Mass screening for neuroblastoma: quo vadis? A 9-year experience from the Pediatric Oncology Study Group of the Kyushu area in Japan

Comparison of Stage 4 and Stage 4s Neuroblastoma Identifies Autophagy-Related Gene and LncRNA Signatures Associated With Prognosis

Background: The spontaneous regression of neuroblastoma (NB) is most prevalent and well-documented in stage 4s NB patients. However, whether autophagy plays roles in the spontaneous regression of NB is unknown. Objective: This study aimed to identify autophagy-related genes (ARGs) and autophagy-related long non-coding RNAs (lncRNAs) differentially expressed in stage 4 and stage 4s NB and to build prognostic risk signatures on the basis of the ARGs and autophagy-related lncRNAs. Methods: One RNA-sequence (RNA-Seq) dataset (TARGET NBL, n = 153) was utilized as discovery cohort, and two microarray datasets (n = 498 and n = 223) were used as validation cohorts. Differentially expressed ARGs were identified by comparing stage 4s and stage 4 NB samples. An ARG signature risk score and an autophagy-related lncRNA signature risk score were constructed. The receiver operating characteristic (ROC) curve analyses were used to evaluate the survival prediction ability of the two signatures. Gene function annotation and Gene Set Enrichment Analysis (GSEA) were performed to clarify the autophagic biological processes enriched in different risk groups. Results: Nine ARGs were integrated into the ARG signature. Patients in the high-risk group of the ARG signature had significantly poorer overall survival (OS) than patients in the low-risk group. The ROC curves analyses revealed that the ARG signature performed very well in predicting OS [5-year area under the curve (AUC) = 0.81]. Seven autophagy-related lncRNAs were integrated into the autophagy-related lncRNA signature. Patients in the high-risk group of the lncRNA signature had significantly poorer OS than patients in the low-risk group. The ROC curve analyses also revealed that the lncRNA signature performed well in predicting OS (5-year AUC = 0.77). Both the ARG signature and lncRNA signature are independent with other clinical risk factors in the multivariate Cox regression survival analyses. GSEAs revealed that autophagy-related biological processes are enriched in low-risk groups. Conclusions: Autophagy-related genes and lncRNAs are differentially expressed between stage 4 and stage 4s NB. The ARG signature and autophagy-related lncRNA signature successfully stratified NB patients into two risk groups. Autophagy-related biological processes are highly enriched in low-risk NB groups.

Combined analysis of RNA-sequence and microarray data reveals effective metabolism-based prognostic signature for neuroblastoma

The relationship between metabolism reprogramming and neuroblastoma (NB) is largely unknown. In this study, one RNA‐sequence data set (n = 153) was used as discovery cohort and two microarray data sets (n = 498 and n = 223) were used as validation cohorts. Differentially expressed metabolic genes were identified by comparing stage 4s and stage 4 NBs. Twelve metabolic genes were selected by LASSO regression analysis and integrated into the prognostic signature. The metabolic gene signature successfully stratifies NB patients into two risk groups and performs well in predicting survival of NB patients. The prognostic value of the metabolic gene signature is also independent with other clinical risk factors. Nine metabolism‐related long non‐coding RNAs (lncRNAs) were also identified and integrated into the metabolism‐related lncRNA signature. The lncRNA signature also performs well in predicting survival of NB patients. These results suggest that the metabolic signatures have the potential to be used for risk stratification of NB. Gene set enrichment analysis (GSEA) reveals that multiple metabolic processes (including oxidative phosphorylation and tricarboxylic acid cycle, both of which are emerging targets for cancer therapy) are enriched in the high‐risk NB group, and no metabolic process is enriched in the low‐risk NB group. This result indicates that metabolism reprogramming is associated with the progression of NB and targeting certain metabolic pathways might be a promising therapy for NB.

Identification of prognostic long noncoding RNAs associated with spontaneous regression of neuroblastoma

Background

The association between long noncoding RNAs (lncRNAs) and spontaneous regression of neuroblastoma (NB) has rarely been investigated and remains unknown.

