Lisocabtagene maraleucel as second-line therapy in adults with relapsed or refractory large B-cell lymphoma who were not intended for haematopoietic stem cell transplantation (PILOT): an open-label, phase 2 study.

BACKGROUND: Patients with relapsed or refractory large B-cell lymphoma after first-line treatment who are not intended for haematopoietic stem-cell transplantation (HSCT) have poor outcomes and limited treatment options. We assessed the antitumour activity and safety of lisocabtagene maraleucel, an autologous, CD19-directed chimeric antigen receptor (CAR) T-cell product, as second-line treatment in adults with relapsed or refractory large B-cell lymphoma not intended for HSCT. METHODS: PILOT, an open-label, phase 2 trial done at 18 clinical sites in the USA, included adults aged 18 years or older who had relapsed or refractory large B-cell lymphoma and PET-positive disease, had received first-line therapy containing an anthracycline and a CD20-targeted agent, were not intended for HSCT by their physician, and met at least one prespecified transplantation not intended criterion. Patients received lymphodepleting chemotherapy (intravenous fludarabine 30 mg/m2 and intravenous cyclophosphamide 300 mg/m2 daily for 3 days) followed 2-7 days later by two sequential lisocabtagene maraleucel infusions (equal target doses of CD8+ and CD4+ CAR+ T cells for a total target dose of 100 × 106 CAR+ T cells). The primary endpoint was the overall response rate and was assessed in all patients who received lisocabtagene maraleucel and had confirmed PET-positive disease before lisocabtagene maraleucel administration based on an independent review committee according to the Lugano 2014 criteria. Safety was assessed in all patients who received lisocabtagene maraleucel. Patient follow-up is ongoing. This study is registered with ClinicalTrials.gov, NCT03483103. FINDINGS: Between July 26, 2018, and Sept 24, 2021 (data cutoff for the primary analysis), 74 patients underwent leukapheresis and 61 received lisocabtagene maraleucel (efficacy and safety sets); median age was 74 years (IQR 70-78), 24 (39%) patients were women versus 37 (61%) men, and 54 (89%) patients were White. 16 (26%) of 61 patients had an Eastern Cooperative Oncology Group performance status of 2, 33 (54%) had refractory disease, 13 (21%) relapsed within 1 year of first-line therapy, and 15 (25%) relapsed after 12 months of first-line therapy. Median on-study follow-up was 12·3 months (IQR 6·1-18·0). 49 (80% [95% CI 68-89]; p<0·0001) patients had an overall response. The most common grade 3 or worse treatment-emergent adverse events were neutropenia (29 [48%] patients), leukopenia (13 [21%]), and thrombocytopenia (12 [20%]). Lisocabtagene maraleucel-related serious treatment-emergent adverse events were reported in 13 (21%) patients. There were no treatment-related deaths. Cytokine release syndrome occurred in 23 (38%; grade 3 in one) patients and neurological events in 19 (31%; grade 3 in three) patients, with no grade 4 events or deaths. INTERPRETATION: These results support lisocabtagene maraleucel as a potential second-line treatment in patients with large B-cell lymphoma for whom HSCT is not intended. FUNDING: Juno Therapeutics, a Bristol-Myers Squibb company.

Evaluation of the CLL-IPI in relapsed and refractory chronic lymphocytic leukemia in idelalisib phase-3 trials.

The CLL-IPI is a risk-weighted prognostic model for previously untreated patients with chronic lymphocytic leukemia (CLL), but has not been evaluated in patients with relapsed CLL or on novel therapies. We evaluated the CLL-IPI in 897 patients with relapsed/refractory CLL in 3 randomized trials testing idelalisib (PI3Kδ inhibitor). The CLL-IPI identified patients as low (2.2%), intermediate (12.8%), high (48.7%), and very high (36.2%) risk and was prognostic for survival (log-rank p < .0001; C-statistic 0.706). Of CLL-IPI factors, age >65, ß2-microglobulin >3.5mg/L, unmutated immunoglobulin heavy chain variable region gene, and deletion 17p/TP53 mutation were independently prognostic, but Rai I-IV or Binet B/C was not. The CLL-IPI is prognostic for survival in relapsed CLL and with idelalisib therapy. However, low/intermediate risk is uncommon, and regression parameters of individual factors in this risk-weighted model appear different in relapsed CLL. Reassessment of the weighting of the individual variables might optimize the model in this setting.

