Local treatment in initially unresected non-rhabdomyosarcoma soft-tissue sarcomas of children and adolescents: A retrospective single-center experience.

BACKGROUND: Pediatric non-rhabdomyosarcoma soft-tissue sarcomas (NRSTS) are a heterogeneous group of aggressive tumors. Patients with locally advanced/initially unresected disease represent a subset of patients with unsatisfactory outcome: limited data are available on the best treatment approach, in particular regarding local therapy. METHODS: This retrospective analysis concerned 71 patients < 21 years old with nonmetastatic, initially unresected adult-type NRSTS, treated at a referral center for pediatric sarcomas from 1990 to 2021. Patients were treated using a multimodal approach, based on the protocols adopted at the time of their diagnosis. RESULTS: The series included a selected group of patients with unfavorable clinical characteristics, i.e., most cases had high-grade and large tumors, arising from axial sites in 61% of cases. All patients received neoadjuvant chemotherapy, 58 (82%) had delayed surgery (R0 in 45 cases), and 50 (70%) had radiotherapy. Partial response to chemotherapy was observed in 46% of cases. With a median follow-up of 152 months (range, 18-233), 5-year event-free survival (EFS) and overall survival (OS) were 39.9% and 56.5%, respectively. Survival was significantly better for patients who responded to chemotherapy, and those who had a delayed R0 resection. Local relapse at 5 years was 7.7% for patients who did not undergo delayed surgery. CONCLUSIONS: Our series underscores the unsatisfactory outcome of initially unresected NRSTS patients. Improving the outcome of this patient category requires therapeutic strategies able to combine novel effective systemic therapies with a better-defined local treatment approach to offer patients the best chances to have R0 surgery.

Caring for children with cancer evacuated from Ukraine: The patients' perception.

BACKGROUND AND AIMS: Since the beginning of the war in Ukraine on February 24, 2022, many pediatric oncology centers welcomed evacuated patients. To better understanding the needs of patients and families arriving at two Lombardy hospitals in the period March to November 2022, an anonymous questionnaire investigated the families' backgrounds, feelings, and impressions about hospitality and care. METHODS: Twenty questions investigated how patients had reached Italy, from whom they had received help (logistically/financially); the emotions regarding their status as war refugees; the knowledge, expectations, and opinions about Italy and Italians; the quality of medical care received and the relationships with the healthcare staff; lastly, suggestions to improve assistance. RESULTS: The questionnaires were completed by 19/32 patients/parents in November 2022 in two different pediatric-oncology centers. Most families had reached Italy (58%) and received medical care (95%) with the help of charities and the Italian Public Health Care System. A significant majority (69%) expressed satisfaction with the assistance provided. The Italian population demonstrated remarkable warmth, for 95% exhibiting friendliness and for 58% generosity. An improvement in their stay could be linked with the positive outcome of their children's cancer (15%), achieving complete family reunification (15%), the cessation of the conflict (10%), and the overcoming of language barriers (10%). CONCLUSIONS: Providing care for children from another country, not only grappling with the trauma of fleeing their homeland but also battling cancer, is an immense undertaking. It demands a diverse range of efforts and resources to ensure a positive and fulfilling outcome for this experience.

Relapse after nonmetastatic rhabdomyosarcoma: Salvage rates and prognostic variables.

BACKGROUND: Patients with relapsing rhabdomyosarcoma (RMS) pose a therapeutic challenge, and the survival rate is reportedly poor. We describe a retrospective series of relapsing RMS patients treated at a referral center for pediatric sarcoma, investigating the pattern of relapse, salvage rates, and factors correlating with final outcomes. METHODS: The analysis concerned 105 patients <21 years old treated from 1985 to 2020 with initially localized RMS at first relapse. For risk-adapted stratification purposes, patient outcomes were examined using univariable and multivariable analyses based on patients' clinical features at first diagnosis, first-line treatments, clinical findings at first relapse, and second-line treatments. RESULTS: First relapses occurred 0.08-4.8 years (median 1 year) following initial diagnosis and were local/locoregional in 59% of cases. Treatment at first relapse included chemotherapy in all but two cases, radiotherapy in 38, and surgery in 21. Median event-free survival (EFS) after first relapse was 4 months, while 5-year EFS was 16.3%; median overall survival (OS) was 9 months, while 5-year OS was 16.7%. Several variables influenced survival rates. Considering only clinical findings and treatment at relapse, Cox's multivariable analysis showed that OS correlated significantly with time to relapse, radiotherapy administered at relapse, response to chemotherapy, and whether a second remission was achieved. CONCLUSION: Survival following first relapse of patients with localized RMS at initial diagnosis is poor. The variables found to influence survival can be utilized in a risk-adapted model to estimate the chances of salvage to guide decisions for second-line treatments.

