Single-cell transcriptomics reveals shared immunosuppressive landscapes of mouse and human neuroblastoma

BACKGROUND

High-risk neuroblastoma is a pediatric cancer with still a dismal prognosis, despite multimodal and intensive therapies. Tumor microenvironment represents a key component of the tumor ecosystem the complexity of which has to be accurately understood to define selective targeting opportunities, including immune-based therapies.

METHODS

We combined various approaches including single-cell transcriptomics to dissect the tumor microenvironment of both a transgenic mouse neuroblastoma model and a cohort of 10 biopsies from neuroblastoma patients, either at diagnosis or at relapse. Features of related cells were validated by multicolor flow cytometry and functional assays.

RESULTS

We show that the immune microenvironment of MYCN-driven mouse neuroblastoma is characterized by a low content of T cells, several phenotypes of macrophages and a population of cells expressing signatures of myeloid-derived suppressor cells (MDSCs) that are molecularly distinct from the various macrophage subsets. We document two cancer-associated fibroblasts (CAFs) subsets, one of which corresponding to CAF-S1, known to have immunosuppressive functions. Our data unravel a complex content in myeloid cells in patient tumors and further document a striking correspondence of the microenvironment populations between both mouse and human tumors. We show that mouse intratumor T cells exhibit increased expression of inhibitory receptors at the protein level. Consistently, T cells from patients are characterized by features of exhaustion, expressing inhibitory receptors and showing low expression of effector cytokines. We further functionally demonstrate that MDSCs isolated from mouse neuroblastoma have immunosuppressive properties, impairing the proliferation of T lymphocytes.

CONCLUSIONS

Our study demonstrates that neuroblastoma tumors have an immunocompromised microenvironment characterized by dysfunctional T cells and accumulation of immunosuppressive cells. Our work provides a new and precious data resource to better understand the neuroblastoma ecosystem and suggest novel therapeutic strategies, targeting both tumor cells and components of the microenvironment.

GCT-02. Imaging response assessment for Central Nervous System Germ Cell Tumours: consensus recommendations from the European Society for Paediatric Oncology Brain Tumour Group (SIOPE-BTG) and North American Children’s Oncology Group (COG)

BACKGROUND: Central nervous system (CNS) germ cell tumours (GCT) comprise a heterogeneous and relatively rare group of neoplasms. Improving the ability to conduct international clinical trials for CNS GCT requires use of homogeneous, common objective disease assessments and standardised response criteria. Currently, different criteria are employed between European and North American protocols for assessing radiological disease response. METHODS: An international working group of the European Society for Paediatric Oncology (SIOPE) Brain Tumour Group (BTG) and North American Children’s Oncology Group (COG) was therefore established to develop consensus recommendations for imaging response assessment for CNS GCT. The working group first reviewed existing literature and current practices and identified major challenges regarding imaging assessment. RESULTS: New clinical imaging standards were defined for the most common sites of intracranial GCT disease (suprasellar/pineal/bifocal), as well as for definition of loco-regional extension. In particular, clear standards were highlighted for definition of partial response (PR) and complete response (CR) to induction chemotherapy at different sites. Furthermore, growing teratoma syndrome (GTS) was clearly defined [apparent radiological increase in non-germinomatous GCT (NGGCT) size during induction chemotherapy despite normalising/normalised AFP/HCG markers – requiring surgery], to avoid such potential cases being classified as progressive disease (PD). CONCLUSION: This consensus will allow more consistent prospective neuroradiological evaluation of response to therapy for patients with CNS GCT and facilitate direct comparison of treatment outcomes across international studies. Ultimately, it may allow international trials to be developed and undertaken across a larger group of collaborating nations, which will be essential to answer many of the remaining questions for this rare but diverse group of tumours.

Imaging response assessment for CNS germ cell tumours: consensus recommendations from the European Society for Paediatric Oncology Brain Tumour Group and North American Children's Oncology Group

Homogeneous and common objective disease assessments and standardised response criteria are important for better international clinical trials for CNS germ cell tumours. Currently, European protocols differ from those of North America (the USA and Canada) in terms of criteria to assess radiological disease response. An international working group of the European Society for Paediatric Oncology Brain Tumour Group and North American Children's Oncology Group was therefore established to review existing literature and current practices, identify major challenges regarding imaging assessment, and develop consensus recommendations for imaging response assessment for patients with CNS germ cell tumours. New clinical imaging standards were defined for the most common sites of CNS germ cell tumour and for the definition of locoregional extension. These new standards will allow the evaluation of response to therapy in patients with CNS germ cell tumours to be more consistent, and facilitate direct comparison of treatment outcomes across international studies.