Pathological assessment of gastrointestinal biopsies from patients with idelalisib-associated diarrhea and colitis.

AIM: Idelalisib (IDELA) treatment is associated with diarrhea/colitis (incidence of ∼15% grade ≥3). We performed a retrospective analysis of gastrointestinal biopsies from 29 patients treated with IDELA across nine clinical trials. METHODS: A central core laboratory performed histopathologic review, immunohistochemistry, and droplet digital PCR viral studies. These results were correlated with tissue immune profiling data and morphologic features per modified Geboes score. RESULTS: Out of 29 eligible patients with abdominal pain or diarrhea, 24 (82.8%) had reported adverse event terms of diarrhea and/or colitis. Infectious pathogens were detected in 9/29 samples. Most biopsies presented with mixed/inflammatory infiltrates and contained increased numbers of FOXP3+ cells versus normal controls. CONCLUSION: This study revealed evidence of T-cell dysregulation and a substantial infectious component in association with IDELA-related diarrhea/colitis.

SIMPLIFY-1: A Phase III Randomized Trial of Momelotinib Versus Ruxolitinib in Janus Kinase Inhibitor-Naïve Patients With Myelofibrosis.

Purpose We evaluated the efficacy and safety of momelotinib, a potent and selective Janus kinase 1 and 2 inhibitor (JAKi), compared with ruxolitinib, in JAKi-naïve patients with myelofibrosis. Patients and Methods Patients (N = 432) with high risk or intermediate-2 risk or symptomatic intermediate-1 risk myelofibrosis were randomly assigned to receive 24 weeks of treatment with momelotinib 200 mg once daily or ruxolitinib 20 mg twice a day (or per label), after which all patients could receive open-label momelotinib. The primary end point was a ≥ 35% reduction in spleen volume at 24 weeks of therapy. Secondary end points were rates of symptom response and effects on RBC transfusion requirements. Results A ≥ 35% reduction in spleen volume at week 24 was achieved by a similar proportion of patients in both treatment arms: 26.5% of the momelotinib group and 29% of the ruxolitinib group (noninferior; P = .011). A ≥ 50% reduction in the total symptom score was observed in 28.4% and 42.2% of patients who received momelotinib and ruxolitinib, respectively, indicating that noninferiority was not met ( P = .98). Transfusion rate, transfusion independence, and transfusion dependence were improved with momelotinib (all with nominal P ≤ .019). The most common grade ≥ 3 hematologic abnormalities in either group were thrombocytopenia and anemia. Grade ≥ 3 infections occurred in 7% of patients who received momelotinib and 3% of patients who received ruxolitinib. Treatment-emergent peripheral neuropathy occurred in 10% of patients who received momelotinib (all grade ≤ 2) and 5% of patients who received ruxolitinib (all grade ≤ 3). Conclusion In JAKi-naïve patients with myelofibrosis, 24 weeks of momelotinib treatment was noninferior to ruxolitinib for spleen response but not for symptom response. Momelotinib treatment was associated with a reduced transfusion requirement.

Efficacy and safety of idelalisib in combination with ofatumumab for previously treated chronic lymphocytic leukaemia: an open-label, randomised phase 3 trial.

