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Biomedical subjects

S B Kaye

Publications and source records attributed to S B Kaye.

At least 109 records · Page 6Linked to original sources
PubMed1997

The establishment of a xerostomia clinic: a prospective study.

The study investigated the aetiological factors and management of patients who have xerostomia. The subjects were 100 consecutive patients referred to the Oral Medicine Unit for investigation of oral dryness. A detailed case history was recorded and patients underwent a systematic examination together with sialometry, haematological, biochemical and immunological investigations. Suspected cases of Sjögren's syndrome (SS) were referred for assessment by a rheumatologist and ophthalmologist. Objective evidence of salivary gland hypofunction was found in 39 patients. A definite diagnosis of primary and secondary SS was made in 24 and 15 patients respectively, a further five cases had possible primary SS. Other causes of xerostomia were: undiagnosed diabetes (3); drug-induced (11); therapeutic radiation (3); alcohol-related (3); psychogenic (15) and idiopathic (21). Patients complaining of a dry mouth should be questioned about non-oral symptoms. In total, 40% of patients attending the dry mouth clinic had a diagnosis of SS.

Adult↗
PubMed1997

Association between total astigmatism and myopia.

PURPOSE: To determine whether there is an association between degree of myopia and total astigmatism. SETTING: St. Paul's Eye Unit, Royal Liverpool University Hospitals, Liverpool, United Kingdom. METHODS: Refractive and keratometric data for 105 eyes of 105 patients with myopia and astigmatism who attended a photorefractive keratectomy (PRK) assessment clinic were analyzed. The refractive data of the patients having PRK were also analyzed before and after treatment. RESULTS: There was a strong correlation between total astigmatism (A) and degree of myopia. This could be represented by a linear regression line in the form A = -0.13 x myopia + 0.86 (at the corneal plane). Although there were trends, there was no significant correlation between the degree of corneal (keratometric) astigmatism and myopia. Data of 35 patients who had PRK were analyzed to determine whether the observed effect on astigmatism could have been predicted from the relationship between myopia and astigmatism. Forty-nine percent of patients with myopia and astigmatism were overcorrected by 0.6 diopter (D) (0.2 to 2.0 D), resulting in a preoperative to postoperative axis shift of 73 degrees; 40% were undercorrected by 1.2 D (0.5 to 3.1 D). Both over- and undercorrections could have been predicted from the relationship between myopia and astigmatism. CONCLUSIONS: The total amount of astigmatism in the myopic eye is proportional to the degree of myopia. The amount that one intends to treat should, therefore, be modified according to the amount of myopia to be treated, as determined by the relationship between the degree of astigmatism and myopia.

Adult↗
PubMed1997

Prognostic factors for patients with advanced seminoma treated with platinum-based chemotherapy.

Prognostic factors for 3-year progression-free survival (PFS) were defined in 286 patients with advanced seminoma treated with cisplatin-based chemotherapy at 10 European oncology units (no prior treatment: 236; prior radiotherapy: 50). Previously irradiated patients displayed a 69% PFS as compared to 87% in those presenting with advanced seminoma at the time of diagnosis (P = 0.009). In the univariate analysis, the extent and site of disease before chemotherapy and the level of serum LDH (< 2.0 versus > or = 2.0 x upper limit of normal) correlated with PFS in previously non-irradiated patients, but not in patients with prior radiotherapy. The multivariate analysis was, therefore, restricted to previously non-irradiated patients. The presence of non-pulmonary visceral metastases and a serum LDH level of > or = 2 x normal (N) proved to be independent prognostic factors. Based on these variables, two prognostic models were constructed and validated in an external data set of 166 comparable patients. For clinical use, Model 2 is recommended. The good-prognosis group comprises non-irradiated patients with stage II seminoma and any LDH level at presentation, or stage III and IV patients (with lung metastases only) whose serum LDH level is < 2 x N. These patients display a 94% 3-year PFS. The poor prognosis group includes all other patients with a 56% PFS. With this prognostic model, individualisation of the therapeutic approach may be considered in patients with advanced seminoma and a high risk of chemotherapy-related toxicity.