Voxel-wise supervised analysis of tumors with multimodal engineered features to highlight interpretable biological patterns

Background

Translation of predictive and prognostic image‐based learning models to clinical applications is challenging due in part to their lack of interpretability. Some deep‐learning‐based methods provide information about the regions driving the model output. Yet, due to the high‐level abstraction of deep features, these methods do not completely solve the interpretation challenge. In addition, low sample size cohorts can lead to instabilities and suboptimal convergence for models involving a large number of parameters such as convolutional neural networks.

Purpose

Here, we propose a method for designing radiomic models that combines the interpretability of handcrafted radiomics with a sub‐regional analysis.

Materials and methods

Our approach relies on voxel‐wise engineered radiomic features with average global aggregation and logistic regression. The method is illustrated using a small dataset of 51 soft tissue sarcoma (STS) patients where the task is to predict the risk of lung metastasis occurrence during the follow‐up period.

Results

Using positron emission tomography/computed tomography and two magnetic resonance imaging sequences separately to build two radiomic models, we show that our approach produces quantitative maps that highlight the signal that contributes to the decision within the tumor region of interest. In our STS example, the analysis of these maps identified two biological patterns that are consistent with STS grading systems and knowledge: necrosis development and glucose metabolism of the tumor.

Conclusions

We demonstrate how that method makes it possible to spatially and quantitatively interpret radiomic models amenable to sub‐regions identification and biological interpretation for patient stratification.

A high-risk retinoblastoma subtype with stemness features, dedifferentiated cone states and neuronal/ganglion cell gene expression

Retinoblastoma is the most frequent intraocular malignancy in children, originating from a maturing cone precursor in the developing retina. Little is known on the molecular basis underlying the biological and clinical behavior of this cancer. Here, using multi-omics data, we demonstrate the existence of two retinoblastoma subtypes. Subtype 1, of earlier onset, includes most of the heritable forms. It harbors few genetic alterations other than the initiating RB1 inactivation and corresponds to differentiated tumors expressing mature cone markers. By contrast, subtype 2 tumors harbor frequent recurrent genetic alterations including MYCN-amplification. They express markers of less differentiated cone together with neuronal/ganglion cell markers with marked inter- and intra-tumor heterogeneity. The cone dedifferentiation in subtype 2 is associated with stemness features including low immune and interferon response, E2F and MYC/MYCN activation and a higher propensity for metastasis. The recognition of these two subtypes, one maintaining a cone-differentiated state, and the other, more aggressive, associated with cone dedifferentiation and expression of neuronal markers, opens up important biological and clinical perspectives for retinoblastomas.

Efficacy and Safety of Proton Beam Therapy for Primary Optic Nerve Sheath Meningioma

Purpose

Management of optic nerve sheath meningiomas (ONSM) remains challenging. Photon radiation therapy (PhRT) is the most common treatment for sight-threatening ONSM. Proton beam therapy (PBT) is less commonly used because it is more expensive and because there are questions about its efficacy specifically in relation to ONSM. PBT has the theoretical advantage of reducing radiation exposure to adjacent structures. We report the visual outcome of patients with primary ONSM managed at the Fondation Ophtalmologique Adolphe de Rothschild, Paris, France, and treated with PBT at the Centre de Protonthérapie, Institut Curie, Orsay, France.

Methods

We conducted a retrospective review of all patients with primary ONSM who received PBT (either by itself or following surgery) between January 2006 and January 2019. Neuro-ophthalmic examinations were performed at presentation and after radiotherapy, and, when applicable, after surgery. Meningiomas were measured at the time of diagnosis and at each follow-up MRI examination.