BACKGROUND: Idelalisib, a selective inhibitor of PI3Kδ, is approved for the treatment of patients with relapsed chronic lymphocytic leukaemia (CLL) in combination with rituximab. We aimed to assess the efficacy and safety of idelalisib in combination with a second-generation anti-CD20 antibody, ofatumumab, in a similar patient population. METHODS: In this global, open-label, randomised, controlled phase 3 trial, we enrolled patients with relapsed CLL progressing less than 24 months from last therapy. Patients refractory to ofatumumab were excluded. Patients were stratified by relapsed versus refractory disease, presence or absence of del(17p) or TP53 mutation, or both, and IGHV mutated versus unmutated. We randomised patients in a 2:1 ratio using a web-based interactive system that generated a unique treatment code, and assigned patients to receive either idelalisib plus ofatumumab (oral idelalisib 150 mg twice daily continuously plus ofatumumab 300 mg intravenously in week 1, then 1000 mg intravenously weekly for 7 weeks, and every 4 weeks for 16 weeks) or ofatumumab alone (ofatumumab dosing as per the combination group, except 2000 mg was substituted for the 1000 mg dose). An independent review committee assessed response, including progressive disease, based on imaging using modified International Workshop on Chronic Lymphocytic Leukaemia 2008 criteria. The primary endpoint was progression-free survival assessed by an independent review committee in the intention-to-treat population. We did a primary analysis (data cutoff Jan 15, 2015) and an updated analysis (data cutoff Sept 1, 2015). This trial is registered with Clinicaltrials.gov, number NCT01659021. FINDINGS: Between Dec 17, 2012, and March 31, 2014, we enrolled 261 patients (median age 68 years [IQR 61-74], median previous therapies three [IQR 2-4]). At the primary analysis, median progression-free survival was 16·3 months (95% CI 13·6-17·8) in the idelalisib plus ofatumumab group and 8·0 months (5·7-8·2) in the ofatumumab group (adjusted hazard ratio [HR] 0·27, 95% CI 0·19-0·39, p<0·0001). The most frequent grade 3 or worse adverse events in the idelalisib plus ofatumumab group were neutropenia (59 [34%] patients vs 14 [16%] in the ofatumumab group), diarrhoea (34 [20%] vs one [1%]), and pneumonia (25 [14%] vs seven [8%]). The most frequent grade 3 or worse adverse events in the ofatumumab group were neutropenia (14 [16%]), pneumonia (seven [8%]), and thrombocytopenia (six [7%] vs 19 [11%] in the idelalisib plus ofatumumab group). Serious infections were more common in the idelalisib plus ofatumumab group and included pneumonia (23 [13%] patients in the idelalisib plus ofatumumab group vs nine [10%] in the ofatumumab group), sepsis (11 [6%] vs one [1%]), and Pneumocystis jirovecii pneumonia (eight [5%] vs one [1%]). 22 treatment-related deaths occurred in the idelalisib plus ofatumumab group (the most common being sepsis, septic shock, viral sepsis, and pneumonia). Six treatment-related deaths occurred in the ofatumumab group (the most common being progressive multifocal leukoencephalopathy and pneumonia). INTERPRETATION: The idelalisib plus ofatumumab combination resulted in better progression-free survival compared with ofatumumab alone in patients with relapsed CLL, including in those with high-risk disease, and thus might represent a new treatment alternative for this patient population. FUNDING: Gilead Sciences, Inc.

A phase 2 study of idelalisib plus rituximab in treatment-naïve older patients with chronic lymphocytic leukemia.

Idelalisib is a first-in-class oral inhibitor of PI3Kδ that has shown substantial activity in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). To evaluate idelalisib as initial therapy, 64 treatment-naïve older patients with CLL or small lymphocytic leukemia (median age, 71 years; range, 65-90) were treated with rituximab 375 mg/m(2) weekly ×8 and idelalisib 150 mg twice daily continuously for 48 weeks. Patients completing 48 weeks without progression could continue to receive idelalisib on an extension study. The median time on treatment was 22.4 months (range, 0.8-45.8+). The overall response rate (ORR) was 97%, including 19% complete responses. The ORR was 100% in patients with del(17p)/TP53 mutations and 97% in those with unmutated IGHV. Progression-free survival was 83% at 36 months. The most frequent (>30%) adverse events (any grade) were diarrhea (including colitis) (64%), rash (58%), pyrexia (42%), nausea (38%), chills (36%), cough (33%), and fatigue (31%). Elevated alanine transaminase/aspartate transaminase was seen in 67% of patients (23% grade ≥3). The combination of idelalisib and rituximab was highly active, resulting in durable disease control in treatment-naïve older patients with CLL. These results support the further development of idelalisib as initial treatment of CLL. This study is registered at ClinicalTrials.gov as #NCT01203930.

