Outpatient 5-fluorouracil, folinic acid and cisplatin in patients with advanced esophageal carcinoma

In a multicenter phase II study, 30 patients with unresectable, locally advanced or metastatic squamous cell or adenocarcinoma of the esophagus were treated with folinic acid 200 mg/m2/d, 5-FU 300 mg/m2/d, and cisplatin 20 mg/m2/d intravenously for 5 days every 4 weeks. Two of 13 patients with squamous cell carcinoma (SCC) had a complete response (CR), but one died of pneumonia after 9 months while still in CR, and the other still in CR after more than 5 years. Six other patients (3 SCC, 2 of 16 with adenocarcinoma, 1 mixed histology) had a partial response with a median duration of 9 months (range 5 to 57 + months) for an overall response rate of 27%. A further 6 patients (20%) had stable disease. Grade 4 neutropenia occurred in 6 patients (20%), with 5 requiring antibiotics for associated fever. Other grade 4 toxicities were nausea and vomiting (1), anemia (1), and thrombocytopenia (1); there were three early deaths (emphysema, cardiac arrest, pulmonary embolism). This combination appears to be an active, convenient regimen for advanced esophageal cancer, resulting in prolonged remission and survival in some patients.

Phase I-II study of 5-fluorouracil, leucovorin, doxorubicin, methotrexate, and long-term oral etoposide (FLAME) in unresectable or metastatic gastric cancer

The objective of this phase I-II study was to determine the efficacy and toxicity of combination chemotherapy with 5-fluorouracil, leucovorin, doxorubicin, methotrexate, and oral etoposide (FLAME) in patients with measurable unresectable or metastatic gastric cancer. Starting doses on the phase I study were as follows: methotrexate 50 mg/m2 intravenous bolus day 1; leucovorin 20 mg/m2 intravenous bolus days 2 through 4, starting 24 hours after the methotrexate dose; 5-fluorouracil 325 mg/m2 intravenous bolus 15 minutes after leucovorin days 2 through 4; doxorubicin 25 mg/m2 intravenous bolus day 8; and oral etoposide 50 mg/day for 14 days, starting on day 8. A new cycle started on day 28. A total of 42 patients were treated--10 patients in the phase I study and 32 patients in the phase II study. Dose-limiting toxicity was encountered in the phase I study on the second escalation step, when doxorubicin was escalated to 30 mg/m2 and 5-fluorouracil was escalated to 350 mg/m2. In the phase II study 28 patients (109 courses) were evaluable for toxicity. Neutropenia grade 3 or more was dose limiting and was documented in 12 patients (43%) during 22 treatment courses (20%). Neutropenia was associated with febrile neutropenia requiring hospitalization in four patients during five courses of therapy. Grade 3 stomatitis and grade 3 diarrhea was infrequent, documented in two patients (two courses) and three patients (four courses), respectively. All other toxicity was grade 1 and grade 2. The combined objective response rate in 38 evaluable patients entered in both studies was 23.3% (six partial responses and one complete response). Stable disease was documented in 15 patients (39.5%). The median survival for the 42 patients entered in both trials was 6.9 months (95% confidence interval, 5.9-8.5 months). The objective response rate and median survival for the combined group is comparable with that reported for the etoposide, leucovorin, and 5-fluorouracil (ELF), and 5-fluorouracil and methotrexate (FMTX) regimens in a recently reported, multicenter, phase III study.

In vitro carboplatin-mesna interaction in aqueous solution, human plasma and urine

The chemotherapeutic benefit of synergistic drug combinations and higher drug dosages has generated interest in the application of these regimens to cancer patients. A major obstacle in the application of these strategies to the treatment of cancer is the dose-limiting toxicities of drug combinations. Sodium 2-mercaptoethane-sulfonate (mesna), a chemoprotective drug, may reduce the nephrotoxicity of carboplatin [CBDCA, paraplatin, JM-8, cis-diammine (1,1-cyclobutane dicarboxylato) platinum II] when administered in combination chemotherapy. The purpose of this study was to evaluate, compare and contrast in vitro the interaction of mesna with carboplatin in aqueous solution, human plasma and urine. Carboplatin and mesna were incubated separately and together at clinically relevant concentrations in plasma and urine. The concentration of carboplatin was assayed by HPLC, and the decay of carboplatin alone and in combination with mesna was compared. The incubation of carboplatin with mesna in human plasma up to 8 days did not result in a statistically significant interaction: the half-life of carboplatin in plasma when it was combined with mesna was 1.62 +/- 0.08 (SE) days compared to 1.85+/- 0.04 (SE) days for carboplatin by itself. The incubation of drugs in fresh human urine up to 15 days gave a half-life of 3.43+/- 0.8 (SE) days for carboplatin alone and 2.78 +/- 0.7 (SE) days for carboplatin when it was combined with mesna. Our results show that carboplatin and mesna do not significantly interact in plasma. Although a statistically significant difference between the half-life of carboplatin and the half-life of the carboplatin/mesna combination is detected in urine, it is not likely to be clinically significant, as there is no significant interaction detected in the first 48 h). It is thus unlikely that mesna would substantially affect the pharmacokinetics of carboplatin when both are given together to patients as part of combination chemotherapy regimens.