Results

Sixty patients (50 women, 10 men; mean age, 45.2±11.1y) were included, of whom 29 underwent surgery. At presentation, 52 (87%) of them had decreased vision (average visual acuity: 0.6 logMAR). Fundus examination showed optic disc swelling (n=27; 46.5%), optic disc pallor (n=22; 37.9%), optic disc cupping (n=2; 3.4%), opto-ciliary shunt (n=8; 13.8%), or choroidal folds (n=5; 8.6%). Otherwise, it was unremarkable (n=7; 12.1%). After treatment, visual function was stable overall. Fundus examination showed pallor (n=47; 83.9%), swelling (n=3; 5.4%), or cupping (n=2; 3.4%) of the optic disc, or was unremarkable (n=5; 8.9%). The visual field of 8 patients worsened, while 3 developed asymptomatic retinal hemorrhages. Tumor shrunk significantly in 8 patients at 1 year after PBT and remained stable in size in all others. Patients with opto-ciliary shunts had significantly worse visual outcome than other patients. Retinal abnormalities were observed in 11 patients during follow-up.

Conclusion

PBT alone or in association with surgery appears to be a safe and efficient treatment for ONSM, reducing the tumor size and stabilizing visual function. The risk of developing radiation retinopathy seems to be higher when patients had upfront surgery.

Infantile Rhabdomyosarcomas With VGLL2 Rearrangement Are Not Always an Indolent Disease: A Study of 4 Aggressive Cases With Clinical, Pathologic, Molecular, and Radiologic Findings

VGLL2-rearranged rhabdomyosarcomas (RMS) are rare low-grade tumors with only favorable outcomes reported to date. We describe 4 patients with VGLL2-rearranged RMS confirmed by molecular studies, who experienced local progression and distant metastases, including 2 with fatal outcomes. Tumors were diagnosed at birth (n=3) or at 12 months of age (n=1), and were all localized at initial diagnosis, but unresectable and therefore managed with chemotherapy and surveillance. Metastatic progression occurred from 1 to 8 years from diagnosis (median, 3.5 y). Three patients experienced multimetastatic spread and one showed an isolated adrenal metastasis. At initial diagnosis, 3 tumors displaying bland morphology were misdiagnosed as fibromatosis or infantile fibrosarcoma and initially managed as such, while 1 was a high-grade sarcoma. At relapse, 3 tumors showed high-grade morphology, while 1 retained a low-grade phenotype. Low-grade primary tumors showed only very focal positivity for desmin, myogenin, and/or MyoD1, while high-grade tumors were heterogenously or diffusely positive. Whole-exome sequencing, performed on primary and relapse samples for 3 patients, showed increased genomic instability and additional genomic alterations (eg, TP53, CDKN2A/B, FGFR4) at relapse, but no recurrent events. RNA sequencing confirmed that high-grade tumors retained VGLL2 fusion transcripts and transcriptomic profiles consistent with VGLL2-rearranged RMS. High-grade samples showed a high expression of genes encoding cell cycle proteins, desmin, and some developmental factors. These 4 cases with distinct medical history imply the importance of complete surgical resection, and suggest that RMS-type chemotherapy should be considered in unresectable cases, given the risk of high-grade transformation. They also emphasize the importance of correct initial diagnosis.

[COVID-19 and patients with cancer: Experiment of a French comprehensive cancer center]

The emergence of the Coronavirus Disease 2019 (COVID-19) has caused profound upset in health systems around the world. As cancer patients seem to be at greater risk, the organization of oncological care had to be adapted. We first report the progress of the "first wave" of COVID-19 at the Institut Curie, a French comprehensive cancer center, by describing the measures implemented to limit the risk of transmission of COVID-19 while ensuring as much as possible the continuation of anticancer treatments. Then, we present the results of a prospective institutional database in which the characteristics and outcome of our patients with cancer and suffering from COVID-19 were collected. From March 13 to April 25, 2020, 141 patients followed at Institut Curie for cancer developed COVID-19, of which 26 (18%) died from it. The minimum incidence of COVID-19 in Institut Curie is estimated at 1.4% over this period. No risk factors for developing a severe form of COVID-19 related to cancer have been identified. Cancer patients do not appear to be at greater risk of developing COVID-19, nor of having a more severe form than the general population. With the current increase of COVID-19 cases, it seems essential to share the experience already acquired to minimize the impact of this crisis on the long-term outcome of patients followed for cancer.

Chest computed tomography findings for a cohort of children with pulmonary Langerhans cell histiocytosis

OBJECTIVE

This study was undertaken to describe the spectrum of lung computed-tomography (CT) findings in children with pulmonary Langerhans cell histiocytosis (PLCH) and to evaluate for this population the CT-scan nodule and cyst scores proposed by adult pulmonologists at diagnosis and during follow-up.