Objective

To identify prognostic lncRNAs involved in the spontaneous regression of NB.

Methods

Differential expression analyses were performed between those samples with an outcome of death in stage 4 NB group and those samples with an outcome of survival in stage 4S NB group in two independent public datasets, respectively. Univariate Cox proportional hazard regression survival analysis was performed in each of the entire cohort to identify those lncRNAs significantly associated with overall survival (OS). Those lncRNAs independently associated with OS were then identified by multivariate Cox survival analysis and used to construct an lncRNA risk score.

Results

A total of 20 differentially expressed and survival‐related lncRNAs were identified sharing between the two independent cohorts. The expression of each of these 20 lncRNAs was significantly correlated with the expression of NTRK1, which is a well‐known factor involved in NB spontaneous regression. Four lncRNAs (LNC00839, FIRRE, LOC283177, and LOC101928100) were identified to be significantly associated with survival independent with each other and a four‐lncRNA signature risk score was constructed. Patients with high lncRNA signature risk score had a significantly poorer OS and event‐free survival than those with low lncRNA signature risk score. The four‐lncRNA signature has a good performance in predicting survival independent with MYCN amplification (nonamplified vs amplified), age status (<18 months vs ≥18 months), risk status (low risk vs high risk), and International Neuroblastoma Staging System (INSS) stage (INSS 1/2/3/4S vs INSS 4).

Conclusions

We identified 20 survival‐related lncRNAs that might be associated with the spontaneous regression of NB and developed a four‐lncRNA signature risk score. The four‐lncRNA signature is an independent prognostic factor for survival of NB patients.

Neuroblastoma

Neuroblastoma is one of the most common solid tumors in children and has a diverse clinical behavior that largely depends on the tumor biology. Neuroblastoma exhibits unique features, such as early age of onset, high frequency of metastatic disease at diagnosis in patients over 1 year of age and the tendency for spontaneous regression of tumors in infants. The high-risk tumors frequently have amplification of the MYCN oncogene as well as segmental chromosome alterations with poor survival. Recent advanced genomic sequencing technology has revealed that mutation of ALK, which is present in ~10% of primary tumors, often causes familial neuroblastoma with germline mutation. However, the frequency of gene mutations is relatively small and other aberrations, such as epigenetic abnormalities, have also been proposed. The risk-stratified therapy was introduced by the Japan Neuroblastoma Study Group (JNBSG), which is now moving to the Neuroblastoma Committee of Japan Children's Cancer Group (JCCG). Several clinical studies have facilitated the reduction of therapy for children with low-risk neuroblastoma disease and the significant improvement of cure rates for patients with intermediate-risk as well as high-risk disease. Therapy for patients with high-risk disease includes intensive induction chemotherapy and myeloablative chemotherapy, followed by the treatment of minimal residual disease using differentiation therapy and immunotherapy. The JCCG aims for better cures and long-term quality of life for children with cancer by facilitating new approaches targeting novel driver proteins, genetic pathways and the tumor microenvironment.

Reflections on screening mammography and the early detection of breast cancer: A Countercurrents Series

A little learning is a dangerous thing.[...]

Cooperative group trials in pediatric oncology: the surgeon's role

The early history of the pediatric cooperative group trials is reviewed, and the surgeons who played a critical role in their formation are discussed. The vital information provided from the tumor specimens submitted as part of the protocols is presented, as well as how this information advanced our management of infants and children treated on current protocols of the Children's Oncology Group. Finally, a survey of the surgeons currently active in the clinical trials defined the "critical lessons" learned from the sequence of protocols by the cooperative groups which have advanced our surgical treatment of patients today.

A prospective study of a long-term follow-up of an observation program for neuroblastoma detected by mass screening

BACKGROUND

A nationwide mass screening for neuroblastoma (NBL) in 6-month-old infants (MS6M) was performed in Japan from 1985 to 2003. Favorable biological features were identified for most of the detected tumors; consequently, we began an observation program for selected screened patients in 1993. Here, we report the clinicopathological findings and present status of patients enrolled in our observation program, with the goal of evaluating its usefulness.