A rapid reversed phase high performance liquid chromatographic method for the determination of docetaxel (Taxotere) in human plasma using a column switching technique

A rapid, simple and sensitive isocratic high performance liquid chromatography (HPLC) method was developed to measure the concentration of docetaxel in plasma samples with UV detection at 227 nm. The method uses a column switching technique with an Ultrasphere C18 column (75 x 4.6 mm ID, 3 mu, Altex, USA) as clean-up column and a CSC-nucleosil C8 column (150 x 4.6 mm ID, 5 mu, CSC, Montreal, Canada) as the analytical column. The mobile phase consisted of Phosphate buffer (30 mM, pH = 3)-acetonitrile (47:53, v/v) with the flow rates of 1.1 and 1.3 ml min-1 for clean-up and analytical columns, respectively. Paclitaxel was used as an internal standard. The plasma samples were extracted using a solid phase extraction method with Ammonium acetate (30 mM, pH = 5)-acetonitrile (50:50, v/v) as final eluent. The extraction method showed a recovery of 92% for docetaxel. In this system, the retention times of docetaxel and Paclitaxel were 7.2 and 8.5 min, respectively. The detection limit of docetaxel in plasma is 2.5 ng ml-1. This analytical method has a very good reproducibility (7.2% between-day variability at a concentration of 10 ng ml-1). It is applicable in clinical and pharmacokinetic studies.

Evaluation of apoptosis in four human tumour cell lines with differing sensitivities to cisplatin

Four human tumour cell lines were evaluated for their ability to undergo apoptosis when subjected to cisplatin or hyperthermia treatment. In an ovarian carcinoma line (A2780s) and its derivative cisplatin resistant line (A2780cp) the variation in response was expressed for both the colony survival endpoint and the apoptosis endpoint. Apoptosis was measured by the number of floating cells, DNA agarose gels, and electron microscopy. In fact, cisplatin resistance was expressed to a higher level for apoptosis, than colony survival in the A2780cp cell line compared to the A2780s line. The melanoma cell line (Sk Mel-3) also showed induced apoptosis by cisplatin treatment while the glioma line (U87MG) showed little to no apoptosis in response to cisplatin treatment. Hyperthermia (43 degrees C for 1 hour) induced apoptosis in the human melanoma cell line but not in the glioma cell line. These data indicate that, while both cisplatin and hyperthermia can induce apoptosis in human tumour cell lines, the degree of induction is highly cell line dependent.

A multicentre phase II study of carboplatin and prolonged oral etoposide in the treatment of cancer of unknown primary site (CUPS)

Cisplatin-based combination chemotherapy is frequently used to treat patients with carcinoma of unknown primary site (CUPS). Response rates in the literature range from 12% to 26% and median survival from 5 to 7 months. The goal of this study was to evaluate the combination of carboplatin and prolonged oral etoposide in patients with CUPS, with the hope of minimizing toxicity but improving efficacy and convenience. Treatment consisted of carboplatin, 300 mg m(-2) on day 1, and oral etoposide 50 mg on days 1-20, every 4 weeks for up to nine cycles. A total of 33 patients were treated and all were evaluable for toxicity. Non-haematological toxicity was mild to moderate, with the exception of one case of grade 4 stomatitis. Grade 4 leucopenia was observed in eight (24%) patients and sepsis in four (12%), with two and possibly three treatment-related deaths. For the 26 patients evaluable for response, the response rate was 23% with responses lasting a median of 11 months (range 7-13 months), with one patient still responding at 12 months. An additional nine patients (35%) had stable disease. Median survival for all patients was 5.6 months (range 2 weeks to 33 months). The combination of carboplatin with prolonged oral etoposide has moderate activity similar to that of other platinum-based regimens and is a well tolerated, convenient, outpatient regimen. Dosing according to estimated creatinine clearance to achieve a carboplatin AUC of 6.0 mg ml(-1) min might have decreased the incidence of severe myelotoxicity without compromising the regimen's efficacy.

Multiple resistance modulators combined with carboplatin for resistant malignancies: a pilot study

BACKGROUND

Chemotherapy resistance is probably multifactorial; hence, we assessed the feasibility of adding to carboplatin 6 concurrent resistance modulators in 53 patients with resistant cancers.

METHODS

Pentoxifylline and dipyridamole were added to carboplatin 400 mg/m2 in cohort 1, and metronidazole was also given in cohort 2. Mannitol and saline were administered in each cohort with the theoretical objective of improving carboplatin delivery to tumors by reducing blood viscosity. Because of excessive toxicity in cohort 2, cohort 3 received the same modulators as in cohort 2 but with a reduced dose of carboplatin (200 mg/m2). Subsequent patients had the following drugs added to those in the previous cohort: novobiocin (cohort 4), tamoxifen (cohort 5), ketoconazole (cohort 6). Cohort 7 patients received the 6 cohort 6 modulators along with carboplatin 300 mg/m2.

