Reduction of beta-endorphin content in the rat pituitary after dehydration and adrenalectomy

Both dehydration and adrenalectomy of rats caused a significant reduction of immunoreactive beta-endorphin in the pituitary gland. Beta-Endorphin in hypothalamus, however, was not altered in either dehydrated or adrenalectomized rats.

Multicenter phase II study to evaluate a 28-day regimen of oral fluorouracil plus eniluracil in the treatment of patients with previously untreated metastatic colorectal cancer

PURPOSE

To determine the efficacy of fluorouracil (5-FU) plus eniluracil when administered to patients with previously untreated metastatic colorectal cancer.

PATIENTS AND METHODS

In this single-arm phase II study, patients with previously untreated metastatic colorectal cancer received oral eniluracil plus 5-FU (10:1 dose ratio), at 5-FU doses of 1.00 mg/m(2) or 1.15 mg/m(2) twice daily (every 12 hours) for 28 consecutive days repeated every 5 weeks (one cycle). Treatment continued until there was documented disease progression or unacceptable toxicity.

RESULTS

Thirty and 25 patients were enrolled at a starting dose of 1.00 mg/m(2) and 1.15 mg/m(2), respectively. Fourteen (25%) of 55 patients (95% confidence interval, 15% to 39%) had a partial response, and 20 patients (36%) had stable disease. The median durations of the partial responses and stable disease were 23.9 weeks (range, 12.3 to 52.1+ weeks) and 24.1 weeks (range, 17.1 to 55.6+ weeks), respectively. The median durations of progression-free and overall survival were 22.6 weeks (range, 21.0 to 29.0 weeks) and 59 weeks (range, 4 to 84+ weeks), respectively. The response rate in the 1.15 mg/m(2)-dose group was similar to the 1.00 mg/m(2)-dose group (28% v 23%, respectively). Severe (grade 3/4) nonhematologic treatment-related toxicity included diarrhea (nine patients), nausea/vomiting (one patient each), mucositis (two patients), and anorexia (one patient). Severe hematologic toxicities were rare. At the 1.15 mg/m(2)-dose level, two patients exhibited grade 3 granulocytopenia, and two patients had grade 3 anemia.

CONCLUSION

The response rate with oral 5-FU plus eniluracil is comparable with that observed with infusional 5-FU or bolus 5-FU and leucovorin. The toxicity profile of this oral regimen is acceptable for use in an outpatient home-based setting.

A phase II study of 9-aminocamptothecin in patients with refractory breast cancer

We evaluated 9-aminocamptothecin (9-AC) in patients with metastatic or locally recurrent breast cancer who were no longer responsive to standard therapy. Patients were treated with 9-AC with a 72-hr continuous infusion given at a dose of 45 micrograms/m2/hr every 2 weeks. Granulocyte colony-stimulating factor 5 micrograms/kg was given subcutaneously for 7-10 days after completion of the treatment. Eighteen patients were treated, with all patients assessable for toxicity and 15 patients assessable for response. There were two partial responses seen in the 15 patients lasting 3.5 and 5 months, respectively. The major toxicity seen was myelosuppression, with 12 patients having grade 3 or greater granulocytopenia with four episodes of significant infectious complications. In addition, significant thrombocytopenia was seen in 14 patients. The other complications commonly seen were nausea and vomiting and alopecia. 9-AC given as a 3-day continuous infusion has limited activity in previously treated metastatic and locally recurrent breast cancer.

Phase II trial to topotecan in hepatocellular carcinoma: a Southwest Oncology Group study

Hepatocellular carcinoma remains a highly chemoresistant neoplasm. In this study of the topoisomerase I inhibitor topotecan a response rate of 13.9% (95% confidence interval 4.7%-29.5%) was obtained utilizing a five consecutive day bolus infusion schedule. There were no complete responses and the median survival was only eight months. Furthermore, treatment with topotecan produced significant toxicity with two-thirds of patients experiencing life-threatening (grade 4) neutropenia. When used in this dose and schedule, topotecan does not appear to be effective for patients with advanced hepatocellular carcinoma.