Relapse after non-metastatic rhabdomyosarcoma: The impact of routine surveillance imaging on early detection and post-relapse survival.

BACKGROUND: Patients with rhabdomyosarcoma (RMS) whose disease relapses have little chance of being cured, so front-line treatments are usually followed up with surveillance imaging in an effort to detect any recurrences as early as possible, and thereby improve post-relapse outcomes. The real benefit of such routine surveillance imaging in RMS remains to be demonstrated, however. This retrospective, single-center study examines how well surveillance imaging identifies recurrent tumors and its impact on post-relapse survival. METHODS: The analysis concerned 79 patients <21 years old treated between 1985 and 2020 whose initially localized RMS relapsed. Clinical findings, treatment modalities, and survival were analyzed, comparing patients whose relapse was first suspected from symptoms they developed (clinical symptoms group) with those whose relapse was identified by radiological surveillance (routine imaging group). RESULTS: Tumor relapses came to light because of clinical symptoms in 42 cases, and on routine imaging in 37. The time to relapse was much the same in the two groups. The median overall survival (OS) and 5-year OS rate were, respectively, 10 months and 12.6% in the clinical symptoms group, and 11 months and 27.5% in the routine imaging group (p-value .327). Among patients with favorable prognostic scores, survival was better for those in the routine imaging group (5-year OS 75.0% vs. 33.0%, p-value .047). CONCLUSION: It remains doubtful whether surveillance imaging has any real impact on RMS relapse detection and patients' post-relapse survival. Further studies are needed to establish the most appropriate follow-up recommendations, taking the potentially negative effects of regular radiological exams into account.

Secondary osteosarcoma: a challenge indeed.

BACKGROUND: The risk of survivors developing a secondary bone sarcoma after being treated for pediatric cancers is well established. The aim of this study was to examine the clinical characteristics and outcomes of patients with secondary osteosarcoma (SOS). METHODS: The study concerns survivors of childhood and adolescence primary neoplasms (PN) treated with chemotherapy, with or without radiotherapy and surgery, subsequently diagnosed with SOS. RESULTS: We identified 26 patients (13 females, 13 males) who developed SOS a median 7.3 years after being diagnosed with a PN (5/7 of these patients tested for Li-Fraumeni and found positive for the syndrome). The sample's median age was 8.0 and 15.0 years when their PN and SOS were diagnosed, respectively. To treat their PN, 24 out of 26 patients had been given radiotherapy, and 19 had received chemotherapy including doxorubicin. A considerable number of SOS occurred at unfavorable sites (nine hip bone, six skull). All but one patient received chemotherapy with tailored schedules, omitting doxorubicin in 19 cases. Eighteen of the 26 patients underwent surgery. The 5- and 10-year overall survival and probabilities after the diagnosis of SOS (95% confidence interval) were 50% (32.7-76.5%) and 38.9% (22.4-67.4%); 5- and 10-year progression-free survival was 47% (29.9-73.7%) and 35.2% (19.3-64.4%), respectively. CONCLUSIONS: The survival rates after SOS are lower than in patients with primary osteosarcoma, but not negligible. It is therefore mandatory to discuss the best choice of treatment for such patients at a referral center, in terms of their chances of cure and quality of life.

Langerhans cell histiocytosis in adults: a retrospective, single-center case series.

Langerhans cell histiocytosis is rare in adults, and most of what we know about its diagnosis and treatment comes from pediatric studies. We report clinical findings and results of treatment in a retrospective series of 63 consecutive adult patients (18-76 years old), treated at our pediatric unit from 1990 to 2020 using the same approach as for children. Patients were classified as having single-system disease (SS-LCH) in 41 cases, which was unifocal in 34 of them and multifocal in 7, or multisystem disease (MS-LCH) in 17 and primary pulmonary (pLCH) in 5. Twenty patients also had diabetes insipidus. A "wait and see" strategy was recommended after biopsy/surgery for patients with unifocal SS-LCH. Systemic treatment was proposed for cases of SS-LCH involving "special sites" or with multifocal disease, and in cases of MS-LCH. EFS and OS for the cohort as a whole were 62.2% and 100%, respectively, at 5 years and 52.5% and 97.6% at 10 years. Three patients died due to the damage caused by the multiple therapies administered. The rate of disease reactivation was high (affecting 40% of cases), with several reactivations over the years despite multiple lines of treatment. Though clinical history of LCH may differ between adults and children, in the absence of specific, tailored protocols, clinical approach to adult cases may draw on pediatric experience. Patients with limited disease have a good prognosis without any need for systemic therapy. Potentially greater toxicity in adults of systemic treatments generally used in pediatric setting should be borne in mind.

