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Biomedical subjects

T J Lynch

Publications and source records attributed to T J Lynch.

At least 37 records · Page 2Linked to original sources

A phase I study of gemcitabine and docetaxel in patients with metastatic solid tumors.

BACKGROUND: A Phase I study was initiated to determine the maximum tolerated dose of weekly gemcitabine combined with monthly, fixed-dose docetaxel. METHODS: Patients with metastatic solid tumors were treated with docetaxel, 60 mg/m(2), on Day 1 every 28 days. Gemcitabine was administered on Days 1, 8, and 15 and underwent dose adjustment in cohorts of 3-6 patients. At the maximum tolerated dose, 11 additional patients were enrolled. RESULTS: Twenty-six patients received 85 cycles of therapy. At the first dose level, the planned gemcitabine dose on Days 1, 8, and 15 was 800 mg/m(2). Two of the 6 patients treated at this dose level experienced dose-limiting toxicities (DLTs) requiring the reduction of gemcitabine to 600 mg/m(2) per dose and the administration of ciprofloxacin, 500 mg orally twice daily, on Days 8-18. At the second dose level the first 3 patients experienced no DLTs and the dose of gemcitabine was increased to 700 mg/m(2). Two of the 6 patients treated at the 700 mg/m(2) dose level experienced DLTs. Eleven additional patients were enrolled at the recommended Phase II dose of gemcitabine (600 mg/m(2)). At this dose level, Grade 3/4 (according the National Cancer Institute's common toxicity criteria) neutropenia and thrombocytopenia occurred in 12.5% and 2.1% of cycles, respectively. Grade 3 and 4 nonhematologic toxicities were uncommon. Three of seven evaluable patients with pancreatic carcinoma had evidence of significant antineoplastic activity (three partial responses). In addition, two complete responses (one patient with gastric carcinoma and one patient with ovarian carcinoma) and one partial response (patient with hepatocellular carcinoma) were noted in patients with other solid tumors. CONCLUSIONS: The regimen comprised of docetaxel, 60 mg/m(2), on Day 1 and gemcitabine, 600 mg/m(2), on Days 1, 8, and 15 with ciprofloxacin on Days 8-18 every 28 days is safe, well tolerated, and active.

Antimetabolites, Antineoplastic↗

A phase I clinical and pharmacokinetic study of the dolastatin analogue cemadotin administered as a 5-day continuous intravenous infusion.

PURPOSE: The dolastatins are a class of naturally occurring cytotoxic peptides which function by inhibiting microtubule assembly and tubulin polymerization. Cemadotin is a synthetic analogue of dolastatin 15 with potent antiproliferative and preclinical antitumor activity. This report describes a phase I study to evaluate the administration of cemadotin to adult cancer patients by a 5-day continuous intravenous (CIV) infusion. METHODS: All patients had histologically confirmed refractory solid tumors. The dose was escalated from an initial level of 2.5 mg/m2 (0.5 mg/m2 daily) according to a modified Fibonacci algorithm. A minimum of three patients was evaluated at each dose level until the maximum tolerated dose (MTD) was established. Treatment was repeated every 21 days until patients were removed from the study due to toxicity or disease progression. Drug-related toxicities were evaluated and graded by the U.S. National Cancer Institute's Common Toxicity Criteria. A radioimmunoassay (RIA) that detected both the parent drug and its metabolites with an intact N-terminal region of the molecule was used for pharmacokinetic studies. RESULTS: Twenty heavily pretreated patients received a total of 40 courses of cemadotin over five dose levels ranging from 2.5 to 17.5 mg/m2. Reversible dose-related neutropenia was the principal dose-limiting toxicity and 12.5 mg/m2 was established as the MTD. Nonhematologic toxicities attributed to the drug were moderate, and there was no evidence of the cardiovascular toxicity noted in the prior phase I studies of cemadotin given IV as a 5-min injection or 24-h infusion. There were no objective antitumor responses. Time courses of the cemadotin RIA equivalent concentration in whole blood were defined in 14 patients during the first cycle of therapy. The RIA-detectable species exhibited apparent first-order pharmacokinetics across the entire range of doses. The mean +/- SD of the observed steady-state blood concentration at the 12.5 mg/m2 MTD was 282 +/- 7 nM (n = 3). Blood levels decayed monoexponentially following the end of the infusion, with a mean half-life of 13.2 +/- 4.3 h (n = 14) in all patients. Mean values (n = 14) of the total blood clearance and apparent volume of distribution at steady state were 0.52 +/- 0.09 lh/m2 and 9.9 +/- 3.3 l/m2, respectively. CONCLUSIONS: The cardiotoxic effects of cemadotin were completely avoided by administering it as a 120-h CIV infusion. Thus. cardiovascular toxicity appears to be associated with the magnitude of the peak blood levels of the parent drug or its metabolites, whereas myelotoxicity is related to the duration of time that blood levels exceed a threshold concentration. Nevertheless, the data acquired during the extensive clinical experience with cemadotin requires careful examination to assess whether advancing this compound into disease-oriented efficacy studies is merited.

