mRNA in situ hybridization of TIGR/MYOC in human trabecular meshwork

PURPOSE

To determine the distribution of mRNA expression of the trabecular meshwork-induced glucocorticoid response protein/myocilin (TIGR/MYOC) in human trabecular meshwork.

METHODS

In situ hybridization using a 1.25-kb probe obtained from reverse transcription-polymerase chain reaction of TIGR/MYOC cDNA was performed to determine the location of cell labeling within the different regions of the meshwork. The effect of dexamethasone on the pattern of labeling was studied in organ cultured meshwork. Trabecular meshwork from three sources was studied: enucleated eyes obtained at autopsy, trabeculectomy specimens obtained during filtration surgery, and meshworks from anterior segments in perfusion organ culture. Hybridization was performed on frozen sections, paraffin sections, and sections from JB-4 plastic-embedded tissue.

RESULTS

Labeling for TIGR/MYOC mRNA was present in most trabecular cells of the uveal, corneoscleral, and juxtacanalicular regions but only variably present in the endothelial cells of Schlemm's canal. A similar pattern was found in the trabeculectomy specimens from eyes with primary open-angle or pseudoexfoliative glaucoma. Dexamethasone treatment increased the labeling intensity and number of labeled cells in meshwork, and also the number of labeled endothelial cells of Schlemm's canal. Fresh tissue processed within 12 hours postmortem gave more consistent labeling than older tissue, although some label was found up to 48 hours postmortem. Labeling was found in tissue from all three sources, and with all three embedding techniques; JB-4 sections provided the best morphologic resolution.

CONCLUSIONS

In situ hybridization reveals that mRNA expression for TIGR/MYOC is present in most cells in all regions of the meshwork but only variably present in the endothelial cells of Schlemm's canal. Dexamethasone treatment increased the number and intensity of labeled cells, and also increased the number of labeled cells in the endothelial lining of Schlemm's canal.

Sequence-dependent antagonism between tamoxifen and methotrexate in human breast cancer cells

High-dose methotrexate (MTX) cytotoxicity is decreased in MCF-7 breast cancer cells when the chemoendocrine agent tamoxifen (TAM) is given to cells 24 hours prior to MTX (early TAM). However, when breast cancer cells are exposed to TAM 24 hours after MTX (delayed TAM), MTX cytotoxicity is enhanced by TAM. The growth of cells exposed to 10 microM TAM and 10 microM MTX alone or in combination with early TAM plus MTX had the following order: TAM > TAM (early) + MTX > MTX. The percentages of control rates for TAM, MTX, and TAM (early) + MTX are 74.71 +/- 1.36%, 22.13 +/- 2.76%, and 38.17 +/- 2.75%, respectively. The inhibitory sequence from cells exposed to MTX + TAM (delayed TAM), MTX and TAM alone is MTX + TAM (delayed TAM) > MTX > TAM; and the percentages of control rates were 16.87 87% (MTX + TAM [delayed TAM]), 25.92 +/- 2.14% (MTX), and 54.08 +/- 14.79% (TAM). These studies suggest that: (a) the interactions between TAM and MTX are sequence-dependent; (b) TAM antagonizes the effect of MTX when TAM administration precedes MTX; and (c) TAM enhances the effect of MTX when TAM administration follows MTX.

A Phase I Trial of Outpatient Weekly Docetaxel and Concurrent Radiation Therapy for Stage III Unresectable Non–Small-Cell Lung Cancer: A Vanderbuilt Cancer Center Affiliate Network (VCCAN) Trial

