellite length polymorphism analysis. DNA samples from normal and breast cancerous tissue can be obtained from the same section by means of microdissection. This technique was further improved by subjecting DNA to several cycles of amplification with a degenerate (universal) primer and then with specific microsatellite primers. This amplified DNA was also used to screen for mutations in the p53 gene by means of PCR-SSCP. In addition adjacent tissue sections were used to assess specific chromosome copy number by interphase cytogenetic analyses (chromosome in situ hybridization) and to analyze expression of specific genes such as p53 and ERBB2. As an example of the use of our approach we performed a detailed chromosome 17 allelotypic analysis in 22 breast tumors (5 ductal carcinomas in situ, 13 invasive ductal carcinomas, and 4 invasive lobular carcinomas). We detected mutations in the p53 gene by PCR-SSCP in 36% of the samples. Samples with significant levels of p53 protein accumulation detected by immunohistochemistry were also positive for mobility shifts in the SSCP analysis. We observed that chromosome 17 allelic losses and imbalance occurred at as early a stage as ductal carcinoma in situ (DCIS). Although in some cases we observed allelic losses or imbalance affecting the 17p13 region, close to the p53 locus, several of the tumors showed dissociation between such loss or imbalance and p53 mutation. Lobular carcinomas were predominantly disomic for chromosome 17 in contrast with ductal tumors, which often showed polysomy for chromosome 17. This comprehensive approach correlating the tumor subtype, its allelotype, with specific chromosome copy number and specific gene mutations and expression in preinvasive or early invasive breast cancer lesions will potentially provide information of relevance for a better understanding of the multistep mechanisms of breast carcinogenesis.

Alleles↗
PubMed1995

Recent advances in the application of gene therapy to human disease.

PURPOSE: To review the recent advances in the application of genetic modification strategies to the therapy of human diseases for which a molecular defect is known. METHODS: A computerized data bank search, the minutes of the National Institutes of Health (NIH) Recombinant DNA Advisory Committee published in the Federal Record, and reports of human clinical trials were used as data sources for this review. Clinical trials included in this review were published in the literature or approved by the NIH Recombinant DNA Advisory Committee. STUDY SELECTION: Evaluations of the efficacy of genetic modification strategies in clinical trials in human and in animal models are summarized. The design and outcome of the genetic modification strategies employed are reviewed for 16 marking trials, 16 gene replacement trials for molecular deficiency diseases, 3 chemoprotection and 4 chemotherapy sensitization trials, 11 cancer vaccine trials, 2 antisense oligonucleotide trials, and 3 molecular immunotherapy trials. DATA SYNTHESIS: The marking trials have shown that residual leukemia cells in the infused autologous marrow can contribute to relapse following autologous bone marrow transplants. The use of genetic modification for the replacement of missing or deficient genes in severe combined immunodeficiency, familial hypercholesterolemia, and cystic fibrosis has been associated with encouraging results so far. Clinical genetic therapy trials involving cancer vaccines, antisense oligonucleotides, adoptive immunotherapy with genetically modified T cells, delivery vectors containing interleukin-1 receptor inhibitor for arthritis, replacement strategies for storage diseases, and genetic suppression of human immunodeficiency viral replication are just commencing. CONCLUSIONS: The clinical application of genetic modification techniques has thus far been successful in the beginning phases of this field. These early results suggest that continuation of gene therapy trials designed to correct the molecular changes that lead to disease states in humans is warranted. Evaluation of such clinical trials in the future may be based on the analysis of assays for short-term surrogate endpoints, as well as on the therapeutic outcomes of the trial, such as survival or remission.

Bone Marrow Transplantation↗
PubMed1994

Phase II study of deoxyspergualin in metastatic breast cancer.

We conducted a phase II trial of the novel immunomodulatory/cytotoxic agent 15-deoxyspergualin in patients with metastatic breast cancer who had failed treatment with front-line chemotherapy. Thirty-eight courses of treatment were administered to fourteen patients enrolled in this trial, 25 at a dose of 1800 mg/m2/d (dose level 0) and 13 at a dose of 2150 mg/m2/d (dose level +1) administered by continuous intravenous infusion for 5 days. Treatment was well tolerated with neuromuscular side-effects (myalgias, paresthesias) and granulocytopenia (nadir granulocyte count of 0.50-0.99 x 10(9)/l) in two and three courses, respectively, as the only grade III toxicities. The neuromuscular toxicity of deoxyspergualin is probably related to the occurrence of hypomagnesemia. No partial or complete responses were observed in this study. One patient achieved a minor response but had progressive disease 65 weeks after enrollment. The response was observed coincident with an increase in T4/T8 ratio in the peripheral blood. The median time to progression for the entire cohort was eight weeks (range, 4-65 weeks). There was no clinical evidence of immunosuppression and no decrease in total peripheral blood lymphocyte counts or helper T-cells was observed. At the doses and schedule employed in this trial, deoxyspergualin does not appear to have significant activity against metastatic breast cancer resistant to front-line chemotherapy. The correlation between hypomagnesemia and neuromuscular toxicity of deoxyspergualin is an intriguing, previously unknown observation and requires further investigation.