Multicenter phase I trial of the mitogen-activated protein kinase 1/2 inhibitor BAY 86-9766 in patients with advanced cancer.

PURPOSE: To evaluate the safety, pharmacokinetics, and pharmacodynamics of BAY 86-9766, a selective, potent, orally available, small-molecule allosteric inhibitor of mitogen-activated protein kinase 1/2 in patients with advanced solid tumors. EXPERIMENTAL DESIGN: BAY 86-9766 was administered orally daily in 28-day courses, with doses escalated to establish the maximum-tolerated dose (MTD). An expanded cohort was evaluated at the MTD. Pharmacokinetic and pharmacodynamic parameters were assessed, with extracellular signal-regulated kinase (ERK) phosphorylation evaluated in paired biopsies from a subset of the expanded MTD cohort. Tumor specimens were evaluated for mutations in select genes. RESULTS: Sixty-nine patients were enrolled, including 20 patients at the MTD. The MTD was 100 mg given once-daily or in two divided doses. BAY 86-9766 was well-tolerated. The most common treatment-related toxicities were acneiform rash and gastrointestinal toxicity. BAY 86-9766 was well-absorbed after oral administration (plasma half-life ~12 hours), and displayed dose proportional pharmacokinetics throughout the tested dose range. Continuous daily dosing resulted in moderate accumulation at most dose levels. BAY 86-9766 suppressed ERK phosphorylation in biopsied tissue and tetradecanoylphorbol acetate-stimulated peripheral blood leukocytes. Of 53 evaluable patients, one patient with colorectal cancer achieved a partial response and 11 patients had stable disease for 4 or more courses. An ocular melanoma specimen harbored a GNAQ-activating mutation and exhibited reduced ERK phosphorylation in response to therapy. CONCLUSION: This phase I study showed that BAY 86-9766 was well-tolerated, with good oral absorption, dose proportional pharmacokinetics, target inhibition at the MTD, and some evidence of clinical benefit across a range of tumor types.

A pediatric phase I trial and pharmacokinetic study of ispinesib: a Children's Oncology Group phase I consortium study.

PURPOSE: To determine the maximum-tolerated dose, dose-limiting toxicities, and pharmacokinetics of the kinesin spindle protein inhibitor ispinesib in pediatric patients with recurrent or refractory solid tumors. SUBJECTS AND METHODS: Ispinesib was administered as 1-hr intravenous infusion weekly × 3, every 28 days. Cohorts of 3-6 patients were enrolled at 5, 7, 9, and 12 mg/m(2) /dose. Serial plasma samples for pharmacokinetic analyses were obtained after the first dose. RESULTS: Twenty-four (13 females) patients with a median (range) age of 10 years (1-19) were enrolled in the study. At the 12 mg/m(2) dose level dose-limiting neutropenia occurred in 2/6 patients and hyperbilirubinemia in 1/6 patients, while at the 9 mg/m(2) dose level 1/6 patients had dose-limiting neutropenia. There were no objective responses, but three patients (diagnoses of anaplastic astrocytoma, alveolar soft part sarcoma, and ependymoblastoma) had stable disease for 4-7 courses. There was substantial interpatient variation in drug disposition. The median (range) terminal elimination half-life was 16 (8-44) hr and the plasma drug clearance was 5 (1-14) L/hr/m(2) . CONCLUSIONS: The maximum tolerated and recommended phase II dose for ispinesib administered weekly × 3 every 28 days for children with solid tumors is 9 mg/m(2) /dose. Plans for a phase II trial in select pediatric solid tumors are in development.

Sequential oral hydroxyurea and intravenous cytosine arabinoside in refractory childhood acute leukemia: a pediatric oncology group phase 1 study.

