Hugo Rainer

Mitoxantrone for the treatment of advanced breast cancer: Single-agent therapy in previously untreated patients

Mitoxantrone (dihydroxyanthracenedione) is a substituted anthraquinone with a similar spectrum of activity to adriamycin in experimental tumours. One hundred and thirty-four patients with advanced breast cancer and no prior chemotherapy for advanced disease were treated with mitoxantrone (14 mg/m2 i.v. q 3 weeks), of whom 99 are presently evaluable for response and all for toxicity. Six patients achieved a complete response and 29 a partial response, the overall response rate being 35% (95% confidence limits, 25-45%). Median time to treatment failure was greater than 46 weeks. Mitoxantrone was well tolerated, myelosuppression being the dose-limiting toxicity. The most frequent nonhaematological toxicities were nausea and vomiting (40%), but these were rarely severe. Total alopecia occurred in only 6 patients. Four patients developed clinically significant evidence of cardiotoxicity after cumulative mitoxantrone doses of 174-256 mg/m2. Mitoxantrone offers comparable efficacy and less acute toxicity than the most active currently available single agents in advanced breast cancer.

Complete remission of metastasised clear cell sarcoma of tendons and aponeuroses

Clear cell sarcoma of tendons and aponeuroses is a rare disorder which originates from migrated neural crest cells. It tends to local recurrences and dissemination and the prognosis has to be considered as poor. Based on a small series of patients, a wide surgical excision of the primary tumour or amputation are the therapies of choice. Radiotherapy might be of some value as an adjuvant treatment but radiotherapy and chemotherapy are of little value in the treatment of the advanced disease. Because of the lack of treatment alternatives we treated a 40-year-old female patient with disseminated clear cell sarcoma with interferon-alpha 2b (IFN-alpha 2b) perilesionally after several courses of systemic chemotherapy and radiotherapy had failed. After 4 months of therapy the patient came into a complete pathological remission which lasted for 17 months. A relapse of round cell sarcoma on both tumour sites was then noted. This outcome shows that IFN-alpha 2b was able to induce a complete remission in clear cell sarcoma and might have altered the natural course of the disease. IFN-alpha should be studied as adjuvant therapy after surgery of primary clear cell sarcoma and as a first-line palliative treatment in disseminated disease.

Transcription and activity of 5-fluorouracil converting enzymes in fluoropyrimidine resistance in colon cancer in vitro

Cellular resistance to 5-fluorouracil (5-FU) is not completely understood. Since 5-FU shares the pyrimidine pathway with the physiological pyrimidines, we investigated the relationship between fluoropyrimidine metabolism, nucleic acid uptake and cytotoxicity of 5-FU in eight colon tumour cell lines including 5-FU-resistant subclones. The cytotoxicity of 5-FU was increased up to 423-fold when the anabolites 5-fluorouridine (FUrd), 5-fluorodeoxyuridine (FdUrd), and 5-fluorodeoxyuridine monophosphate (FdUMP) were compared with the parent drug in vitro. The enzymes uridine phosphorylase and thymidine phosphorylase were predictive for the cytotoxicity of 5-FU in 5/7 cell lines. Inhibition of uridine phosphorylase and thymidine phosphorylase by antisense strategies effectively antagonised 5-FU, abolishing 84% and 79% of its toxicity. The importance of thymidine phosphorylase was supported by a highly restricted enzyme activity in 5-FU-resistant cells. In 5-FU naive cells, a stimulating effect of 5-FU on thymidylate synthase mRNA and ribonucleotide reductase mRNA expression was observed. In these cells, antisense oligonucleotides to ribonucleotide reductase significantly reduced cell growth. Downregulation of ribonucleotide reductase mRNA in 5-FU-resistant subclones suggests different mechanisms in primary and secondary resistance to 5-FU. Most of the intracellular 5-FU was selectively incorporated into RNA (range: 45-91%) and generally spared DNA (range: 0.2-11%). In synthesising our data, we conclude that drug resistance could be overwhelmed through bypassing limiting steps in the activation of 5-FU. In the majority of colonic tumours, the activity of uridine phosphorylase and thymidine phosphorylase may have prognostic relevance for the cytotoxicity of 5-FU in vitro.