Docetaxel has demonstrated activity as a radiosensitizer in numerous preclinical studies, probably due to its role as a cell cycle synchronizer for the G2/M radiosensitive phase of the cell cycle. We conducted a phase I trial to determine the maximum-tolerated dose (MTD) and dose-limiting toxicities (DLT) of docetaxel with concurrent thoracic radiation therapy (TRT) to patients with unresectable stage III non small-cell lung cancer (NSCLC). Fifteen patients were entered into this study. Docetaxel was administered as a 1-hour intravenous (I.V.) infusion, repeated every week for 6 weeks with starting dose of 20 mg/m2. Doses were escalated in 10 mg/m2 increments in successive cohorts of three new patients, if tolerated. Unacceptable toxicity was defined as grade = 3 nonhematologic or hematologic toxicity according to Eastern Cooperative Oncology Group (ECOG) toxicity criteria. TRT was administered to the primary tumor and regional lymph nodes (40 Gy) followed by a boost to the tumor (20 Gy). At the first dose level (20 mg/m2/week), one patient developed grade 4 hyperglycemia and accrual was expanded to five patients. At the second level (30 mg/m2/week), two out of six patients developed grade 3 esophagitis. At the third level (40 mg/m2/week), two out of four patients developed grade 3 esophagitis and one patient developed grade 3 pulmonary toxicity. The weekly docetaxel MTD with concurrent radiation therapy (RT) was found to be 30 mg/m2. The DLT was esophagitis and pulmonary toxicity. Other toxicities encountered included skin reaction, nausea and vomiting, as well as diarrhea. Additionally, there were no treatment-related mortalities or late-occurring toxicities. Esophagitis was the principal DLT of concurrent weekly docetaxel and thoracic radiation in the outpatient setting. The MTD of concurrent weekly docetaxel with TRT is 30 mg/m2 weekly for 6 weeks. This study is still open to accrual with weekly docetaxel and TRT in locally advanced NSCLC patients.

Locally advanced, unresectable non-small cell lung cancer: new treatment strategies

Approximately 40% of non-small cell lung cancer (NSCLC) patients present with locally advanced, unresectable lesions. Treatment with thoracic radiotherapy yields survivals averaging just 9 to 10 months, and long-term survival at 5 years is poor. Recent studies indicate that chemotherapy followed by thoracic radiotherapy improves 5-year survival by three- to fourfold. Nevertheless, most patients do ultimately die of the underlying disease. New strategies designed to enhance local tumor control-use of radiation-sensitizing drugs, three-dimensional treatment planning techniques, or altered radiation fractionation schedules-may further improve survival outcome. In addition, newer cisplatin-based regimens containing either paclitaxel or vinorelbine improve survival over that achieved with older vinca alkaloid or podophyllotoxin combination regimens. Accordingly, the newer drug regimens combined with radiotherapy can be expected to further improve survival in this subset of NSCLC patients. Prospective studies are underway to test this conjecture.

Evolution of cisplatin-based chemotherapy in non-small cell lung cancer: a historical perspective and the eastern cooperative oncology group experience

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in most industrialized nations, including the United States. Frequently, patients with unresectable disease are treated with symptomatic care alone or, in the case of locally advanced, unresectable lesions, with radiotherapy alone. In general, chemotherapy is viewed as ineffective, and therefore rarely recommended except by medical oncologists. Over the past 2 decades, however, it has become clear that chemotherapy, and in particular cisplatin-based chemotherapy, provides a modest survival advantage. In addition, recent studies indicate that chemotherapy can improve tumor-related symptoms and quality of life. With modern chemotherapy, median survival averages around 9 to 10 months in advanced NSCLC, a figure comparable to that achieved with treatment of extensive-stage small cell lung cancer, a malignancy generally viewed as chemotherapy sensitive. Importantly, existing data indicate that chemotherapy is also cost-effective. Given these observations, it is appropriate today for patients with advanced NSCLC to receive chemotherapy.

Patterns of practice survey for nonsmall cell lung carcinoma in the U.S

BACKGROUND

Nonsmall cell lung carcinoma comprises approximately 75% of all lung carcinoma cases in the U.S. Newly evolving strategies have created considerable controversy regarding the optimal treatment for patients diagnosed with this disease.

METHODS

A 17-item survey was designed to collect demographic data and information regarding practice patterns for nonsmall cell lung carcinoma, including patient assessment, treatment approaches, and roles of chemotherapy and radiotherapy. Surveys were mailed in the summer of 1997 to approximately 9200 oncologists of all types throughout the U.S. Practice settings included private office, private hospital, academic, university-affiliated office, government, and Veterans Administration institutions.

RESULTS

Approximately 10% of the oncologists responded (n = 979), including 499 medical oncologists (51%), 464 radiation oncologists (47%), and 16 others (2%). For the adjuvant treatment of surgically resected N1-2 disease, combined modality treatment was preferred over radiation therapy alone by medical oncologists (48% vs. 16%; P<0.001) and radiation therapy alone was preferred over combined modality treatment by radiation oncologists (55% vs. 38%; P<0.001). The combination of paclitaxel and carboplatin was the preferred first-line regimen for all stages of nonsmall cell lung carcinoma by the majority of medical oncologists (55%), whereas the majority of radiation oncologists (58%) chose the combination of etoposide and platinum. With regard to the optimal combined modality approach, respondents were divided evenly between concurrent chemoradiotherapy (34%) and sequential chemoradiotherapy (31%). Overall, respondents reported basing treatment decisions largely on published literature (55%) compared with personal experience (19%), seminars and colleagues (16%), and clinical trial availability (10%) (P<0.001).

