Phase II study of paclitaxel and valspodar (PSC 833) in refractory ovarian carcinoma: a gynecologic oncology group study.

PURPOSE: A phase II study was conducted to determine the efficacy of paclitaxel and valspodar (PSC 833) in patients with advanced epithelial ovarian cancer. Valspodar, a nonimmunosuppressive cyclosporine D analogue that reverses P-glycoprotein-mediated multidrug resistance, in combination with paclitaxel might be active in paclitaxel-resistant and refractory ovarian cancer. PATIENTS AND METHODS: Patients received valspodar 5 mg/kg orally qid x 12 doses. Paclitaxel (70 mg/m(2) intravenously for 3 hours) was administered on day 2, 2 hours after the fifth or sixth dose of valspodar. This treatment was repeated every 21 days. One blood sample was collected before the sixth dose of valspodar for the first three cycles to evaluate valspodar trough concentration. Tumor tissue was obtained from patients for immunohistochemical staining of P-glycoprotein. RESULTS: Of 60 patients entered, 58 were assessable for response. There were five partial responses (8.6%; 90% confidence interval [CI], 3.8 to 20.0; median duration of response, 5.0 months [range, 1.9 to 10.5 months]). Median progression-free survival was 1.5 months (90% CI, 1.4 to 2.4). Grade 3 or 4 toxicities observed were neutropenia, anemia, nausea and vomiting, peripheral neuropathy, and cerebellar ataxia. The trough concentrations of valspodar were > or = 1,000 ng/mL in all but two of 40 patients in the first cycle. Immunohistochemical staining for P-glycoprotein was positive for one of two responding patients. CONCLUSION: Valspodar in combination with paclitaxel has limited activity in patients with paclitaxel-resistant ovarian carcinoma. An international randomized clinical trial of paclitaxel and carboplatin with or without valspodar as first-line therapy in advanced ovarian cancer is underway.     

A phase I study of irinotecan in pediatric patients: a pediatric oncology group study.

A Phase I trial of irinotecan was performed to determine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), and the incidence and severity of other toxicities in children with refractory solid tumors. Thirty-five children received 146 courses of irinotecan administered as a 60-min i.v. infusion, daily for 5 days, every 21 days, after premedication with dexamethasone and ondansetron. Doses ranged from 30 mg/m2 to 65 mg/m2. An MTD was defined in heavily pretreated and less-heavily pretreated (i.e., two prior chemotherapy regimens, no prior bone marrow transplantation, and no radiation to the spine, skull, ribs, or pelvic bones) patients. Myelosuppression was the primary DLT in heavily pretreated patients, and diarrhea was the DLT in less-heavily pretreated patients. The MTD in the heavily pretreated patient group was 39 mg/m2, and the MTD in the less-heavily pretreated patients was 50 mg/m2. Non-dose-limiting diarrhea that was well controlled and of brief duration was observed in approximately 75% of patients. A partial response was observed in one patient with neuroblastoma, and in one patient with hepatocellular carcinoma. Stable disease (4-20 cycles) was observed in seven patients with a variety of malignancies including neuroblastoma, pineoblastoma, glioblastoma, brainstem glioma, osteosarcoma, hepatoblastoma, and a central nervous system rhabdoid tumor. In conclusion, the recommended Phase II dose of irinotecan administered as a 60-min i.v. infusion daily for 5 days, every 21 days, is 39 mg/m2 in heavily treated and 50 mg/m2 in less-heavily treated children with solid tumors.     