How ten-years of reirradiation for paediatric high-grade glioma may shed light on first line treatment.

PURPOSE: Recurrence incidence for paediatric/adolescent high-grade glioma (HGG) exceeds 80%. Reirradiation (reRT) palliates symptoms and delays further progression. Strategies for reRT are scarce: we retrospectively analysed our series to develop rational future approaches. METHODS: We re-evaluated MRI + RT plans of 21 relapsed HGG-patients, accrued 2010-2021, aged under 18 years. All underwent surgery and RT + chemotherapy at diagnosis. Pathologic/molecular re-evaluation allowed classification based on WHO 2021 criteria in 20/21 patients. Survival analyses and association with clinical parameters were performed. RESULTS: Relapse after 1st RT was local in 12 (7 marginal), 4 disseminated, 5 local + disseminated. Re-RT obtained 8 SD, 1 PR, 1PsPD, 1 mixed response, 10 PD; neurological signs/symptoms improved in 8. Local reRT was given to 12, followed again by 6 local (2 marginal) and 4 local + disseminated second relapses in 10/12 re-evaluated. The 4 with dissemination had 1 whole brain, 2 craniospinal irradiation (CSI), 1 spine reRT and further relapsed with dissemination and local + dissemination in 3/four assessed. Five local + disseminated tumours had 3 CSI, 1 spine reRT, further progressing locally (2), disseminated (1), n.a. (1). Three had a third RT; three were alive at 19.4, 29, 50.3 months after diagnosis. Median times to progression/survival after re-RT were 3.7 months (0.6-16.2 months)/6.9 months (0.6-17.9 months), improved for longer interval between 1st RT and re-RT (P = 0.017) and for non-PD after reRT (P < 0.001). First marginal relapse showed potential association with dissemination after re-RT (P = 0.081). CONCLUSIONS: This is the biggest series of re-RT in paediatric HGG. Considering the dissemination observed at relapse, our results could prompt the investigation of different first RT fields in a randomized trial.

Extraosseous Ewing sarcoma in children and adolescents: A retrospective series from a referral pediatric oncology center.

BACKGROUND: Extraosseous Ewing sarcoma is a rare entity and less is known about its clinical behavior and optimal treatment than for its counterpart in bone. This study is a retrospective analysis on a cohort of patients <21 years treated according to a "soft tissue sarcoma approach." METHODS: The "extraosseous" origin of the tumor was established on radiological findings, based on the lack of any bone involvement. Patients were treated using a multimodality approach including surgery, radiotherapy, and chemotherapy. All patients received chemotherapy with alkylating agents and anthracyclines for 25 weeks (nine courses). Radiotherapy (45-54.8 Gy) was required for all cases except those who had an initial R0 resection of tumors smaller than 5 cm. RESULTS: Fifty-seven patients (age 2-20 years, median 14) were treated from 1990 to 2020. Ten-year event-free survival (EFS) and overall survival (OS) were 77.5% and 85.5% in patients with localized disease, and 11.1% and 29.6% in those with metastatic disease (p < .001) (follow-up 5-349 months, median 107 months). In patients with localized disease, the most recent IVADo-IVE regimen achieved excellent survivals, that is, 10-year EFS 95.5%. CONCLUSIONS: Our study showed that satisfactory results were achieved in patients with localized extraosseous Ewing sarcoma treated with a tailored approach derived from soft tissue sarcoma protocols, which was less intensive and shorter as compared to the standards utilized for the management of bone Ewing sarcoma. Our study suggests that the extraskeletal site might be considered as a variable to stratify patients and modulate treatment intensity accordingly in Ewing sarcoma protocol.

Bilateral adrenal primary tumor in Stage 4S neuroblastoma: The Italian experience and review of the literature.

