All children with malignant rhabdoid tumors should be treated initially with intensive chemotherapy

Malignant rhabdoid tumors (MRT) of soft tissues are aggressive tumors, which can be detected in almost any part of the body. MRT are rare, and very few cases have been reported in the literature. Prognosis of these tumors is extremely poor despite intensive therapy. Some risk factors such as young age or disseminated disease are associated with an aggressive and almost always lethal clinical course. Some clinicians even recommend initial palliative care due to this outcome. We report a case of metastatic MRT in a 6-month-old child with excellent initial response to chemotherapy.

[Transformation of myelodysplastic syndrome to acute lymphoblastic leukemia: 2 new cases]

Myelodysplastic syndromes (MDS) are clonal disorders of hematopoietic stem cells, with a variable risk of transformation to acute myeloid leukemia. Progression into acute lymphoblastic leukemia (ALL) is an extremely rare event, with very few cases published in children. In this report, we describe two cases of myelodysplastic syndromes that progressed to ALL. Moreover, we review previously reported cases of MDS transformation to acute lymphoblastic leukemia in the pediatric population whose prognosis seems to be similar to that for adults.

Efficacy and safety of liposomal cytarabine in children with primary CNS tumours with leptomeningeal involvement

PURPOSE

To assess the efficacy and safety of liposomal cytarabine in the treatment of de novo and relapsed leptomeningeal involvement in children with primary CNS tumours.

METHODS

Data from clinical charts were entered into a database for consecutive unselected patients (n=20) from nine Spanish centres. Diagnosis of leptomeningeal involvement was confirmed by cytology, MRI and/or CT scan. The dose of liposomal cytarabine used varied from 20 to 50 mg, by age.

RESULTS

There were 8 females and 12 males, mean age 7.3 years (range 8 months to 18 years). The tumours were: 10 medulloblastomas, 4 ependymomas, 3 primitive neuroectodermal tumours and 3 other tumours. Fourteen had undergone previous chemotherapy and 12 radiotherapy. Nine received concurrent chemotherapy and 2 concurrent radiotherapy. Median follow-up was 244.5 days (range 12- 869). Patients received a median of 5 doses (range 1-9) of liposomal cytarabine. A neurological response (complete or partial) was seen in 11/19 (58%) and a cytological response in 7/10 (64%). Median time to neurological progression exceeded 180 days (range 12-869). Adverse effects were reported in 11/20 patients, but none was grade IV.

DISCUSSION

Liposomal cytarabine was well tolerated and efficacious in this patient group, but prospective randomised trials are needed.

Treatment of metastatic neuroblastoma with systemic oncolytic virotherapy delivered by autologous mesenchymal stem cells: an exploratory study

Treatment of metastatic tumors with engineered adenoviruses that replicate selectively in tumor cells is a new therapeutic approach in cancer. Systemic administration of these oncolytic adenoviruses lack metastatic targeting ability. The tumor stroma engrafting property of intravenously injected mesenchymal stem cells (MSCs) may allow the use of MSCs as cellular vehicles for targeted delivery. In this work, we study the safety and the efficacy of infusing autologous MSCs infected with ICOVIR-5, a new oncolytic adenovirus, for treating metastatic neuroblastoma. Four children with metastatic neuroblastoma refractory to front-line therapies received several doses of autologous MSCs carrying ICOVIR-5, under an approved preliminary study. The tolerance to the treatment was excellent. A complete clinical response was documented in one case, and the child is in complete remission 3 years after this therapy. We postulate that MSCs can deliver oncolytic adenoviruses to metastatic tumors with very low systemic toxicity and with beneficial antitumor effects.

PBSC collection in extremely low weight infants: a single-center experience

BACKGROUND

Peripheral blood progenitor cell (PBPC) collection has become the main source of hematopoietic cells for high-dose chemotherapy with stem cell rescue and, in some protocols, for allogeneic hematopoietic transplantation. This procedure is complicated in the smallest children because of difficulties related to their weight, and there is little published experience. We have conducted a prospective study to analyze the incidence of adverse events during PBPC collection in the smallest children (< or = 10 kg).

METHODS

From January 2000 to November 2005, 257 leukapheresis were performed in our unit, and 13 of them (5%) in 12 children weighing up to 10 kg (median 9 kg, range 5.8-10.9 kg).

RESULTS

Most cases had hypovolemic signs during the procedure (usually tachycardia); six cases had hypotension, five of them with pallor and diaphoresis, and, of those, two also had nausea. In all these cases infusion of saline or plasma volume expanders resolved the clinical findings. In two cases the nausea related to hypocalcemia was resolved after calcium gluconate infusion. Changes in platelet counts were also remarkable, with a median platelet loss of 52%.

DISCUSSION

Leukapheresis with continuous-flow cell separators has frequent complications related to volume shift in the smallest children. These adverse events are mild and easily resolved with standard measures for hypovolemia, as plasma expander or normal saline infusions. However, we recommend that the procedure should only be performed by teams with extensive experience in the field.