CONCLUSIONS

This survey confirms many differences in practice patterns among medical oncologists and radiation oncologists in the treatment of patients with nonsmall cell lung carcinoma and suggests the need for the multidisciplinary management of this entity. In addition, the current study demonstrates that reliance on the medical literature as a basis for treatment steadily declines the longer the physician has been in practice.

Induction chemotherapy before surgery for early-stage lung cancer: A novel approach. Bimodality Lung Oncology Team

OBJECTIVE

This phase II trial assessed the feasibility, as measured by response rate, toxicity, resectability rate, and surgical morbidity and mortality rates, of perioperative paclitaxel and carboplatin chemotherapy in patients with early-stage non-small cell lung carcinoma.

METHODS

All patients required negative mediastinoscopy results and adequate medical parameters to undergo induction chemotherapy and an operation. Superior sulcus patients were excluded. Chemotherapy consisted of paclitaxel 225 mg/m(2) over 3 hours and carboplatin (area under the curve = 6) every 21 days for 2 cycles preoperatively. Three postoperative cycles of chemotherapy were planned for patients undergoing complete resection.

RESULTS

Between June 1996 and July 1998, 94 patients were entered into the study. Sixty-five (69%) were men, and the median age was 64 years (range, 34-79 years). After induction chemotherapy, 53 of 94 (56%; 95% confidence interval, 46%-67%) had a major objective response, 88 (94%) underwent surgical exploration, and 81 (86%; 95% confidence interval, 78%-92%) underwent complete resection. Reasons for not undergoing an operation included disease progression (n = 3), clinically unresectable status (n = 1), death (n = 1), and patient lost to follow-up (n = 1). Two postoperative deaths occurred. Six (6%; 95% confidence interval, 0%-13%) pathologic complete responses were observed. Ninety (96%) patients received the planned preoperative chemotherapy versus 45% receiving postoperative chemotherapy. No unexpected chemotherapy or surgical morbidity occurred. The 1-year survival is currently estimated at 85%, and the median survival has not yet been reached.

CONCLUSIONS

Induction chemotherapy with paclitaxel and carboplatin is feasible and produces a high response rate with acceptable morbidity and mortality rates in early-stage non-small cell lung carcinoma. A prospective randomized trial comparing 3 cycles of induction chemotherapy and surgery with surgery alone in early-stage non-small cell lung carcinoma is planned.

Management of small cell lung cancer: current state of the art

Small cell lung cancer (SCLC) is a common malignancy that is rapidly fatal if left untreated, with most patients surviving < 6 months. Currently, patients with SCLC are treated with chemotherapy with or without thoracic radiotherapy. Randomized trials have demonstrated the superiority of multiagent regimens over single-agent therapies, with the combination of cisplatin and etoposide being the initial regimen of choice for most patients, regardless of stage at presentation. Dose escalation, weekly chemotherapy, alternating noncross-resistant chemotherapy, and maintenance chemotherapy have been evaluated in SCLC, with no convincing data to date demonstrating an advantage for these strategies over conventional treatment strategies. Second-line therapy may be effective in selected patients, depending on the interval between primary treatment and recurrence, response to primary therapy, and the agents used for initial treatment. Radiotherapy is generally accepted as an essential component of optimal management of limited-stage disease, although sequencing, timing, fractionation, dose, and field size remain less than adequately defined. Finally, the routine use of prophylactic cranial irradiation remains controversial, and currently should be reserved for patients in complete remission.

Modulation of myocilin/TIGR expression in human trabecular meshwork

PURPOSE

To study factors that modulate myocilin/trabecular meshwork inducible glucocorticoid response protein (TIGR) mRNA expression in human trabecular meshwork (TM).

