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M Bower

Publications and source records attributed to M Bower.

At least 91 records · Page 5Linked to original sources

Meeting review: the Second meeting on the Critical Assessment of Techniques for Protein Structure Prediction (CASP2), Asilomar, California, December 13-16, 1996.

In most fields of scientific endeavor, the outcomes of important experiments are not always known before the experiments are performed. But in protein structure prediction, algorithms are usually developed and tested in situations where the answers are known. In December 1996, the Second Meeting on the Critical Assessment of Techniques for Protein Structure Prediction (CASP2) was held in Asilomar, California to rectify this situation: protein sequences were provided in advance for which the experimental structure had not yet been published. Over 70 research groups provided bona fide predictions on 42 targets in four categories: comparative or 'homology' modeling, fold recognition or 'threading', ab initio structure predictions, and docking predictions. Since the previous CASP meeting in 1994, the role of fold recognition in structure prediction has increased enormously with the largest number of groups participating in this category. In this review, we highlight some of the important developments and give at least a qualitative sense of what kind of methods produced some of the better predictions.

Computer Simulation↗

Treatment of men with metastatic non-seminomatous germ cell tumours with cyclical POMB/ACE chemotherapy.

BACKGROUND: An alternating combination chemotherapy schedule for advanced nonseminomatous germ cell tumours (NSGCT) has been in use since 1977. PATIENTS AND METHODS: Three hundred thirty-nine men with metastatic NSGCT were treated with POMB/ACE (cisplatin, vincristine, methotrexate, bleomycin, actinomycin D, cyclophosphamide and etoposide), including 42 who had received previous chemotherapy or radiotherapy. Previously untreated patients were classified according to the International Germ Cell Cancer Collaborative Group (IGCCCG) model, and 31% were in the worst prognostic group. RESULTS: The median follow-up is eight years. The overall survival at five years is 82% (95% confidence interval (CI); 78%-85%). The survival of untreated patients exceeded that for previously treated patients (log-rank P = 0.04) and of testicular tumours exceeded that for primary extragonadal tumours (log-rank P < 0.0001). The survival of men with IGCCCG poor prognosis disease at three years is 75% (95% CI: 65%-84%) compared to 50% in the large cohort which was used to derive the model. There were five early treatment related deaths. In addition, five patients developed acute leukaemia, one developed a second primary lung adenocarcinoma, one man died of pulmonary fibrosis and three men died of cerebrovascular or cardiovascular disease. CONCLUSIONS: The POMB/ACE schedule has been employed in a large series of men with metastatic NSGCT over two decades. The fatal toxicity is equivalent to that described for simpler regimens. It yields equivalent response rates and survival in men with good prognosis disease and appears to achieve better survival in patients with poor prognosis disease.

Adolescent↗

FaFEC: a novel regimen for advanced ovarian cancer.

A palliative combination chemotherapy regimen (FaFEC) was developed for patients with relapsed epithelial ovarian cancer in particular patients relapsing after, or ineligible to enter, phase II trials, usually due to lack of evaluable disease. Forty-six patients were enrolled. Patients had received a mean of 2.3 previous drug regimens and nine (19%) had intestinal obstruction at the start of FaFEC. The majority of patients were inevaluable by WHO criteria so objective response data was obtained from serial serum CA125 evaluations. A serological response was demonstrated in 8/44 (18%). The responders included 6/27 women who had a prior relapse-free interval of less than 3 months, four who were resistant to platinum chemotherapy and three patients who had previously received paclitaxel. The major (WHO grade 3/4) toxicities included leucopenia (six patients), anemia (three patients), thrombocytopenia (two patients), nausea and vomiting (four patients) and severe infections (five patients). Following FaFEC the median time to failure was 0.48 years and the median survival was 0.66 years. FaFEC was effective in this group of very poor prognosis patients. The serological response rate of 18% is noteworthy considering the multiple prior treatments that patients had received and the short treatment free intervals. FaFEC may be useful second line therapy in epithelial ovarian cancer patients ineligible for phase II studies and should be considered for a randomized comparison with paclitaxel.

Journal Article↗

Surveillance policy for stage I ovarian germ cell tumors.

PURPOSE: Surveillance for stage I male germ cell tumors (GCT) is well established as a standard practice; however, such a policy has not been evaluated for women with equivalent tumors. This study was designed to evaluate the management of grade II or higher stage Ia tumors by close surveillance to minimize treatment, while reserving chemotherapy for patients with residual or recurrent disease. PATIENTS AND METHODS: Between 1973 and 1995, 24 patients with malignant stage Ia ovarian GCT were enrolled onto a surveillance program. The group consisted of nine patients with dysgerminoma, nine with pure immature teratoma, and six with endodermal sinus tumor (with or without immature teratoma). Treatment consisted of surgical resection without adjuvant chemotherapy, followed by a surveillance program of clinical, serologic, and radiologic review, and included a second-look procedure for patients enrolled after 1982. RESULTS: All but one patient are alive and in remission after a median follow-up of 6.8 years. The 5-year overall survival is 95%, and the 5-year disease-free survival is 68%. Eight patients have required chemotherapy for recurrent disease or second primary ovarian GCT. This includes three patients with grade II immature teratoma and three patients with dysgerminoma, and a further two women with dysgerminoma who developed contralateral (presumed second primary) dysgerminoma 4.5 and 5.2 years after their first tumor. All but one, who died of a pulmonary embolus, have been successfully salvaged with chemotherapy. CONCLUSION: Our experience emphasizes that patients with true stage Ia ovarian GCT are adequately managed by surgical resection followed by careful clinical, radiologic, and serologic surveillance. These patients do not require adjuvant chemotherapy or radiotherapy, thus avoiding the potential complications of secondary leukemia and infertility.