Activation of endothelium by immunotherapy with interleukin-2 in patients with malignant disorders

Treatment with intravenous recombinant human interleukin‐2 (rh IL‐2) is frequently accompanied by the capillary leak syndrome and disturbances of the coagulation system. Although the exact mechanisms are still not fully understood, the involvement of the endothelium is proven. This investigation aimed to elucidate more precisely the role of the endothelium in the generation of IL‐2‐based side‐effects. In nine tumour patients receiving intravenous rh IL‐2, parameters characterizing endothelial cell activation as well as activation of the coagulation system were evaluated. A significant increase of the circulating endothelial leucocyte adhesion molecule‐1 (cELAM‐1) and the vasoconstrictor peptide endothelin‐1 (ET‐1) was observed (P < 0.05), indicating activation of endothelial cells. The simultaneous increase of tissue‐plasminogen activator and plasminogen activator inhibitor type‐1 during therapy (P < 0.05) corroborated this observation. A decrease in platelet count parallelled by an increase of fibrin degradation products, the prolongation of partial thromboplastin time, and the decrease of fibrinogen (P < 0.05) suggested the development of disseminated intravascular coagulation (DIC), induced by activated endothelium and intensified by transient hepatic failure. We concluded that activation of the endothelium mediated by IL‐2 was accompanied by a loss of endothelial integrity and capillary leak. The activated endothelium can trigger DIC via activation of the coagulation cascade. The increased ET‐1 might act as an endogenous counter‐regulator of the disadvantageous haemodynamic side‐effects induced by IL‐2.

Determination of methotrexate in human urine at nanomolar levels by high-performance liquid chromatography with column switching

An high-performance liquid chromatographic method with column switching for the detection of less than 4 ng of methotrexate in the urine of oncologic nurses is described. Urine samples were purified by solid-phase extraction on silica-bonded phenyl columns, eluting impurities with ethyl acetate. After elution from the column, the analyte was concentrated ten-fold, evaporating the solvent. On a strong anion-exchange column (Nucleosil 100 SB), methotrexate was separated from the remaining interfering substances, was then switched to a reversed-phase column (LiChrospher 100 RP-18e), and finally eluted by a linear gradient in a solvent system consisting of ammonium formate buffer (pH 2.7) and acetonitrile. Absorbance was monitored at 310 nm. This method has proved to be suitable for detecting traces of methotrexate in urine in order to individualize risks and to reduce further the occupational safety hazard for hospital personnel.

The Effect of Adjuvant Chemotherapy in Gastric Carcinoma Is Dependent on Tumor Histology: 5- Year Results of a Prospective Randomized Trial

Gastric carcinoma is decreasing in incidence in Western Europe and the United States. However, this disease is still a major cause of cancer death [1]. Extended surgical procedures over the past 20 years have not profoundly altered the poor outcome of patients with gastric carcinoma [2]. This fact indicates that surgery alone may not be enough to control the disease. In 1978 we began a prospective randomized, one-center trial to determine, whether postoperative treatment with mitomycin C (MMC), 5-fluorouracil (5-FU), and cytosine-arabinoside (Ara-C) given for three courses could substantially improve the overall survival of patients treated by curative resection for gastric carcinoma. The regimen employed had been shown to be the most effective chemotherapy combination at the time the study started [3]. At a median follow-up of 5 years we found no significant effect of adjuvant chemotherapy on overall survival compared with an untreated control group. However, in a retrospective subgroup analysis we observed a significant improvement in the overall survival of patients with the intestinal tumor type, but no effect in patients with mucocellular carcinoma. We therefore believe that there is a selective effect of adjuvant chemotherapy in patients with gastric carcinoma with intestinal type of tumors.

Escalating dose regimen of intraperitoneal mitoxantrone: phase I study ― clinical and pharmacokinetic evaluation