METHODS

mRNA from fresh TM of four human donors, from perfused anterior segment organ cultured TM of three donors, and from four primary TM cell lines of different donors was isolated. The full length cDNA of myocilin/TIGR was cloned from TM mRNA using a polymerase chain reaction approach and used as probe for northern blot analysis hybridization. Trabecular meshwork cell cultures were treated with transforming growth factor (TGF)-beta1 (1 ng/ml), dexamethasone (10(-7) M), and mechanical stretch (10%).

RESULTS

mRNA for myocilin/TIGR could be readily detected by northern blot analysis hybridization in 2 to 3 microg of total RNA from all fresh and all organ-cultured TM samples. In contrast, no mRNA for myocilin/TIGR could be detected in 20 microg of total RNA isolated from three different primary TM cell lines. Only one TM cell line had a baseline expression of myocilin/TIGR, which was 35- to 55-fold lower than that of fresh or organ-cultured TM samples. Treatment of TM cell cultures with dexamethasone for 1 day markedly increased expression of myocilin/TIGR mRNA, an effect that was even more pronounced after 3 days of treatment. Treatment with TGF-beta1 for 24 hours had no effect; however, after 3 and 12 days of treatment a 3.8- and 4-fold increase in myocilin/TIGR mRNA expression was observed. Expression of myocilin/TIGR mRNA was also increased after 10% mechanical stretch; however, in contrast to the effects of TGF-beta-1, this effect was observed much earlier (8-24 hours) after treatment.

CONCLUSIONS

Dynamic mechanical stimuli maintain myocilin/TIGR expression in TM in situ and lack of these stimuli in monolayer cell cultures might be involved in downregulation of myocilin/TIGR expression.

Tourniquet inflation during arthroscopic knee ligament surgery does not increase postoperative pain

PURPOSE

A double-blind clinical trial was conducted to determine the effect of inflation of a thigh tourniquet during anterior cruciate ligament repair on arthroscopic visibility, duration of procedure, postoperative pain and opioid consumption.

METHODS

Thirty patients were randomly allocated into two groups; Group I had the thigh tourniquet inflated during surgery whereas the tourniquet was not inflated in Group II patients. All patients received standardized general anesthesia and postoperative pain management. Supplemental analgesia was provided with i.v. morphine via a patient-controlled analgesia (PCA) apparatus. Verbal pain rating scores (0-10) were obtained after surgery.

RESULTS

Arthroscopic visibility was impaired in Group II patients (P < 0.0001), but this was ameliorated by increased irrigation flow or addition of epinephrine. Duration of surgery was similar in both groups. There was no difference between groups in postoperative morphine consumption (9.8 +/- 7.1 mg in Group I vs 11.4 +/- 10.2 mg in Group II) or in postoperative pain scores between groups.

CONCLUSION

Inflation of a thigh tourniquet did not result in increased pain or opioid consumption after arthroscopic ACL surgery. Arthroscopic visibility was somewhat impaired in some patients without the use of tourniquet. Finally, the duration of the surgical procedure was not increased in patients where the tourniquet was not inflated during the ACL repair.

Selectivity in human breast cancer and human bone marrow using trimetrexate in combination with 5-fluorouracil

The growth inhibitory effect of trimetrexate (TMQ) is maintained in MCF-7 breast cancer but is decreased in Hs 824.T human bone marrow cells by a priming- and non-toxic 5-fluorouracil (5-FU) dose. Incubation of MCF-7 breast cells with 10 microM TMQ alone or in combination with 10 M 5-FU (TMQ 2 h prior to 5-FU [TMQ/5-FU] or 5-FU 2 h prior to TMQ[5-FU/TMQ]) resulted in similar inhibitory effects but dissimilar effects occurred in Hs 824.T bone marrow. In breast cancer, the percentage differences among TMQ and TMQ/5-FU, TMQ and 5-FU/TMQ, and TMQ/5-FU and 5-FU/TMQ on growth rates, respectively, were 3.56%, 2.35%, and 1.68%. The percentage differences on growth rates of TMQ and TMQ/5-FU, TMQ and 5-FU/TMQ, and TMQ/5-FU and 5-FU/TMQ in bone marrow, respectively, were 5.76%, 30.03% (significant protection by 5-FU, i.e. the inhibitory effect of 5-FU/TMQ < or = TMQ), and 35.78% (sequence dependent). The growth rates of breast cancer and bone marrow cells in the presence of 5-FU were 96.03 +/- 1.17% and 94.59 +/- 1.15%, respectively, of control rates. These studies suggest that (a) TMQ and 5-FU combinations on the growth of MCF-7 breast cancer cells are independent of sequence of administration and best related to TMQ and (b) a priming- and non-toxic 5-FU dose protects against TMQ toxicity in human bone marrow while not affecting the maximum inhibitory effect of TMQ in breast cancer.