Adult↗
PubMed1997

Radiotherapy after chemotherapy for metastatic seminoma--a diminishing role. MRC Testicular Tumour Working Party.

In a retrospective study, data from 302 patients with metastatic testicular seminoma treated with chemotherapy between 1978 and 1990 in 10 European centres were analysed to evaluate the role, if any, of postchemotherapy treatment with irradiation. The primary endpoint of this study was the progression-free survival rate after chemotherapy with or without additional radiotherapy. This was related to the type of primary chemotherapy, sites and sizes of pre- and postchemotherapy masses, the extent of surgical resection after chemotherapy and the use of radiotherapy. 174 patients had residual disease at the end of chemotherapy. The most important prognostic factors for progression were the presence of any visceral metastases or raised LDH prechemotherapy, and the presence of residual disease at visceral sites after chemotherapy. Approximately half the patients with residual masses underwent postchemotherapy radiotherapy, with selection based predominantly on institutional practice. In patients receiving platinum-based chemotherapy, no significant difference was detected in progression-free survival whether or not radiotherapy was employed. Patients receiving BEP (bleomycin, etoposide and cisplatin) had a progression-free survival rate of 88% (95% CI, 80-96%) uninfluenced by postchemotherapy radiotherapy. In patients with residual masses confined to the abdomen after platinum-based chemotherapy, the absolute benefit to radiotherapy was estimated to be 2.3%. The potential benefit of postchemotherapy radiotherapy is minimal, and so it is concluded that the use of adjuvant radiotherapy to residual masses after platinum-based chemotherapy for metastatic seminoma is unnecessary.

Abdominal Neoplasms↗
PubMed1997

Phase II trials of docetaxel (Taxotere) in advanced ovarian cancer--an updated overview.

Docetaxel (Taxotere) has been studied at a dose of 100 mg/m2 i.v. as a one hour infusion every 3 weeks, in four phase II trials in patients with extensively pretreated ovarian cancer. A total of 340 patients were treated, including 256 patients in two separate EORTC (European Organization for Research and Treatment of Cancer) trials and 84 patients in two trials in the U.S.A. All patients had received prior cisplatin or carboplatin therapy and the treatment-free interval was less than 4 months in 155 patients. The overall response rate using conventional UICC criteria was 30% among 315 evaluable cases (95% confidence interval: 24-36%). Among 155 patients whose disease was most refractory (i.e. treatment-free interval was less than 4 months), the overall response rate was 28% (95% confidence interval: 19-36%). Response duration ranged from 4 to 17 months. Grade IV neutropenia was a common finding and fluid retention was observed. The incidence of febrile neutropenia ranged from 8 to 44% of patients with two deaths (i.e. 0.6% of the total treated) related to neutropenic sepsis. Docetaxel and paclitaxel (Taxol) have comparable activities in ovarian cancer. Ongoing studies with docetaxel include its use in patients as part of first-line therapy, as well as in patients refractory to paclitaxel. To prevent the development of fluid retention, these now involve the routine use of steroid prophylaxis. It is expected that docetaxel will prove to be an important addition to the drugs available for the treatment of ovarian cancer.

Adult↗
PubMed1997

Tumour marker concentration at the start of chemotherapy is a stronger predictor of treatment failure than marker half-life: a study in patients with disseminated non-seminomatous testicular cancer.