Bilateral adrenal neuroblastoma (NB) is rare and is mainly stage 4S. Its incidence, presenting features, management, and outcome have not been fully defined yet. We searched the Italian NB Registry (RINB) for stage 4S NB infants with bilateral adrenal primary tumor to compare them with stage 4S NB with unilateral tumor. Between 1979 and 2016, the RINB enrolled 3731 NB patients aged 0-18 years including 317 infants (8.5%) diagnosed with stage 4S NB. Eleven/317 (3.5%) had a bilateral adrenal primary tumor (Group 1) and 190/317 (59.9%) had a unilateral tumor (Group 2). Group 1 infants were significantly younger (51 vs. 89 days) but were comparable with Group 2 for any other presenting features. In the absence of specific protocols, upfront treatment was based on symptoms, size of adrenal tumors, and biology, and consisted of observation in 5 cases, radiotherapy in one, chemotherapy in 2, and surgery in 3. Five/11 developed progression and 2 of them, both with MYCN amplification, died. The 5-year EFS rates of Group 1 and 2 were 54.5% vs. 73.3% (P=.14) and 5-year OSs were 81.8% and 89.4%, respectively (P=.44). Our data support the hypothesis that 4S NB infants with bilateral adrenal tumors can have favorable outcome with personalized therapeutic approach. The three patients with MYCN amplified tumor benefited from upfront aggressive chemotherapy, in accordance with current protocols. Because of the rarity of this intriguing form of neuroblastoma, collaborative prospective studies are warranted, especially in view of gaining a better insight on its biological and genetic features.

Age-appropriate multidisciplinary approach to young children with cancer undergoing radiotherapy: The SIESTA procedure.

A standardized multidisciplinary step-by-step approach to improve the compliance of young (or difficult) children having to undergo radiotherapy was described and applied. The procedure is called SIESTA, which stands for show-imagination-evaluation-support-treatment-anesthesia. Preliminary assessments suggest that the SIESTA approach was effective: the rate of young patients (≤6 years) requiring anesthesia decreased from 27% (14/52 cases) in 2011-2012 (before the procedure was adopted) to 13% (6/46) in 2018.

Correlation between oncological family history and clinical outcome in a large monocentric cohort of pediatric patients with rhabdomyosarcoma.

BACKGROUND: Rhabdomyosarcoma (RMS), an aggressive soft tissue sarcoma of the skeletal muscle generally affecting children and adolescents, shows extensive heterogeneity in histology, site and age of onset, clinical course, and prognosis. Tumorigenesis of RMS is multifactorial and genetic predisposition together with the family history of cancer may provide critical information to enhance the current knowledge and foster genetic counseling and testing. METHODS: In our study, we evaluated the possible correlation of oncological family history with clinical outcomes in a cohort of RMS 512 patients and treated at the Pediatric Oncology Unit of our Institute. Family history was retrospectively collected from the specific ad hoc form available in medical records and filled in through an interview with the patients' parents at the time of RMS diagnosis. RESULTS: While our series did not show a specific association between oncological family history and clinical variables, we observed an association with survival probabilities: among patients with a history of cancer-affected first-degree relatives at the time of the diagnosis, all children with alveolar RMS (ARMS) died of disease. CONCLUSION: Our study not only reports an interesting and not previously described association between a poor clinical outcome and ARMS in patients with young cancer-affected relatives, but also stimulates the discussion on oncological family history in RMS, to improve the clinical management of these young patients and their families.

Customised pediatric palliative care: Integrating oncological and palliative care priorities.

AIM: To describe the experience involving the early introduction of palliative care (PC) in oncological patients treated within the paediatric oncology unit of the Istituto Nazionale Tumori of Milan and compare this cohort with a cohort of patients resident in the same area treated before the introduction of early palliative care. METHODS: A virtual team was assembled in 2015. The PC providers operate outside the hospital. Conference calls were scheduled to discuss patients' problems. This sample was compared with the clinical records of patients residing in the same area who died between 2009 and 2014. RESULTS: Between January 2015 and April 2019, 41 patients residing in the Milan area mainly with CNS tumours or sarcomas were referred to the team. Comparing the results with the previous cohort, there was a rise in the number of patients dying at home or in a hospice and the duration of PC increased over time. From 2015, none of the patients died in an intensive care unit. CONCLUSION: Patients managed by the virtual team were able to continue their cancer treatments, take part in Phase I trials and receive PC. All patients with a poor prognosis should have PC at an early stage.

Reduced-dose craniospinal irradiation is feasible for standard-risk adult medulloblastoma patients.