A phase II study of carboplatin plus gemcitabine in advanced non-small-cell lung cancer (NSCLC): a hoosier oncology group study

The purpose of this study was to evaluate the toxicity and determine the response rate, duration of remission, and survival using gemcitabine plus carboplatin in non-small cell lung cancer (NSCLC). This was a phase II study of gemcitabine and carboplatin in chemotherapy-naive patients with advanced NSCLC and Karnofsky Performance Status of at least 80. Gemcitabine was administered intravenously at 1,000 mg/m2 weekly for 3 weeks followed by 1 week rest. Carboplatin was administered immediately after gemcitabine at an area under the curve (AUC) of 5 given intravenously on day 1 of an every-4-week cycle. Seven patients were entered in the study and five were evaluable for toxicity. The median age of patients was 68 years (range, 52-72). The protocol was prematurely terminated because of severe and unexpected hematologic toxicity. Grade 3-4 thrombocytopenia was observed in four of the first five patients. These toxicities were all observed with the first course of chemotherapy. There were no objective responses seen. Median survival time was 130 days. Carboplatin plus gemcitabine was a logical combination. However, because of the severe thrombocytopenia associated with this regimen, we do not recommend this two-drug combination in the dose and schedule used in this study.     

Phase II study of etoposide (NK 171) in advanced hematological malignancies

A clinical study of a new semisynthetic podophyllotoxin etoposide (NK 171) was performed in patients with various hematological malignancies refractory to standard chemotherapies. The drug was given intravenously in a dose of 100-130 mg/m2/day for five days or orally in a dose of 130-170 mg/m2/day for five days. Out of 9 patients with non-Hodgkin's lymphoma, 2 CR and 4 PR were obtained; out of 4 acute nonlymphoblastic leukemias, 1 CR, and out of 4 chronic myerogenous leukemias 2 CR and 1 PR, were obtained. The dose limiting factor was leukopenia, and alopecia was frequent while other hematologic and gastrointestinal toxicities were mild. Etoposide (NK 171) had no clinical cross resistance to other antitumor agents, thus warranting further clinical trials, in combination chemotherapy against NHL, ANLL and CML-BC.     

A study of the decision outcomes and financial costs of multidisciplinary team meetings (MDMs) in oncology

Background:

The benefits of multidisciplinary working in oncology are now accepted as the norm and widely accepted as being pivotal to the delivery of optimal cancer care. Central to this are the multidisciplinary meetings (MDMs) and we have evaluated decision outcomes and financial costs of these.

Methods:

We reviewed the electronic patient records of 551 newly referred patients, discussed at 14 tumour site-specific MDMs for adult solid tumours and lymphoma (paediatric oncology and acute leukaemia were excluded) over a 1-month period, a total of 52 MDMs were studied. In addition, the records of a further 81 patients from 10 different MDMs were reviewed where the treating consultant had clearly recorded their opinion of how the patient should be managed and this was compared with the final MDM''s consensus view. We also costed the MDMs utilising two different methodologies.

Results:

The mean age of the 551 patients in the study was 62 years. In all, 536 (97.3%) patients were treatment naive before MDM discussion and 15 (2.7%) had prior treatment. Median time to treatment after the MDM was 16 days. In 535 (97.1%) cases, the MDM discussions were clearly documented, 16 (2.9%) were not clearly documented. In total, 319 (57.9%) patients were discussed once, and 232 (42.1%) were re-discussed (one to six occasions). In 62 (12.7%) patients, there were delays in MDM discussion, 30 (48.4%) were related to radiology, 26 (41.9%) to histopathology and 6 (9.7%) a combination of both. Adherence to the MDM management plan decision occurred 503 times (91.3%) with 48 (8.7%) deviations. In the smaller cohort of 81 patients, the consultant management plan and MDM consensus was compatible 71 (87.6%) times. On four occasions, there were major alterations in management while six were minor. The cost per month of our MDMs ranged from £2192 to £10 050 (median £5136) with total cost of £80 850 per month and the cost per new patient discussed was £415.

Conclusion:

Adherence to MDM decisions by health-care professionals occurs in the majority of patients. MDMs are costly, which may have relevance in the currently challenged health-care financial environment. There is a need to improve MDM efficiency without losing the considerable benefits associated with regular MDMs.     