Antineoplastic Agents↗

EMA/CO for high-risk gestational trophoblastic tumors: results from a cohort of 272 patients.

PURPOSE: To evaluate the results of etoposide, methotrexate, and dactinomycin alternating with cyclophosphamide and vincristine (EMA/CO) chemotherapy in women with high-risk gestational trophoblastic tumors (GTT) and to document the middle- and long-term toxicity of the regimen. PATIENTS AND METHODS: A total of 272 consecutive women with high-risk GTT, including 121 previously treated patients, were treated with weekly EMA/CO. The median follow-up duration is 4.5 years (range, 1 to 16). RESULTS: The cumulative 5-year survival rate is 86.2% (95% confidence interval, 81.9% to 90.5%). No deaths from GTT have occurred later than 2 years after the end [corrected] of EMA/CO. In a multivariate model, adverse prognostic factors were the presence of liver metastases (P < .0001), interval from antecedent pregnancy (P < .0001), brain metastases (P = .0008), and term delivery of antecedent pregnancy (P = .045). There were 11 (4%) early deaths, while 213 patients (78%) achieved a complete remission. Forty-seven (17%) developed drug resistance to EMA/CO, of whom 33 (70%) were salvaged by further cisplatin-based chemotherapy and surgery. Two women developed acute myeloid leukemia, two cervical malignancy, and one gastric adenocarcinoma after EMA/CO. More than half (56%) of the women who had fertility-conserving surgery and who have been in remission at least 2 years have become pregnant since the completion of EMA/CO, with 112 live births, including three infants with congenital abnormalities. CONCLUSION: EMA/CO is an effective and well-tolerated regimen for high-risk GTT. More than half of the women will retain their fertility; however, there is a small but significant risk of second malignancy.

Adolescent↗

Phase II trial of 13-cis-retinoic acid for poor risk HIV-associated Kaposi's sarcoma.

Fifteen men with HIV-associated Kaposi's sarcoma (KS) and poor risk disease according to the TIS staging were enrolled in a phase II trial of oral 13-cis-retinoic acid. The median CD4 cell count was 95 cells/microl (range 7-260) and 6 had prior AIDS-defining opportunistic infections. One patient was withdrawn on account of cutaneous toxicity. Evaluation was by AIDS Clinical Trials Group (ACTG)1 defined assessment. One patient achieved a partial response and remains on treatment in partial remission. Thus the overall response rate is 7% (95% confidence interval 0-23%). A further 5 patients had stable disease (38%: 95% confidence interval 7-64%). The overall low activity, considerable toxicity and limited cosmetic benefit even in responding patients limits the value of this approach in KS. However, this treatment strategy may be more rewarding in early good risk KS.

AIDS-Related Opportunistic Infections↗

A weekly alternating chemotherapy regimen with low toxicity for the treatment of aggressive lymphoma.

A total of 50 consecutive adult patients with newly diagnosed aggressive non-Hodgkin's lymphoma were treated with a weekly alternating combination chemotherapy schedule, BEMOP/CA, including bleomycin, etoposide, methotrexate, vincristine, cyclophosphamide and Adriamycin. Two-thirds of the patients were over 60 years old or had stage 4 disease. Clinical remission was achieved in 56% of cases. The 3-year survival is 53% (95% confidence interval, 39-66%). The presence of B symptoms and a serum albumin value of <33 g/l at presentation were poor prognostic indicators for survival in a multivariate proportional-hazards model. Overall, the response rate and survival for this group of patients with intermediate- and high-grade lymphomas is similar to results previously reported. The BEMOP/CA treatment was brief (16 weeks) and associated with a low fatal toxicity (one early death and one late fatality from Pneumocystis pneumonia), and the drug costs are equivalent to those for eight cycles of CHOP.

Adolescent↗

Chemotherapy for ovarian germ cell tumours.

59 patients were treated for newly diagnosed metastatic ovarian germ cell tumours with POMB/ACE chemotherapy (which contains cisplatinum, vincristine, methotrexate, bleomycin, actinomycin D, cyclophosphamide and etoposide). The median follow-up was 7.7 years. The 3 year survival is 87.8% (95% confidence interval 76.9-93.9%) and no relapses occurred more than 3 years after treatment. 4 (7%) patients had primary drug resistance to POMB/ACE and 4 (7%) have relapsed. One patient in complete remission developed secondary acute myeloid leukaemia after receiving a total of 1.3 g/m2 etoposide. 6 of 12 (50%) patients referred at relapse were salvaged by POMB/ACE. 14 of 33 (42%) women (> 18 years old) have had successful pregnancies after fertility conserving surgery and chemotherapy with no congenital abnormalities reported. The POMB/ACE regimen is as efficacious as other published regimens for ovarian germ cell tumours (OGCT) and balances a low incidence of life-threatening toxicity with a high success rate.