PROCEDURE

Between 1993 and 2003, 53 of 101 patients with NBL detected by MS6M were enrolled. The patients were divided into four groups according to changes in urinary VMA and HVA levels and tumor size.

RESULTS

Urinary VMA and HVA levels decreased in 39 of 53 patients. In 17 of these 39 patients, the tumor became undetectable (Group A); in 22 patients the tumor was detectable (Group B). In seven patients, tumor marker levels varied, and tumor volume gradually increased (Group C). In six patients, tumor marker levels and tumor volume increased in the short term (Group D). One patient had multiple tumors (1M according to International Neuroblastoma Staging System). All tumors in Groups C and D, four tumors in Group B, and one tumor in the 1M patient were removed. No unfavorable biologic factors were noted in any excised tumor.

CONCLUSIONS

The observation program of the present study, one of the largest series for MS6M, confirmed that over 70% of patients who fulfilled the criteria could be observed without surgery.

Risks and benefits of ending of mass screening for neuroblastoma at 6 months of age in Japan

PURPOSE

The mass screening (MS) for neuroblastoma (NB) at 6 months of age in Japan was discontinued in 2004. This study assessed the risks and benefits of MS based on an analysis of NB detected before or after discontinuation of MS in Japan.

METHODS

The clinical features and Brodeur's genetic type based on MYCN, DNA ploidy, and other genetic aberrations were assessed in 113 NB patients (20 cases after and 93 cases [55 MS cases] before the discontinuation of MS) older than 6 months treated at one institution since 1985.

RESULTS

The 20 patients with NBs detected after MS was discontinued ranged in age from 7 to 67 months, 12 patients were stage 4, and 11 patients would have been detected at 6 months of age if they had undergone MS. The Brodeur's genetic type of these 20 patients showed that 30% (6/20) were type 1 (low risk), 55% (11/20) were type 2A (intermediate risk), and 15% (3/20) were type 2B (high risk). Of 93 patients with NB detected before MS was discontinued, 60% (56/93) were type 1, 18% (17/93) were type 2A, and 22% (20/93) were type 2B. Among the type 2A patients, 82% (9/11) of the patients detected after MS was discontinued showed stage 4, whereas only 50% (9/18) of those diagnosed before MS was discontinued were stage 4. The genetic analysis using single nucleotide polymorphism (SNP) array for type 2A showed that the pattern of genetic aberration was equivalent in those detected either before or after MS was discontinued.

CONCLUSIONS

There was a decrease of type 1 and an increase of type 2A NB in patients after MS was discontinued in Japan. These results suggest that most of the type 1 detected by MS has regressed, and most of the type 2A detected by MS has appeared sporadically as advanced NB in patients older than 1 year.

Perinatal risk factors for neuroblastoma

Neuroblastoma is the most common cancer among infants, suggesting an etiologic role for prenatal factors. In this case-cohort study, neuroblastoma cases (n = 529) diagnosed between 1985 and 2001 were identified from the New York State Cancer Registry and were matched to the electronic birth records for 1983-2001 from New York State and New York City. Controls (n = 12,010) were selected from the same birth cohorts. Analysis was stratified by age at diagnosis, with one to six months (younger infants), seven to 18 months (older infants), and older than 18 months (older children) analyzed separately. Perinatal exposure data was obtained from the birth certificates. No risk factors were identified to be consistently associated with risk across all three age groups. Generally, more risk factors were identified as associated with neuroblastoma among younger infants relative to older ages, including high birth weight, heavier maternal gestational weight gain, maternal hypertension, older maternal age, ultrasound, and respiratory distress. Among older infants, low birth weight was associated with increased risk while heavier maternal gestational weight gain was protective. In the oldest age group, first born status, primary cesarean delivery, prolonged labor and premature rupture of the membranes were associated with increased risk.