At concentrations >0.1 mM, hydroxyurea (HU) enhances the accumulation of cytosine arabinoside (ara-C) in leukemia cells in vitro. This study of children with refractory acute leukemia was designed to take advantage of this biochemical modulation. A fixed dose of HU and an escalating dose of ara-C were used. Oral HU (1200 mg/m2) was followed 2 hours later by ara-C (250-3100 mg/m2) intravenously in 15 minutes. The combination was given on days 1, 2, 3 and 8, 9, 10. Thirty-three children [26 acute lymphocytic leukemia (ALL), 7 acute nonlymphocytic leukemia] were treated; 29 received at least 1 full course. All patients developed grade 4 cytopenias. Other grade 3 to 4 toxicities included hyperbilirubinemia (2), elevated transaminases (3), transient gait disturbance (1), stomatitis (3), typhlitis (1), nausea/vomiting (9), and marrow aplasia >4 weeks (1). Three patients had intracranial bleeds while thrombocytopenic. Only liver toxicities and nausea/vomiting exhibited any dosage effect. The maximum tolerated dose of ara-C was 2400 mg/m2. There were 6 complete responses (5 ALL), 5 partial responses (3 ALL), and 19 patients with no response or progressive disease. There was no dosage effect for response with 2 complete responses occurring at the lowest ara-C level. Responses were transient (1 to 3 mo). Twenty of twenty-six patients achieved a peak serum HU level >0.5 mM by 2 hours after the HU dose. The mean level at 2 hours was 0.57 mM (range: 0.21 to 0.99 mM). This combination of HU and ara-C is tolerable and has efficacy in refractory leukemias. Responses at the lowest ara-C dose level suggests synergism.

Intensive chemotherapy followed by consolidative myeloablative chemotherapy with autologous hematopoietic cell rescue (AuHCR) in young children with newly diagnosed supratentorial primitive neuroectodermal tumors (sPNETs): report of the Head Start I and II experience.

BACKGROUND: Children with newly diagnosed supratentorial primitive neuroectodermal tumors (sPNET) have poor outcomes compared to medulloblastoma patients, despite similar treatments. In an effort to improve overall survival (OS) and event-free survival (EFS) and to decrease radiation exposure, the Head Start (HS) protocols treated children with newly diagnosed sPNET utilizing intensified induction chemotherapy (ICHT) followed by consolidation with myeloablative chemotherapy and autologous hematopoietic cell rescue (AuHCR). PROCEDURES: Between 1991 and 2002, 43 children with sPNET were prospectively treated on two serial studies (HS I and II). After maximal safe surgical resection, patients on HS I and patients with localized disease on HS II were treated with five cycles of ICHT (vincristine, cisplatin, cyclophosphamide, and etoposide). Patients on HS II with disseminated disease received high-dose methotrexate during ICHT. If the disease remained stable or in response, patients received a single cycle of high-dose myeloablative chemotherapy followed by AuHCR. RESULTS: Five-year EFS and OS were 39% (95%CI: 24%, 53%) and 49 (95%CI: 33%, 62%), respectively. Non-pineal sPNET patients faired significantly better than those patients with pineal sPNETs. Metastasis at diagnosis, age, and extent of resection were not significant prognostic factors. Sixty percent of survivors (12 of 20) are alive without exposure to radiation therapy. CONCLUSIONS: ICHT followed by AuHCR in young patients with newly diagnosed sPNET appears to not only provide an improved EFS and OS for patients who typically have a poor prognosis, but also it successfully permitted deferral and elimination of radiation therapy in a significant proportion of patients.

Role of carbonate in the cytotoxicity of carboplatin.

