Phase I trial of two schedules of vincristine, oral irinotecan, and temozolomide (VOIT) for children with relapsed or refractory solid tumors: a Children's Oncology Group phase I consortium study

[Irinotecan plus temozolomide in refractory or relapsed pediatric solid tumors]

INTRODUCTION

The prognosis of refractory or relapsed pediatric solid tumors is very poor, and there is no standard treatment for this condition. The combination of irinotecan and temozolomide has proved useful in adults as a second-line treatment of different solid tumors. In pediatric patients, this combination has been effective in Ewing's sarcoma, neuroblastoma, and relapsed or refractory rhabdomyosarcoma.

PATIENTS AND METHODS

A retrospective study was conducted on 32 pediatric patients with refractory or relapsed solid tumors, who were treated with irinotecan and temozolomide in the Oncology Department at Children's Hospital Niño Jesus from September 2005 to June 2012. The clinical characteristics, treatment performed, toxicity and outcome, were analyzed.

RESULTS

Thirty-two patients received a total of 180 cycles. Of the 30 evaluable patients, 10 (33%) had a positive response (2 complete remission and 8 partial remission), and in 8 (27%) the disease remained stable. Almost all (94%) of the patients achieved a response in the first four cycles. Of the 180 cycles analyzed, only 50 (28%) had toxicity, and of these only 15 (8%) were grade iii-iv. The most common toxicity was diarrhea appearing in 18 patients. All patients received ambulatory treatment, except three of them who required hospitalization due to symptoms of their underlying disease.

CONCLUSION

The combination of irinotecan and temozolomide is well tolerated and active against pediatric refractory or relapsed solid tumors.

Relapsed hepatoblastoma

Successful treatment of recurrent hepatoblastoma (HB) relies largely on surgical resection. When tumors are responsive, chemotherapy can be used to render patients resectable. Various chemotherapeutic regimens studied in small numbers of patients on phase I/II trials have shown few responses. The best available data indicate that doxorubicin, if not given during intial treatment, and irinotecan are the most active agents in recurrent HB. Stem cell transplantation and radiation therapy have been reported in several patients with unclear successes. Advances in therapy for relapsed patients require concentrating enrollment in one or two phase I/II trials utilizing agents with promising preclinical data.

A critical review of the mechanism of action for the selective serotonin reuptake inhibitors: do these drugs possess anti-inflammatory properties and how relevant is this in the treatment of depression?

The selective serotonin reuptake inhibitors (SSRIs) are the most widely prescribed pharmacological treatment for depression. Since their introduction many have considered the primary mechanism by which the SSRIs produced therapeutic improvement in depression is their effect on monoaminergic signalling. In recent years, however, the credibility of the monoamine theory and the therapeutic efficacy of these compounds in the treatment of depression has been extensively criticized. In the current review the legitimacy of these criticisms is critically examined, in many instances the evidence base used to support these criticisms is found to be weak. Nevertheless, the apparent 'failure' of the monoamine theory has been of benefit in motivating research into alternative mechanisms through which the SSRIs may act. Given research demonstrating that depressive symptoms are intimately linked with disturbances in pro-inflammatory signalling, perhaps the most promising discovery has been the realisation that SSRIs posses significant anti-inflammatory properties. These recent findings are discussed and contextualised with respect to the neurogenic, neurotrophic and gluatamatergic effects that these drugs also possess.

Development of anaplastic Wilms tumor and subsequent relapse in a child with diaphanospondylodysostosis

Diaphanospondylodysostosis (DSD) is a rare skeletal dysplasia syndrome resulting from disordered mesenchymal differentiation. Children with DSD generally die in utero or during the first month of life from severe thoracic insufficiency syndrome. An association of DSD with nephroblastomatosis has been observed, but the natural history of such nephroblastomatosis remains poorly characterized due to the rarity of the underlying condition. We describe a patient with DSD who developed bilateral hyperplastic nephroblastomatosis that ultimately evolved into therapy-resistant anaplastic Wilms tumor (nephroblastoma).

Rhabdomyosarcoma: review of the Children's Oncology Group (COG) Soft-Tissue Sarcoma Committee experience and rationale for current COG studies

The prognosis for children and adolescents with rhabdomyosarcoma (RMS) has improved with refinements in multi-modal therapy. Since 1972, the Intergroup Rhabdomyosarcoma Study Group (now the Children's Oncology Group Soft-Tissue Sarcoma Committee) has conducted serial studies for RMS. This review describes the IRSG and COG experience with RMS, presents the current risk stratification definitions, and provides rationale for the current generation of COG RMS studies.