Probability of filtration surgery in patients with open-angle glaucoma

OBJECTIVE

To investigate the probability of undergoing filtration surgery in either 1 or both eyes in patients in whom open-angle glaucoma was newly diagnosed.

METHODS AND DESIGN

A retrospective community-based study of 295 residents of Olmsted County, Minnesota, in whom open-angle glaucoma was newly diagnosed between January 1, 1965, and December 31, 1980, was performed. Kaplan-Meier methods were used to estimate the cumulative probability of undergoing filtration surgery during a 20-year period.

RESULTS

At 20 years of follow-up, the Kaplan-Meier cumulative probability of undergoing filtration surgery in at least 1 eye was estimated to be 23% (95% confidence interval, 16%-30%), and in both eyes the estimate was 12% (95% confidence interval, 6%-17%). Patients with optic nerve damage at the time of diagnosis were more likely to undergo surgery than patients with elevated intraocular pressure but no damage (1 eye, 39% vs 15%; both eyes, 27% vs 5%).

CONCLUSION

This retrospective study of a white population newly diagnosed as having and treated for open-angle glaucoma indicates that while most patients did not undergo filtration surgery in the course of glaucoma therapy, at least one third of those with glaucomatous damage at the time of diagnosis underwent filtration surgery.

Phase II study of irinotecan plus cisplatin in patients with advanced non-small-cell lung cancer

PURPOSE

To evaluate the antitumor efficacy and safety of a combination of irinotecan (CPT-11) and cisplatin in patients with inoperable non-small-cell lung cancer (NSCLC). A secondary objective was to characterize the pharmacokinetics and pharmacodynamics of CPT-11 and its active metabolite, SN-38.

PATIENTS AND METHODS

Patients with stage IIIB or IV NSCLC were treated with repeated 4-week courses comprising CPT-11 (60 mg/m(2)) administered on days 1, 8, and 15, and a single dose of cisplatin (80 mg/m(2)) after CPT-11 administration on day 1.

RESULTS

Fifty-two patients were enrolled, including 33 men and 19 women. The median age was 61 years (range, 29 to 79 years). Southwest Oncology Group performance status was 0 in 12 patients, 1 in 32 patients, and 2 in eight patients. Eleven and 41 patients had stage IIIB and IV disease, respectively. Objective responses occurred in 28.8% of patients (15 of 52; 95% confidence interval, 16.5% to 41.2%). The median survival duration was 9.9 months (range, 1.6 to 30.8 months). The 1-year survival rate was 37%. Grade 3/4 adverse events consisted primarily of nausea (32. 7% ) or vomiting (13.5%), late-onset diarrhea (17.3%), and neutropenia (46.1%). The study design led to preferential modification of CPT-11 doses, resulting in CPT-11 dose attenuations to < or = 40 mg/m(2) in the majority of patients (31 of 52; 60%), whereas dose reductions of cisplatin were uncommon. CPT-11 pharmacokinetic parameters were comparable to those reported previously in single-agent studies.

CONCLUSION

CPT-11/cisplatin is an active combination regimen with manageable toxicity in the therapy of stage IIIB/IV NSCLC. Future studies should be designed with schedules and dose modification provisions that avoid unnecessary CPT-11 dose reductions to exploit more directly the therapeutic synergy of these agents.

Treatment Strategies for Metastatic Non–Small-Cell Lung Cancer

This review article provides evidence to support the use of chemotherapy for non small-cell lung cancer (NSCLC). Chemotherapy plays an important role in the management of advanced NSCLC. Chemotherapy offers symptom palliation, modest but real survival benefits and improves quality of life. The survival benefits achieved with newer drug regimens offer chemotherapy as a strategy for the treatment of NSCLC patients with good performance, no medical or psychological contraindications.

National survey on prophylactic cranial irradiation: differences in practice patterns between medical and radiation oncologists

PURPOSE

Prophylactic cranial irradiation (PCI) in the treatment of small cell lung cancer (SCLC) patients remains controversial in the oncology community because of its potential for long-term toxicity and unproven survival benefit in randomized trials. A national survey of 9176 oncologists was conducted to characterize the use of PCI with regard to physician demographics, patient characteristics, and oncologists' beliefs.

