Celia Mor

Successful non‐neurotoxic therapy (without radiation) of a multifocal primary brain lymphoma with a methotrexate, vincristine, and BCNU protocol (DEMOB)

A 3.5‐year‐old boy with a multifocal primary lymphoma of the brain was treated successfully without neurotoxicity with a treatment regimen that did not include radiation. The protocol of Dexacort (dexamethasone), methotrexate, Oncovin (vincristine), and BCNU (carmustine) (DEMOB), which was developed with the use of MTX pharmocokinetic studies, was given over 7.5 months, and resulted in tumor disappearance on computerized tomography scans and marked improvement in clinical status. The patient remains in good health 3 years after diagnosis (March 1985).

A novel germ line p53 mutation in intron 6 in diverse childhood malignancies.

Screening for p53 mutations in exons 5 to 8 in 124 pediatric malignancies identified 18 abnormal shifts using single strand conformation polymorphism: 12 were missense mutations and in 6, no mutation was detected in the exon or in the splice donor acceptor sequences. Sequencing was then performed in the adjacent introns, revealing a G to A base substitution at 39 base pairs upstream to exon 7. This mutation was identified in the germ line of five of the patients, and also in the father of one, whose parents were available. For comparison, of the 184 normal controls similarly screened, only one had this mutation (P=0.036). Positive staining of p53 protein was observed in three of the paraffin embedded tissues that were available: brain tumor, rhabdomyosarcoma, and lymphocytes from a normal lymph node from the rhabdomyosarcoma patient. All tumors with the identified intron mutation were Li-Fraumeni syndrome tumors. Sequencing of all exons including splice sites was performed and revealed no mutation. We suggest that this mutation in intron 6 of the p53 gene stabilizes the wild type p53 protein, resulting in its abnormal accumulation. Mutations in the noncoding region of p53 should be further studied.

Clinical relevance of molecular diagnosis in childhood rhabdomyosarcoma.

Rhabdomyosarcoma may be divided into three subtypes--embryonal, alveolar, and undifferentiated sarcoma--which can be distinguished by molecular analysis. The authors applied reverse transcriptase-polymerase chain reaction analysis (RT-PCR) to analyze tumor samples from 14 children with rhabdomyosarcoma for the presence of the chimeric PAX3-FKHR transcript resulting from the translocation t(2;13)(q35,q14). Both fresh and paraffin-embedded tissues were used. In only nine specimens was the RNA intact for the analysis. The chimeric transcript was identified in seven samples: four alveolar type, one embryonal type, and two undifferentiated sarcoma. Histologic review was performed in the three samples with discordance between the molecular and histologic findings. A sample from a patient with a diagnosis of embryonal rhabdomyosarcoma on presentation and expression of PAX3-FKHR fusion transcript yielded a small focus of alveolar rhabdomyosarcoma and was reclassified as alveolar rhabdomyosarcoma. One of the samples from a patient with undifferentiated sarcoma was redefined as alveolar subtype; the diagnosis of the second undifferentiated sarcoma remained unchanged, in accordance with the histologic diagnosis. These findings further support the recommendation that molecular analysis be included in the diagnostic workup of childhood small round cell tumors to reach a more accurate diagnosis for tailoring of specific treatment.

Additional chromosome 1q aberrations and der(16)t(1;16), correlation to the phenotypic expression and clinical behavior of the Ewing family of tumors

The cytogenetic hallmark of the Ewing family of tumors is t(11;22)(q24;q12) in its simple, complex or variant forms and/or its molecular equivalent EWS/FLI, EWS/ERG rearrangement. Additional secondary consistent chromosomal aberrations include the der(16)t(1;16) and, frequently, other chromosome 1q abnormalities leading to 1q overdosage. We studied whether these secondary cytogenetic changes are correlated to clinical features and phenotypic expression which may have a prognostic impact.Successful cytogenetic evaluation was performed in eight patients with a Ewing family tumor. In four of these, in addition to the primary aberration, chromosome 1q overdosage (including two with der(16)t(1;16)) was noted. Out of these four patients, two had metastatic disease at the time of evaluation, while in the other four, disease was localized. Morphologically, the tumors with the additional 1q aberration, revealed the pPNET subtype more frequently than the typical Ewing. They also expressed a higher degree of neural differentiation by neural marker immunocytochemistry, in comparison to tumors without the 1q aberration.Determination of the prognostic significance of this finding requires a longer follow-up with a larger group of patients.

Improved outcome in childhood B-cell lymphoma with the intensified French LMB protocol

BACKGROUND During the last 20 years, 120 children with B cell lymphoma were treated at the National Pediatric Hematology/Oncology Center of Israel. Until 1986, 63 patients received an institutional protocol (BMC), and thereafter 57 patients received a modified French LMB protocol. We report the results of a retrospective analysis comparing the results of these two protocols. PROCEDURE Patient characteristics were similar in both groups except for stage of disease and lactate dehydrogenase (LDH) levels. Significantly more patients in the LMB group had higher stage disease, and the LDH levels also were higher (<600 microg/ml). RESULTS Fifty-four of fifty-seven children on the modified LMB protocol are alive, disease-free, with an overall event-free survival of 94% (median follow-up of 73 months). Event-free survival for stages I, II, and III patients is 100%, and for stage IV 77%, whereas the overall event-free survival was 58% among 63 children treated previously, and for stage IV patients only 10%. Severe marrow suppression and neutropenic enterocolitis were the major complications of this intensive protocol. CONCLUSIONS Intensive chemotherapy with a modified LMB protocol and modern supportive care result in a high cure rate of childhood B cell lymphoma even in patients with advanced disease.

Metastatic extraosseous Ewing tumor: Association of the additional translocation der(16)t(1;16) with the variant EWS/ERG rearrangement in a case of cytogenetically inconspicuous chromosome 22

In Ewing sarcoma and related tumors, recently referred to as the Ewing tumors (ET), t(11;22)(q24q12) and its molecular genetic equivalent, the EWS/FLI-1 rearrangement, characterize approximately 85% of cases, while variant aberrations are rare. A second nonrandom aberration in ET is the unbalanced t(1;16) accompanying the t(11;22) in roughly 17% of cases. We present a 17-year-old man with estraosseous ET and multiple metastases, in whom the only cytogenetically detectable chromosomal aberration was der (16)t(1;16)(q12;q11.2). This finding was confirmed by fluorescence in situ hybridization (FISH). Using the RT-PCR technique, a variant EWS/ERG fusion transcript was noted, resulting from a t(21;22) chromosomal rearrangement which recently demonstrated in roughly 10% of ET. However, data on possible biologic differences in EWS/FLI-1 versus EWS/ERG expressing ET are as yet unavailable. This is the first reported combination of t(1;16) with the EWS/ERG rearrangement. A possible significance of this finding for Ewing tumor progression is discussed.

Eosinophilic Granulomatous Lymphadenopathy: Association with Hyper-IgE and Eosinophilia

Cervical lymph node enlargement is probably the most frequently detected childhood lymphadenopathy. We report 2 cases of cervical lymphadenopathy in children associated with hyper-IgE and eosinophilia, displaying the features of necrotizing eosinophilic granulomatosis. Immunohistochemical analysis and a serological work-up failed to elucidate the underlying etiology. We would like to call the attention of physicians and pathologists to this unusual clinical picture, different from the fatal form of necrotizing eosinophilic granulomatosis, and we suggest a role for the eosinophils in the pathologic appearance of the lymph nodes.