Phase I study of vincristine, irinotecan, and ¹³¹I-metaiodobenzylguanidine for patients with relapsed or refractory neuroblastoma: a new approaches to neuroblastoma therapy trial

PURPOSE

(131)I-metaiodobenzylguanidine (MIBG) is a targeted radiopharmaceutical with activity in patients with relapsed or refractory neuroblastoma. Irinotecan is a known radiosensitizer with activity in neuroblastoma. This phase I study aimed to determine the recommended phase 2 dose of MIBG together with fixed doses of vincristine and irinotecan.

EXPERIMENTAL DESIGN

Patients 1 to 30 years old with relapsed or refractory neuroblastoma and MIBG-avid tumors were eligible. All patients had autologous hematopoietic stem cells (PBSC) available and met standard phase I organ function requirements. Irinotecan (20 mg/m(2)/dose IV) was given on days 0 to 4 and 7 to 11, with vincristine (1.5 mg/m(2) IV) on days 0 and 7. MIBG was given on day 1 following a 3 + 3 phase I dose escalation design starting at 8 mCi/kg MIBG. PBSCs were administered at dose level 8 mCi/kg for prolonged myelosuppression and for all patients at 12 mCi/kg or more.

RESULTS

Twenty-four patients evaluable for dose escalation (median age, 6.7 years; range, 1.9-26.8 years) received 1 (n = 17), 2 (n = 5), or 3 (n = 2) cycles of therapy. Myelosuppression and diarrhea were the most common toxicities. Two of 6 patients at the 18 mCi/kg dose level had dose-limiting toxicity (DLT), including one with protocol-defined DLT with prolonged mild aspartate aminotransferase elevation. Eighteen mCi/kg was the recommended phase 2 dose. Six additional patients were treated at 18 mCi/kg, with one additional DLT. Responses (2 complete and 4 partial responses) occurred in 6 of 24 (25%) evaluable patients.

CONCLUSIONS

MIBG is tolerable and active at 18 mCi/kg with standard doses of vincristine and irinotecan.

Dose escalation of intravenous irinotecan using oral cefpodoxime: a phase I study in pediatric patients with refractory solid tumors

BACKGROUND

Administration of an oral cephalosporin allowed advancement of the dosage of oral irinotecan. This study investigates whether administration of an oral cephalosporin increases the maximum tolerated dose (MTD) of intravenous irinotecan.

PROCEDURE

Irinotecan was administered intravenously on Days 1-5 and Days 8-12 of a 21-day cycle with continuous oral cefpodoxime starting 2 days prior to irinotecan. Cohorts of 3-6 pediatric patients with refractory solid tumors were enrolled at 4 dosage levels, starting at the single-agent irinotecan MTD of 20 mg/m(2) /dose.

RESULTS

The 17 evaluable patients received 39 courses of therapy. None of the patients treated with 20 mg/m(2) /dose experienced dose-limiting toxicity (DLT). One of six patients treated at 30 mg/m(2) /dose experienced dose-limiting neutropenia. Two of three patients treated with 45 mg/m(2) /dose and two of five treated with 40 mg/m(2) /dose experienced dose-limiting diarrhea, with associated dehydration and anorexia. Two unconfirmed partial responses were observed after one course in a patient with Ewing sarcoma and one with paraganglioma. A child with refractory neuroblastoma had disease stabilization through 12 courses of therapy. Median (range) systemic exposure to SN-38 at the MTD (30 mg/m(2) /dose) was 67 ng-h/mL (36 to 111 ng-h/mL).

CONCLUSIONS

The MTD of intravenous irinotecan administered on a protracted schedule was increased by 50% from 20 to 30 mg/m(2) /dose with the addition of oral cefpodoxime. The most prominent DLT remained diarrhea. High interpatient variability in irinotecan pharmacokinetics was observed; however, SN-38 exposure at the MTD was greater than most reported exposures with the 20 mg/m(2) dosage.

Risk of recurrence and survival after relapse in patients with Ewing sarcoma

BACKGROUND

The prognosis in patients with relapsed Ewing sarcoma is unfavorable. Our investigation identifies factors predicting for the outcome following relapse.

