A phase I study of carboplatin in children with acute leukemia in bone marrow relapse. A report from the Childrens Cancer Group

Carboplatin-Induced Hematuria With Obstructive Acute Kidney Injury

Platinum-based chemotherapeutic agents such as cisplatin, carboplatin, and oxaliplatin are used as adjuvant or neoadjuvant agents in malignancies of the ovary, cervix, lymphoma, head and neck, and breast. Cisplatin is most commonly used until the carboplatin is approved by the Food and Drug Administration (FDA). Cisplatin is not tolerated in many patients due to severe nausea and renal tubular injury. Carboplatin is used in patients where side effects limit the uses of cisplatin. Although carboplatin is least commonly associated with hematuria, we report a case of carboplatin-induced hematuria with obstructive acute kidney injury (AKI). Our patient, a 63-year-old female diagnosed with triple-negative breast carcinoma and post-mastectomy, was started on adjuvant chemotherapy, with carboplatin 700 mg and paclitaxel 250 mg. She developed hematuria with ureter obstruction due to clots, resulting in obstructive AKI. The patient continued to have oliguria and worsening symptoms, and thus, the ureter was stented. The patient's renal function returned to the baseline. In this case, we highlight the fact that carboplatin can cause hematuria with ureter obstruction. Adequate hydration before infusing carboplatin as in cisplatin can reduce the complications.

Gross hematuria secondary to use of carboplatin in neoadjuvant treatment of breast cancer with HER2 overexpression

Breast cancer is a high prevalent neoplasia in women worldwide, and platinum compounds are widely used to treat it. On rare occasions, macroscopic hematuria associated with carboplatin has been identified. Thus, the present study aims to report a rare case of a female patient diagnosed with invasive ductal carcinoma, which presented hematuria secondary to carboplatin, showing improvement of the condition after 4 days of expectant treatment with clot lavage. Due to the scant description of hematuria secondary to carboplatin in the scientific literature, it is essential to report such case in order to assist and enrich the understanding of this event.

Phase I and Phase II Objective Response Rates are Correlated in Pediatric Cancer Trials: An Argument for Better Clinical Trial Efficiency

Although many phase I trials report tumor response, formal analysis of efficacy is deferred to phase II. We reviewed paired phase I and II pediatric oncology trials to ascertain the relationship between phase I and II objective response rate (OR%). Single-agent phase I trials were paired with corresponding phase II trials (comparable study drug, dosing schedule, and population). Phase I trials without efficacy data or a matching phase II trial were excluded. OR% was tabulated for all trials, and phase II authors' subjective conclusions regarding efficacy were documented; 35 pairs of trials were analyzed. The correlation between phase I and II OR% was 0.93. Between phase II studies with a "positive" conclusion versus a "negative" one, there was a statistically significant difference in mean phase I OR% (32.0% vs. 4.5%, P<0.001). Thirteen phase II studies were undertaken despite phase I OR% of 0%; only 1 had a "positive" conclusion, and none exceeded OR% of 15%. OR% are highly correlated between phase I and II pediatric oncology trials. Although not a formal measure of drug efficacy, phase I OR% may provide an estimate of phase II response, inform phase II study design, and should be given greater consideration.

Hemorrhagic cystitis in a dog receiving carboplatin

An 8 yr old castrated male Labrador retriever mixed-breed dog with osteosarcoma (OSA) of the left proximal humerus receiving carboplatin presented 10 days after the third chemotherapy treatment with hematuria, stranguria, and pollakiuria. A presumptive diagnosis of hemorrhagic cystitis was made based on clinical signs, urinalysis, and cytologic analysis of a traumatic catheterization sample. Carboplatin was removed from the chemotherapy treatment plan and was substituted with doxorubicin. The dog was treated with meloxicam for pain, and the cystitis signs subsided over a period of 4 wk. Carboplatin is commonly used as adjuvant chemotherapy for dogs with OSA following amputation and is not known to cause hematuria in dogs, although there are reports of this occurring in humans. To the authors' knowledge, there are no reports in the veterinary literature of this toxicity.