Adult↗

Biotechnology: alternatives to human plasma-derived therapeutic proteins.

Proteins derived from human plasma have become critically important therapeutic products since their introduction in the 1940s. In the last 20 years, the tools of molecular biology have provided alternatives to the administration of the natural products. Recombinant analogues of Factor VIII and Factor IX are commercially available, and recombinant forms of other plasma proteins are under development. Genetic engineering also provides the opportunity to modify a natural protein to improve the efficiency with which it can be produced in vitro, or to change its therapeutic profile. More efficient production systems, such as transgenic plants or animals, may yield less costly therapies and a wider availability of products that are now in limited supply. Finally, gene therapy offers the prospect of permanently correcting conditions arising from deficiencies in any one of several plasma proteins, freeing individuals from the need to undergo periodic treatments with exogenous proteins.

Biotechnology↗

Abscisic acid inhibition of radicle emergence but not seedling growth is suppressed by sugars.

Low concentrations of sugars altered the sensitivity of seed germination to inhibition by exogenous abscisic acid (ABA). Germination of wild-type and ABA-insensitive (abi) Arabidopsis seeds was assayed on media containing ABA and a variety of sugars and sugar alcohols. The inhibitory effects of ABA were strongly repressed in the presence of 15 to 90 mM glucose (Glc), sucrose, or fructose, but not by comparable concentrations of sorbitol or mannitol. Several features of the response to Glc are inconsistent with a purely nutritional effect: The optimal sugar concentration is low and differs between the wild type and the abi mutants. Furthermore, Glc suppression of ABA inhibition is light dependent and limited to the process of radicle emergence.

Abscisic Acid↗

Regulation and function of the Arabidopsis ABA-insensitive4 gene in seed and abscisic acid response signaling networks.

We have characterized developmental, environmental, and genetic regulation of abscisic acid-insensitive (ABI)4 gene expression in Arabidopsis. Although expressed most strongly in seeds, ABI4 transcripts are also present at low levels in vegetative tissue; vegetative expression is not induced by abscisic acid (ABA) or stress treatments. Comparison of transcript levels in mature seeds of ABA-insensitive, ABA-hypersensitive, ABA-deficient, or heterochronic mutants indicates that ABI4 expression is altered in only two of the backgrounds, the ABA-insensitive mutants abi1-1 and abi3-1. To determine whether ABI4 is necessary and/or sufficient for ABA response, we assayed the effects of loss of ABI4 function and ectopic ABI4 expression on growth and gene expression. We examined genetic interactions among three ABA response loci, ABI3, ABI4, and ABI5, by comparing phenotypes of mutants, ectopic expression lines, mutants carrying an ectopically expressed transgene, and the corresponding wild-type lines. Our results indicate some cross-regulation of expression among ABI3, ABI4, and ABI5 and suggest that they function in a combinatorial network, rather than a regulatory hierarchy, controlling seed development and ABA response.

Abscisic Acid↗

The Arabidopsis abscisic acid response gene ABI5 encodes a basic leucine zipper transcription factor.

The Arabidopsis abscisic acid (ABA)-insensitive abi5 mutants have pleiotropic defects in ABA response, including decreased sensitivity to ABA inhibition of germination and altered expression of some ABA-regulated genes. We isolated the ABI5 gene by using a positional cloning approach and found that it encodes a member of the basic leucine zipper transcription factor family. The previously characterized abi5-1 allele encodes a protein that lacks the DNA binding and dimerization domains required for ABI5 function. Analyses of ABI5 expression provide evidence for ABA regulation, cross-regulation by other ABI genes, and possibly autoregulation. Comparison of seed and ABA-inducible vegetative gene expression in wild-type and abi5-1 plants indicates that ABI5 regulates a subset of late embryogenesis-abundant genes during both developmental stages.