PROCEDURE

We analyzed type of relapse, time to relapse and overall survival after relapse (OSr) in 714 patients with first recurrence. All patients had been treated within the Cooperative Ewing Sarcoma Studies (CESS) 81 or 86, or the European Intergroup CESS (EICESS 92). OSr time was calculated from diagnosis of first relapse to last follow-up or death.

RESULTS

Median follow-up time from diagnosis of primary disease was 2.2 years (mean = 4.0; range: 0.2-24.9). Relapse sites were local in 15%, combined local and systemic in 12%, and systemic in 73%. Among patients with a localized primary tumor, 20% relapsed locally, while 12% showed combined and 68% systemic relapse. When the primary disease was disseminated, 82% developed systemic, 13% combined, and 5% local relapse. Five-year OSr was 0.13 (SE = 0.01). Outcome following local relapse, with a 5-year survival rate of 0.24 (P < 0.001), was superior to outcome after systemic or combined recurrence. Five-year OSr was 0.07 (SE = 0.01) in patients who relapsed 0-2 years after the diagnosis of primary disease, as compared to a 5-year OSr of 0.29 (SE = 0.03) when relapse occurred later.

CONCLUSIONS

5-year OSr in Ewing sarcoma is poor (<0.2). Prognostically favorable factors are: late onset (>2 years) and strictly localized relapse.

An integrated in vitro and in vivo high-throughput screen identifies treatment leads for ependymoma

Using a mouse model of ependymoma-a chemoresistant brain tumor-we combined multicell high-throughput screening (HTS), kinome-wide binding assays, and in vivo efficacy studies, to identify potential treatments with predicted toxicity against neural stem cells (NSC). We identified kinases within the insulin signaling pathway and centrosome cycle as regulators of ependymoma cell proliferation, and their corresponding inhibitors as potential therapies. FDA approved drugs not currently used to treat ependymoma were also identified that posses selective toxicity against ependymoma cells relative to normal NSCs both in vitro and in vivo, e.g., 5-fluorouracil. Our comprehensive approach advances understanding of the biology and treatment of ependymoma including the discovery of several treatment leads for immediate clinical translation.

Camptothecin-based regimens for treatment of ewing sarcoma: past studies and future directions

New therapies are needed to improve survival for patients with Ewing sarcoma. Over the past decade, camptothecin agents such as topotecan and irinotecan have demonstrated activity against Ewing sarcoma, especially in combination with alkylating agents. Previous studies have shown camptothecin-based combinations to be tolerable outpatient strategies that are attractive for salvage therapy. This paper highlights important issues related to drug dosing, schedule of administration, pharmacokinetics, toxicity, and activity of commonly used camptothecin-based regimens. Also discussed are strategies for incorporating these regimens into therapy for newly diagnosed patients, including several potential possibilities for combination with targeted agents.

Phase II study of irinotecan and temozolomide in children with relapsed or refractory neuroblastoma: a Children's Oncology Group study

PURPOSE

This phase II study was conducted to determine the response rate associated with use of irinotecan and temozolomide for children with relapsed/refractory neuroblastoma.

PATIENTS AND METHODS

Patients with relapsed/refractory neuroblastoma measurable by cross-sectional imaging (stratum 1) or assessable by bone marrow aspirate/biopsy or metaiodobenzylguanidine (MIBG) scan (stratum 2) received irinotecan (10 mg/m(2)/dose 5 days a week for 2 weeks) and temozolomide (100 mg/m(2)/dose for 5 days) every 3 weeks. Response was assessed after three and six courses using International Neuroblastoma Response Criteria. Of the first 25 evaluable patients on a given stratum, five or more patients with complete or partial responses were required to conclude that further study would be merited.

RESULTS

Fifty-five eligible patients were enrolled. The objective response rate was 15%. Fourteen patients (50%) on stratum 1 and 15 patients (56%) on stratum 2 had stable disease. Objective responses were observed in three of the first 25 evaluable patients on stratum 1 and five of the first 25 evaluable patients on stratum 2. Less than 6% of patients experienced ≥ grade 3 diarrhea. Although neutropenia was observed, less than 10% of patients developed evidence of infection while neutropenic.

CONCLUSION

The combination of irinotecan and temozolomide was well tolerated. The objective response rate of 19% in stratum 2 suggests that this combination may be effective for patients with neuroblastoma detectable by MIBG or marrow analysis. Although fewer objective responses were observed in patients with disease measurable by computed tomography/magnetic resonance imaging, patients in both strata seem to have derived clinical benefit from this therapy.