Phase II evaluation of ifosfamide/mesna in metastatic prostate cancer. A Southwest Oncology Group study

The combination of ifosfamide and mesna was evaluated in a phase II trial in the treatment of metastatic prostate cancer. Two separate groups of patients were to be evaluated: patients with no prior hormonal therapy and hormonally refractory patients. Patients were treated with ifosfamide 1.5 g/M2, and mesna at 30% of the ifosfamide dose was administered immediately before and 4 and 8 h after ifosfamide treatment. Both drugs were given i.v. daily for 5 days every 21 days. Response was assessed every 6 weeks. Of 29 eligible and evaluable patients with hormonally refractory disease, there were two partial responders for a response rate of 7% (95% confidence interval, of 0.1-23%). Of nine eligible patients with no prior hormone treatment, there was one partial response, for a response rate of 11% (95% confidence interval, 0.3-48%). Unfortunately, the target accrual goal for this arm of the study was never achieved. The most common toxicities were myelosuppression and neurologic toxicity. These drugs do not warrant further evaluation in the disease.

Vinorelbine (Navelbine)/carboplatin combination therapy: dose intensification with granulocyte colony-stimulating factor

Treatment with platinum agents or the new vinca alkaloid vinorelbine (Navelbine; Burroughs Wellcome Co, Research Triangle Park, NC; Pierre Fabre Médicament, Paris, France) results in prolonged survival in patients with advanced non-small cell lung cancer (NSCLC). To determine whether a unique combination of these agents might enhance activity against NSCLC, a combination chemotherapy regimen consisting of intravenous carboplatin, administered on days 1 and 29, and intravenous vinorelbine, given once weekly, was evaluated. Because the dose-limiting toxicity of both agents is myelosuppression, an additional study goal was to assess the ability of granulocyte colony-stimulating factor to alleviate hematologic toxicity and allow on-time, full-dose vinorelbine therapy. To this end, a phase I/II study was begun. Phase I of the study included 22 patients (15 men and seven women) with a median age of 63 years (age range, 39 to 77 years) who had stage IV NSCLC and no prior chemotherapy. Phase I consisted of 28-day cycles in which intravenous carboplatin was administered at an area under the curve of 7 by the Calvert formula, dose range 350 to 450 mg/m2, and intravenous vinorelbine was administered weekly. Granulocyte colony-stimulating factor was administered if dose-limiting neutropenia developed. Four cohorts of patients were studied, ranging from those who received no vinorelbine to those who received drug doses of up to 30 mg/m2. Patients were able to tolerate the highest dose of vinorelbine, but the majority required granulocyte colony-stimulating factor support to do so. No novel toxicities were observed in patients treated with the combination of carboplatin and vinorelbine.(ABSTRACT TRUNCATED AT 250 WORDS)

Tamoxifen versus high-dose oral medroxyprogesterone acetate as initial endocrine therapy for patients with metastatic breast cancer: a Piedmont Oncology Association study

PURPOSE

To determine in a prospective randomized trial whether high-dose orally administered medroxy-progesterone acetate (MPA) was superior to tamoxifen in patients with recurrent or metastatic breast cancer who had received no prior endocrine therapy in either the adjuvant or advanced setting.

PATIENTS AND METHODS

Patients initially received either tamoxifen 20 mg/d orally or MPA 1 g/d orally. At the time of disease progression, patients were crossed over to the other regimen. Eligibility required patients to be age > or = 18 years, performance status 0 to 3, and estrogen receptor (ER)- or progesterone receptor (PR)-positive or unknown.

RESULTS

One hundred eighty-two eligible patients were entered and 166 were assessable for response. Complete plus partial response rates for tamoxifen and MPA were 17% and 34%, respectively (P = .01). Patients with bone metastases had a significantly higher partial response rate with MPA compared with tamoxifen (33% v 13%). Median time to treatment failure was 5.5 months for tamoxifen and 6.3 months for MPA (P = .48). The median survival duration was 24 months for tamoxifen and 33 months for MPA (P = .09). Multivariate analysis showed that treatment significantly influenced response rate, but not time to treatment failure or survival. After treatment failure following MPA, six of 42 patients (14%) treated with tamoxifen responded, compared with six of 49 (12%) treated with MPA following tamoxifen. Both agents were associated with minimal toxicity, but 35% of patients on MPA gained more than 20 lb as opposed to only 2% on tamoxifen.