METHODS

Data was collected via a questionnaire letter survey. Biographical data, treatment patterns, and clinical impressions were analyzed by the generalized linear model and generalized estimating equations method.

RESULTS

There were 1231 responders overall (13.4% of those surveyed), including 628 (51%) radiation oncologists (RO), 587 (48%) medical oncologists (MO), 8 (0.6%) surgical oncologists, and 8 (0.6%) from other oncology subspecialties. Of respondents, 74% overall recommend PCI in limited-stage patients, including 65% of MO and 82% RO (p = 0.001). Of responders who recommend PCI in limited-stage patients, 67% do so only after complete response to initial therapy. Only 30% of respondents recommend PCI for extensive-stage SCLC patients (p = 0.001), and 94% of these recommend PCI only when those patients have a complete response after initial therapy. Interestingly, 38% of responding MO feel that PCI improves survival of limited-stage patients, but only 11% believe PCI improves quality of life. Of the RO, 48% believe PCI improves survival in limited-stage SCLC, and 36% feel PCI improves quality of life (p < 0.05 and p < 0.01, respectively). MO responders believe PCI causes late neurological sequelae more often than do RO responders (95% vs. 84%, p < 0.05), with impaired memory (37%), chronic fatigue (19%), and loss of motivation (13%) as most commonly seen side effects. Only 1.5% overall, however, routinely obtain neuropsychiatric testing in PCI patients, and 42% overall never obtain them.

CONCLUSION

Results confirm that oncologic subspecialists have statistically significant differences in opinion regarding the use of PCI. However, these differences may not translate into large differences in clinical practice. Most oncologists continue to recommend PCI in limited-stage SCLC patients, despite many believing PCI may not provide a survival advantage nor improve quality of life.

Concurrent paclitaxel and thoracic irradiation for locally advanced esophageal cancer

Esophageal cancer is a major cause of morbidity and mortality worldwide. Although patients often present with apparently resectable disease, systemic spread frequently occurs before the development of symptoms and detection of tumor. The use of combined chemoradiation therapy, particularly before resection, appears to prolong survival and increase cure rates in certain histologic subtypes. Four randomized phase III trials compared preoperative chemoradiotherapy plus surgery with surgery alone. In trials including only patients with squamous histology, no improvement in survival was observed with preoperative chemoradiation therapy; however, in a trial including only patients with adenocarcinoma histology, improved median and overall survival were observed. Paclitaxel has been evaluated as a single agent in a phase II trial in previously untreated patients with locally advanced unresectable or metastatic esophageal cancer; the overall response rate was 32% and median survival was 13.2 months. Paclitaxel-based combinations also have been evaluated in esophageal cancer; particularly encouraging preliminary results have been achieved with paclitaxel/cisplatin/5-fluorouracil. Because paclitaxel is a potent radiosensitizer, it also has been evaluated in combination with radiation therapy for esophageal and other thoracic cancers, alone and in combination with other chemotherapeutic agents. Preliminary results suggest that neoadjuvant therapy with paclitaxel-based combinations (including 5-fluorouracil and cisplatin) and radiation is highly active, with variable toxicity. A goal of future trials is to assess paclitaxel-based combined modality therapy in combination with other new chemotherapeutic agents.

5-Fluorouracil simultaneously maintains methotrexate antineoplastic activity in human breast cancer and protects against methotrexate cytotoxicity in human bone marrow

High-dose methotrexate (MTX) cytotoxicity is maintained in MCF-7 breast cancer cells but reduced in Hs824.T human bone marrow by a priming and nontoxic 5-fluorouracil (5-FU) dose. When MCF-7 breast or Hs824.T bone marrow cells are incubated with 10 microM 5-FU and 10 microM MTX for 48 h, the growth rates of breast cancer cells were 97.59 +/- 0.97% and 21.81 +/- 3.33% of the control rate, respectively, and the growth rates of bone marrow cells were 90.61 +/- 3.71% and 29.58 +/- 2.99% of the control rate. The combinations of 5-FU 2 h prior to MTX or MTX 2 h prior to 5-FU followed by a 48 h incubation, respectively, gave growth rates of 20.96 +/- 2.44% and 19.86 +/- 2.56% of the control rate for MCF-7 cells. In bone marrow cells, the combinations of 5-FU 2 h prior to MTX or MTX 2 h prior to 5-FU followed by a 48 h incubation, respectively, gave growth rates of 79.66 +/- 7.41% (protection) and 31.39 +/- 1.77% of the control rate. Similar patterns to bone marrow emerges in platelets. These studies suggest that: a) MTX and 5-FU combination on the growth of human MCF-7 breast cancer cells is independent of sequence; and b) a priming-dose of 5-FU will protect bone marrow from MTX cytotoxicity but not breast cancer cells. Therefore, a priming and non-toxic dose of 5-FU and MTX may have maximum antineoplastic activity while at the same time provide protection to the hematopoietic system.