Renal pelvic hemorrhage and acute renal failure associated with carboplatin therapy

A 44-year-old woman with ovarian cancer and normal renal function developed gross hematuria after carboplatin therapy. Laboratory investigation revealed elevated blood urea nitrogen and serum creatinine values. Computed tomography scan of the abdomen and pelvis with or without contrast revealed bilateral hydronephrosis with high-attenuation material within the left renal pelvis and both ureters consistent with blood. Delayed images at 3 hours revealed intense nephrogram with delayed excretion of contrast bilaterally. She underwent cystoscopy and placement of ureteral stent bilaterally. She had brisk diuresis with associated progressive decrease in serum creatinine to baseline value.

Pediatric Phase I Trials in Oncology: An Analysis of Study Conduct Efficiency

Purpose

To determine the efficacy and safety of pediatric phase I oncology trials in the era of dose-intensive chemotherapy and to analyze how efficiently these trials are conducted.

Methods

Phase I pediatric oncology trials published from 1990 to 2004 and their corresponding adult phase I trials were reviewed. Dose escalation schemes using fixed 30% dose increments were studied to theoretically determine whether trials could be completed utilizing fewer patients and dose levels.

Results

Sixty-nine pediatric phase I oncology trials enrolling 1,973 patients were identified. The pediatric maximum-tolerated dose (MTD) was strongly correlated with the adult MTD (r = 0.97). For three-fourths of the trials, the pediatric and adult MTD differed by no more than 30%, and for more than 85% of the trials, the pediatric MTD was less than or equal to 1.6 times the adult MTD. The median number of dose levels studied was four (range, two to 13). The overall objective response rate was 9.6%, the likelihood of experiencing a dose-limiting toxicity was 24%, and toxic death rate was 0.5%.

Conclusion

Despite the strong correlation between the adult and pediatric MTDs, more than four dose levels were studied in 40% of trials. There appeared to be little value in exploring dose levels greater than 1.6 times the adult MTD. Limiting pediatric phase I trials to a maximum of four doses levels would significantly shorten the timeline for study conduct without compromising safety.

Use of microdialysis to study platinum anticancer agent pharmacokinetics in preclinical models

Microdialysis sampling of blood and extracellular fluid (ECF) of living tissue offers unique advantages for studying anticancer drug distribution, metabolism, and mechanisms of tumor drug resistance. We applied microdialysis sampling in a rat model to describe the pharmacokinetics of cisplatin and carboplatin simultaneously in blood and several peripheral tissues, including tumor tissue. After i.v. bolus drug administration, samples were collected every 10 min for 4-6 h using microdialysis probes implanted into the jugular vein, kidney, and either liver or subcutaneously growing breast tumor tissue in anesthetized Fisher 344 rats. Analyte concentrations are expressed as absolute extracellular concentrations obtained by correction of the data for in vivo recovery. For cisplatin, peak renal concentrations (mean, 36.7 and 80.1 micrograms/mL) always exceeded peak plasma (8.4 and 13.2 micrograms/mL) and hepatic (6.3 and 10.4 micrograms/mL) concentrations following 5 and 10 mg/kg doses, respectively. For carboplatin, doses of 20 and 30 mg/kg also resulted in high peak renal concentrations, which were similar at both dose levels (mean, 87.9 and 89.3 micrograms/mL). However, at 30 mg/kg peak hepatic carboplatin concentrations were increased significantly, resulting in a disproportionate 3.5-fold increase in mean AUC at the higher dose level. Tumor cisplatin and carboplatin AUCs were similar to that in the circulation, but variable, ranging from 52 to 109% of the corresponding plasma AUCs. Microdialysis was determined to be a reliable methodology for examining the in vivo disposition of platinum anticancer agents in multiple tissue types. Our results revealed expected large renal exposures following i.v. administration, and variable tumor exposure with dose. Significant increases in hepatic carboplatin exposure with increasing dose suggest a possible mechanism for high-dose carboplatin-induced hepatic toxicity.

