Alessandro Inserra

Features and outcome of neuroblastoma detected before birth

BACKGROUND/PURPOSE The growing use of routine ultrasonography during pregnancy is leading to an increasing number of prenatally diagnosed neuroblastomas. Optimal strategy has not yet been defined for these patients, because knowledge on this particular neuroblastoma (NB) population is still limited. However, definite guidelines are needed to avoid inadequate treatment. The authors analyzed the cases of antenatally detected NB (ADNB) reported in the Italian Neuroblastoma Registry during the past 6 years to elucidate the features of this subset of NB. METHODS The Italian Neuroblastoma Registry was reviewed for the period January 1993 to December 1998 to collect clinical, radiographic, surgical, and histopathological data on ADNB cases. NB stage was evaluated according to INSS criteria. All patients had undergone imaging (computed tomography or magnetic resonance imaging) of the primary tumor and bone marrow biopsy before surgical resection. RESULTS Seventeen patients were identified. Primary tumour site was adrenal glands in 16 cases and retroperitoneal ganglia in 1. Stage distribution was stage I, 13 cases; stage II-A, 1 case; stage II-B, 1 case; stage IV-S, 2 cases. All cases underwent primary tumour resection. Mean age at surgery was 4 weeks. Resection of primary tumor was radical in 16 cases, partial in 1. All tumors were characterised by favourable histology according to Shimada classification. N-myc gene amplification was studied in 14 patients. N-myc amplification was detected only in a newborn with stage II-A NB, who died of massive bleeding 2 days after tumor resection. DNA index and 1p deletion were studied in 11 and 8 patients, respectively. Both diploidy and deletion of 1p were observed in a newborn who subsequently died of disease progression despite surgery, chemotherapy, and radiation therapy. Fourteen of 17 patients currently are alive and free of disease, and one with IV-S NB and short follow-up is alive with disease. CONCLUSIONS Our data give evidence that in most cases infants with ADNB represent a subset of patients with excellent outcome. Aggressive treatment may not always be necessary. Infants with ADNB with unfavorable features should undergo early surgical excision, whereas patients with favourable features could be observed awaiting spontaneous regression of the mass, reserving delayed surgery for tumors that increase in size or do not regress.

Malignant Pancreatic Endocrine Tumor in a Child With Tuberous Sclerosis

Tuberous sclerosis complex (TSC) is an autosomal dominant condition whose signs and symptoms may vary from a few hypopigmented skin spots to epilepsy, severe mental retardation, and renal failure. The disease is caused by mutations in either TSC1 or TSC2 gene, at chromosome 9q34 and 16p13.3. Inactivation of both alleles at TSC1 or TSC2 loci is associated with the development of hamartomas in different organs, and only rarely with malignant neoplasms. In this study we present a 6-year-old boy with TSC and with a malignant islet cell tumor of the pancreas. Mutation analysis of DNA extracted from peripheral blood cells of the patient identified an R1459X de novo mutation in exon 33 of the TSC2 gene. Immunohistochemical analysis with anti-tuberin antibodies on paraffin-embedded tissue sections showed loss of tuberin immunostaining in tumor cells but normal expression in residual normal pancreas. DNA analysis of tumor and normal cells showed chromosome 16p13 loss of heterozygosity in malignant pancreatic islet cell tumor but not in normal pancreas. These findings suggest a role for tuberin, the TSC2 gene product, in the pathogenesis of malignant pancreatic endocrine tumor.

Isolated tubal torsion: a rare cause of pelvic pain at menarche. Sonographic and MR findings

Isolated torsion of the fallopian tube is a rare clinical entity, especially in adolescents and at menarche. The diagnosis is essentially made at laparoscopy or at laparotomy because of nonspecific clinical signs. We present a case of isolated tubal torsion in a 12-year-old girl a few days after menarche, highlighting the sonographic and MR findings. Both techniques demonstrated the enlarged and tortuous fallopian tube with normal ovaries and uterus, but MR was also able to characterize contained blood and absent vascular supply. Although this condition is uncommon it should be considered as a cause of acute pelvic pain in adolescents because of the possibility of salvage surgery with early diagnosis. Sonography and MRI have a complementary role in this diagnosis.