RESULTS

Thrombocytopenia was excessive in early cohorts with a carboplatin dose of 400 mg/m2, but was minimal at lower doses. Other toxicity was generally tolerable and reversible, particularly at carboplatin doses < or = 300 mg/m2, although gastrointestinal and neurological toxicity tended to worsen as additional modulators were added. No major responses (but 4 minor responses) were seen in this patient population with heavily pretreated or primarily resistant cancers.

CONCLUSIONS

Acceptable doses for phase II studies are carboplatin 300 mg/m2, 20% mannitol 250 ml plus normal saline 500 ml over 1 hr prior to carboplatin, pentoxifylline 700 mg/m2/day p.o. from 3 days before carboplatin to cessation of therapy, dipyridamole 100 mg/m2 p.o. q6h x 6 days starting 24 hr before carboplatin, metronidazole (750 mg/m2 p.o. 12 hr and immediately before, and 24 hr after carboplatin; 250 mg/m2 suppository p.r. 12 hr and immediately before, and 6 and 24 hr after carboplatin; and 500 mg/m2 i.v. right after carboplatin), novobiocin 600 mg/m2 p.o. q12h x 6 days starting 24 hr before carboplatin, and tamoxifen 100 mg/m2/day plus ketoconazole 700 mg/m2/day x 3 days starting the day before carboplatin, with oral dexamethasone and ondansetron as antimetics.

Acute and chronic effects of nicotine on anastomotic patency following ischemia/reperfusion

The effect of nicotine on anastomotic patency was studied using an isogenic rat-knee transplantation model. Animals were divided into experimental and control groups, with experimental animals exposed to either 40 days of twice-daily nicotine injections (Group 1-chronic exposure) or acute nicotine exposure by graft perfusion (Group 2-acute exposure). Four and 6 hr warm ischemia times were studied. Syngeneic rat knees were transplanted from donor to recipient by microvascular anastomosis of the femoral vessels. There was a statistically significant difference (p < 0.05) in anastomotic patency after 4 hr of ischemia in Group 1 animals exposed to nicotine (33 percent patency) vs. controls (89 percent patency). In addition, there was a statistically significant difference in anastomotic patency after 4 hr of ischemia in Group 2 animals exposed to nicotine (11 percent patency) vs. controls (67 percent patency). No significant differences between controls and Group 1 animals were noted in anastomotic patency after 6 hr of ischemia. Both acute and chronic nicotine exposure reduces anastomotic patency after short intervals of warm ischemia in vascularized composite tissue grafts. This detrimental effect is lost when the ischemic interval is prolonged to periods with poor anastomotic patency rates related to the ischemia/reperfusion itself.

Pilot study of multiple chemotherapy resistance modulators plus epirubicin in the treatment of resistant malignancies

We studied the toxicity and efficacy of adding to epirubicin five resistance modulators in the treatment of resistant solid tumors. Additional drugs were added in successive cohorts of patients, such that cohort 1 patients received two drugs along with their epirubicin, while cohort 4 patients received five modulators along with their epirubicin. Metronidazole, tamoxifen (cohort 1), dipyridamole (cohort 2), ketoconazole (cohort 3) and cyclosporin (cohort 4) were administered with epirubicin. A total of 22 patients were treated. Nausea and vomiting was usually mild to moderate. There was an unexpectedly high incidence of possible cardiac toxicity associated with treatment, although in some patients it was uncertain whether or not observed cardiac events were related to treatment. Granulocytopenia was significant in all four cohorts, but it was unclear whether it was increased by the modulators. There were two febrile neutropenic events in cohorts 1 and 2 successfully treated with antibiotics, and three septic deaths (one in each of cohorts 1, 2 and 4). It was elected to discontinue enrollment on the study prematurely in light of cardiac and other toxicity seen in the first two patients accrued in cohort 4. A single response was observed. While this approach is feasible, the observed toxicity and the difficulty patients experienced in ingesting the large number of prescribed pills will make further exploration of this approach difficult.