We investigated the prognostic value of the serum half-life of human chorionic gonadotrophin (HCG) and alpha-fetoprotein (AFP) during induction chemotherapy and the relative prognostic importance of initial marker concentrations and marker half-life. Marker half-lives were calculated using two abnormal values observed between day 8 and day 22 of the first chemotherapy cycle. Moreover, analyses were carried out using day 43 as the second measurement point. Treatment failure at any time was chosen as the end point. The relative prognostic influence of marker half-lives and initial marker concentrations was tested in univariate and multivariate analyses. Half-lives were considered to be prolonged if > 3 days for HCG and > 6 days for AFP. In addition, we separated patients into those with half-lives > 6 days for HCG and those with half-lives > 10 days for AFP to examine whether these long half-lives were associated with a poor prognosis. A group of 669 patients treated with cisplatin combination chemotherapy was studied. Forty-two per cent of the patients had normal HCG and 37% had normal AFP at the start of chemotherapy. At day 22, HCG was still elevated in 138 patients and AFP in 211. At day 43, the numbers of these patients were 35 and 80 respectively. Based on the measurements obtained on day 8 and day 22, a half-life of HCG > 3 days or > 6 days and/or a half-life AFP > 6 days or > 10 days did not accurately predict treatment failure (P=0.413 and P=0.851, respectively; values obtained using tests for trend). However, initial marker concentrations of HCG and/or AFP > 1000 IU l(-1) were highly significant prognosticators for treatment failure (P=0.001 and P < 0.001 respectively), independent of half-life values. Half-lives calculated with the values obtained on day 43 did not contribute to the accuracy of the prediction of treatment failure. We conclude that half-lives of HCG and AFP during induction chemotherapy are inaccurate parameters for the prediction of treatment failure. In contrast, initial serum concentrations of HCG and AFP are highly significant in the prediction of unfavourable treatment outcome.

Analysis of Variance↗
PubMed1997

Protein kinase C: a worthwhile target for anticancer drugs?

Protein kinase C (PKC) is an enzyme family with serine/threonine kinase function which is involved in the transduction of signals for cell proliferation and differentiation. The important role played in processes relevant to neoplastic transformation, carcinogenesis and tumor cell invasion renders PKC a potentially suitable target for anticancer therapy. Bryostatin 1, a macrocyclic lactone isolated from Bugula nerutina, is a partial PKC agonist, and has shown potent antineoplastic properties in vitro and in vivo. Staurosporine, an alkaloid isolated from microbial sources, is ine of the most potent PKC inhibitors and has shown high antiproliferative activity in vitro, but poor selectivity. Staurosporine analogs have thus been synthesize with the aim of obtaining more selective PKC inhibition; among these, CGP 41251 has shown reduced PKC inhibitory activity, but a higher degree of selectivity when assayed for inhibition of different kinases. Several studies indicate a role for PKC in the regulation of the multidrug resistance (MDR) phenotype, since several PKC inhibitors are able to partially reverse MDR and inhibit P-glycoprotein (Pgp) phosphorylation. The MDR phenotype is also associated with variation in PKC isoenzyme content, in particular with PKC-alpha overexpression. While adequate PKC modulation might offer an attractive concept to modulate MDR, other potential mechanisms of PKC interaction with anticancer drugs exist and have been documented, such as the enhancement of chemotherapy-induced apoptosis by safingol, a specific PKC inhibitor. Three phase I clinical trials with bryostatin have been completed so far and have shown that myalgia is the dose-limiting toxicity, while some antitumor activity is evident. Safingol is presently undergoing a phase I clinical trial in combination with doxorubicin. While no definitive data are presently available, it appears that safingol plasma levels approach those associated with chemopotentiation in animals and no pharmacokinetic interaction between the two drugs exists. Drugs targeting PKC are well work considering for clinical trials, particularly for their potential as modulators of currently available cytotoxic agents.

Animals↗
PubMed1997

Signs and symptoms in patients with salivary gland hypofunction.