Neuroblastoma

The clinical hallmark of neuroblastoma is heterogeneity, with the likelihood of cure varying widely according to age at diagnosis, extent of disease, and tumour biology. A subset of tumours will undergo spontaneous regression while others show relentless progression. Around half of all cases are currently classified as high-risk for disease relapse, with overall survival rates less than 40% despite intensive multimodal therapy. This Seminar focuses on recent advances in our understanding of the biology of this complex paediatric solid tumour. We outline plans for the development of a uniform International Neuroblastoma Risk Group (INRG) classification system, and summarise strategies for risk-based therapies. We also update readers on new discoveries related to the underlying molecular pathogenesis of this tumour, with special emphasis on advances that are translatable to the clinic. Finally, we discuss new approaches to treatment, including recently discovered molecular targets that might provide more effective treatment strategies with the potential for less toxicity.

Perinatal neuroblastoma

One-fifth of all neuroblastomas are diagnosed either antenatally or in the first 3 months of life. Over the past two decades, routine prenatal ultrasound has significantly increased the rate of diagnosis of fetal neuroblastoma. More than 90% of these tumors arise in the adrenal gland, suggesting a link between perinatal tumors and the nodular collections of neuroblasts that are part of normal adrenal development. In fact, there is compelling evidence that the cystic variant of perinatal neuroblastoma is caused by a perturbation of the involution program of these neuroblastic nodules. The vast majority of these cases are localized tumors with favorable biological features, which correlates with a 4-year survival of greater than 95%. The high rate of spontaneous regression of these tumors, coupled with the significant risks of resectional surgery in small neonates, has prompted the development of a prospective clinical trail of expectant observation as primary therapy for infants with small, localized tumors. The ultimate goal of such studies is to define an ultra-low-risk group of neuroblastoma patients who do not require invasive procedures or chemotherapy to achieve an excellent outcome.

Profile of neuroblastoma detected by mass screening, resected after observation without treatment: results of the Wait and See pilot study

BACKGROUND/PURPOSE

Neuroblastoma (NB) detected by mass screening (MS) usually shows favorable prognosis and sometimes regresses spontaneously. Therefore, the authors started an observation program for these patients to avoid overtreatment. In this study, the authors analyzed the profile of NB resected after observation to elucidate the nature of NB detected by MS.

METHODS

Between 1994 and 2004, 22 NB patients matched the following criteria and entered the observation program after obtaining informed consent: stage I or II, less than 5 cm in diameter, and without involvement of large vessels or organs. If increase in size, elevation of tumor markers, or evidence of metastasis was observed, the tumor was immediately resected.

RESULTS

Thirteen (59%) of 22 cases showed spontaneous regression. In the remaining 9 cases, tumors were resected because of parents' request, increase in size, and/or elevation of tumor markers. Four tumors had at least one unfavorable biologic feature, and 3 of them had more than 2. According to Shimada's system, 2 had unfavorable histology. One was diploid tumor, 3 had 1p deletion, and Trk-A expression was low in 4 tumors. All patients survived without evidence of recurrence.

CONCLUSIONS

The observation program has shown that at least one third of the NB detected by MS regressed spontaneously. On the other hand, MS may detect some cases with unfavorable tumor in early stage, which benefit from screening.

Radically different treatment recommendations for newly diagnosed neuroblastoma: pitfalls in assessment of risk

Neuroblastoma risk stratification is based on stage, age, and biology and prescribes surgery for low-risk disease, moderate-dose chemotherapy for intermediate-risk disease, and maximal therapy (including myeloablative treatment with stem cell transplantation) for high-risk disease. Four cases are described that depict pitfalls in risk assessment with potentially far-reaching consequences. This report focuses on a subset of four patients referred for second opinions. Stage was defined by the International Neuroblastoma Staging System. The first recommendations were for maximal therapy, but second opinions were radically different (ie, surgery alone). Ages at diagnosis were 15 to 25 months. Shimada histopathology was unfavorable in three of the four patients, but chromosomal, serum, and urine prognostic markers were favorable. All four patients did well without cytotoxic therapy (follow-up: 2 years 10 months plus to 4 years 8 months plus). Patient 1 had abdominal and upper thoracic/supraclavicular masses (stage 4); the former was resected and the latter spontaneously regressed. Patient 2 had retroperitoneal disease, without bone marrow involvement, but imaging studies showed lesions in vertebral bodies. Biopsies of the latter showed no neuroblastoma and the primary tumor (with regional lymph nodes) was resected, changing stage from 4 to 2B. Patient 3 had a retroperitoneal mass but no distant disease. Though initially deemed to be unresectable, the abdominal tumor was excised, changing the classification from high risk (stage 3 with unfavorable histopathology) to low risk (stage 1). Patient 4 had a pelvic mass, with unfavorable histopathology, and bilateral inguinal lymph node involvement (stage 3); all soft tissue disease was resected. The absence of cortical bone and extensive bone marrow metastatic involvement in a young neuroblastoma patient should cause a shift in attention to biologic prognostic markers. Some patients classified as having high-risk neuroblastoma might actually do well with no cytotoxic therapy.