Effects of PALA on the pharmacokinetics of 5-fluorouracil

N-(phosphonacetyl)-L-aspartate (PALA) modulates the activity of 5-fluorouracil (5-FU) by inhibiting pyrimidine biosynthesis. A cross-over study was conducted to determine whether PALA affects the pharmacokinetic parameters of 5-FU in patients given 5-FU/folinic acid (FA). Six patients (3 males, 3 females) aged 63 4.3 (mean SD) years (body surface area of 1.84 18 m2) with metastatic colorectal carcinoma were given two courses of treatment. The treatment consisted of 250 mg/m2 of PALA on day 1 followed by 20 mg/m2 FA and 400 mg/m2 5-FU (5 min i.v. bolus injection) on days 2-5 in one cycle of treatment (PALA+). In another treatment cycle, these doses of 5-FU and FA were given for all 5 days without PALA (PALA-). The two courses were given four weeks apart. It was determined by random selection whether the course with PALA was given before or after the course without PALA. Blood samples were collected over a period of three hours, starting from the beginning of 5-FU infusion on days 2 and 5 of both courses. Plasma concentrations of 5-FU were determined by an HPLC technique. Pharmacokinetic parameters were calculated using a non-compartmental model. While there were no significant differences between pharmacokinetic parameters in the PALA+ vs PALA- courses, there was a trend towards a decreasing area under the curve (AUC) and increasing clearance (Cl) in PALA+ courses of treatment.

Phase II study of a one hour paclitaxel infusion in combination with carboplatin for advanced non-small cell lung cancer

PURPOSE

To determine the activity, toxicity, and optimal dose of paclitaxel when given by one hour infusion combined with carboplatin in advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Thirty-seven previously untreated patients with stage IIIB or IV NSCLC were enrolled. Paclitaxel was administered by one hour infusion at a dose of 175 mg/m2 for the first cycle, and was escalated up to 255 mg/m2 over successive cycles if tolerated. In the absence of toxicity, the carboplatin dose was kept constant at an area under the concentration-time curve (AUC) of 6. Cycles were repeated at 3-week intervals until progression or intolerable toxicity occurred.

RESULTS

Thirty-six patients were evaluable for toxicity and survival, and thirty-five for responses. The partial response rate was 10 of 35 (29%) and there were no complete responses. The median duration of response was 4.8 months (range 0.5-11.7 months). The median survival duration was 6.5 months, and 1 year survival was 31%. The mean paclitaxel dose was 188 mg/m2. Treatment was generally well tolerated. Four patients (11%) had febrile neutropenia. Five patients (14%) had grade 3 neuropathy, and 4 (11%) had grade 3 nausea and vomiting. Minor toxicities included alopecia, myalgias, arthralgias and stomatitis.

CONCLUSIONS

Paclitaxel and carboplatin is a well-tolerated regimen that can safely be given by a one hour paclitaxel infusion. The modest response rate observed in this study may be due to either the low dose-intensity of paclitaxel or the short infusion duration. Further trials to optimize the relative doses of paclitaxel and carboplatin are needed.

Retrospective comparative analysis of 5FU + low-dose folinic acid vs. 5FU + high-dose folinic acid in the treatment of metastatic colorectal cancer. The Ottawa experience

Two regimens of 5FU and folinic acid in the treatment of metastatic colorectal cancer were retrospectively analyzed. 33 patients received the high dose (HD) schedule (5FU 370 mg/m2 and Folinic Acid 200 mg/m2 i.v. on D1-5, every 4 weeks), 61 patients received the low dose (LD) schedule (5FU 400 mg/m2 and Folinic Acid 20 mg/m2 i.v. on D1-5, every 4 weeks). One patient in each group achieved a complete response, the overall response rate was 28% and 11% for the HD and LD groups, respectively. The median response duration was 183 days for the HD and 112 days for the LD group. The median survival duration was 387 days for the HD and 405 days for the LD group. The response rate and duration of response were higher in the HD group though this did not reach statistical significance. There was no difference in overall survival between the two patient groups. Neutropenia and gastro-intestinal symptoms were the most common toxicities, they were equal in both groups. One patient (3%) in the HD and 5 patients (9%) in LD group discontinued treatment due to toxicity. There were no treatment related deaths. It is concluded that low dose folinic acid in combination with 5FU is effective and produces similar toxicities as high dose folinic acid. It is concluded that low dose folinic acid in combination with 5FU is an effective alternative to high dose regimen in the palliative management of patients with metastatic colorectal cancer. However though it did not reach statistical significance the high dose regimen was associated with a higher response rate. This could have a significant effect when the combination is used in the adjuvant treatment of high risk patients.

Receptor-'Ck' dependent signalling regulates the LDL-receptor gene transcription

Evidence of a novel receptor, having affinity for cholesterol in lipoproteins and intrinsic tyrosine kinase activity (designated as Receptor 'Ck') prompted us to explore its role in LDL-dependent transcriptional regulation of apoprotein-B specific LDL receptor gene in human lymphocytes. The results of this study revealed that LDL dependent activation of this Receptor 'Ck' was essential for the regulation of apoprotein-B specific LDL receptor gene transcription. Further, by using various blockers of as well as simulating the Receptor 'Ck'-dependent signalling in human lymphocytes, we were able to show that Receptor 'Ck'-dependent signalling was involved in the LDL-dependent transcriptional regulation of 160 kDa apoprotein B specific LDL receptor gene. Based upon these results, we conclude that cholesterol derived from LDL. catabolism within the cell does not have any role in the transcriptional regulation of apoprotein B specific LDL receptor gene.