Systemic thermal injury in anesthetized rabbits causes early pulmonary vascular injury that is not ablated by lazaroids

PURPOSE

To study the effects of a systemic thermal injury on the pulmonary vasculature with and without inhibitors of lipid peroxidation (U74389G).

METHODS

In a prospective, placebo control, randomized, and blinded multi-group study, burn shock was induced by scalding thermal injury (65C) to 35% body surface area in rabbits (n = 28). Hemodynamics and gas exchange were followed for 240 min post burn in four groups: No Burn, Burn-Control, Burn-U74 (10 mg.Kg-1 U74389G), No Burn-U74 (10 mg.Kg-1 U74389G).

RESULTS

Scald resulted in early pulmonary injury as measured by increased pulmonary vascular resistance in the pooled Burn group compared with the No Burn groups (942 +/- 358 vs 605 +/- 255 dynes.sec-1.cm-5 respectively, P < 0.05). These pulmonary changes were associated with alveolar sequestration of leukocytes (4.8 +/- 2.9 vs 17.7 +/- 6.0 cells x 10(9).L-1, P < 0.05) in the No Burn and Burn groups respectively. Histological evidence of decreased neutrophil sequestration after scald injury was present in U74 treated animals (3+ vs 2+, P < 0.05 in the Burn and No Burn groups respectively and 2+ vs 2+, P > 0.05 in the Burn-U74 and No Burn-U74 groups respectively) although bronchial alveolar lavage still demonstrated neutrophil sequestration (5.3 +/- 2.5 vs 12.2 +/- 3.3 cell 10(9).L-1, P < 0.05 in No Burn-U74 and Burn-U74 groups respectively). Similarly, circulating white blood cells were increased in the Burn group but not Burn-U74 group four hours post burn. The increase in pulmonary vascular resistance after burn was not altered by administration of U74.

CONCLUSIONS

Systemic burn results in early pulmonary vascular changes associated with leukocyte sequestration. After scald injury administration of lazaroids (U744389G) did not lessen pulmonary vascular resistance changes but did reduce neutrophil sequestration.

Twice-daily compared with once-daily thoracic radiotherapy in limited small-cell lung cancer treated concurrently with cisplatin and etoposide

BACKGROUND

For small-cell lung cancer confined to one hemithorax (limited small-cell lung cancer), thoracic radiotherapy improves survival, but the best ways of integrating chemotherapy and thoracic radiotherapy remain unsettled. Twice-daily accelerated thoracic radiotherapy has potential advantages over once-daily radiotherapy.

METHODS

We studied 417 patients with limited small-cell lung cancer. All the patients received four 21-day cycles of cisplatin plus etoposide. We randomly assigned these patients to receive a total of 45 Gy of concurrent thoracic radiotherapy, given either twice daily over a three-week period or once daily over a period of five weeks.

RESULTS

Twice-daily treatment beginning with the first cycle of chemotherapy significantly improved survival as compared with concurrent once-daily radiotherapy (P=0.04 by the log-rank test). After a median follow-up of almost 8 years, the median survival was 19 months for the once-daily group and 23 months for the twice-daily group. The survival rates for patients receiving once-daily radiotherapy were 41 percent at two years and 16 percent at five years. For patients receiving twice-daily radiotherapy, the survival rates were 47 percent at two years and 26 percent at five years. Grade 3 esophagitis was significantly more frequent with twice-daily thoracic radiotherapy, occurring in 27 percent of patients, as compared with 11 percent in the once-daily group (P<0.001).