Stephen L. Gans overseas lecture. Mass screening for neuroblastoma in Japan: lessons learned and future directions

BACKGROUND/PURPOSE

Since 1985, a nationwide mass screening program (MS) for neuroblastoma has been conducted for 6-month-old infants throughout Japan, resulting in the detection of more than 1,900 cases of neuroblastoma. The outcome of these patients has been excellent: more than 97% of them are alive. Yet, several reports suggest that the number of advanced-stage neuroblastoma patients over 1 year of age has not changed substantially. The current report focuses on the 15-year experience with MS of the Kyushu Pediatric Oncology Study Group.

METHODS

The clinical and biological features of neuroblastoms detected (n = 320) and not detected by MS (n = 245) were compared. Regional and national statistics for neuroblastoma before and after 1985 were analyzed using standard epidemiologic measures for the occurrence of disease.

RESULTS

The majority of the MS-positive cases were biologically favorable and had an excellent outcome. In contrast, the majority of non-MS patients in whom neuroblastoma later developed had advanced-stage, unfavorable-prognosis tumors. The overall mortality rate of neuroblastoma in the Kyushu area was not improved by MS.

CONCLUSIONS

The optimal time for screening is the point at which neuroblastomas regressing spontaneously can no longer be detected, but more aggressive disease can be found. A birth cohort study could determine the optimal timing for a second screening. Identification of other new prognostic factors may be required.

Marginal decrease in mortality and marked increase in incidence as a result of neuroblastoma screening at 6 months of age: cohort study in seven prefectures in Japan

PURPOSE

To determine the usefulness of 6-month screening for neuroblastoma.

PATIENTS AND METHODS

The cumulative incidence rates (IRs) and cumulative mortality rates (MRs) of neuroblastoma in children younger than 60 months of age were analyzed for control (n = 713,025), qualitative screening (Qual Screen, n = 1,142,519), and quantitative screening (Quan Screen, n = 550,331) cohorts, and for Screened and Unscreened subgroups within screening cohorts.

RESULTS

IRs (per 100,000) for infants aged 6 to 11 months were 1.12 in Control, 5.69 in Qual Screen (P <.0001), and 17.81 in Quan Screen (P <.0001); IRs for children aged 12 to 59 months were 7.29 in Control, 5.86 in Qual Screen (P =.28), and 6.36 in Quan Screen (P =.60). IRs for children aged 12 to 59 months in Unscreened or Screened subgroups remained at the same level. When patients diagnosed at younger than 6 months of age were excluded, the MR (per 100,000) under 60 months for Control was 4.21; those in Unscreened and Screened subgroups were 3.84 and 2.53 in Qual Screen (P =.30), and 3.20 and 1.97 in Quan Screen (P =.73), respectively; MRs between Control and Unscreened subgroups revealed no significant differences (P =.89 in Qual Screen, P =.85 in Quan Screen).

CONCLUSION

Six-month screening resulted in a marked increase in incidence for infants with no significant decrease in incidence for children older than 1 year of age. A decrease in mortality was observed, but it was not significant. The usefulness of screening is questionable, because the decrease of mortality should be balanced against the adverse effect of overdiagnosis and the psychological burden on parents and children.