Primary vaginal urinary calculus following abdominoperineal resection of rectum

A rare case of primary vaginal calculus is presented. The case is unusual since it occurred after abdominoperineal resection for carcinoma rectum. The mechanism of stone formation in the patient has been discussed.

Arterial occlusion in patients with peripheral vascular disease treated with platinum-based regimens for lung cancer

BACKGROUND

Patients with cancer may be hypercoagulable, and smoking can cause both lung cancer and peripheral vascular disease. Cisplatin-based chemotherapy has been reported to cause a variety of vascular side effects.

CASE REPORTS

Five patients with bronchogenic carcinoma and peripheral vascular disease developed acute arterial occlusion soon after receiving a combination of cisplatin or carboplatin plus etoposide. All these patients had risk factors for atherosclerosis and three of them had preexisting known peripheral vascular disease.

CONCLUSIONS

The occurrence of acute arterial occlusion soon after initiation of chemotherapy suggests that it might have been a complication of this therapy. Hence, caution should be exercised when using platinum-based (and other?) chemotherapy in patients with known moderate or severe peripheral vascular disease.

Association of cisplatin nephrotoxicity with patient characteristics and cisplatin administration methods

OBJECTIVE

To assess factors that affect cisplatin nephrotoxicity.

METHODS

In 425 patients treated with cisplatin, we assessed the effect of pretreatment factors and treatment conditions on the rise in serum creatinine with the first course of cisplatin, on the maximum rise in serum creatinine over the entire course of the cisplatin therapy, and on residual nephrotoxicity after the last cisplatin treatment ended. (Because of the nature of the relationship between serum creatinine and creatinine clearance, rise in serum creatinine was divided by pretreatment creatinine squared.) Patients were dichotomized into the upper quartile versus the lower three quartiles of degree of nephrotoxicity. Multivariate analyses were based on logistic regression, controlling for cisplatin dose per course.

RESULTS

Controlling for cisplatin dose per course, factors most closely associated with nephrotoxicity during the first course of cisplatin were: serum albumin and potassium, body surface area, and administration of cisplatin over 2-5 days per course vs 1 day (negative associations). Controlling for cisplatin dose per course, the single factor most closely associated with maximum life-time cisplatin nephrotoxicity was concurrent use of a vinca alkaloid (negative association). Controlling for cisplatin dose per course, factors most closely associated with residual nephrotoxicity after the end of cisplatin therapy were cumulative dose of cisplatin, concurrent use of metoclopramide (positive associations), uric acid and concurrent use of phenytoin and a vinca alkaloid (negative associations). The association of nephrotoxicity with uric acid and with body surface area was felt to be an artifact resulting from its positive association with pretreatment serum creatinine. Nephrotoxicity during the first course of cisplatin also correlated significantly with autopsy kidney cortex platinum concentrations in 77 evaluable patients.

CONCLUSIONS

(1) While several factors correlated with cisplatin nephrotoxicity, most of the observed nephrotoxicity was not explained by the variables identified. (2) While most patients received intravenous hydration, patients receiving high hydration volumes did not have significantly less nephrotoxicity than patients receiving lower hydration volumes: (3) Of the variables identified, serum albumin, metoclopramide and phenytoin may have affected nephrotoxicity by altering cisplatin uptake into or distribution within the kidney.

Hydroxyurea Did Not Enhance the Clinical Response to Vinblastine in Patients with Anthracycline-Resistant Metastatic Breast Cancer

Background

Vinblastine is commonly used in metastatic breast cancer after anthracycline failure. The response rate to vinblastine is approximately 20%, with short duration of response. In vitro studies have shown that the addition of hydroxyurea resulted in increased accumulation of vinblastine in tumor cells and in loss of double minutes. We evaluated the combination of vinblastine and hydroxyurea in patients with anthracycline-resistant metastatic breast cancer.

Patients and Methods

Fourteen assessable patients with metastatic breast cancer were entered in the study. All patients had progressed on anthracyclines or progressed within 8 months of stopping anthracyclines. Patients received hydroxyurea (500 mg orally) every Monday, Wednesday and Friday starting one week before the first course of chemotherapy and continuing throughout treatment until disease progression. Vinblastine (6 mg/m2) was given intravenously every 21 days.

Results

The median number of courses for vinblastine was 3.5 (range, 1-6). Three patients had partial responses in soft tissue metastases (21%). Four patients had stable disease. Four patients had > grade 2 neutropenia, and 1 patient had grade 4 thrombocytopenia. There were 2 cases of grade 3 constipation, 2 of grade 3 nausea, and 1 each of grade 2 neuropathy and myalgia. There was no treatment-related mortality.

Conclusions

Low-dose hydroxyurea in combination with vinblastine has a 21% response rate in metastatic breast cancer after anthracycline failure. Toxicity was mild and generally reversible. At the adopted dose schedule of hydroxyurea, the antitumor activity of vinblastine in anthracycline-resistant metastatic breast cancer did not appear to be enhanced.