Salivary gland hypofunction can have a devastating effect on oral health and may be an indicator of systemic disease such as Sjögren's syndrome. This prospective study investigates the oral and non-oral signs and symptoms in 120 patients with objective evidence of salivary gland hypofunction (ie, an unstimulated whole salivary flow of < 0.2 ml/min). Patients were questioned about symptoms associated with decreased oral function; non-oral symptoms were also noted. The underlying cause of salivary gland hypofunction was established on the basis of clinical and laboratory findings and further investigations. Eighty-five per cent of patients reported symptoms of decreased oral function in addition to oral dryness. Non-oral signs and symptoms were reported by 106 patients. Fifty-three per cent of patients were diagnosed as having Sjögren's syndrome. The prevalence of the following non-oral signs and symptoms were significantly higher in patients with Sjögren's syndrome, than in those without; a history of dry/irritated eyes, salivary gland swelling, dry skin and reduced lacrimal flow. Salivary gland hypofunction is associated with a wide range of oral and non-oral signs and symptoms. Several of these are of potential value as triggers for the clinician to identify patients with Sjögren's syndrome, and should serve to prompt referral for specialist investigation.

Adult↗
PubMed1997

Importance of bleomycin in combination chemotherapy for good-prognosis testicular nonseminoma: a randomized study of the European Organization for Research and Treatment of Cancer Genitourinary Tract Cancer Cooperative Group.

PURPOSE: This prospective randomized trial was designed to compare the efficacy of etoposide plus cisplatin (EP) versus bleomycin, etoposide, and cisplatin (BEP) chemotherapy in patients with good-prognosis metastatic nonseminomatous testicular cancer. PATIENTS AND METHODS: Four hundred nineteen patients with good-prognosis nonseminomatous testicular cancer were randomized to receive four cycles of cisplatin 20 mg/m2 on days 1 to 5 plus etoposide 120 mg/m2 on days 1, 3, and 5 with or without bleomycin 30 mg weekly. RESULTS: Of 395 eligible patients, 169 of 195 patients allocated to EP (87%) and 189 of 200 patients allocated to BEP (95%) achieved a complete response with chemotherapy alone or after postchemotherapy surgery. These results are significantly different (P = .0075). After a median follow-up duration of 7.3 years, eight patients (4%) on each treatment arm relapsed. In view of the low number of unfavorable treatment outcomes (11%), no significant differences were detected in time to progression (P = .136) and survival (P = .262). Both the acute and late pulmonary toxicity and neurotoxicity were significantly greater in patients who received BEP, whereas Raynaud's phenomenon occurred exclusively in patients who received BEP (P < .001). Two patients treated with BEP died of bleomycin pulmonary toxicity. CONCLUSION: BEP is the most effective combination regimen in the treatment of disseminated nonseminomatous germ cell cancer. In this particular BEP regimen with etoposide at a dose of 360 mg/m2 per cycle, even in good-prognosis patients, bleomycin cannot be deleted without compromising treatment efficacy, but its use is associated with more toxicity (particularly pulmonary) and efforts to reduce this merit further exploration.

Adolescent↗
PubMed1997

Randomized trial of bleomycin, etoposide, and cisplatin compared with bleomycin, etoposide, and carboplatin in good-prognosis metastatic nonseminomatous germ cell cancer: a Multiinstitutional Medical Research Council/European Organization for Research and Treatment of Cancer Trial.

