A Case of Relapsed Medulloblastoma Treated with Intensity-Modulated Radiotherapy and Temozolomide

We report a case of relapsed high-risk non-metastatic medulloblastoma in a 14-year-old boy, which was treated with intensity-modulated radiotherapy (IMRT) and temozolomide (TMZ). At the age of 11, the patient underwent an MRI-confirmed incomplete resection of a fourth-ventricle medulloblastoma, followed by conventional chemotherapy, craniospinal irradiation (55.8 Gy, 1.8 Gy/fraction) and then myeloablative chemotherapy followed by peripheral blood progenitor cell rescue. After 18 months of complete remission following the completion of chemotherapy, MRI showed a 2.5-cm mass in the olfactory notch. The patient underwent IMRT (45 Gy, 1.8 Gy/fraction) with concomitant administration of TMZ (180 mg/m2, 5 days every 21 days), which was well tolerated. After 5 cycles of TMZ, MRI showed complete remission with no evidence of the mass. TMZ was continued for another 5 cycles and then stopped. At 14 months from the completion of IMRT, a new MRI scan showed multiple nodular relapses around the fourth ventricle and the patient is currently treated with oral etoposide.

Evaluation of platelet turnover by flow cytometry

The number of circulating newly produced platelets depends on the thrombopoietic capacity of bone marrow as well as platelet removal from the bloodstream. Flow cytometric analysis with thiazole orange (TO), a fluorescent dye that crosses platelet membranes and binds intracellular RNA, has been used to measure circulating reticulated platelets (RPs) with high RNA content as an index of platelet turnover. We first assessed the specificity of TO flow cytometry and then applied this method in the diagnosis of thrombocytopenia caused by impaired platelet production or increased destruction. We also explored the utility of TO flow cytometry to predict thrombocytopoiesis after chemotherapy-induced bone marrow aplasia. Venous blood, anticoagulated with K(2)EDTA, was incubated with 0.6 microg/ml TO plus an anti-GPIIIa monoclonal antibody. The mean percentage of RPs in control subjects (n = 23) was 6.13 +/- 3.09%. RPs were 10.41 +/- 9.02% in patients (n = 10) with hematological malignancies during aplasia induced by chemotherapy and a significant increase in RPs (35.45 +/- 6.11%) was seen in the recovery phase. In 10 patients with idiopathic thrombocytopenic purpura, the percentage of TO positive platelets was 67.81 +/- 18.79 (P < 0.001 vs. controls). In patients with thrombocytopenia associated with hepatic cirrhosis (n = 21; 21.04 +/- 16.21%, P < 0.001 vs. controls) or systemic lupus erythematosus (n = 6, 29.08 +/- 15.57%; P < 0.001 vs. controls) increases in TO-stained platelets were also observed. Measurement of TO positive platelets may be a reliable tool for the laboratory identification of platelet disorders, with a higher sensitivity than measurement of platelet volume. Measurement of RPs may also prove useful to recognize the underlying pathogenetic mechanisms in thrombocytopenia.

Familial haemophagocytic lymphohistiocytosis: survival of a premature twin with immuno-chemotherapy and bone marrow transplantation from an HLA-identical unrelated donor

We describe a premature twin born at 30 wk of gestational age, affected with familial haemophagocytic lymphohistiocytosis. Two different mutations were identified in his DNA: one inherited from the mother and one from the father. Haemophagocytosis had been confirmed in his twin brother, who died soon after birth, as well as in the re-evaluation of the autopsy of his older sister, who died 1 y earlier. At 26 d of age, chemotherapy and immune-suppressive treatment were started according to the HLH-94 protocol. At 6 mo of age, a bone marrow transplant from an HLA-identical, unrelated volunteer was performed. Now at 32 mo of age, the infant is healthy and without signs of graft-versus-host disease.

CONCLUSION

This case report shows that immuno-chemotherapy and allogenic bone marrow transplant are feasible even in premature infants affected with familial haemophagocytic lymphohistiocytosis, which should be ruled out in unknown bleeding disorders of neonates.

Growth hormone response following growth hormone releasing hormone injection in thalassemia major: influence of pubertal development

Thirty-five patients with thalassemia major, aged 7 to 21 years, were studied to define the relationship between the pubertal development and the growth-hormone (GH) secretion during sleep, after administration of GH-releasing factor (hpGRF 1-44), and betaxolol-glucagon or arginin-insulin. Pubertal development was classified as being appropriate or delayed for chronological age. GH response to pharmacological stimuli and during sleep was not linked to the pubertal development according to the chronological age. The peak of GH secretion after GHRH injection was significantly delayed in thalassemic patients with retarded puberty. The integrated secretion of GH during the 120-min test was slightly but not significantly reduced in these patients. The prepubertal pattern of GHRH response was restored in the patients receiving substitutive therapy by HCG or testosterone. The alteration of GH response to GHRH in thalassemic patients is likely to be only due to delayed puberty and decreased endogeneous GHRH secretion since it is corrected by androgen or gonadotropin replacement.