A phase II study of (2'R)-4'-0-tetrahydropyranyladriamycin (THP) in patients with hematological malignancies. THP Study Group

A Phase II study of a new anthracycline, (2'R)-4'-0-tetrahydropyranyladriamycin (THP), was conducted in 162 patients with various hematological malignancies in a multi-institutional cooperative study. THP was given intravenously at a dose of either 10-30 mg/body for 3-5 consecutive days or 40-60 mg/body at 3-week intervals. Of 22 patients with AML, complete remission (CR) was observed in 2 patients and partial remission (PR) in 2. Of 18 patients with ALL, CR was observed in 5 and PR in 3. Of 68 patients with NHL, CR was observed in 11 and PR in 22. Of 8 patients with HD, CR was observed in 4 and PR in 2. One CML case showed CR and one ATL case showed PR. PR was noted in one of 2 patients with mycosis fungoides. Overall remission rate was 43.1% (CR 23 cases and PR 33 cases). The predominant toxicity was myelosuppression. Leukopenia (less than 4,000/mm3) was noted in 67 (77.6%) and thrombocytopenia (less than 10 X 10(4)/mm3) in 24 (27.0%). Nausea/vomiting and anorexia were common, and were observed in 61 (43.3%) and 65 (46.1%) cases, respectively. Hair loss and cardiotoxicity were mild and recovered quickly on discontinuation of THP. Thus, THP was found to be effective for various hematological malignancies including acute leukemia and malignant lymphoma.     

Randomized study of long-term adjuvant chemotherapy with Futraful and mitomycin C in gastric cancer. A second study (fourth report)

In view of the usefulness of long-term adjuvant chemotherapy, the Cooperative Study Group of Surgical Adjuvant Chemotherapy for Gastric Cancer adopted as a second cooperative study a randomized controlled trial including three groups; MMC alone, Futraful alone and a combination of MMC and Futraful. In the groups given Futraful alone and the combination therapy, the survival and disease-free rate were improved at five years, in patients with stage III. Moreover, the survival and disease-free rate for the group given combination therapy were higher than those for the group given Futraful alone. Also, in the groups given Futraful alone and the combination therapy, toxicities probably due to the long-term Futraful therapy were minor, without serious side effects. Therefore, a long-term combined adjuvant chemotherapy with MMC and Futraful seems to be an effective chemotherapy regimen for resectable gastric cancer. A more potent regimen and cyclic therapy may be needed to improve the result of treatment.     

Radiation oncology in a Canadian province: measures of workload and treatment complexity

Aims

A growing and aging population is associated with an increased incidence of cancer. Advances in radiotherapy technology have changed the way radiation is planned and delivered. This population-based study documented changes in workload and treatment complexity over a 10 year period in a Canadian province.

Materials and methods

We examined the population-based radiation records of a provincial Canadian cancer centre from 2000 (or from 2005 for some measures) to 2009 inclusive. We propose new measures of workload and treatment complexity currently used in our centre that can be easily adopted by other cancer centres.

Results

Workload measured by total new-to-doctor consultations increased 30% from 2000 to 2009 (3.3% annually, P = 0.0008). Total treatment commencements increased 35% over the same time (3.9% annually, P < 0.0001) but linear accelerator (linac) commencements increased at a slower rate of 2.0% annually (P = 0.0002). The rates of increase in consultations and total commencements were faster than the rates of increase in the total population, the population over age 50 years, or the incidence of cancer. Implementation of stereotactic radiosurgery and increased brachytherapy treatments explain much of the increased workload. Measures of treatment complexity including simulations per linac course and radiation computer plans per linac course increased at steady rates of 3.6% (P = 0.0019) and 3.2% (P = 0.0088) annually, respectively, but portals (fields) per linac treatment course increased exponentially after the implementation of intensity-modulated radiotherapy. The number of fractions per linac patient declined by 2.6% annually (P < 0.0001).

Conclusions

This population-based study showed that radiation oncology workload increased at faster rates than the population or incidence of cancer. Measures of treatment complexity indicate an increasing investment for each course of linac treatment, but also the adoption of hypofractionated regimens. These results indicate that radiotherapy manpower requirements cannot be based on population or cancer incidence alone if current technological trends continue.     

In vitro activity of cefpirome (HR 810) against enterococci and staphylococci.