Abscisic Acid↗

Sedation for intractable distress of a dying patient: acute palliative care and the principle of double effect.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded the Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The Center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. The case presented is of a young man dying of recurrent epithelioid hemangioendothelioma, distressed with stridor and severe pain, whose poorly controlled symptoms were successfully treated with an infusion of propofol, titrated to provide effective comfort in the last few hours of the patient's life. The tenet of double effect, which allows aggressive treatment of suffering in spite of foreseeable but unintended consequences, is reviewed. The patient's parents were invited and contributed to the Rounds, providing compelling testimony to the power of the presence of clinicians at the time of death and the importance of open communication about difficult ethical issues.

Adult↗

Communicating genetic risk: pros, cons, and counsel.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a non-profit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. This case is of a woman with a personal, and a strong family history of breast cancer, who considered genetic testing for mutations in the BRCA1 and BRCA2 genes. The details of the case have been altered to protect the patient's anonymity. The patient was very anxious and there was disagreement between her healthcare providers about the potential benefits of genetic testing. The discussion of the case focused on several controversial issues, particularly the ownership of genetic information, and who is responsible for disseminating information to the family members at risk. The difficulties in communicating risk, providing emotional support and coping with the continuing uncertainties about screening and intervention are reviewed with an overview of the molecular biology, inheritance, and epidemiology of the BRCA1 and BRCA2 genes.

Adaptation, Psychological↗

Sexuality and cancer: conversation comfort zone.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. Psychosocial issues profoundly affect patients with cancer. Of the many complexities that make up the psychosocial dynamic, perhaps the medical profession is most uncomfortable with sexuality. Many elements of sexual behavior remain high-profile taboos. A number of diseases and treatments significantly affect sexual function. Male and female sexuality were discussed in two separate rounds with an emphasis on how to begin a dialogue about sexuality without jeopardizing other aspects of the relationship with patients. Three cases were presented. A patient with prostate cancer considering treatment options for early-stage disease and two patients with gynecologic malignancies; one with a colostomy following cytoreductive surgery for ovarian cancer and the other with a failed vaginal reconstruction for recurrent squamous cell carcinoma of the vagina. Staff discussed the wide diversity of response to sexual dysfunction and the difficulties that patients face. A sensitive and informed approach to discussing sexuality can provide effective support. The elements of successful dialogue are presented in the PLISSIT model.

Adult↗

Lung cancer highlights.

Have we made any progress in the treatment of advanced non-small cell lung cancer (NSCLC) over the past 15 years? After hearing the Eastern Cooperative Oncology Group (ECOG) 1594 presented by Dr. Joan Schiller at the plenary session of the 36th Annual Meeting of ASCO, it is hard to be certain. SCHILLER: reported the results of one of the world's largest randomized trials in metastatic lung cancer comparing four platinum-based doublets. There were no differences in survival (primary endpoint) or response between these four regimens, although the cisplatin/gemcitabine arm had a superior time to progression. In her commentary on this study, Dr. Francis Shepherd concluded that progress in the treatment of metastatic lung cancer has occurred at "a snail's pace." Despite the disappointing results of ECOG 1594, there were notable trials describing new agents with novel mechanisms of action reported at this year's ASCO meeting. In small-cell lung cancer, the combination of cisplatin/ irinotecan was found to be superior to cisplatin/etoposide. For NSCLC, novel agents Iressa anti-epidermal growth factor receptor tyrosine kinase and anti-vascular endothelial growth factor monoclonal antibody appear promising.

Antineoplastic Combined Chemotherapy Protocols↗

Burnout: caring for the caregivers.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. Burnout describes the end result of stress in the professional life of a physician or caregiver and combines emotional exhaustion, depersonalization and low personal accomplishment. This problem is common in health care workers in every specialty and may affect not only personal satisfaction, but also the quality of care delivered to patients. Burnout is particularly relevant in oncology where caregivers work closely with patients who have life-threatening illnesses and therapy often has only a limited impact. Burnout was discussed in the rounds with an emphasis on factors which precipitate or prevent stress among health care workers. Presentations were made by Dr. Canellos of the Dana Farber Cancer Institute, and Dr. Picard of the Institute for Health Professions. Staff discussed the main issues contributing to burnout including the health care system, lack of time and inadequate training. They considered preventative measures including psychological support of the health care team, communication and management skills, and effective coping mechanisms.

