HER-2/neu protein-receptor-positive breast carcinoma: an immunologic perspective.

Immunotherapy using a monoclonal antibody against the human epidermal growth factor receptor 2 protein, HER-2/neu, has proven to be clinically efficacious in about one-half of breast cancer patients who exhibit strong (3+) plasmalemmal immunoreactivity for this protein. The tumoricidal effect of this antibody relies in part upon antibody-dependent cell-mediated cytotoxicity. This report provides observations on certain factors or circumstances which could have an impact on this aspect of the therapeutic approach. These include: (1) concurrent medications; (2) the composition (immunophenotype) of peritumoral lymphocytes and the generally limited numbers of intratumoral T-lymphocytes/natural killer (NK) cells, monocytes, and neutrophilic granulocytes; (3) the presence of circulating HER-2/neu antigens which might bind the exogenous antibody and lead to immune complex formation; (4) the variable co-expression in the tumor of cytokines known to downregulate NK cell function (ie, transforming growth factor-beta1 [TGF-beta1] and platelet-derived growth factor [PDGF]-AB); and (5) the tumoral and/or stromal immunoreactivity for angiotensin-converting enzyme, which forms a part of one of the pathways for the activation of latent TGF-beta1 and for the biosynthesis of PDGF-AB. These observations provide an immunologic perspective for the use of monoclonal antibody therapy in HER-2/neu protein-receptor-positive breast carcinoma and suggest a role for the clinical laboratory in identifying potential avenues for additional manipulations of the immune system in individual cases in order to enhance the therapeutic response.

Plasma concentrations following single doses of morphine sulfate in oral solution and rectal suppository.

Plasma concentrations of morphine and morphine-3-glucuronide (morphine's major metabolite) were determined following single 10-mg doses of morphine sulfate in oral solution and rectal suppository. Ten patients with pain secondary to cancer were given a single 10-mg dose of oral morphine sulfate in an oral solution or rectal suppository on sequential days. Blood samples were collected at time zero and periodically for 4.5 hours after administration. Plasma concentrations of morphine and morphine-3-glucuronide were determined using liquid chromatography with electrochemical detection. Higher mean concentrations of morphine were achieved with the rectal suppository than with the oral solution at all time points, and the overall mean plasma morphine concentration for the entire 4.5-hour period was significantly higher for the rectal suppository than for the oral solution. There were no significant differences between dosage forms in mean morphine-3-glucuronide concentrations at individual time points or over the entire period. A single dose of morphine sulfate in a rectal suppository was better absorbed than in an oral solution. Further studies are needed to compare the clinical efficacy of these dosage forms under steady-state conditions.

Double-blind crossover trial of droperidol, metoclopramide, and prochlorperazine as antiemetics in cisplatin therapy.

Droperidol, metoclopramide, and prochlorperazine were compared in a double-blind crossover trial to determine their relative effectiveness in preventing and controlling the nausea and vomiting caused by cisplatin-containing chemotherapy. Twenty-five patients receiving cisplatin-containing chemotherapy for various malignancies were entered into this trial with 14 patients completing the three-drug randomization sequence. This was the patient's first exposure to cisplatin. Each antiemetic was administered in a diluted 50 ml i.v. injection over 15 minutes beginning 0.5 hour before cisplatin and 1.5, 3.5, 5.5, and 8.5 hours after cisplatin. Dosages of antiemetics for doses of cisplatin greater than or equal to 100 mg/sq m were droperidol 2.5 mg, metoclopramide 2 mg/kg, or prochlorperazine 5 mg in each infusion. For doses of cisplatin less than 100 mg/sq m, the dosages were droperidol 2.5 mg for the first two doses and 1.25 mg for subsequent doses, metoclopramide 1 mg/kg, or prochlorperazine 5 mg for each dose. The median number of emetic episodes for the first 24 hours were as follows: droperidol 3.2; metoclopramide 1.8; prochlorperazine 3.7. There was a significant difference in number of emetic episodes demonstrating antiemetic superiority of metoclopramide over both droperidol and prochlorperazine. For these 14 patients completing the trial, eight preferred metoclopramide, two preferred prochlorperazine, one preferred droperidol, and three had no preference. At the doses used in this study, the antiemetic efficacy of metoclopramide was superior to either droperidol or prochlorperazine.