The inhibitory activity of cefpirome (HR 810), a new cephalosporin derivative for parenteral use, was tested by agar dilution methods against Enterococcus faecalis (100 strains), Staphylococcus aureus (40 strains) and coagulase-negative staphylococcal species (60 strains) in comparison with other beta-lactam antibiotics. For E. faecalis, the cefpirome minimum inhibitory concentration (MIC) range was 2-128 micrograms/ml, with an MIC50 of 8 micrograms/ml, and an MIC90 of 64 micrograms/ml. The optimal bactericidal activity against strains with MICs of < or = 8 micrograms/ml occurred at 2-4 times the MIC, and the reduction in the initial inoculum was 99.9-99.7% after 24 h incubation at these concentrations. Mec gene-negative staphylococci (both S. aureus and coagulase-negative species) had cefpirome MICs of 0.25-2 micrograms/ml (MIC50 0.5 microgram/ml, MIC90 1 microgram/ml). Mec gene-positive strains had MICs of 0.5-128 micrograms/ml (MIC50 2 micrograms/ml, MIC90 32 micrograms/ml). Strains with borderline resistance to oxacillin which did not harbor the mec gene and which were susceptible to cefpirome maintained their susceptibility even when high-density inocula were used and after several passages in media containing the antibiotic. These studies present some potential advantages of cefpirome over other cephalosporins in the inhibitory activity against Gram-positive cocci.     

Dose escalation and pharmacokinetics of pegylated liposomal doxorubicin (Doxil) in children with solid tumors: a pediatric oncology group study.

PURPOSE: To determine the maximum tolerated dose and pharmacokinetics of Doxil in children with recurrent or refractory solid tumors. Doxil is pegylated doxorubicin. EXPERIMENTAL DESIGN: Eligible patients were children with refractory tumors who had received cumulative anthracycline doses <300 mg/m(2). Cohorts of at least three patients each received escalating doses of Doxil starting at 40 mg/m(2) at 4-week intervals. If no dose-limiting toxicity occurred, dosages were escalated by increments of 10 mg/m(2) in subsequent cohorts. Originally, Doxil was administered over 60 min, but significant infusion reactions prompted longer infusion times of 4 h. Patients also received premedication with dexamethasone, ranitidine, and diphenhydramine 24 h before infusion, with ranitidine continued 24 h after infusion. Periodic blood samples were collected and plasma doxorubicin concentrations were quantified to characterize the pharmacokinetics of Doxil. RESULTS: Between January 1997 and June 2000, 22 children ages 4-21 years with refractory tumors were treated with Doxil. Most patients had received one to five prior chemotherapy regimens, and all but five had prior radiotherapy (two had no prior therapy). Doxil was escalated to a dosage of 70 mg/m(2). At that level, dose-limiting mucositis was seen during the first cycle in two of six patients, thus defining dose-limiting toxicity, and in one additional patient during a subsequent cycle. Grade 4 neutropenia lasting less than 7 days was documented in two of six patients. The dose-limiting toxicity among two of six patients at 70 mg/m(2) was grade 3 mucositis during the first cycle of therapy. Painful desquamating dermatitis of the hands and feet, palmar-plantar erythrodysesthesia, occurred in six patients. In two of those patients, palmar-plantar erythrodysesthesia started as grade 1 and progressed to grade 2 during subsequent courses. Mean estimates of central volume of distribution, clearance, and elimination half-life were 1.45 liters/m(2), 0.03 liter/h/m(2), and 36.4 h, respectively. CONCLUSION: The maximum tolerated dose of Doxil administered every 4 weeks to pediatric patients was 60 mg/m(2). The effect of Doxil on pediatric patients with malignancies remains to be determined and should be studied in pediatric Phase II trials.     