Sterol dependent LDL-receptor gene transcription in lymphocytes from normal and CML patients

Sterol regulatory element (SRE) has been recognized to regulate various key genes coding for especially low density lipoprotein (LDL)-receptor, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and HMG-CoA synthase known to play a crucial role in the cholesterol feedback mechanism. The deranged cholesterol feedback mechanism has been widely recognised in initiation as well as progression of various types of cancers including chronic myeloid leukaemia (CML). Consequently, the present study was addressed to understand this phenomenon and revealed the existence of a unique 47 kDa protein factor having affinity for this SRE sequence in lymphocytes from normal subjects as well as its absence in lymphocytes from untreated CML patients. However, this factor appeared when the CML patients achieved complete haematological remission (CHR) through alpha-interferon therapy. Further, an inverse relationship was also observed between sterol modulated LDL-receptor gene transcription and the binding affinity of this 47 kDa factor to the SRE sequence. Based upon these results we propose that alpha-interferon through its receptor initiates phosphatidic acid dependent signalling which in turn regulates the affinity of 47 kDa sterol regulatory element binding factor as well as LDL-receptor gene transcription in lymphocytes from CML patients.

Cytotoxicity, accumulation, and efflux of cisplatin and its metabolites in human ovarian carcinoma cells

Cisplatin (CP) is one of the most useful antineoplastic drugs. When CP is dissolved in human plasma, different metabolites are formed. Using the OV 2008 human ovarian cancer cell line, we examined the relative cytotoxicities of CP and its metabolites (aquated CP [AP], monomethionine CP [MP], bismethionine CP [BP], and a mixture of CP metabolites in ultrafiltrated human plasma [UP]) in vitro. By clonogenic assay, cell survival (percent of mean +/- SE) of OV 2008 cells exposed for 1 hr to 6.7 microM of CP was 9.8 +/- 0.7 and for its equal platinum contents of AP, MP, BP, and UP solutions were 3.3 +/- 0.7, 9.8 +/- 0.9, 15.9 +/- 1.1, 76.8 +/- 2.1, and 13.1 +/- 0.7, respectively. AP was the most cytotoxic species, and BP was the least cytotoxic species. Cellular platinum uptake (ng/10(6) cells) after addition of 0.33, 1.6, and 2.5 mM of each species for 1 hr was measured and a strong correlation was found between cytotoxicity of each CP metabolite and its corresponding cellular platinum (Pt) uptake (r = 0.997). There was a strong correlation between cytotoxicity of the CP metabolites and their DNA binding. With fractionation of these cells into DNA, nucleoplasm and cytoplasm, the highest platinum content was found on DNA. The most important factor that seems to be responsible for the cytotoxicities of the different CP metabolites is the amount of their associated intracellular accumulation, and particularly the degree of their binding to DNA.

Lymphocytes from CML patients lack a 47 kDa factor having affinity for a genomic sterol regulatory sequence

Deranged cellular cholesterol homeostasis has been widely recognized in the initiation as well as progression of various types of cancers including chronic myeloid leukaemia (CML). Since the human genomic sterol regulatory element (SRE) has been shown to regulate various key genes involved in this phenomenon, the present study revealed the existence of a unique 47 kDa protein factor having affinity for this SRE sequence in lymphocytes from normal subjects, as well as its absence in lymphocytes from untreated CML patients. However, this factor appeared when these CML patients achieved complete haematological remission (CHR) through alpha-interferon therapy. Furthermore, an inverse relationship was also observed between the LDL receptor gene expression at the transcriptional level and the binding affinity of this 47 kDa protein factor to the SRE sequence. Based upon these results we propose that this factor may have a role in pathophysiology of chronic myeloid leukaemia.

The integrity of cisplatin in aqueous and plasma ultrafiltrate media studied by 195Pt and 15N nuclear magnetic resonance

195Pt and 15N nuclear magnetic resonance (NMR) was used to study the chemical equilibria of cisplatin in water and plasma ultrafiltrate (PUF). Cisplatin was found to be stable for at least 2, but no longer than 5 months in a reconstituted clinical formulation, as determined by 195Pt NMR. In aqueous solution, the cis-PtCl2(NH3)2 195Pt and 15N NMR signal intensities decreased with time and the formation of [PtCl(H2O)(NH3)2]+ at PH values of 3.0, 6.5, 7.5 and 9.5 was observed within 24 h of sample preparation. In addition, [Pt(H2O)2(NH3)2]++ was observed at pH 3.0, and [PtCl(OH)(NH3)2] and [Pt(OH)2(NH3)2] were observed at pHs 7.5 and 9.5. During incubation of PUF with cisplatin for 35 h, 15N NMR signals for at least eight cisplatin derivatives appeared at different times, whereas only four were observed by 195Pt NMR. With our NMR protocols, the detection limit for quantifiable cisplatin derivatives is estimated at 500 microM using 195Pt NMR and < or = 200 microM using 15N NMR. In addition to providing useful information about the chemical stability of cisplatin and derivatives formed in aqueous solution, these magnetic resonance techniques, particularly 15N NMR, can provide useful information about the metabolism of cisplatin in biological regimes.