INTRODUCTION: Medulloblastoma is the most common malignant brain tumor in children, but accounts for only 1% of brain cancers in adults. For standard-risk pediatric medulloblastoma, current therapy includes craniospinal irradiation (CSI) at reduced doses (23.4 Gy) associated with chemotherapy. Whereas most same-stage adult patients are still given CSI at 36 Gy, with or without chemotherapy, we report here on our use of reduced-dose CSI associated with chemotherapy for older patients. METHODS: We gathered non-metastatic patients over 18 years old (median age 28 years, range 18-48) with minimal or no residual disease after surgery, no negative histological subtypes, treated between 1996-2018 at the Centre Léon Bérard (Lyon) and the INT (Milano). A series of 54 children with similar tumors treated in Milano was used for comparison. RESULTS: Forty-four adults were considered (median follow-up 101 months): 36 had 23.4 Gy of CSI, and 8 had 30.6 Gy, plus a boost to the posterior fossa/tumor bed; 43 had chemotherapy as all 54 children, who had a median 83-month follow-up. The PFS and OS were 82.2 ± 6.1% and 89 ± 5.2% at 5 years, and 78.5 ± 6.9% and 75.2 ± 7.8% at ten, not significantly different from those of the children. CSI doses higher than 23.4 Gy did not influence PFS. Female adult patients tended to have a better outcome than males. CONCLUSION: The results obtained in our combined series are comparable with, or even better than those obtained after high CSI doses, underscoring the need to reconsider this treatment in adults.

How young patients with cancer perceive the COVID-19 (coronavirus) epidemic in Milan, Italy: Is there room for other fears?

The rapid spread of coronavirus disease 2019 epidemic in Italy, in particular in the Milan focal point, required drastic measures and led to panic in the population. While in our center we did not change our approach to the treatment of our young patients with cancer, we developed a qualitative survey to assess their perception of the risk and level of stress. The survey showed that a relatively large proportion of young patients felt personally at risk of severe complications. We believe that we need to adequately inform our patients, focusing on hygienic measures and personal protection and prompt reporting of any suspicious symptoms.

Cancer treatment in disabled children.

The incidence of cancer in children with intellectual disability has been poorly documented. We report our experience of treating children and adolescents with cancer and intellectual disability (40 patients), from 2004 to 2018. A treatment-sparing approach was adopted for 6 patients with severe intellectual impairment to minimize toxicity: a child with postpartum asphyxia and medulloblastoma did not receive radiotherapy; 1 patient with mitochondrial encephalopathy and a testicular germ cell tumor did not receive bleomycin and lung metastasectomy; 2 patients (1 with Down + West syndrome + Wilms tumor (WT) and 1 with Denys-Drash syndrome + WT) did not receive vincristine; 1 child with corpus callosum agenesis and anaplastic ependymoma did not receive chemotherapy; 1 child with structural chromosomal aberrations and a primitive neuro-ectodermal tumor received personalized chemotherapy. Heminephrectomy was performed in 4 patients with WT to preserve their kidney function. We found no statistically significant correlation between relapse or mortality rates and the use of a treatment-sparing approach. The 5-year overall survival (OS) and event-free survival (EFS) rates were 84.5% and 66.1% as opposed to 82.5% and 46.9%, respectively, for patients in our usual-treatment and treatment-sparing groups.Conclusion: We only opted for a treatment-sparing approach for patients with severe disabilities, and their OS was in line with that of children without intellectual disability. What is Known: • There are few reports on children/adolescents with cancer and intellectual disability (ID). • It is not clear how to manage them and whether a treatment sparing should be considered, especially in the case of severe disability. What is New: • Most patients received the standard cancer treatment and only in the case of severe disability, a therapeutic saving approach was applied. • No statistically significant correlations between relapse/mortality rates and the use of a treatment-sparing approach were found.

Immune landscape and in vivo immunogenicity of NY-ESO-1 tumor antigen in advanced neuroblastoma patients.