Ifosfamide/carboplatin/etoposide (ICE) as front-line, topotecan/ cyclophosphamide as second-line and oral temozolomide as third-line treatment for advanced neuroblastoma over one year of age

Children affected by advanced neuroblastoma have a discouraging prognosis, but intensive induction chemotherapy may increase the complete response rate. The combination of ifosfamide, carboplatin and etoposide (ICE) was used for the first time as front‐line regimen in patients with stage 4 neuroblastoma over the age of 1 y. Similarly, second‐line treatment for children with relapsed neuroblastoma, particularly after high‐dose chemotherapy, has been unsatisfactory. The combination of topotecan and cyclophosphamide was studied in resistant or relapsed solid tumors. Furthermore, there is a need for effective palliative treatment in patients failing therapy. Temozolomide, a new dacarbazine analog with optimal oral bioavailability, is being used in an ongoing phase II study as an alternative to oral etoposide. Seventeen patients with stage 4 neuroblastoma have entered the ICE study; 15/16 (94%) major responses after induction were observed and 6/16 (37%) evaluable patients are disease free after a median of 51 mo. Twenty‐one patients with relapsed/refractory disease (of whom 13 neuroblastomas) entered the topotecan/cyclophosphamide study: 7/21 (33%) patients responded. Forty‐one patients entered the temozolomide study (of whom 16 had neuroblastomas): stable disease and symptom relief were obtained in 15/30 (50%) evaluable patients. Intensive induction with ICE resulted in a faster response with high response rate; a larger study with longer follow‐up is needed to confirm a survival advantage. Second‐line treatment was effective in obtaining remissions, some of them long lasting. Third‐line treatment did not elicit measurable responses in neuroblastoma, but achieved prolonged freedom from disease progression and excellent palliation in several patients.

Evaluating Access to Pediatric Cancer Care Centers of Children and Adolescents With Rare Tumors in Italy: The TREP Project

A national project focusing on rare malignant pediatric tumors (the TREP project) was launched in Italy in 2000. The present study compared the number of these tumors expected to be diagnosed in Italy with the number of cases actually enrolled in the TREP database in 2000–2006.

The Polycomb group (PcG) protein EZH2 supports the survival of PAX3-FOXO1 alveolar rhabdomyosarcoma by repressing FBXO32 (Atrogin1/MAFbx)

The Polycomb group (PcG) proteins regulate stem cell differentiation via the repression of gene transcription, and their deregulation has been widely implicated in cancer development. The PcG protein Enhancer of Zeste Homolog 2 (EZH2) works as a catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) by methylating lysine 27 on histone H3 (H3K27me3), a hallmark of PRC2-mediated gene repression. In skeletal muscle progenitors, EZH2 prevents an unscheduled differentiation by repressing muscle-specific gene expression and is downregulated during the course of differentiation. In rhabdomyosarcoma (RMS), a pediatric soft-tissue sarcoma thought to arise from myogenic precursors, EZH2 is abnormally expressed and its downregulation in vitro leads to muscle-like differentiation of RMS cells of the embryonal variant. However, the role of EZH2 in the clinically aggressive subgroup of alveolar RMS, characterized by the expression of PAX3-FOXO1 oncoprotein, remains unknown. We show here that EZH2 depletion in these cells leads to programmed cell death. Transcriptional derepression of F-box protein 32 (FBXO32) (Atrogin1/MAFbx), a gene associated with muscle homeostasis, was evidenced in PAX3-FOXO1 RMS cells silenced for EZH2. This phenomenon was associated with reduced EZH2 occupancy and H3K27me3 levels at the FBXO32 promoter. Simultaneous knockdown of FBXO32 and EZH2 in PAX3-FOXO1 RMS cells impaired the pro-apoptotic response, whereas the overexpression of FBXO32 facilitated programmed cell death in EZH2-depleted cells. Pharmacological inhibition of EZH2 by either 3-Deazaneplanocin A or a catalytic EZH2 inhibitor mirrored the phenotypic and molecular effects of EZH2 knockdown in vitro and prevented tumor growth in vivo. Collectively, these results indicate that EZH2 is a key factor in the proliferation and survival of PAX3-FOXO1 alveolar RMS cells working, at least in part, by repressing FBXO32. They also suggest that the reducing activity of EZH2 could represent a novel adjuvant strategy to eradicate high-risk PAX3-FOXO1 alveolar RMS.

Asymptomatic congenital cystic adenomatoid malformation of the lung: Is it time to operate?