Chronic increased serum lipase without evidence of pancreatitis: tumor-derived lipase?

A 51-year-old man developed a large retroperitoneal tumor with liver and lymph node metastases; there was no radiological evidence of pancreatic involvement. Despite the progression of disease, results of laboratory tests, notably serum amylase, were normal except for minor increases in aspartate aminotransferase and gamma-glutamyltransferase and a marked increase in lipase. The increased lipase was not attributable to formation of macroenzyme. To determine the source of the lipase, we fractionated serum and a tumor biopsy homogenate, using electrophoresis. The lipase pattern obtained from the patient's serum differed from that seen in serum from a patient with acute pancreatitis. Additionally, the lipase pattern obtained from a homogenate of biopsy sample from the retroperitoneal tumor did not match the pattern observed for normal pancreas. Apparently, the source of this increased serum lipase activity was the nonpancreatic tumor.

Chronic increased serum lipase without evidence of pancreatitis: tumor-derived lipase?

A 51-year-old man developed a large retroperitoneal tumor with liver and lymph node metastases; there was no radiological evidence of pancreatic involvement. Despite the progression of disease, results of laboratory tests, notably serum amylase, were normal except for minor increases in aspartate aminotransferase and gamma-glutamyltransferase and a marked increase in lipase. The increased lipase was not attributable to formation of macroenzyme. To determine the source of the lipase, we fractionated serum and a tumor biopsy homogenate, using electrophoresis. The lipase pattern obtained from the patient's serum differed from that seen in serum from a patient with acute pancreatitis. Additionally, the lipase pattern obtained from a homogenate of biopsy sample from the retroperitoneal tumor did not match the pattern observed for normal pancreas. Apparently, the source of this increased serum lipase activity was the nonpancreatic tumor.

Failure of trochanteric osteotomy in total hip replacement: a comparison of two methods of reattachment

A retrospective study was undertaken to assess the rate of trochanteric union after a primary Charnley total hip replacement. In one group the trochanter was reattached with Wrobleski spring wire, and in the second group with a Dall-Miles clamp. Non-union occurred in 29% of each group. The high rate of failure may have implications for morbidity and function. Alternative surgical approaches for total hip replacement should be considered.

Pressure tuning infrared spectroscopic study of cisplatin-induced structural changes in a phosphatidylserine model membrane

The dynamic effect of cis-diamminedichloroplatinum(II) (DPP) and its aquated metabolite (DDP-OH) on a dimyristoylphosphatidylserine (DMPS) model membrane was investigated by pressure tuning vibrational spectroscopy. The native species (DDP-Cl) and the aquated species (DPP-OH) were both observed to bind to the carboxylate group of the serine as evidenced by a frequency shift of 1622-1620 cm-1. However, only DDP-OH was observed to bind to the phosphate group (PO(-)2). The binding of either drug to DMPS resulted in an increased pressure required to halt the reorientational fluctuations of the acyl chains, indicating that the distance between the chains were increased. The two drugs did not partition into the matrix of the hydrophobic section in the model membrane. Collectively, these data suggest that DDP-Cl and DDP-OH are capable of binding to the polar head group of DMPS, resulting in an enlargement of the area of the head and a subsequent increase in the intermolecular distance between the acyl chains.

Plasma lecithin: cholesterol acyltransferase and plasma lipolytic activity in preterm infants given total parenteral nutrition with 10% or 20% Intralipid

The effect of 10% or 20% Intralipid on lipid clearing enzymes, plasma lipids and apoproteins was investigated during the first 5 days after birth in 37 premature infants maintained on total parenteral nutrition; 21 infants received 20% and 16 received 10% Intralipid, respectively. Lipid was infused over a 20-h period at rates of 1, 2 and 3 g/kg/day on consecutive days. Plasma lecithin: cholesterol acyltransferase (LCAT) activity was low and increased significantly (p<0.05) only during infusions of 3 g/kg/day in both groups of infants. Plasma lipolytic activity was generally not affected by the regimen or preparation (10% or 20%) of Intralipid infused, except for higher (p<0.05) levels at 3 g/kg/day of 20% compared with prelipid infusion. Plasma triglyceride concentrations wer similar after 10% or 20% Intralipid, whereas plasma total cholesterol was significantly higher during infusion of 2 and 3 g/kg/day of 10% compared with 20% Intralipid. The efficient clearing of 20% Intralipid might be related to the lower lecithin: triglyceride ration which is compatible with the low LCAT activity of premature infants.