A phase I study of nolatrexed dihydrochloride in children with advanced cancer. A United Kingdom Children's Cancer Study Group Investigation

A phase I study of nolatrexed, administered as a continuous 5 day intravenous infusion every 28 days, has been undertaken for children with advanced malignancy. 16 patients were treated at 3 dose levels; 420, 640 and 768 mg/m(2)24 h(-1). 8 patients were evaluable for toxicity. In the 6 patients treated at 768 mg/m(2)24 h(-1), dose-limiting oral mucositis and myelosuppression were observed. Plasma nolatrexed concentrations and systemic exposure, measured in 14 patients, were dose related, with mean AUC values of 36 mg(-1)ml(-1)min(-1), 50 mg ml(-1)min(-1)and 80 mg ml(-1)min(-1)at the 3 dose levels studied. Whereas no toxicity was encountered if the nolatrexed AUC was <45 mg ml(-1)min(-1), Grade 3 or 4 toxicity was observed with AUC values of >60 mg ml(-1)min(-1). Elevated plasma deoxyuridine levels, measured as a surrogate marker of thymidylate synthase inhibition, were seen at all of the dose levels studied. One patient with a spinal primitive neuroectodermal tumour had stable disease for 11 cycles of therapy, and in two patients with acute lymphoblastic leukaemia a short-lived 50% reduction in peripheral lymphoblast counts was observed. Nolatrexed can be safely administered to children with cancer, and there is evidence of therapeutic activity as well as antiproliferative toxicity. Phase II studies of nolatrexed in children at the maximum tolerated dose of 640 mg/m(2)24 h(-1)are warranted.

Phase I trials in pediatric oncology: perceptions of pediatricians from the United Kingdom Children's Cancer Study Group and the Pediatric Oncology Group

PURPOSE

To identify areas of concern regarding the conduct of phase I trials, the perceived expectations and motivations of the parents of children entered, the expectations of toxicity and benefit, and the ethical concerns of pediatric hematologists and oncologists in the United Kingdom and North America.

METHODS

A survey instrument consisting of 19 open- and closed-ended questions was sent to United Kingdom Children's Cancer Study Group (UKCCSG)- and Pediatric Oncology Group (POG)-affiliated pediatricians.

RESULTS

Fifty-three UKCCSG- and 78 POG-affiliated pediatricians responded. Thirty-two UKCCSG and 51 POG respondents had previously entered at least one child into a phase I study. Overall, respondents believed that parents entered their children for medical benefit, altruism, and hope of cure. Although many respondents believed that children could benefit from medical improvement, feelings of altruism, and maintenance of hope, the chance of cure or complete remission was thought to be small. Similarly, parents were thought to potentially benefit through altruism and maintenance of hope. Whereas 83% of UKCCSG respondents indicated that phase I trials were associated with ethical difficulties, this was a concern for 48% of POG respondents. The main ethical concerns of respondents were risk of toxicity, consent of the child, unrealistic hope, and coercion.

CONCLUSION

The respondents in this survey expressed mainly ethical concerns regarding the conduct of phase I trials and had realistic expectations of the potential for toxicity and benefit for those children who participate in these studies.

Phase I therapy trials in children with cancer

PURPOSE

This study examined the response and toxicity rates of antineoplastic drugs evaluated in phase I clinical trials in children to identify trends in response and toxicity over time.

PATIENTS AND METHODS

Full length, peer-reviewed articles describing the results of single agent phase I therapy trials in children younger than 21 years with cancer were reviewed. Tumor-specific response data and doses of drugs that resulted in objective responses were noted. Deaths that occurred on study caused by drug toxicity, progressive disease (PD), or complications of marrow aplasia were identified, along with drug doses that resulted in toxic death. Temporal trends in response rates, toxicity, and number of patients entered in trials were examined.