PURPOSE: This prospective randomized multicenter trial was designed to evaluate the efficacy of carboplatin plus etoposide and bleomycin (CEB) versus cisplatin plus etoposide and bleomycin (BEP) in first-line chemotherapy of patients with good-risk nonseminomatous germ cell tumors. PATIENTS AND METHODS: Between September 1989 and May 1993, a total of 598 patients with good-risk nonseminomatous germ cell tumors were randomized to receive four cycles of either BEP or CEB. In each cycle, the etoposide dose was 120 mg/m2 on days 1, 2, and 3, and the bleomycin dose was 30 U on day 2. BEP patients received cisplatin at 20 mg/m2/d on days 1 to 5 or 50 mg/m2 on days 1 and 2. For CEB patients, the carboplatin dose was calculated from the glomerular filtration rate to achieve a serum concentration x time of 5 mg/mL x minutes. Chemotherapy was recycled at 21-day intervals to a total of four cycles. RESULTS: Of patients assessable for response, 253 of 268 (94.4%) of those allocated to receive BEP achieved a complete response, compared with 227 of 260 (87.3%) allocated to receive CEB (P = .009). There were 30 treatment failures in the 300 patients allocated to BEP and 79 in the 298 allocated to CEB (log-rank chi 2 = 26.9; P < .001), which led to failure-free rates at 1 year of 91% (95% confidence interval [CI], 88% to 94%) and 77% (95% CI, 72% to 82%), respectively. There were 10 deaths in patients allocated to BEP and 27 in patients allocated to CEB (log-rank chi 2 = 8.77; P = .003), which led to 3-year survival rates of 97% (95% CI, 95% to 99%) and 90% (95% CI, 86% to 94%), respectively. CONCLUSION: With these drug doses and schedules, combination chemotherapy based on carboplatin was inferior to that based on cisplatin. This BEP regimen that contains moderate doses of etoposide and bleomycin is effective in the treatment of patients with good-prognosis metastatic nonseminoma.

Adult↗
PubMed1997

Histopathology and molecular cytogenetics of a corneal opacity associated with the trisomy 8 mosaic syndrome (46,XY/47,XY, +8).

The trisomy 8 mosaic syndrome (Tr8MS), karyotype 46,XY/47,XY, +8, is a rare multisystem disorder that may be associated with corneal opacity. We report the case of a dysmorphic infant with multiple congenital abnormalities referred to our unit with a congenital corneal opacity. Subsequent chromosomal analysis of peripheral leucocytes demonstrated constitutional Tr8MS. At 4 years of age, lamellar keratoplasty was performed. Histological examination confirmed the lesion to be consistent with a corneal choristoma. Cytogenetic studies using in situ hybridisation techniques showed the presence of trisomic cells in cell culture derived from the tissue in higher proportion (92%) than in the blood (44%). Amplification of the c-myc oncogene on chromosome-8 could not be detected in cells cultured from the corneal lesion. Although not proof, these findings lend support to the concept of the corneal lesion representing a focus of viable trisomic cells rather than an inflammatory response to a nidus of effete cells.

Abnormalities, Multiple↗
PubMed1997

Atraumatic transfer of the donor corneal button.

PURPOSE: To devise a method for atraumatic transfer of the donor corneal button by using a corneal shovel. METHOD: The donor cornea is lifted with a microcorneal shovel, and the epithelial surface dried with a microsponge applied to the corneal shovel to create a seal. This allows the shovel to be rotated through 180 degrees over the host eye with no movement of the donor cornea. The seal is then broken by applying a drop(s) of fluid onto the epithelial surface of the donor cornea or by touching the edge of the donor cornea to the edge of the host cornea. The donor cornea then slides or is floated onto the host eye. RESULTS: This technique has been performed on 52 corneal transplants with no complications such as slippage or falling off of the donor corneal button during transfer. CONCLUSION: This method provides a useful atraumatic surgical procedure for stabilising and transferring the donor cornea during corneal transplantation.

Cornea↗
PubMed1997

Phase I and pharmacokinetic study of tirapazamine (SR 4233) administered every three weeks.