Phase II study of SM-108 (4-carbamoylimidazolium-5-olate) in hematological malignancies

A total of 165 patients were entered into this study and 140 were evaluate for effects and 165 for toxicities. Of 39 patients with chronic myelogenous leukemia (CML) 21 achieved complete remission (CR), 6 achieved partial remission (PR) with a response rate of 69.2%. In MDS, of 11 patients with chronic myelomonocytic leukemia (CMMoL), one good partial response and 4 partial response were observed (CR + PR:45.5%); of 14 patients with RAEB, one complete response, 4 partial response (CR + PR: 35.7%); of 11 patients with RAEB in T, 3 partial response were observed (response rate: 27.3%). Of 13 patients with polycythemia vera, 4 excellent effect and 7 moderate effect (84.6%) were observed. Seven of 30 patients with acute myelocytic leukemia achieved partial response (23.3%). Mean dosages of SM-108 until remission were 400-500 mg/m2/day on CMMoL, RAEB in MDS, polycythemia vera and CML, and 600-800 mg/m2/day on RAEB in T and AML. In the analysis of adverse effects of SM-108, a subjective side effects including mainly gastrointestinal toxicities were observed in 38 cases (23.0%) of the patients : 26 patients (15.8%) showed objective side effects including liver dysfunction, but these symptoms were transient and not serious. Our study indicates that SM-108 is useful agent against MDS, especially CMMoL, RAEB, RAEB in T, polycythemia vera and CML.     

Pharmacokinetics of O(6)-benzylguanine in pediatric patients with central nervous system tumors: a pediatric oncology group study.

PURPOSE: To report the results of the first pharmacokinetic study in pediatric patients of O(6)-benzylguanine (O(6)BG), which irreversibly inactivates the DNA repair protein alkylguanine-alkyltransferase, thus enhancing the cytotoxicity of nitrosoureas. EXPERIMENTAL DESIGN: As part of a Pediatric Oncology Group Phase I study, 120 mg/m(2) of O(6)BG was administered i.v. over 1 h, before 1,3-bis(2-chloroethyl)-1-nitrosourea administration in children with recurrent or refractory brain tumors. Serial blood samples for plasma pharmacokinetic studies were obtained. Concentrations of O(6)BG and its active metabolite O(6)-benzyl-8-oxoguanine (8-oxo-O(6)BG) were measured by high-performance liquid chromatography. A pharmacokinetic model and additional first-order elimination rate constants for each compound were developed. RESULTS: O(6)BG concentration versus time data were evaluated for 25 patients. The peak concentration of O(6)BG (mean +/- SD) was 11 +/- 4 microm, and the peak concentration of its active metabolite, 8-oxo-O(6)BG, was 35 +/- 10 microm. O(6)BG was rapidly eliminated with a half-life of 85 +/- 140 min, area under the curve of 795 +/- 320 microm. min and clearance of 760 +/- 400 ml/min/m(2). The area under the curve of 8-oxo-O(6)BG when extrapolated to infinity was 22,700 +/- 11,800 microm. min. The clearance and terminal half-life of 8-oxo-O(6)BG were 30 +/- 15 ml/min/m(2) and 360 +/- 220 min, respectively. CONCLUSIONS: There is rapid elimination of O(6)BG after i.v. administration over 1 h. In contrast, the terminal half-life for the active metabolite, 8-oxo-O(6)BG, is 4-fold longer. The pharmacokinetic parameters for O(6)BG and 8-oxo-O(6)BG are similar to those reported previously in adults.     

Prevention of menstruation with leuprorelin (GnRH agonist) in women undergoing myelosuppressive chemotherapy or radiochemotherapy for hematological malignancies: a pilot study.