OBJECTIVE The optimal management of congenital adenomatoid malformation of the lung remains controversial. Prenatal ultrasonographic analysis has increasingly discovered asymptomatic lesions, raising questions about the need for and timing of surgical treatment for asymptomatic congenital adenomatoid malformation. The aim of our study was to analyze the short-term postoperative outcome of symptomatic congenital adenomatoid malformations compared with asymptomatic malformations. METHODS All the data of patients presenting with congenital adenomatoid malformations histologically diagnosed and operated on between 1998 and 2005 at our institution were retrospectively reviewed. Patients were divided into 2 groups: group A comprised asymptomatic infants, and group B comprised symptomatic infants. Major outcomes considered were the length of ventilation, pleural drainage, and hospital stay. Postoperative morbidity and mortality were also evaluated. Asymptomatic patients were further stratified for age at the time of the operation to evaluate whether age at surgical intervention affects the outcome. The Fishers exact and Mann-Whitney tests were used as appropriate. RESULTS Fifty-seven patients were consecutively treated. Thirty-five patients were given diagnoses of asymptomatic lesions and were enrolled into group A, whereas 22 patients presenting with symptoms were entered into group B. The lengths of ventilation, pleural drainage, and hospital stay were significantly longer in patients with symptomatic congenital adenomatoid malformations. Moreover, symptomatic patients presented with a higher postoperative complication rate. The age-based stratification of asymptomatic children did not show any difference on either postoperative mortality or major outcome considered. CONCLUSION Children with congenital adenomatoid malformations operated on when asymptomatic present a better short-term outcome than symptomatic children. In addition, age at the time of the operation does not negatively affect the outcome. Our findings support early surgical treatment for asymptomatic congenital adenomatoid malformation.

Inflammatory myofibroblastic tumors in childhood: a report from the Italian Cooperative Group studies.

Inflammatory myofibroblastic tumors (IMTs) are myofibroblastic lesions with unpredictable biologic behavior that occur at a young age. For this report, the authors investigated clinicopathologic features in a series of pediatric IMTs. The objective of the study was to identify morphologic or immunohistochemical prognostic markers and the possible pathogenic role of human herpes virus 8 (HHV‐8).

Clinical Significance of CXC Chemokine Receptor-4 and c-Met in Childhood Rhabdomyosarcoma

Purpose: The CXC chemokine receptor-4 (CXCR4)/stromal-derived factor-1 and c-Met/hepatocyte growth factor axes promote the metastatic potential of rhabdomyosarcoma cell lines in experimental models, but no data are available on their role in rhabdomyosarcoma tumors. The expressions of CXCR4 and c-Met were evaluated in primary tumors and isolated tumor cells in marrow, and were correlated with clinicopathologic variables and survival. Experimental Design: Forty patients with recently diagnosed rhabdomyosarcoma were retrospectively enrolled. CXCR4 and c-Met expression was investigated in primary tumors by immunohistochemistry, in isolated marrow-infiltrating tumor cells using double-label immunocytology. Results were expressed as the mean percentage of immunostained tumor cells. Results: CXCR4 and c-Met were expressed in ≥5% of tumor cells from 40 of 40 tumors, with 14 of 40 cases showing ≥50% of immunostained tumor cells (high expression). High CXCR4 expression correlated with alveolar histology (P = 0.006), unfavorable primary site (P = 0.009), advanced group (P < 0.001), marrow involvement (P = 0.007), and shorter overall survival and event-free survival (P < 0.001); high c-Met expression correlated with alveolar histology (P = 0.005), advanced group (P = 0.04), and marrow involvement (P = 0.02). In patients with a positive diagnosis for isolated tumor cells in marrow (n = 16), a significant enrichment in the percentage of CXCR4-positive (P = 0.001) and c-Met–positive (P = 0.003) tumor cells was shown in marrow aspirates compared with the corresponding primary tumors. Conclusions: CXCR4 and c-Met are widely expressed in both rhabdomyosarcoma subtypes and, at higher levels, in isolated marrow-infiltrating tumor cells. High levels of expression are associated with unfavorable clinical features, tumor marrow involvement and, only for CXCR4, poor outcome. In rhabdomyosarcoma, CXCR4 and c-Met represent novel exploitable targets for disease-directed therapy.

Preserved antibody levels and loss of memory B cells against pneumococcus and tetanus after splenectomy: Tailoring better vaccination strategies

Splenectomized patients are exposed to an increased risk of septicemia caused by encapsulated bacteria. Defense against infection is ensured by preformed serum antibodies produced by long‐lived plasma cells and by memory B cells that secrete immunoglobulin in response to specific antigenic stimuli. Studying a group of asplenic individuals (57 adults and 21 children) without additional immunologic defects, we found that spleen removal does not alter serum anti‐pneumococcal polysaccharide (PnPS) IgG concentration, but reduces the number of PnPS‐specific memory B cells, of both IgM and IgG isotypes. The number of specific memory B cells was low in splenectomized adults and children that had received the PnPS vaccine either before or after splenectomy. Seven children were given the 13‐valent pneumococcal conjugated vaccine after splenectomy. In this group, the number of PnPS‐specific IgG memory B cells was similar to that of eusplenic children, suggesting that pneumococcal conjugated vaccine administered after splenectomy is able to restore the pool of anti‐PnPS IgG memory B cells. Our data further elucidate the crucial role of the spleen in the immunological response to infections caused by encapsulated bacteria and suggest that glycoconjugated vaccines may be the most suitable choice to generate IgG‐mediated protection in these patients.