Asim Yoruk

TREATMENT OF WILMS TUMOR: A Report from the Turkish Pediatric Oncology Group (TPOG)

Aim: To standardize diagnosis and treatment of childhood Wilms tumor (WT) in Turkey. Methods and patients: Between 1998 and 2006, WT patients were registered from 19 centers. Patients <16 years with unilateral WT whose treatment started in first postoperative 3 weeks were included. Treatments were stage I favorable (FH) and unfavorable histology (UH) patients, VCR + Act-D; stage IIA FH, VCR + Act-D; stage IIB FH, VCR + Act-D + radiotherapy (RT); stage III–IV FH, VCR + Act-D + adriamycin (ADR) + RT; stages II–IV UH tumors, VCR + Act-D + ADR + etoposide + RT. Results: 165/254 registered cases were eligible (bilateral, 5.9%) [median age 3.0 years; M/F: 0.99; 50/165 cases ≤2 years]. 9.7% cases had UH tumors. Disease stages were stage I 23.6%; IIA 36.4%; IIB 5.5%; III 22.4%; IV 12.1%. Cases >2 years had significantly more advanced disease. 1/11 cases with recurrent disease died; 2/165 had progressive disease, 2/165 had secondary cancers, and all 4 died. In all cases 4-year OS and EFS were 92.8 and 86.5%, respectively. Both OS and EFS were significantly worse in stage IV. Conclusions: Despite problems in patient management and follow-up, treatment results were encouraging in this first national experience with a multicentric study in pediatric oncology. Revisions and modifications are planned to further improve results and minimize short- and long-term side effects.

Seroconversion Status After Single Dose and Double Doses of Varicella Vaccination in Children With Leukemia

Although varicella is a benign self-limiting disease in healthy children, it can be fatal when it occurs in immunocompromised hosts. Despite that immunosuppressed children are suggested to require 2 doses of vaccine to achieve seroconversion, conflicting results are reported in the literature. The aim of this study was to investigate the seroconversion status and mean antibody titers at first year after single dose and double doses of varicella vaccination in acute lymphoblastic leukemia patients. Patients with leukemia in remission for at least 1 year who were seronegative for varicella-zoster virus immunoglobulin G (IgG) were vaccinated. Titers above the cutoff level (0.65) were accepted as seroconversion. Seventeen patients were vaccinated with single dose whereas 24 patients were vaccinated with double doses. Mean prevaccination antibody titers were 0.56 ± 0.05 in patients with single dose and 0.51 ± 0.08 in patients with double doses (P > .05, Student t test). The mean antibody titers at first year were 0.61 ± 0.05 in patients with single-dose vaccination (P > .05, Wilcoxon signed-rank test) and 1.48 ± 0.04 in patients with double doses (P < .001, Wilcoxon signed-rank test). Seroconversion after single-dose vaccination was achieved in 29% of patients (n = 5/17) and in 75% of patients with double doses (n = 18/24) at first year (P = .004, chi-square test). These results suggest that seroconversion after single-dose vaccination might not persist at first year in malignancy patients. Double doses should be applied in order to provide long-term seroconversion.

Adult type granulosa cell tumor causing precocious pseudopuberty in a 6 year-old girl.

Malignant ovarian tumors are responsible for 2-3% of all cases of precocious pseudopuberty (PP) in girls. The most common forms of ovarian tumors presenting as PP are the granulosa cell tumors (GCT). The clinical and pathological features of granulosa cell tumors that occur frequently in young girls, so-called juvenile granulosa cell tumors (JGCT), differ histologically from those occurring in adults. As a cause of PP in young girls, adult type granulosa cell tumors (AGCT) are extremely rare. We report a 6 year-old girl presenting with early breast development and vaginal bleeding due to a well encapsulated ovarian tumor. Microscopic features of the resected tumor were characteristic of AGCT.

Myeloid Sarcoma Presenting with Leukemoid Reaction in a Child Treated for Acute Lymphoblastic Leukemia

Background. Myeloid sarcoma is an extramedullary neoplasm of immature myeloid cells. Our study reports a presentation of myeloid sarcoma which presented with severe leukemoid reaction as a secondary malignancy in a patient who was treated for acute lymphoblastic leukemia previously. The case emphasizes the difficulties in diagnosis of patients who do not have concomitant leukemia. Case Presentation. A 6-year-old girl who was treated for acute lymphoblastic leukemia previously presented with fatigue, paleness, and hepatosplenomegaly. Peripheral blood smear and bone marrow aspirate examination did not demonstrate any blasts in spite of severe leukemoid reaction with a white cell count 158000/mm3. FDG/PET CT revealed slight uptake in cervical and supraclavicular lymph nodes. Excisional lymph node biopsy was performed from these lymph nodes and it showed myeloid sarcoma. Conclusion. Myeloid sarcoma can develop as a secondary malignancy in children who are treated for acute lymphoblastic leukemia. It can be associated with severe leukemoid reaction and diagnosis may be difficult if there is not concomitant leukemia. PET/CT is helpful in such cases.

A trombosis story and PRES

Trombosis is seen in children with acute lymphoblastic leukemia during or after L-asparaginase treatment. Posterior reversible encephalopathy syndrome (PRES) is a complex syndrome characterized with sudden hypertension, headache, nausea, vomiting, alteration in the state of consciousness, vision defect and seizures. The cases related to this syndrome have been reportedly seen after eclampsia, organ transplantation, immunsuppressive treatments, autoimmune diseases and chemotherapy. Vasogenic edema occuring in the brain parencyhma constitues the basic pathophysiology. We present a case who developed seizures during treatment for B-cell acute lymphoblastic leukemia and diagnosed as posterior reversible encephalopathy.