BACKGROUND: Indirect evidence suggesting the immunosensitivity/immunogenicity of neuroblastoma is accumulating. The aims of this study were to investigate the immune landscape of neuroblastoma and to evaluate the in vivo immunogenicity of the NY-ESO-1 tumor antigen in advanced neuroblastoma patients. METHODS: The immune infiltrating cells of the NY-ESO-1+ tumors from three HLA*A201 patients with metastatic neuroblastoma who relapsed after conventional treatments were evaluated by immunohistochemistry. The patients were vaccinated with the HLA-A*0201-restricted peptide NY-ESO-1157-165(V). The peptide was emulsified in Montanide ISA51 and given subcutaneously in a phase I pilot study. The immunogenicity of NY-ESO-1 antigen was evaluated by monitoring mononuclear cells in patient peripheral blood, pre- and post-vaccine, by short-term in vitro sensitization, HLA-multimer staining and IFN-γ ELISpot analysis. RESULTS: Both CD3 T cells and CD163 myeloid cells were present in pre-vaccine tumors and PD-1 and PD-L1 expression was mainly found in the immune infiltrate. Despite the advanced stage of the disease, the vaccination induced systemic NY-ESO-1 specific CD8 T cells releasing IFN-γ in response to activation with the NY-ESO-1 peptide and an HLA-A2 positive neuroblastoma cell line. CONCLUSIONS: Our results indicate that vaccination with a tumor-associated peptide is able to boost NY-ESO-1-specific, functionally active T cells in advanced neuroblastoma patients with lymphocyte infiltration in their pre-vaccine tumors. TRIAL REGISTRATION: EudraCT #2006-002859-33.

Correction to: Results of nimotuzumab and vinorelbine, radiation and re-irradiation for diffuse pontine glioma in childhood.

The therapeutic experience reported in the paper was conceived after the use of nimotuzumab and radiotherapy (BSCPED-05 international multicentric trial, EUDRACT 2005-003100-11) in 2009 when we decided to explore the activity of the same combination plus vinorelbine (see the paper for the rationale).

Thyroid cancer in adolescents and young adults.

In adolescents and young adults, thyroid cancer accounts for 13% of all invasive neoplasms, being three times more frequent in females, but overdiagnosis and overtreatment are common. There are two therapeutic approaches, one radical and no longer preferred in all instances, and the other conservative. Permanent complications of surgery and metabolic irradiation can affect quality of life and carry an economic burden. The overall survival rate approaches 100% for patients with differentiated thyroid cancer regardless of the extent of treatment. Medullary thyroid carcinoma is a very different entity, occurring most frequently in the context of hereditary tumor susceptibility syndromes.

Front-line window therapy with cisplatin in patients with primary disseminated Ewing sarcoma: A study by the Associazione Italiana di Ematologia ed Oncologia Pediatrica and Italian Sarcoma Group.

The aim was to assess the activity of cisplatin (CDDP) in Ewing sarcoma (ES). The study consisted of front-line window therapy with CDDP 120 mg/sqm every 3 weeks for two courses in children and young adults with primary disseminated ES. Response was assessed using the Response Evaluation Criteria in Solid Tumours criteria, and Simon's two-stage design was applied. Twelve consecutive patients were enrolled in stage 1. Only one objective response was observed. Since the target response rate was not achieved, accrual was stopped and CDDP as a single agent in ES was judged unworthy of further assessment.

The Sooner the Better? How Symptom Interval Correlates With Outcome in Children and Adolescents With Solid Tumors: Regression Tree Analysis of the Findings of a Prospective Study.

BACKGROUND: The potential impact of diagnostic delays on patients' outcomes is a debated issue in pediatric oncology and discordant results have been published so far. We attempted to tackle this issue by analyzing a prospective series of 351 consecutive children and adolescents with solid malignancies using innovative statistical tools. METHODS: To address the nonlinear complexity of the association between symptom interval and overall survival (OS), a regression tree algorithm was constructed with sequential binary splitting rules and used to identify homogeneous patient groups vis-à-vis functional relationship between diagnostic delay and OS. RESULTS: Three different groups were identified: group A, with localized disease and good prognosis (5-year OS 85.4%); group B, with locally or regionally advanced, or metastatic disease and intermediate prognosis (5-year OS 72.9%), including neuroblastoma, Wilms tumor, non-rhabdomyosarcoma soft tissue sarcoma, and germ cell tumor; and group C, with locally or regionally advanced, or metastatic disease and poor prognosis (5-year OS 45%), including brain tumors, rhabdomyosarcoma, and bone sarcoma. The functional relationship between symptom interval and mortality risk differed between the three subgroups, there being no association in group A (hazard ratio [HR]: 0.96), a positive linear association in group B (HR: 1.48), and a negative linear association in group C (HR: 0.61). CONCLUSIONS: Our analysis suggests that at least a subset of patients can benefit from an earlier diagnosis in terms of survival. For others, intrinsic aggressiveness may mask the potential effect of diagnostic delays. Based on these findings, early diagnosis should remain a goal for pediatric cancer patients.