Tirapazamine (SR 4233; 3-amino-1,2,4-benzotriazine-1,4-di-N-oxide) is a bioreductive agent exhibiting up to 200 x greater toxicity for hypoxic cells as compared to oxygenated cells. In murine studies, a selective increase in tumor kill was observed when tirapazamine was coadministered with other agents, notably cisplatin. A Phase I study of single-agent tirapazamine administered i.v. every 3 weeks was conducted to determine the toxicity of a schedule for use with systemic chemotherapy. A total of 28 patients were given 50 courses of tirapazamine at doses ranging from 36-450 mg/m2. No tumor responses were observed. Reversible deafness and tinnitus were dose-limiting, with ototoxicity observed in 1 of 6 patients treated at 330 mg/m2, 1 of 4 patients treated at 390 mg/m2, and 3 of 3 patients treated at 450 mg/m2. Muscle cramps, nausea, and vomiting were also observed. Pharmacokinetic studies revealed a greater than dose-proportional increase in the area under the plasma concentration x time curve (AUCs) of the two major metabolites. Patients who developed ototoxicity generally showed higher plasma AUC values for the parent drug and metabolites. The mean plasma tirapazamine AUC at 330 mg/m2 was 1026.5 microgram/ml x min (range 863. 8-1252.3), but no pharmacokinetic data are available for the solitary patient who developed otoxicity at this dose level. These AUC values were in the (estimated) range required for therapeutic effect in murine studies. Ototoxicity was not observed when the AUC of tirapazamine was equal to or less than 1252 microgram/ml x min. The dose of 330 mg/m2 was therefore chosen as an appropriate level for combination chemotherapy studies.

Adult↗
PubMed1996

Successful thrombolysis of SVC thrombosis associated with Hickman lines and continuous infusion chemotherapy.

In a pilot study of continuous infusion 5-fluorouracil and intermittent bolus doxorubicin and cyclophosphamide in women with breast cancer, four of 24 patients developed symptomatic superior vena cava or innominate vein thrombosis associated with the Hickman line, despite prophylactic treatment with very low dose warfarin (1-3 mg/day). In all four patients, local thrombolysis with streptokinase was successful and chemotherapy was continued through the Hickman line under anticoagulant cover, maintaining an international normalized ratio of 2.0-3.0. No patient developed recurrent thrombosis. Prophylactic anticoagulation should be considered in patients receiving continuous infusion chemotherapy through Hickman lines, as they are at risk of proximal vein thrombosis. A randomized study is needed to address the question of the optimum anticoagulant regimen to prevent such thromboses.

Adult↗
PubMed1996

Phase II clinical trials with rhizoxin in breast cancer and melanoma. The EORTC Early Clinical Trials Group.

Rhizoxin is a new anti-tumour agent isolated from the pathogenic fungus Rhizopus chinensis. It has shown broad activity against murine tumour models and is also active against vinca alkaloid-resistant cells. The purpose of our studies was to determine the clinical activity of this compound in patients with advanced breast cancer and melanoma. Based on the results of a phase I study, 2.0 mg m-2 was administered as intravenous infusion over 5 min every 21 days. Nineteen patients were entered into the breast cancer phase II trial and received a total of 50 courses (median 2, range 1-6). Of these, dose reductions were performed in three courses because of leucopenia or stomatitis (1.5 mg m-2, one course; 1.45 mg m-2, two courses). Twenty-six patients were entered into the melanoma trial and received a total of 70 courses (median 2, range 1-12). No dose reductions were required. All patients were eligible for toxicity. Haematological toxicity included neutropenia CTC grade 3 (29/120 courses, 24.2%) and grade 4 (11/20 courses, 9.2%). Only drug-related CTC grade 1 thrombocytopenia was observed. Non-haematological toxicity included alopecia in all patients after two courses of treatment as well as CTC grade 3/4 stomatitis and asthenia. In the breast cancer study, one patient achieved a more than 50% tumour reduction after six cycles but was progressing after 6 weeks. Another patient showed a partial remission after the first course but was taken off the study because of CTC grade 3 skin toxicity. One patient was not evaluable for response (early death). No objective remissions were observed in 15 evaluable patients. In melanoma, no objective remissions were observed. We conclude that rhizoxin can be safely administered at 2.0 mg m-2 every 3 weeks. However, it has little activity in patients with advanced breast cancer and melanoma.

Adult↗
PubMed1996

Retroperitoneal surgery: its wider role in the management of malignant teratoma.