Carboplatin, [Pt(NH3)2(CBDCA-O,O')], 1, where CBDCA is cyclobutane-1,1-dicarboxylate, is used against ovarian, lung, and other types of cancer. We recently showed (Di Pasqua et al. (2006) Chem. Res. Toxicol. 19, 139-149) that carboplatin reacts with carbonate under conditions that simulate therapy to produce carbonato carboplatin, cis-[Pt(NH3)2(O-CBDCA)(CO3)]2-, 2. We use 13C and 1H NMR and UV-visible absorption spectroscopy to show that solutions containing carboplatin that have been aged in carbonate buffer under various conditions contain 1, 2, and other compounds. We then show that aging carboplatin in carbonate produces compounds that are more toxic to human neuroblastoma (SK-N-SH), proximal renal tubule (HK-2) and Namalwa-luc Burkitt's lymphoma (BL) cells than carboplatin alone. Moreover, increasing the aging time increases the cytotoxicity of the platinum solutions as measured by the increase in cell death. Although HK-2 cells experience a large loss in survival upon exposure to carbonato forms of the drug, they have the highest values of IC50 of the three cell lines studied, so that HK-2 cells remain the most resistant to the toxic effects of the carbonato forms in the culture medium. This is consistent with the well-known low renal toxicity observed for carboplatin in therapy. The uptake rates for normal Jurkat cells (NJ) and cisplatin-resistant Jurkat cells (RJ), measured by inductively coupled plasma mass spectrometry (ICP-MS), are 16.6 +/- 4.2 and 12.3 +/- 4.8 amol of Pt h-1 cell-1, respectively, when exposed to carboplatin alone. However, when these cells are exposed to carboplatin that has been aged in carbonate media, normal Jurkat cells strongly bind/take up Pt at a rate of 14.5 +/- 4.1 amol of Pt h-1 cell-1, while resistant cells strongly bind/take up 5.1 +/- 3.3 amol of Pt h-1 cell-1. Collectively, these studies show that carboplatin carbonato species may play a major role in the cytotoxicity and uptake of carboplatin by cells.

Outcome for young children newly diagnosed with ependymoma, treated with intensive induction chemotherapy followed by myeloablative chemotherapy and autologous stem cell rescue.

BACKGROUND: The purpose of this study is to investigate the efficacy of an intensive chemotherapy induction regimen followed by myeloablative chemotherapy and autologous hematopoietic stem cell rescue (AHSCR) in children with newly diagnosed ependymoma. PATIENTS AND METHODS: Twenty-nine children less than 10 years of age at diagnosis of ependymoma were enrolled on the "Head Start" studies. Twenty-four patients with localized disease received an induction regimen including five cycles of chemotherapy (cisplatin, vincristine, etoposide cyclophosphamide, and high dose methotrexate for patients with metastatic disease). Following induction, individuals without evidence of disease proceeded to marrow-ablative chemotherapy (thiotepa, carboplatin, and etoposide) with AHSCR. RESULTS: The estimated 5-year event free survival (EFS) and overall survival (OS) from diagnosis were 12% (+/-6%) and 38% (+/-10%), respectively. The toxic mortality amongst this group of 29 patients was 10.3%. Younger age (less than 18 months at diagnosis) was the only statistically significant prognostic factor. The estimated 5-year OS rate for the five patients with metastatic disease at presentation was 80% (+/-18%). Overall, radiation-free survival at 5 years from diagnosis was 8% (+/-5%). CONCLUSIONS: The use of an intensive induction chemotherapy regimen including myeloablative chemotherapy followed by AHSCR in newly diagnosed young children with ependymoma is not superior to other previously reported chemotherapeutic strategies.

Teaching teachers about childhood cancer: the effects of a web-based training program.

The purpose of this study was to examine the utility and acceptability of a modular computer-based training program on childhood cancer (eg, acute and late effects of treatment, intervention strategies) for teachers. A within-subjects design was implemented with 41 teachers and teachers in training. Participants completed tests of childhood cancer knowledge and application skills both before and after completing the web-based training. An acceptability questionnaire was completed after the training. Results indicated significant gains in knowledge and in case application, as well as high levels of acceptability of the training. It seems that a web-based training program can be accessed by teachers and in 2 to 4 hours can significantly increase cancer knowledge in an acceptable manner.

Modification and uptake of a cisplatin carbonato complex by Jurkat cells.

The interactions of Jurkat cells with cisplatin, cis-[Pt(15NH3)2Cl2]1, are studied using 1H-15N heteronuclear single quantum coherence (HSQC) NMR and inductively coupled plasma mass spectrometry. We show that Jurkat cells in culture rapidly modify the monocarbonato complex cis-[Pt(15NH3)2(CO3)Cl]- (4), a cisplatin species that forms in culture media and probably also in blood. Analysis of the HSQC NMR peak intensity for 4 in the presence of different numbers of Jurkat cells reveals that each cell is capable of modifying 0.0028 pmol of 4 within approximately 0.6 h. The amounts of platinum taken up by the cell, weakly bound to the cell surface, remaining in the culture medium, and bound to genomic DNA were measured as functions of time of exposure to different concentrations of drug. The results show that most of the 4 that has been modified by the cells remains in the culture medium as a substance of molecular mass <3 kDa, which is HSQC NMR silent, and is not taken up by the cell. These results are consistent with a hitherto undocumented extracellular detoxification mechanism in which the cells rapidly modify 4, which is present in the culture medium, so it cannot bind to the cell. Because there is only a slow decrease in the amount of unmodified 4 remaining in the culture medium after 1 h, -1.1 +/- 0.4 microM h(-1), the cells subsequently lose their ability to modify 4. These observations have important implications for the mechanism of action of cisplatin.