Mitoxantrone, a recent anthracenedione derivative, is a potentially useful drug for direct intraperitoneal (i.p.) application because of its high tissue binding and therapeutic index. We have carried out studies to establish maximum tolerated doses as well as pharmacokinetic studies with i.p. mitoxantrone in 21 patients (5 male, 16 female) with gastrointestinal (9), ovarian (6), unknown (2) and other (4) primary cancers and peritoneal carcinomatosis. Increasing doses (10-40 mg/m2) were given i.p. every 4 weeks. Five partial remissions (2-8+ months) and 7 stable disease courses (2-6+ months) were achieved. A reduction or disappearance of ascites was seen in an additional 3 patients. Severe toxicity (leucopenia) was observed in 4 patients only after 35 and 40 mg/m2 i.p. Pharmacokinetic analysis using high performance liquid chromatography yielded the following data: The mean ratio of area under curve peritoneal fluid to plasma was 1109. The peritoneal clearance rate was 680 ml/min and the mean disappearance half life was 13.1 h. Mean urinary excretion within 24 h was 0.42% of the i.p. dose. These data indicate that mitoxantrone is sequestered in the intraperitoneal tissue compartment and only slowly released. Based on the outcome of this phase I study we recommend phase II studies at a dose of 30 mg/m2 i.p., repeated every 3-4 weeks.

Mitoxantrone as first-line chemotherapy in advanced breast cancer: results of a collaborative European study

SummaryMitoxantrone (Novantrone®; dihydroxyanthracenedione) is a substituted anthraquinone with a spectrum of activity similar to doxorubicin in experimental tumors.One hundred and seventy three patients with advanced breast cancer and no prior cytotoxic therapy for advanced disease entered a phase II study of mitoxantrone, 14 mg/m2 i.v. repeated every 3 weeks. At the time of this analysis 116 patients were evaluable. Eight patients achieved a complete response and 27 a partial response, the overall response rate being 30% (95% confidence limits: 22–39%). The median time until response was recorded was 15 weeks. The median duration of response was 74+ weeks and the median time to progression or death for all 116 patients was 22+ weeks.Mitoxantrone was well tolerated with myelosuppression as the dose-limiting toxicity. The most frequent non-haematological toxicities were nausea and vomiting (65%) but they were rarely severe. Total alopecia occurred in only 6% of the patients. Four patients developed clinically significant evidence of cardiotoxicity after cumulative mitoxantrone doses of 174–256 mg/m2.Thus, mitoxantrone offers comparable efficacy and less acute toxicity than the most active single agents currently available in the treatment of advanced breast cancer.

Cutaneous side effects in breast cancer patients treated with cytostatic polychemotherapy and rh GM-CSF: immune phenomena or drug toxicity?

SummaryThe application of recombinant colony stimulating factors for chemotherapy induced granulocytopenia is becoming common in clinical oncology. Here we report on localized cutaneous side effects after subcutaneous administration of recombinant human granulocyte-macrophage colony-stimulating factor (rh GM-CSF) in 11 patients with breast cancer receiving cytostatic treatment. Seven patients suffering from inflammatory breast cancer received cytostatic chemotherapy with mitoxantrone/cyclophosphamide, whereas four patients suffering from noninflammatory breast cancer received high-dose epirubicin/cyclophosphamide, respectively. rh GM-CSF was applicated subcutaneously in a dose of 5 µg/kg/d for at least ten days. In all patients, sharply demarked, maculous itching and burning erythemas restricted to the injection sites occured after three to four injections of rh GM-CSF. These eruptions cleared within 2 to 3 weeks, but reappeared after reexposure to rh GM-CSF. In contrast to previous sporadic reports, no generalized erythemas were observed. Because of this unexpected and subjectively intolerable side effect, rh GM-CSF administration had to be interrupted in all patients. Histopathological findings revealed skin infiltration with lymphocytes, monocytes/macrophages, neutrophils, and occasionally eosinophils, respectively. Since GM-CSF is known to alter immune functions, it seems likely that the eruptions were at least in part due to local immune reactions.

INSTABILITY OF THE ANTICANCER AGENT ETOPOSIDE UNDER IN VITRO CULTURE CONDITIONS

SummaryDegradation of etoposide is rapid under in vitro culture conditions. At pH 7.4 and 37°C, the isomerisation of trans-etoposide to the inactive compound cis-etoposide has a half-life of 2 days in Dulbeccos modified Eagles medium and results in the loss of 90% of the active drug within 1 week. As a consequence, prolonged incubations with etoposide in in vitro assays may lead to erroneous interpretations ignoring the real in vitro situation. The degradation is not influenced by organic compounds such as bovine serum albumin or amino acids but depends strongly on the pH value and, to a lesser degree, on the ionic strength of the medium. Therefore, we propose a mathematical correction based on the pH value so as to obtain the real exposure of cells to trans-etoposide during in vitro assays.