CONCLUSIONS

Four cycles of cisplatin plus etoposide and a course of radiotherapy (45 Gy, given either once or twice daily) beginning with cycle 1 of the chemotherapy resulted in overall two- and five-year survival rates of 44 percent and 23 percent, a considerable improvement in survival rates over previous results in patients with limited small-cell lung cancer.

Prevention of recurrent cerebral ischemic events in patients with patent foramen ovale and cryptogenic strokes or transient ischemic attacks

BACKGROUND

Patent foramen ovale (PFO) is found in up to 50% of patients less than 55 years of age who have had a stroke. Therapeutic options include no therapy, antiplatelet therapy, warfarin and surgical closure of the PFO.

OBJECTIVES

To determine the relative and attributable risks of PFO for recurrent cerebral ischemic events in young patients with stroke or transient ischemic attacks. The predictors of recurrent cerebral ischemic events and the effects of different therapies on recurrence rates were sought.

DESIGN

Follow-up of a retrospective cohort of patients with cryptogenic stroke or transient ischemic attacks identified from an echocardiography database.

SETTING

University-based regional neurology referral centre.

PATIENTS

Consecutive group of 90 patients less than 60 years of age who underwent transesophageal echocardiography following a cryptogenic transient ischemic attack (TIA) or stroke (cerebrovascular accident [CVA]) between 1991 and 1997.

INTERVENTIONS

Structured telephone interviews and chart reviews.

RESULTS

Fifty-two patients had a PFO, and 38 patients did not have a PFO. During a mean follow-up of 46 months, 19 recurrent cerebral ischemic events (12 TIA and seven CVA) occurred in 14 patients with PFO, and eight recurrent events (three TIA and five CVA) occurred in six patients without PFO. The recurrence rates were 12% and 5%/patient/year in the PFO and control groups, respectively, for a crude recurrence rate ratio of 2.39 (95% CI 1.01 to 6.32, P < 0.03). The attributable risk of PFO in recurrent neurological events was 7%/patient/year. In a Cox regression model, predictors of recurrent neurological events were presence of PFO (hazard ratio 5.27, 95% CI 1.58 to 17.6, P < 0.007), history of migraine (hazard ratio 4.54, 95% CI 1.11 to 18.52, P < 0.035), hypertension requiring therapy (hazard ratio 3.5, 95% CI 1.33 to 9.01, P < 0.01), and antiplatelet or no therapy instead of warfarin therapy (hazard ratio 2.88, 95% CI 1.11 to 8.7, P < 0.04). Fourteen patients underwent surgical closure of PFO; there were no neurological recurrences during a mean follow-up of 43 months (crude incidence rate difference 12%/patient/year, 95% CI 6.6 to 17.9, P < 0.02).

CONCLUSIONS

Patients with PFO had a significantly higher rate of recurrent cerebral ischemic events than those without PFO. Surgical PFO closure prevented any recurrences during a mean follow-up of 43 months. Warfarin was better than antiplatelet therapy or no therapy in preventing recurrences.

The probability of blindness from open-angle glaucoma

OBJECTIVE

This study aimed to determine the probability of a patient developing legal blindness in either one or both eyes from newly diagnosed and treated open-angle glaucoma (OAG) after starting medical or surgical therapy or both.

DESIGN

The study design was a retrospective, community-based descriptive study.

PARTICIPANTS

Two hundred ninety-five residents of Olmsted County, Minnesota, newly diagnosed with, and treated for, OAG between 1965 and 1980 with a mean follow-up of 15 years (standard deviation +/- 8 years) participated.

INTERVENTION

Kaplan-Meier cumulative probability of blindness was estimated for patients treated and followed for OAG.

MAIN OUTCOME MEASURES

Legal blindness, defined as a corrected visual acuity of 20/200 or worse, and/or visual field constricted to 20 degrees or less in its widest diameter with the Goldmann 1114e test object or its equivalent on automated perimetry, secondary to glaucomatous loss, was measured.

RESULTS

At 20-years' follow-up, the Kaplan-Meier cumulative probability of glaucoma-related blindness in at least one eye was estimated to be 27% (95% confidence interval, 20%-33%), and for both eyes, it was estimated to be 9% (95% confidence interval, 5%-14%). At the time of diagnosis, 15 patients were blind in at least 1 eye from OAG.

CONCLUSION

A retrospective study of a white population determined that the risk of blindness from newly diagnosed and treated OAG may be considerable.