RESULTS

A total of 1,606 patients with cancer were enrolled in 56 single-agent pediatric phase I therapy trials published between 1978 and 1996. Of these, 1,257 were evaluated for response by tumor type. The overall objective response rate was 7.9%. Response rates were highest for patients with neuroblastoma (17.7%) and acute myelogenous leukemia (11.6%). Patients with osteosarcoma and rhabdomyosarcoma had response rates of < 3%. Sixty percent of responses in patients with solid tumors occurred at 81 to 100% of the maximum tolerated dose (MTD), although 42% of responses in patients with leukemia occurred at > 100% of the MTD. Death on study was noted in 7.0% of all patients entered in trials. Only 0.7% of patients experienced a death related to drug toxicity. PD accounted for the death of 5.6% of study participants. A trend of increasing response rate despite smaller trial size was noted over the last 7 years of this period.

CONCLUSION

Phase I trials in children with cancer represent a safe mechanism to determine the MTD, toxicity profile, and pharmacokinetics of new agents for use in children with cancer.

Metallothionein (MT)-null mice are sensitive to cisplatin-induced hepatotoxicity

cis-Diamminedichloroplatinum (cisplatin) is an important anticancer drug used to treat solid tumors. The nephrotoxicity of cisplatin is recognized as the most important dose-limiting factor, but high doses of cisplatin also produce hepatotoxicity. However, little is known about cisplatin-induced liver injury and the role of metallothionein, a cysteine-rich, metal-binding protein, in modulating its hepatotoxicity. This study was designed to examine cisplatin hepatotoxicity in control and metallothionein-I/II knockout (MT-null) mice. Animals were given a single injection of cisplatin (50-200 mumol/kg i.p.), and liver injury was evaluated 3-16 h later. Cisplatin produced dose- and time-dependent liver injury, as evidenced by increased serum activity of alanine aminotransferase (ALT), as well as by histopathology. Apoptosis, rather than necrosis, predominates in cisplatin-induced liver injury, as indicated by increased numbers of apoptotic cells (hematoxylin and eosin staining), in situ apoptotic DNA detection, and DNA fragmentation on agarose gel electrophoresis. MT-null mice were more sensitive than controls to cisplatin-induced hepatotoxicity. Cisplatin (200 mumol/kg) was lethal to 12% of control mice, but 60% of MT-null mice died within 16 h. At the dose of 150 mumol/kg, serum ALT activities were increased 2-fold in control mice compared to 6.5-fold in MT-null mice. Apoptotic lesions were more pronounced in MT-null than in control mice. MT-null mice were also more susceptible than controls to cisplatin-induced nephrotoxicity, as evidenced by having higher blood urea nitrogen concentrations. Furthermore, cultured MT-null hepatocytes were more sensitive than control cells to the cytotoxicity of cisplatin (50-200 microM), as indicated by lactate dehydrogenase leakage into the medium. These results demonstrate that (1) high doses of cisplatin produce hepatotoxicity, with apoptosis as the major lesion, and (2) MT protects against cisplatin-induced liver injury.

Interferon-alpha enhances the cytotoxic and cytostatic activities of chemotherapeutic drugs in human myeloid leukemia cells