Adult↗
PubMed1994

Natural immunity in breast cancer patients during neoadjuvant chemotherapy and after surgery.

Breast cancer is the most common cancer in women. Surgery, and more recently neoadjuvant chemotherapy, are being utilized as the initial treatment for breast cancer; however little is known about their effects on the natural immune system. The natural immune system (natural killer [NK] cells) is thought to be important in immune surveillance, including protection from metastasis during the intravascular tumour seeding that occurs during surgery. To investigate the effects of surgery on the natural immune system, we studied the pre-operative and post-operative peripheral blood lymphocytes (PBL) of 10 patients with stage I or II breast cancer: there was a 71.6 +/- 25.3% post-operative reduction in NK cell function (P < 0.005, Student's paired t-test). To investigate the effects of neoadjuvant chemotherapy and surgery, we examined PBL from five patients with stage III breast cancer: NK cell function dropped 95.7 +/- 1.9% after neoadjuvant chemotherapy, and there was a further 51.0 +/- 23.4% decrease after surgery (P < 0.05, Student's paired t-test). Neither group of patients had decreased numbers of NK cells, changes in the percentage of T helper or suppressor cells, or alterations in the production of cytotoxic factor by NK cells. These findings suggest that the impairment in NK cell function reflects a defect in the ability of NK cells to recognize and/or bind to tumour target cells. We conclude that the initial treatment of breast cancer patients, whether it involves surgery alone or with neoadjuvant chemotherapy, profoundly impairs their natural immune system and could increase the risk of metastasis. Further studies are needed to delineate the mechanism of this derangement in natural immunity and possibly alter its course.

Adult↗
PubMed1993

Genetic therapy of human neoplastic disease.

Molecular biology has provided clinical investigators and basic scientists with the tools to identify those changes present within neoplastic hematopoietic and epithelial cells that lead to the evolution of unregulated patterns of cell growth. This information has made possible the development of therapy that involves genetic modification of either the normal hematopoietic cells (for chemoprotection), or the tumor cells themselves to suppress the growth of these cells. This article will summarize the clinical and laboratory data that is evolving in this area.

Animals↗
PubMed1992

Chromosome in situ hybridization on formalin-fixed mammary tissue using non-isotopic, non-fluorescent probes: technical considerations and biological implications.

Fluorescent in situ hybridization techniques have provided an important tool for interphase cytogenetic studies of human neoplasms. However, these techniques are difficult to use on formalin-fixed archival tissue sections. We describe here a non-fluorescent, non-isotopic in situ hybridization (ISH) approach that is easily applicable to paraffin-embedded breast tissue sections. The technical steps that must be monitored and individualized to optimize signal generation and detection are discussed. This ISH technique has several advantages over fluorescent detection methods. The signal obtained can be viewed using an ordinary light microscope and does not fade with time. More importantly, the signal is observed and analyzed in the context of tissue morphology. The technique permits detection of numerical chromosomal abnormalities not only in malignant but also in apparently normal and potentially premalignant mammary tissue. This may allow identification of focal genetic abnormalities as well as field-defects and enable analysis of their evolution during the multistep transformation to mammary neoplasm. This technique is also suitable for analysis of tumor heterogeneity and the correlation of numerical chromosomal aberrations with histologic, immunocytochemical, and clinical features of breast tumors.

Breast↗
PubMed1992

Vertebral osteomyelitis mimicking bone metastasis in breast cancer patients.

Vertebral osteomyelitis can be a diagnostic pitfall for physicians, since it is protean and often subtle in its clinical presentation. It can coexist with metastatic lesions or mimic vertebral bone metastasis. When it occurs in patients with breast cancer, who are prone to have bone metastasis, it can present perplexing diagnostic problems. Misdiagnosing vertebral osteomyelitis as bone metastasis or vice versa results in delayed diagnosis and inappropriate treatment and may cause serious morbidity. We emphasize this problem by presenting the cases of two patients with breast cancer whose clinical course was complicated by vertebral osteomyelitis. When the clinical course of breast cancer is different from this usual presentation, a different process should be suspected, and histologic diagnosis should be promptly sought. Fine-needle aspiration biopsy and culture of suspicious-appearing bony lesions is recommended as a rapid and reliable method of establishing a definite diagnosis in this circumstance.

Breast Neoplasms↗
PubMed1992

Inflammatory breast cancer: a review.

PURPOSE: The natural history of inflammatory breast cancer and the recent advances in its management were reviewed. DESIGN: The English medical literature from 1924 to 1990 was reviewed using the Cancerline and Medline retrieval systems, and through a manual review of bibliographies of identified articles. RESULTS: The majority of patients with inflammatory breast cancer treated only with local therapies died 18 to 24 months after diagnosis. A combined modality approach with chemotherapy, surgery, and radiation therapy has improved disease-free and overall survival rates for inflammatory breast cancer. Approximately 35% to 55% of patients treated with combined modality regimens remain disease-free and alive at 5 years. CONCLUSION: Induction combination chemotherapy administered with radiation therapy, mastectomy, both, or with additional chemotherapy favorably alters the natural history of inflammatory breast cancer. New drug combinations and high-dose chemotherapy with autologous bone marrow support are being evaluated to improve further patient survival.

Breast Neoplasms↗