OBJECTIVE: To review the results of the use of laparotomy to excise retroperitoneal metastases in patients with malignant teratoma of the testis. PATIENTS AND METHODS: The results of surgery for retroperitoneal teratoma metastases in 37 patients during the 5-year period from 1988 to 1993 were reviewed. Information on sexual dysfunction was obtained using a postal questionnaire. RESULTS: Patients were divided into three groups: the first comprised 28 patients who underwent elective surgery (excision of residual disease) after platinum and bleomycin-based chemotherapy. The second group comprised four patients who underwent interventional surgery to excise disease not responding to treatment, after which they completed chemotherapy. The third group comprised five patients who underwent surgery for relapsed disease; two had suffered an early and three a late relapse. Overall, 34 patients are alive, four are considered to have residual disease and two have recently undergone re-operation. CONCLUSIONS: In addition to removing residual disease after primary chemotherapy, surgery has a wider role in the management of metastatic teratoma. Carefully timed interventional surgery for disease not responding to chemotherapy can be lifesaving. Surgery for early relapse should be preceded by chemotherapy but surgery alone is appropriate where relapse occurs several years after primary treatment, although raised levels of tumour markers or extensive recurrence might be an indication for preliminary chemotherapy.

Adolescent↗
PubMed1996

Ovarian cancer, from the laboratory to the clinic: challenges for the future.

Over the past 20 years ovarian cancer has provided a vivid illustration of the successes, failures and challenges for the medical oncologist. During that time the results of treatment have substantially improved; in the West of Scotland for example, for women aged under 55, 3-year survival rates have increased from 36% to 50%. One reason for this was probably the introduction of effective agents such as cisplatin in the mid-1970s and then carboplatin in the mid-1980s. The recent introduction of taxoids promises further improvement in the future. It is important to remember, however, that the best results will be obtained by an optimal organization for the delivery of treatment; national audit studies have shown that factors such as management in integrated clinics can have a major impact on outcome. Nevertheless, the majority of patients still die from the disease; when relapse occurs, clinical drug resistance eventually proves fatal despite further treatment. What are the fundamental mechanisms by which this resistance develops, and what means are available to attempt its circumvention? Factors involved could be described as pharmacological or cellular. Pharmacological resistance might best be addressed by increasing the doses of the drugs used, particularly, cis- or carboplatin. Three years ago we published the results of a randomized trial of 2 doses of cisplatin in 191 patients. At that stage a highly significant median survival advantage for the higher dose (100 mg/m2) of cisplatin was seen. However, a recent updated analysis with a median follow-up of 4 1/2 years shows a reduction in the survival benefit, with 4-year overall survival rates for high- and low-dose cisplatin of 32.4% and 26.6%, respectively. This suggests that a population of drug resistant ovarian cancer cells will eventually emerge despite the use of initial higher doses of cisplatin. A more dose-intensive approach is being pursued with carboplatin, and it seems clear that dose-increments over standard therapy of at least 4-fold will be necessary, to justify further randomized trials. Meanwhile, the alternative approach to delivering high drug concentrations, i.e. intraperitoneal (i.p.) chemotherapy, clearly merits further study, particularly in the light of a recently reported study in patients with minimal disease, which showed a significant survival benefit for i.p. cisplatin treatment. Cellular factors will probably prove to be crucial; studies using various cell lines suggest that multiple mechanisms are likely to be involved and these will need to be examined in relevant clinical material. After DNA damage induced by a range of cytotoxic agents has taken place in ovarian cancer cells, the key to sensitivity/resistance may well be the ability of these cells to engage the process of apoptosis. Several genes are involved in control of this process; these include the p53 gene, mutations of which have been linked to cisplatin resistance in our laboratory studies, as well as in clinical trials with carboplatin. We have also demonstrated an association in ovarian cancer cell lines between cisplatin resistance and microsatellite instability (indicative of defective mismatch repair) and the clinical relevance of this link is also being pursued. A thorough understanding of underlying mechanisms may lead to the rational development of therapeutic means for circumventing cisplatin-resistance in ovarian cancer; the emergence of new classes of drug such as taxoids as topoisomerase I inhibitors offers further promise of improvement in outcome in the next few years.

Clinical Trials as Topic↗