Vaginal bleeding during aplasia can induce transfusion support, infection and discomfort. Oral and intramuscular hormonotherapy can be toxic and/or difficult to manage (mucositis). This single-center pilot study evaluated the efficacy and safety of leuprorelin (L) in preventing heavy vaginal bleeding in 20 nonmenopausal women with leukemia, lymphoma or myeloma and foreseable therapy-induced thrombocytopenia. Until platelet recovery, patients received subcutaneous injections of L, with concomitant nomegestrol acetate (NA) during the first 35 days to prevent flare-up. Median age was 33 years (18-48). Platelet nadir was < 20 x 10(9)/l in 17 patients; 103 L injections were performed (median per patient: 4 [1-14]). No moderate or severe adverse event was related to hormonal therapy. Seventeen patients did not experience any clinically or therapeutically relevant bleeding. Eleven spottings and 8 metrorrhagias (mean duration: 3 days) occurred in 11 patients, requiring enhanced NA in 3 cases (baseline platelet count was < 20 x 10(9)/l in 1 pt, premature termination of NA [the single platelet transfusion for metrorrhagia] in 1 pt, and endometrial hyperplasia (EH) in the third). In patients without EH, only 5 spottings were observed after the third injection, without neither clinical nor therapeutic impact (63 injections). In conclusion, leuprorelin administration is safe and effective in preventing vaginal bleeding. The sustained-release form and subcutaneous administration offer quality of life advantages.     

Medical and toxicological aspects of occupational nickel exposure in the Federal Republic of Germany--clinical results (carcinogenicity, sensitization) and preventive measures (biological monitoring)

In recent years reports on nickel-related diseases in the Federal Republic of Germany have been increasingly frequent. As a result, medical scientific institutions were called upon to clarify both the occupational medical and clinical, as well as the toxicological aspects of the situation. The main clinical finding was the increased incidence of malignant neoplasias in the respiratory tracts, in particular after many years of nickel exposure in refineries. Between 1967 and 1981, seven malignant neoplasms were legally recognized as occupation-related. Additionally, in the last two years, the existence of nickel-induced malignant neoplasms has been suspected in 16 cases, and the statutory procedure for the recognition of occupational diseases instituted. Our overview presents occupational-medical and clinical aspects. Among allergic nickel-induced conditions, eczematous skin diseases predominate. In addition, case reports of asthma have been published. Statistical evaluations showed that up to 17% of all occupational allergies may be related to occupational exposure to nickel. In this situation, preventive measure are of particular importance. To estimate exposure levels, both the measurement of the agent at the workplace and the quantitative determination of nickel in biological material can be used. The measurement of nickel excretion by the kidney has proved particularly useful in occupational medicine. In addition to clinical surveillance, it is recommended that this measurement should be performed on exposed persons at regular intervals.     

Better outcomes of modified myeloablative conditioning without antithymocyte globulin versus myeloablative conditioning in cord blood transplantation for hematological malignancies: A retrospective (development) and a prospective (validation) study

Cord blood transplantation (CBT) is an effective option for treating hematological malignancies, but graft failure (GF) remains the primary cause of therapy failure. Thus, based on myeloablative conditioning (MAC) of busulfan with cyclophosphamide (Bu/Cy) or total body irradiation with Cy (TBI/Cy), fludarabine (Flu) was added to Bu/Cy and cytarabine (CA) to TBI/Cy for a modified myeloablative conditioning (MMAC). To compare the prognosis of MMAC with MAC, we conducted a retrospective study including 58 patients who underwent CBT with MAC or MMAC from 2000 to 2011. Neutrophil and platelet engraftment rate, overall survival (OS) and disease free survival (DFS) were significantly higher in the MMAC group (adjusted hazard ratio [HR], 2.58, 2.43, 0.36 and 0.37; p < 0.01, p = 0.01, p = 0.02 and p = 0.02, separately). Nonrelapse mortality (NRM) was comparable (p = 0.183). To validate the outcomes noted in the MMAC group, we conducted a prospective single‐arm clinical trial including 188 patients who underwent CBT with MMAC from 2011 to 2015. Engraftment rate, survival and NRM of the MMAC group in the prospective trail (MMAC‐P) were similar to the MMAC group in the retrospective study (MMAC‐R). This study is the first to demonstrate the superiority of MMAC to MAC in CBT for hematological malignancies.     

Hemangiopericytoma. A clinicopathologic study and long-term followup of 60 patients.