Procedural training in family practice residencies: current status and impact on resident recruitment

BACKGROUND

Although procedural training in family practice has recently received greater emphasis, the current status of this training in residency programs has not been reported. Considerable variation in procedural training among family practice residencies is allowed by the American Board of Family Practice and accreditation requirements. This study was performed to report the current status of procedural training in family practice residencies and to determine whether a correlation exists between the number of procedures taught in family practice residencies and successful resident recruitment.

METHODS

A one-page questionnaire was developed to determine availability of teaching and type of instructor for 24 selected procedures. This questionnaire was mailed to all 398 family practice residency directors in the United States. Data from the survey were compared with the published residency match results in 1993 and 1994.

RESULTS

Questionnaires were received from 363 programs, for a response rate of 91 percent. The current status of training in these procedures, presented by program type and geographic region, reflects considerable regional variation. Training in colposcopy and in cardiac stress testing was reported to be available in a greater percentage of programs than in previous studies. A significant positive correlation was found between the number of procedures taught by family physicians and residency match results.

CONCLUSIONS

The 91 percent response rate lends credibility to this status report and indicates that family practice program directors recognize procedural training as an important issue. The trend toward greater availability of procedural training in family practice residencies is confirmed for selected procedures. Emphasis on procedural training by family physicians has a positive correlation with successful resident recruiting. The impact on medical student interest in family practice deserves further study.

Factors affecting platinum concentrations in human surgical tumour specimens after cisplatin

We assessed factors which affect cisplatin concentrations in human surgical tumour specimens. Cisplatin 10 mg m-2 was given i.v. to 45 consenting patients undergoing surgical resection of neoplasms, and platinum was assayed in resected tumour and in deproteinated plasma by flameless atomic absorption spectrophotometry. By multiple stepwise regression analysis of normalised data, patient characteristics that emerged as being most closely associated (P < 0.05) with tumour platinum concentrations (after correcting for associations with other variables) were tumour 'source' [primary brain lymphomas, medulloblastomas and meningiomas ('type LMM') > 'others' > lung cancer > head/neck cancer > gliomas) or tumour 'type' (LMM > brain metastases > extracerebral tumours > gliomas), serum calcium and chloride (positive correlations) and bilirubin (negative). Tumour location (intracranial vs extracranial) did not correlate with platinum concentrations. If values for a single outlier were omitted, high-grade gliomas had significantly higher platinum concentrations (P < 0.003) than low-grade gliomas. For intracranial tumours, the computerised tomographic scan feature that correlated most closely with platinum concentrations in multivariate analysis was the darkness of peritumoral oedema. Tumour source or type is a much more important correlate of human tumour cisplatin concentrations than is intracranial vs extracranial location. Serum calcium, chloride and bilirubin levels may affect tumour cisplatin uptake or retention. CT scan characteristics may help predict cisplatin concentrations in intracranial tumours.

High dose doxorubicin plus cisplatin in the treatment of unresectable mesotheliomas: report of four cases

Only a very small proportion of all patients with mesotheliomas can be cured surgically. Both radiotherapy and standard chemotherapy are generally considered to be of only limited usefulness. In this paper, we report four patients with unresectable mesotheliomas treated with the combination of cisplatin 105-120 mg/m2 plus doxorubicin 90 mg/m2. Toxicity was substantial, in that all four patients developed neutropenic sepsis and other grade 3 toxicity, but there were no treatment-related deaths. There were two patients with complete remissions (one persisting at > 4 years), one partial remission, and one stable disease with marked symptomatic improvement. This combination is toxic, but the anecdotal evidence of efficacy is suggestive that it may possibly be more active than lower doses of chemotherapy. It warrants further study in good performance status patients with unresectable mesotheliomas.

Duration of intravenous antibiotics for patients with neutropenic fever

BACKGROUND

Standard therapy for febrile neutropenia after chemotherapy has consisted of intravenous antibiotic until resolution of both fever and neutropenia. We attempted to shorten the hospital stay by discontinuing intravenous antibiotics in blood culture negative patients who remained clinically stable and afebrile for 48 hours.

PATIENTS AND METHODS

Febrile neutropenic admissions of non-leukemic patients were reviewed. They were divided by three consecutive six month intervals into Group 1 (prior to initiation of the policy), Group 2 (after the policy was instituted), and Group 3 (to monitor the implementation of the policy after the initial six months).

RESULTS

There were 134 admissions for neutropenic fever. Median duration of intravenous antibiotic for Group 1 was 7 days (95% Confidence Interval 6-9). It was significantly decreased to 5 days (4-6) and 4 days (3-5) for Groups 2 and 3 respectively (p = 0.004 and p < 0.001). Median duration of hospital stay for Group 1 was 10 days (7-13). It was also significantly decreased to 7 (5-8) and 6 days (5-7) for Groups 2 and 3 respectively (p = 0.04 and p = 0.002).

CONCLUSION

Early discontinuation of intravenous antibiotics in patients with negative blood culture who remain afebrile and clinically stable for 48 hours results in shorter duration of hospital stay with potential for reduction in hospital costs.