Clinical and biologic characteristics for recurring neuroblastoma at mass screening cases in Japan

BACKGROUND

It is said that most cases detected by neuroblastoma mass screening at 6 months of age tend to have a favorable clinical course after a surgical resection either with or without mild chemotherapy. However, a few cases have an unfavorable outcome. In the current study, the authors analyzed the clinical and biologic characteristics for recurring neuroblastoma in mass screening cases.

METHODS

In 245 cases detected through mass screening in the Kyushu area in Japan, the clinical data and biologic features (N-myc status, DNA ploidy, Shimada histology, neuron-specific enolase (NSE), ferritin) were investigated, whereas, in particular, the data for recurring cases also were analyzed.

RESULTS

Of 245 cases, 28 tumors had one or more biologically unfavorable prognostic factors, and 6 patients experienced recurrence. Three of the six patients with recurring disease underwent a complete resection of the primary tumor, whereas three cases had undergone an incomplete resection of the tumor. Regarding the initial chemotherapy, three cases received mild chemotherapy, two cases received no chemotherapy, and one case had high-dose multidrug chemotherapy. Regarding biologic prognostic factors, four of six cases with recurring disease had one or more unfavorable factors, whereas two cases had no unfavorable factors. Regarding the outcome after recurrence, four cases are CR, one case has a stable residual tumor, and one case died of disease with N-myc amplification.

CONCLUSIONS

Most neuroblastomas detected by mass screening at 6 months of age have biologically favorable factors. However, approximately 10% of the cases had one or more unfavorable factors and thus might have a higher risk of recurrence than the patients with no unfavorable factors. Conversely, some cases with recurring disease had no unfavorable factors; however, the reason for this is still unclear. A long-term follow-up for mass screening cases is important, and it also might be necessary to research the established biologic factors and identify other new prognostic factors.

Mass screening for neuroblastoma at 6 months of age: difficult to justify

BACKGROUND/PURPOSE

A statistical analysis of the mass screening for neuroblastoma in Japan based on a population study rarely has been reported. This study aims to evaluate retrospectively the effectiveness of mass screening at 6 months of age using the available population data.

METHODS

The data on the neuroblastoma cases registered by the Committee for Pediatric Solid Malignant Tumors in the Kyushu area were analyzed based on both screened and unscreened populations in the Kyushu area.

RESULTS

From 1988 to 1992, the cumulative incidence of neuroblastoma in children less than 5 years of age was 82 in 484,599 for screened children, and 11 in 92,966 for unscreened children, respectively. Fourteen of the 82 screened patients had negative findings at 6 months of age (MS-negative cases). No significant difference was observed in the cumulative mortality rates from neuroblastoma in children younger than 5 years of age between the screened children and the unscreened children. Six of seven patients who died among the screened children were MS-negative cases with stage III or IV disease. In addition, no significant difference was found in the cumulative mortality rates from the neuroblastoma cases in patients less than 5 years of age between the children screened from 1988 to 1992 (7 of 484,599) and all children from 1980 to 1984 (14 of 668,084).

CONCLUSIONS

These findings suggests that the majority of the patients detected by mass screening had a favorable prognosis, and, mass screening in Japan for children less than 6 months of age was not observed to reduce the incidence and mortality from neuroblastoma. Therefore, mass screening at 6 months of age was not found to improve substantially the prognosis of patients with unfavorable neuroblastoma identified over 1 year of age, which is the primary purpose of such mass screening for neuroblastoma.

Familial neuroblastoma: report of a kindred with later age at diagnosis

PURPOSE

To describe the clinical and biologic features of neuroblastoma (NB) in two siblings and their maternal second cousin.

PATIENTS AND METHODS

NB was diagnosed in the siblings at 2 1/2 (patient 2) and 5 (patient 3) years of age. NB was diagnosed in their maternal second cousin (patient 1) when she was 7 years old. Standard clinical and biological data, tumor karyotype, and tumor allelotype at select loci were obtained.