Pediatric cerebellar pleomorphic xanthoastrocytoma with anaplastic features: a case of long-term survival after multimodality therapy.

CASE REPORT: A 4-year-old girl had a large midline cerebellar solid and cystic mass partially attached to the meninges. The original diagnosis was glioblastoma multiforme and she was treated by a gross-total surgical resection followed by chemotherapy and radiation therapy to the posterior fossa during the ensuing 14 months. She has received no further therapy and appears to be doing well 12 years later. This unusual favorable clinical outcome prompted our review of this case. METHODS: Additional special stains and immunocytochemistry were performed on the paraffin embedded tumor sections. RESULTS: We have confirmed the original histopathological observations of hypercellularity and focal nuclear pleomorphism, atypical mitoses, vascular hyperplasia, as well as focal necrosis. However, the additional stains revealed that the tumor is a relatively well-circumscribed meningeal-based astrocytic tumor (positive for GFAP) with extensive reticulin deposit and focal neuronal differentiation (positive for synaptophysin). A Ki67 labeling index is generally very low, but is positive in up to 5-10% of tumor cells focally. In the light of the favorable clinical outcome and the overall histological features, this tumor may be best reclassified as a rare example of cerebellar pleomorphic xanthoastrocytoma with foci of anaplasia.

Activation of carboplatin by carbonate.

Carboplatin, [Pt(NH3)2(CBDCA-O,O')], 1, where CBDCA is cyclobutane-1,1-dicarboxylate, is in wide clinical use for the treatment of ovarian, lung, and other types of cancer. Because carboplatin is relatively unreactive toward nucleophiles, an important question concerning the drug is the mechanism by which it is activated in vivo. Using [1H,15N] heteronuclear single quantum coherance spectroscopy (HSQC) NMR and 15N-labeled carboplatin, we show that carboplatin reacts with carbonate ion in carbonate buffer to produce ring-opened products, the nature of which depends on the pH of the medium. The assignment of HSQC NMR resonances was facilitated by studying the reaction of carboplatin in strong acid, which also produces a ring-opened product. The HSQC NMR spectra and UV-visible difference spectra show that reaction of carboplatin with carbonate at pH > 8.6 produces mainly cis-[Pt(NH3)2(CO3(-2))(CBDCA-O)]-2, 5, which contains the mono-dentate CBDCA ligand and mono-dentate carbonate. At pH 6.7, the primary product is the corresponding bicarbonato complex, which may be in equilibrium with its decarboxylated hydroxo analogue. The UV-visible absorption data indicate that the pKb for the protonation of 5 is approximately 8.6. Thus, the reaction of carboplatin with carbonate produces a mixture of ring-opened species that are anions at physiological pH. HSQC NMR studies on 15N-labeled carboplatin in RPMI culture media containing 10% fetal bovine serum with and without added carbonate suggest that carbonate is the attacking nucleophile in culture media. However, because the rate of reaction of carbonate with carboplatin at physiological pH is small, NMR peaks for ring-opened carboplatin were not detected with HSQC NMR. The rate of disappearance of carboplatin in culture medium containing 9 x 10(8) Jurkat cells is essentially the same as that in carbonate buffer, indicating that the ring-opening reaction is not affected by the presence of cells. This work shows that carbonate at concentrations found in culture media, blood, and the cytosol readily displaces one arm of the CBDCA ligand of carboplatin to give a ring-opened product, which at physiological pH is a mixture of anions. These ring-opened species may be important in the uptake, antitumor properties, and toxicity of carboplatin.