The clinical courses of 60 patients with hemangiopericytoma of the somatic soft tissues are summarized in this retrospective study. The tumors were subjected to a comparative histologic review and classified as benign (12 lesions), borderline malignant (16 lesions), and malignant (32 lesions). Tumors with 1 mitotic figure per 10 high-power field and moderate cellular anaplasia or 1 mitotic figure per 20 high-power fields and moderate cellular anaplasia may be expected to follow a malignant clinical course. Six of the 16 tumors with these microscopic features (borederline lesions) metastasized (37.5%), and 6 exhibited local recurrences after excision. Of the 32 malignant tumors, 25 (78%) metastasized. Twenty-three patients with malignant tumors were followed for more than 5 years or until death from tumor, and only one patient was alive and free of disease. Fifteen of the 23 patients experienced one of more local recurrences. None of the benign tumors metastasized. Surgical ablation of hemangiopericytioma is, in our experience, the only satisfactory method of treatment. Amputation of an extremity need be done only when the location of the lesion precludes a wide local excision. Local recurrent tumor was experienced by 22 patients after an inadequate local excision. Long-term follow-up is recommended because metastasis became apparent in 11% of patients with malignant tumors and 7% with borderline tumors after 5 "disease-free" years.     

Outbreak of severe disseminated aspergillosis in a flock of ostrich (Struthio camelus)

This study was undertaken to describe clinical, mycological and histopathological findings in black neck ostriches affected with severe aspergillosis in a flock including 80 birds, near Tehran, Iran. The signs included anorexia, depression, notable weight loss, diarrhoea, severe respiratory distress and death. Grossly, the lungs showed numerous white to yellow caseous nodules and the walls of the thoracic and abdominal air sacs were thickened with inflammatory exudates containing cellular debris, necrotic masses and green mold colonies. Multiple nodules were observed in the liver, spleen and gastrointestinal tract as well. Histopathologically, there were conidial heads and fungal hyphae in the air sacs and multifocal necrotic and granulomatous lesions with septated and dichotomously branched hyphae in various tissues, which were stained with haematoxylin and eosin and Grocott's methenamine silver nitrate. Aspergillus fumigatus was isolated in various tissues taken from affected ostriches.     

Intestinal alkalization as a possible preventive mechanism in irinotecan (CPT-11)-induced diarrhea.

The therapeutic efficacy of irinotecan (CPT-11), a DNA topoisomerase inhibitor, is often limited by the induction of severe late-onset diarrhea. This prodrug and its active metabolite, 7-ethyl-10-hydroxy-camptothecin (SN-38), have a labile alpha-hydroxy-lactone ring that undergoes pH-dependent reversible hydrolysis. At physiological pH and higher, equilibrium favors the less toxic carboxylate form, whereas at acidic pH, the more potent lactone form is favored. We have reported previously that the initial uptake rate of CPT-11 and SN-38 by intestinal cells was significantly different between the respective lactone and carboxylate form. Results from the present study in HT-29 cells further demonstrate the correlation between the CPT-11/SN-38 initial uptake rate and the induced toxicity, cell cycle alteration, apoptosis, and colony-forming efficiency. The exposure of HT-29 cells to SN-38 for a limited period of time (<2 h) was sufficient to induce these events. Because the decreased initial uptake of SN-38 carboxylate resulted in a reduced cellular toxicity, we postulated that the CPT-11-induced diarrhea was preventable by influencing the equilibrium toward the carboxylate form and, thus, reducing its intestinal uptake. In the golden Syrian hamster model, p.o. sodium bicarbonate supplementation (5 mg/ml in drinking water) led to alkalization of the intestinal contents. In addition, this alkalization resulted in the reduction of the histopathological damage to the mucosa of the small and large intestine, as well as a 20% reduction of the intestinal SN-38 lactone concentration of animals receiving CPT-11 (20-50 mg/kg x 7 days). Taken together, these results from in vitro and in vivo studies support intestinal alkalization by sodium bicarbonate supplementation as a preventive mechanism against CPT-11-induced diarrhea. In addition, this provides a strong rationale for the usage of this measure as an adjunct to CPT-11 treatment.