RESULTS

Patient 1 had International Neuroblastoma Staging System (INSS) stage 4 NB and unfavorable histology but no evidence of MYCN amplification; she died from complications of autologous bone marrow transplantation in second remission. Patient 2 had INSS stage 4 NB with unfavorable histology but no MYCN amplification; her disease recurred 39 months after completing therapy. Patient 3 had INSS stage 1 NB with favorable biologic features; he was treated with surgical excision and remains free of disease.

CONCLUSIONS

Familial NB may occur at a later age than predicted by the tumor suppressor gene model of inherited cancer. This report further emphasizes the clinical and biological heterogeneity of familial NB.

10 years' neuroblastoma screening in Europe: preliminary results of a clinical and biological review from the Study Group for Evaluation of Neuroblastoma Screening in Europe (SENSE)

Between January 1986 and May 1996, 870,313 children were tested in European neuroblastoma (NB) screening programmes. Among these children, 82 cases of NB (age range 4-24 months, median 11 months) were detected by screening. 83% of the patients had localised NB and 17% were diagnosed with generalised NB (stage 4, 10%; stage 4s, 7%). Unfavourable biological markers (MYCN amplification, loss of heterozygosity (LOH) 1p36, DNA di/tetraploidy) were observed in 14% of 76 biologically examined cases. The median follow-up time of all the patients was 21.5 months (range 1-101 months). To date, 69 patients are in complete remission (CR) and 2 patients have died due to therapy (stage 4, 1 patient; stage 3, 1 patient with unfavourable markers). Apart from screened patients, 16 other patients with NB were found who had previously had a normal screening test, i.e. 'false negative' patients (age range 10-41 months, median 31.5 months). The median interval between screening and diagnosis was 24.5 months (range 6-35 months). 11 of the 'false negative' patients suffered from generalised NB (stage 4) and 5 had localised NB at diagnosis. Unfavourable biological markers were observed in 7/12 patients. 5 patients have died, 2 achieved partial remission and 9 CR. 9 of the 11 patients with unfavourable biological markers diagnosed due to NB screening are currently in CR. It is very likely that, among the patients without unfavourable biological markers, we detected tumours which may have regressed spontaneously. These children may have undergone 'unnecessary,' but unavoidable, diagnostic procedures and therapy. To reduce the number of 'false negative' patients, a later screening could be helpful and should be evaluated.

Pathology review of screening negative neuroblastomas: a report from the Quebec Neuroblastoma Screening Project

BACKGROUND

The Quebec Neuroblastoma Screening (QNS) Project completed a 5-year program for measuring urinary vanillylmandelic acid (VMA)/homovanillic acid (HVA) levels at age 3 weeks and/or 6 months in 89% of 476,603 Quebec-born infants from 1989-1994; 45 screening positive preclinical cases (S-positive cases) and 20 congenital/neonatal (C/N) cases were identified. As of April 1997, an additional 59 cases in the same birth cohort were diagnosed clinically; these neuroblastomas developed after screening verified normal VMA/HVA levels (S-negative cases).

METHODS

Pathology specimens from 45 of 59 S-negative cases were reviewed centrally and classified according to the Shimada system. Results were compared with clinical data and also with S-positive and C/N cases.

RESULTS

Of 45 S-negative cases, 27 tumors had favorable histology (FH) and 18 had unfavorable histology (UH). Approximately 52% of FH tumors were diagnosed before age 1 year, whereas UH tumors were nearly exclusively (94%) diagnosed after age 1 year (P < 0.01). Approximately 89% of FH tumors were Stage I, II, or IV-S, whereas 72% UH tumors were Stage III or IV (P < 0.001). All children with FH tumors were alive at last follow-up (range of follow-up period: 9-79 months; median, 35 months), whereas 8 children with UH tumors died of disease even after limited follow-up (range of follow-up period: 0-60 months; median, 20 months). By contrast, S-positive and C/N cases were predominantly (97%) FH tumors, often (76%) Stage I, II, or IV-S, with excellent clinical outcome (survival rate of 98%).

CONCLUSIONS

The majority of the UH neuroblastomas that developed in the birth cohort of the QNS Project were included in the group of S-negative cases and could not be detected by the screening at age 3 weeks and/or 6 months.