Phase I and Pharmacology Study of Ropidoxuridine (IPdR) as Prodrug for Iododeoxyuridine-Mediated Tumor Radiosensitization in Advanced GI Cancer Undergoing Radiation.

PURPOSE: Iododeoxyuridine (IUdR) is a potent radiosensitizer; however, its clinical utility is limited by dose-limiting systemic toxicities and the need for prolonged continuous infusion. 5-Iodo-2-pyrimidinone-2'-deoxyribose (IPdR) is an oral prodrug of IUdR that, compared with IUdR, is easier to administer and less toxic, with a more favorable therapeutic index in preclinical studies. Here, we report the clinical and pharmacologic results of a first-in-human phase I dose escalation study of IPdR + concurrent radiation therapy (RT) in patients with advanced metastatic gastrointestinal (GI) cancers. PATIENTS AND METHODS: Adult patients with metastatic GI cancers referred for palliative RT to the chest, abdomen, or pelvis were eligible for study. Patients received IPdR orally once every day × 28 days beginning 7 days before the initiation of RT (37.5 Gy in 2.5 Gy × 15 fractions). A 2-part dose escalation scheme was used, pharmacokinetic studies were performed at multiple time points, and all patients were assessed for toxicity and response to Day 56. RESULTS: Nineteen patients were entered on study. Dose-limiting toxicity was encountered at 1,800 mg every day, and the recommended phase II dose is 1,200 mg every day. Pharmacokinetic analyses demonstrated achievable and sustainable levels of plasma IUdR ≥1 µmol/L (levels previously shown to mediate radiosensitization). Two complete, 3 partial, and 9 stable responses were achieved in target lesions. CONCLUSIONS: Administration of IPdR orally every day × 28 days with RT is feasible and tolerable at doses that produce plasma IUdR levels ≥1 µmol/L. These results support the investigation of IPdR + RT in phase II studies.

Myelomastocytic Leukemia With t(8;21) in a 3-year-old Child.

Here we report a 3-year-old boy with myelomastocytic leukemia. The patient presented with fatigue and right eye proptosis. Bone marrow revealed acute myeloid leukemia with t(8;21) and trisomy 8. Induction therapy produced marked reduction in marrow myeloblasts with the emergence of 13% atypical mast cells. These cells were subsequently identified in retrospect in the diagnostic marrow consistent with myelomastocytic leukemia. His clinical course was notable for the difficulty in the eradication of the leukemic process and resembled that of adults with systemic mastocytosis with associated hematologic non-mast cell lineage disease. To the best of our knowledge, this is the youngest individual reported. The implications of mast cell lineage involvement in acute myeloid leukemia are reviewed.

Acute hemolytic transfusion reaction in a pediatric patient following transfusion of apheresis platelets.

The practice of transfusing ABO-incompatible platelets, driven primarily by concerns about inventory management, has been considered generally safe because the accompanying plasma is usually diluted in the recipient's total blood volume. However, if the platelet product contains a large volume of plasma or a high concentration of incompatible isoagglutinin, there may be hemolysis of the recipient's red cells. Patients with a small blood volume, such as babies and children, are considered to be at particular risk for such a complication. We describe the case of a baby who suffered massive hemolysis of her group A red cells after transfusion of group O Apheresis Platelets containing a high-titered anti-A isoagglutinin. We also offer a review of the literature on this subject and recommendations to avoid acute hemolytic reactions as a result of platelet transfusion.

Fatal congenital systemic juvenile xanthogranuloma with liver failure.

This is the second reported patient with systemic juvenile xanthogranuloma (JXG) to die with liver failure. The infant was born with multiple skin lesions and mild hepatomegaly. Direct hyperbilirubinemia was noted on the 2nd day of life, followed by progressive hepatomegaly, cholestasis, and death at 29 days of age. At autopsy, nodular tumor infiltrates of JXG were present throughout the liver, as well as in skin, abdominal lymph nodes, spleen, and pancreas.

Phase I trial of cisplatin and topotecan in children with recurrent solid tumors: Children's Cancer Group Study 0942.

OBJECTIVES: To determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of cisplatin after a 72-hour continuous infusion of topotecan. PATIENTS AND METHODS: Thirty-six children younger than age 22 years (range 3-21) with recurrent solid tumors were treated with cisplatin 45 to 75 mg/m2 infused over the course of 6 hours, followed by a 72-hour continuous infusion of topotecan 0.75 or 1 mg/m2 per day, followed by granulocyte colony stimulating factor (G-CSF), either immediately after treatment or when neutropenia developed. Patients were stratified by the presence of bone marrow tumor involvement and previous radiation to the bone marrow. RESULTS: The DLT was neutropenia (absolute neutrophil count <500/microL for >7 days). The MTD was cisplatin 60 mg/m2 and topotecan 1 mg/m2 per day followed by G-CSF starting 24 hours after chemotherapy for patients without marrow involvement or previous radiation to the bone marrow. An acceptable MTD was not found for patients with previous radiation to the bone marrow or bone marrow involvement or without the use of G-CSF starting 24 hours after chemotherapy was completed. Topotecan clearance and steady-state levels were determined. Limited evidence for antitumor activity with this combination was found in rhabdomyosarcoma. CONCLUSIONS: The recommended dose for phase II trials is cisplatin 60 mg/m2 followed by a 72-hour infusion of topotecan 1 mg/m2 per day with G-CSF starting 24 hours after the completion of topotecan.