CONCLUSION

In this trial, initial treatment with MPA of endocrine-naive metastatic breast cancer patients was associated with a significantly higher response rate but not with improvement in time to treatment failure or survival, when compared with initial treatment with tamoxifen. Further randomized trials in patients with bone metastases are warranted to determine if high-dose progestin therapy is superior to tamoxifen in these patients.

Lung cancer in the elderly

Half of all lung cancers occur in persons aged 65 years and older. The symptoms of lung cancer in the elderly may be nonspecific and misleading. Age trends in incidence, histologic subtype, and stage suggest that selective screening of older persons for lung cancer should be studied. Recent data reveal that the mortality risk for lung cancer surgery in selected elderly patients is comparable to that for younger patients. Age alone should not deny older lung cancer patients optimal evaluation, treatment, and care.

Age trends of lung cancer stage at diagnosis. Implications for lung cancer screening in the elderly

Lung cancer increases in incidence with increasing age and is the leading cause of cancer death in the United States. While mass screening for lung cancer is not indicated, selective screening of high-risk target groups may be beneficial. We tested the hypothesis that lung cancer is initially seen at a less advanced stage with increasing age using incidence cases (N = 22,874) from the Centralized Cancer Patient Data System. The percent of lung cancer patients with local stage disease increased from 15.3% of those aged 54 years or younger, to 19.2% of those aged 55 to 64 years, to 21.9% of those aged 65 to 74 years, and to 25.4% of those aged 75 years or older. The percent with distant stage decreased from 48.7%, to 44.5%, to 40.3%, and to 36.7% for the same age groups, respectively. These age-stage trends persisted in subgroup analysis by sex, race, and histological subtype. Furthermore, analysis of 6332 patients who underwent surgical staging showed a greater likelihood of local stage disease with increasing age. Thus, compared with the young, the group aged 65 years or older is at a greater risk for lung cancer and has a higher proportion of lung cancer initially seen at local stage. The efficacy of selective screening for lung cancer in this target group warrants additional study.

Potentiation of opiate action in neuroblastoma N18TG2 cells by lipid incorporation

The effect of cerebroside sulfate, phosphatidylserine, and other phospholipids on opiate receptor function in neuroblastoma N18TG2 cells was studied by incorporation of lipids into the membrane bilayer of viable cells. A concentration- and time-dependent incorporation of sulfatide by N18TG2 cells was observed. The incorporated lipid was not metabolized during the incubation period of up to 48 hr at 37 degrees. Optimal conditions for lipid incorporation were determined to be 4 days after the cell seeding and in 1% fetal calf serum. The incorporated lipid was established to be associated with the plasma membrane fraction of the crude cell homogenate. Furthermore, increases in Vmax but not Km values of the adenylate cyclase for Mg2+, ATP, and prostaglandin E1 were observed in neuroblastoma N18TG2 cells exposed to cerebroside sulfate for 4--6 hr. The incorporation of cerebroside sulfate or phosphatidylserine by N18TG2 cells did not increase the number of opiate binding sites in this cell line as determined by [3H]naloxone, [3H]etorphine, or 3H-labeled D-Ala2-Met5-enkephalinamide binding. Although there was an increase in the affinity of [3H]naloxone binding, linear correlation between the amount of cerebroside sulfate incorporated and the quantity of binding increase was not observed. However, augmentation of both the potencies and the efficacies (maximal inhibitory level) of morphine and enkephalin to regulate adenylate cyclase activity was observed after sulfatide incorporation. At the maximal concentration of cerebroside sulfate used (67 microM) the opiate receptor activity in N18TG2 cells approached that of NG108-15 cells. Identical treatment of N18TG2 cells with cerebroside or psychosine sulfate did not produce any potentiation of the opiate inhibition of adenylate cyclase. Of all of the phospholipids tested--phosphatidylserine, phosphatidylinositol, and phosphatidylcholine--only phosphatidylcholine produced a potentiation of the opiate effect. Both synthetic dipalmitoyl phosphatidylcholine or brain phosphatidylcholine could elicit the potentiation.