Adaptation, Psychological↗

A staff dialogue on aggressive palliative treatment demanded by a terminally ill patient: psychosocial issues faced by patients, their families, and caregivers.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum during which caregivers discuss a specific cancer patient, reflect on the important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from their fellow staff members. In this article, the case presentation and verbatim dialogue from the rounds are discussed with an emphasis on staff psychosocial issues. The case presented was of a 32-year-old man, who developed small cell osteosarcoma and was treated at MGH. He died after undergoing multiple courses of relatively ineffective chemotherapy. The case is made all the more poignant because of the pleasures, hopes and stresses of having a child late in the course of his illness. Staff identified closely, both with him and his family, and their concern for him brought joy and meaning to their work, yet this complicated their ability to deal with his impending death. They felt that his unwillingness to admit defeat prevented them from saying goodbye to someone whom they loved and admired. Despite this, staff recognized that, ultimately, the patient's emotional needs and wishes had to be respected as a first priority and that constructive closure can be worked toward, if not achieved. In such situations, it is vital to have a colleague support system and a forum for discussion of such issues in order to defuse distress and reassure staff that they are doing all that can be done as professionals and caregivers.

Adult↗

A staff dialogue on caring for a cancer patient who commits suicide: psychosocial issues faced by patients, their families, and caregivers.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a non-profit organization dedicated to supporting and advancing compassionate health care delivery which provides hope to the patient, support to caregivers, and encourages the healing process. The Center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum during which caregivers discuss a specific cancer patient, reflect on the important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from their fellow staff members. The case presented was of a 31-year-old man who developed adenocarcinoma of the lung with painful bone metastases. His tumor was unresponsive to treatment and he subsequently committed suicide by shooting himself. The verbatim and subsequent discussion raised a number of issues. Staff were devastated by the violent way that he ended his life. They questioned whether more could have been done to prevent this outcome, yet acknowledged that it mirrored the way he had lived, and were able to discuss the values by which we live and die. Some, but not all, felt that the patient had the right to choose how and when to end his life.

Adenocarcinoma↗

A staff dialogue on do not resuscitate orders: psychosocial issues faced by patients, their families, and caregivers.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a non-profit organization dedicated to supporting and advancing compassionate health care delivery which provides hope to the patient, support to caregivers, and encourages the healing process. The Center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. The following case of a woman who developed lymphoma was discussed at the July and August, 1997 Schwartz Center Rounds. There were considerable delays and uncertainties in the diagnosis, which was followed by an unpredictably chaotic clinical course. Although she had made it clear to her doctor that she did not want "heroic measures," she had unexpectedly rallied so many times that her son and her husband wanted her doctors to do everything possible to keep her alive, including the performance of cardiopulmonary resuscitation (CPR). The clinical benefit of CPR in the event of cardiac arrest in those with cancer is discussed, as are do not resuscitate (DNR) orders, living wills, and healthcare proxies. In addition, the issues that surround DNR status, including who should discuss DNR status with a patient, and how and when it should be discussed, are reviewed. Staff raised concerns about the effect of discussing DNR status on the doctor-patient relationship, and wondered whether writing DNR orders adversely affect the care of patients.

Advance Directives↗

Lung cancer highlights.

Explore the source record for details and available documents.

Antineoplastic Combined Chemotherapy Protocols↗

A staff dialogue on a socially distanced patient: psychosocial issues faced by patients, their families, and caregivers.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a non-profit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. The following case of an HIV-positive woman who was diagnosed with cervical cancer during a twin pregnancy was discussed at the May, 1999 Schwartz Center Rounds. The patient was in drug rehabilitation having been dependent on crack cocaine, with a past history of syphilis and gonorrhea. She was single and her other children were in foster care. Initially she was suspicious and non-compliant. A plan was negotiated to biopsy the cervical lesion after cesarean section and with confirmation of malignancy she underwent radical surgery and subsequently radiotherapy. Despite the almost insurmountable social and educational distance between her and her caregivers, they managed to bond and facilitate care. Although there were compromises with which staff were uncomfortable, the relationship was maintained and continues.

Adult↗

Reality testing in cancer treatment: the phase I trial of endostatin.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a non-profit organization dedicated to supporting and advancing compassionate health care delivery which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. The September 1999 Schwartz Center Rounds addressed the growing attention around the phase I trial of Endostatin. Endostatin represents a new treatment paradigm. It is an anti-angiogenic protein, an endogenous fragment of collagen XVIII. In an attempt to ensure a fair allocation of a very limited number of treatment slots in this classical phase I trial, a lottery was established. More than 1,400 patients enrolled within two days of the lottery, all vying for three places in the first cohort. Two contrasting cases are presented, each a potentially eligible patient. The discussion focuses on the dilemma presented by patients desperate for an unproven treatment and the responsibility of staff to explain and support without compounding the hype or suffocating the hope.

Adult↗