Adolescent↗

Medullary thyroid cancer: the role of radiotherapy in local control.

Fifty-one patients were treated with radiotherapy for loco-regional medullary thyroid cancer between 1960-1992. The actuarial overall survival at 5, 10 and 20 years was 69%, 52% and 30%, respectively. Patients were classified according to clinical stage (node-positive or -negative), post-operative histological residual disease status (none, microscopic or macroscopic) and dose of radiotherapy received. By univariate analysis, loco-regional recurrence-free survival was significantly longer for node-negative patients (P = 0.03). Patients who received at least 60 Gy over 6 weeks showed a trend towards improved local control (P = 0.23). The only significant variable by multivariate analysis for local recurrence-free survival was post-operative residual disease status (P=0.0005). The local control rate at 5 years was 100% for patients with no residual disease, 65% for those with microscopic tumour, and 24% for those with macroscopic residual disease. We conclude that there is a valuable role for radiotherapy in the management of patients with residual microscopic or macroscopic disease following surgery, as well as in those with inoperable disease.

Actuarial Analysis↗

The Charing Cross Hospital experience with temozolomide in patients with gliomas.

Temozolomide, a new oral cytotoxic agent, was given to 75 patients with malignant gliomas. The schedule used was for the first course 150 mg/m2 per day for 5 days (i.e. total dose 750 mg/m2), escalating, if no significant myelosuppression was noted on day 22, to 200 mg/m2 per day for 5 days (i.e. total dose 1000 mg/m2) for subsequent courses at 4-week intervals. There were 27 patients with primary disease treated with two courses of temozolomide prior to their radiotherapy and 8 (30%) fulfilled the criteria for an objective response. There were 48 patients whose disease recurred after their initial surgery and radiotherapy and 12 (25%) fulfilled the criteria for an objective response. This gave an overall objective response rate of 20 (27%) out of 75 patients. Temozolomide was generally well tolerated, with little subjective toxicity and predictable myelosuppression. However, the responses induced with this schedule were of short duration and had relatively little impact on overall survival. In conclusion, temozolomide given in this schedule has activity against high grade glioma. However, studies evaluating chemotherapy in primary brain tumours should include a quality-of-life/performance status evaluation in addition to CT or MRI scanning assessment.

Adult↗

Randomized cross-over comparison of liposomal daunorubicin versus observation for early Kaposi's sarcoma.

OBJECTIVES: To evaluate single-agent liposomal daunorubicin chemotherapy in the management of early HIV-related Kaposi's sarcoma (KS). DESIGN: Randomized cross-over comparison of liposomal daunorubicin versus observation. SETTING: Study conducted at single site in tertiary referral HIV unit. PATIENTS: Twenty-nine HIV-seropositive men with < 20 cutaneous KS, no visceral involvement and CD4 cell counts < 400 x 10(6)/I were randomized. Adequate haematological, hepatic and renal function was required for entry. A left ventricular ejection fraction of > 45% was necessary for eligibility. INTERVENTIONS: Patients were randomized to 12 weeks observation or 12 weeks of liposomal daunorubicin 40 mg/m2 every 2 weeks. After 12 weeks, or at disease progression, patients were crossed over to receive the alternative arm. MAIN OUTCOME MEASURES: Disease evaluation was according to AIDS Clinical Trials Group criteria for response assessment and toxicity was recorded using the World Health Organization standardized grading. RESULTS: Response rate to initial liposomal daunorubicin was six out of 15 (40%) and none experienced a spontaneous response during the observation arm. Six patients (40%) randomized to the initial chemotherapy arm progressed during chemotherapy, while 10(72%) in the observation arm progressed. Neutropenia was the main toxicity associated with liposomal daunorubicin and was documented following 20 out of 139(14%) treatment cycles. CONCLUSIONS: Liposomal daunorubicin is a well tolerated and efficacious treatment for early KS; however, the duration of response is brief.

AIDS-Related Opportunistic Infections↗

Placental site trophoblastic tumor: molecular analysis and clinical experience.

Placental site trophoblastic tumor is a very rare variant of gestational trophoblastic disease which differs histologically and immunocytochemically from gestational choriocarcinoma. The English language literature includes only 74 reported cases. Seventeen patients have been managed at Charing Cross Hospital with this diagnosis. The median follow-up is 4.6 years, and the 5-year overall survival is 80% (95% confidence interval, 55-93%). Multivariate regression analysis identified an interval of >2 years since the preceding pregnancy as an independent adverse prognostic factor. Genotypic analysis by PCR allelotyping has confirmed the gestational origin of all 11 tumors successfully studied. More detailed molecular analysis has identified the causative pregnancy for eight tumors. Five were diploid biparental tumors following term pregnancies, and three were androgenetic tumors following monospermic complete hydatidiform moles.

Adult↗