In comparison with chemotherapeutic drugs, IFN-alpha showed a significantly better median survival rate in CML patients; therefore, current studies focus on the identification of the proper chemotherapeutic drug, with the most effective synergistic interaction with IFN-alpha for the elimination of the human myeloid leukemia cell clone. The cytostatic and cytotoxic effects of combining IFN-alpha with each of the three chemotherapeutic drugs carboplatin, daunorubicin, and cytarabine were evaluated in three human myeloid leukemia cell lines representing different stages of differentiation: MHH225 (CD34-positive multilineage), HL-60 (promyelocytic), and U937 (monoblastic) in both liquid suspension and agar clonogenic cultures. The ED90 (the concentrations of chemotherapeutic drugs required for 90% inhibition of colony formation or cell death) in human myeloid leukemia cells were in the following order: daunorubicin > carboplatin > cytarabine, with HL-60 the most sensitive and MHH225 the least sensitive. Whereas IFN-alpha failed to decrease significantly the ED90 of cytarabine in the three human myeloid leukemia cell lines, it significantly decreased the ED90 of carboplatin and to a lesser extent daunorubicin in both liquid suspension and agar clonogenic cultures. The present results are in line with the previous results of a negative interaction between IFN-alpha and cytarabine both in vitro in K562 human leukemia and in vivo in L1210 murine leukemia, and a synergistic cytostatic interaction between IFN-alpha and carboplatin in K562 cells. The significant synergism between IFN-alpha and carboplatin was observed in all four human myeloid leukemia cell lines with various stages of differentiation and confirmed in both serum-free and serum-supplemented cultures applying different in vitro assays: liquid suspension, agar clonogenic, and capillary agar microclonogenic cultures. Thus, given the in vitro profound synergism between IFN-alpha and carboplatin in all four human myeloid leukemia cells tested, together with the in vivo significant antileukemic activity of both IFN-alpha and carboplatin in several reported clinical studies for myeloid leukemia patients, the clinical use of the combination of IFN-alpha and carboplatin in the treatment of CML patients could prolong the complete hematologic and cytogenetic responses and consequently improve the survival rate. On the other hand, given the negative interaction between IFN-alpha and cytarabine observed in myeloid leukemia cells, together with the inferior cytogenetic responses observed in CML patients treated with the combination of IFN-alpha and cytarabine, caution should be exercised against the continuous clinical use of the combination of IFN-alpha and cytarabine in treating CML patients. In conclusion, the present results suggest the use of carboplatin and to a lesser extent daunorubicin instead of cytarabine in combination with IFN-alpha for the treatment of CML patients.

Phase I trials in paediatric oncology--the European perspective. The New Agents Group of the United Kingdom Childrens Cancer Study Group

The current recommendations for Phase I trials should allow more confident interpretation of the toxicity and efficacy of new agents by providing a framework for multicentre and international co-operation. An overview of the aims and designs of Phase I trials is presented, along with a summary of current and recently published United Kingdom Childrens Cancer Study Group Phase I trials, and a discussion of some of the difficulties faced in the methodology and evaluation of Phase I studies in children.

Carboplatin hypersensitivity in children. A report of five patients with brain tumors

BACKGROUND

Carboplatin, which is used in the treatment of several childhood tumors, increasingly has been reported to cause hypersensitivity reactions, the majority reported in adults. Five cases of children with primary brain tumors who were treated with carboplatin and developed acute allergic reactions are presented.

METHODS

The clinical history of each patient is described, as is the schedule, cumulative dose, and number of infusions of carboplatin, type of reaction, and retreatment.

RESULTS

Four of the five patients had histologically proven low grade astrocytic tumors; three had juvenile pilocytic astrocytomas, and one had a mixed oligoastrocytoma. One patient with neurofibromatosis type I had radiographically-defined bilateral optic nerve gliomas. Three patients had prior chemotherapy, one with cisplatin. All five patients developed hypersensitivity reactions such as urticaria, facial erythema, and facial swelling after multiple infusions of carboplatin. Two were retreated with carboplatin after receiving antihistamines, but still developed a reaction. Carboplatin therapy was discontinued in all patients.

CONCLUSION

The purpose of this report is to heighten awareness of this potentially serious complication of carboplatin in children so that potentially dangerous retreatment is avoided. As use of a weekly schedule of carboplatin in children with low grade gliomas increases, with planned therapy extending for more than 50 weeks, more hypersensitivity reactions are anticipated.