Intensive therapy with growth factor support for patients with Ewing tumor metastatic at diagnosis: Pediatric Oncology Group/Children's Cancer Group Phase II Study 9457--a report from the Children's Oncology Group.

PURPOSE: Prognosis is poor for Ewing sarcoma patients with metastasis at diagnosis. We intensified a five-drug therapy (ifosfamide, etoposide alternated with vincristine, doxorubicin, and cyclophosphamide) using filgrastim but not stem-cell support. We studied topotecan alone and combined with cyclophosphamide in therapeutic windows before the five-drug therapy. A randomly assigned proportion of patients received amifostine as a cytoprotective agent. PATIENTS AND METHODS: Eligible patients were < or = 30 years old and had histologically proven Ewing sarcoma or primitive neuroectodermal tumor (PNET) and metastasis at diagnosis. Chemotherapeutic cycles began every 21 days, after recovery from toxicities. RESULTS: One hundred ten of the 117 patients enrolled were eligible. Thirty-six patients received initial topotecan. Three had partial responses (PRs), and 17 had progressive disease (PD). Thirty-seven patients were administered topotecan and cyclophosphamide; 21 of these patients achieved PR, and one patient had PD. In a randomly assigned group of 69 patients, amifostine did not provide myeloprotection, which was measured by absolute neutrophil count, platelet count, or cycle intervals. The best responses to the overall therapy included 45 complete responses, 41 PRs, stable disease in 14 patients, and PD in five patients. For all patients, the 2-year event-free survival (EFS) rate was 24% (+/- 4%), and the overall survival rate was 46% (+/- 5%). For the 39 patients with isolated pulmonary metastases, the 2-year EFS rate was 31% (+/- 7%) compared with 20% (+/- 5%) for patients with more widespread disease. CONCLUSION: Topotecan had limited activity in patients with Ewing sarcoma or PNET metastatic at diagnosis. The topotecan-cyclophosphamide combination was active. Amifostine was not myeloprotective. Overall results showed no improvement compared with previous studies.

Phase I clinical and pharmacologic study of weekly cisplatin and irinotecan combined with amifostine for refractory solid tumors.

PURPOSE: This Phase I study was designed primarily to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of irinotecan and cisplatin with and without amifostine in children with refractory solid tumors. PATIENTS AND METHODS: Cisplatin, at a fixed dose of 30 mg/m(2), and escalating doses of irinotecan (starting dose, 40 mg/m(2)) were administered weekly for four consecutive weeks, every 6 weeks. After the MTD of irinotecan plus cisplatin was determined, additional cohorts of patients were enrolled with amifostine (825 mg/m(2)) support. Leukocyte DNA-platinum adducts and pharmacokinetics of cisplatin and WR-1065 (amifostine-active metabolite) were also determined. RESULTS: Twenty-four patients received 43 courses of therapy. The MTD for irinotecan administered in combination with cisplatin (30 mg/m(2)) was 50 mg/m(2). The DLTs of this combination were neutropenia and thrombocytopenia. With the addition of amifostine, at an irinotecan dose of 65 mg/m(2) and cisplatin dose of 30 mg/m(2), the DLT was hypocalcemia. Although no objective responses were observed, six patients received at least three courses of therapy. The amounts of platinum adducts (mean +/- SD) were 10 +/- 20 molecules/10(6) nucleotides. The maximum plasma concentrations (C(max)) for free cisplatin and WR-1065 were 4.5 +/- 1.6 micro M and approximately 89 +/- 10 micro M, respectively. The half-life (t(1/2)) for free plasma cisplatin was 25.4 +/- 5.4 min. The initial t(1/2) for plasma WR-1065 was approximately 7 min and terminal t(1/2) approximately 24 min. CONCLUSION: The combination of cisplatin and irinotecan administered weekly for 4 weeks in children with refractory cancer is well tolerated. Amifostine offers some myeloprotection, likely permitting >/=30% dose escalation for irinotecan, when administered in a combination regimen with cisplatin. However, effective antiemetics and calcium supplementation are necessary with the use of amifostine. Further escalation of irinotecan dosing, using these precautions for amifostine administration, may be possible.