METHODS

Among 175 children with PLCH identified in the French national population-based Langerhans cell histiocytosis cohort, 60 were retrospectively selected by the availability of CT for a central review by three pediatric radiologists. These 60 patients are representative of childhood PLCH for almost all clinical aspects, except a lower percentage of risk organ involvement (38% vs 54%; P = 0.05).

RESULTS

The 60 children's chest CT scans (n = 218) were reviewed. At diagnosis, 63% of them had nodules, 53% had cysts, and 29% had both. The percentages of patients with nodules or cysts increased from diagnosis to peak disease activity, respectively, from 63% to 73% and from 53% to 66%. The costophrenic angle was involved in 71%. Patients with pneumothorax (25%) had a higher median cyst score. Alveolar consolidation was observed in 34%. Patients with low CT-scan nodule and cyst scores had no long-term pulmonary sequelae.

CONCLUSIONS

Well-known characteristics of adult PLCH (nodules and cysts) were observed in children. The chest CT scores proposed by adult pulmonologists could easily be applied to childhood PLCH. Lesions in children, unlike those in adults, are frequently located near the costophrenic angles. Alveolar consolidation might be considered an atypical feature of childhood PLCH.

Liver metastasis at diagnosis in children with nephroblastoma enrolled in SIOP2001 protocol: A French multicentric study

BACKGROUND

Liver metastases are rare in children with Wilms tumor (WT), and their impact on the outcome is unclear.

PATIENTS AND METHODS

The French cohort of patients with WT presenting liver metastases at diagnosis and enrolled in the International Society of Pediatric Oncology (SIOP) 2001 study was reviewed.

RESULTS

From 2002 to 2012, 906 French patients were enrolled in the SIOP2001 trial. Among them, 131 (14%) presented with stage IV WT and 18 (1.9%) had liver metastases at diagnosis. Isolated liver metastases were displayed in four of them. After preoperative chemotherapy, persistent liver disease was reported in 14/18 patients, and 13 of them underwent metastasectomy after nephrectomy. In resected liver lesions, the same histology of the primary tumor was reported for three patients, blastemal cells without anaplasia were identified in one patient with DA-WT, and post-chemotherapy necrosis/fibrosis was identified for the other 10 patients. For the four patients who had liver and lung surgery, both sites had nonviable cells with post-chemotherapy necrosis/fibrosis. Six patients had hepatic radiotherapy. Sixteen patients achieved primary complete remission and were alive at the last follow-up (median follow-up: 6.4 years). The only two deceased patients presented diffuse anaplasia histology. The five-year EFS and OS were 83% (60%-94%) and 88% (66%-97%), respectively.

CONCLUSION

Liver involvement does not appear to be an adverse prognostic factor in metastatic WT. The role of hepatic surgery and radiotherapy remains unclear, and should be carefully considered in case of persistent liver metastases, according to histology and radiological response to other metastatic sites.

Tag-n-trak study: Preliminary analysis of an unselected biobank tumors with NTRK fusion transcript, the French SFCE society contribution

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Background: NTRK ( Neurotrophic receptor tyrosine kinase) fusion transcript was initially described in infantile fibrosarcoma (IFS) and is now known to be present in many other rare types of tumor with a lower incidence. The main objective of the study is to describe the presentation and outcome of unselected tumors with NTRK fusion transcript (NTRK-FTT) to better consider the role of TRK inhibitors (TRKi) in such entities. Methods: We selected patients (pts) from the Institut Curie biobank (adults and children) with NTRK-FTT and which were assessed by RT-qPCR then RNA sequencing in a prospective or retrospective process, between 2001 and 2019. Results: We identified 62 NTRK-FTT among 2119 screened tumors (2.2 cases/year with RT-qPCR and 6.9 cases/year with RNA seq after 2016), NTRK3 (44 cases) (including 41 NTRK3-ETV6), NTRK2 (9) or NTRK1 (9). Most of pts had under 2 years (y) (74%) and only 7 pts were adults. We report preliminary analysis of clinical observation for the first 27 pts. Median age was 0.4 y [0-60.2]. Pathologic diagnosis was IFS (12 cases), various CNS tumors (4), atypical teratoid rhabdoid tumor (1), myofibroblastic inflammatory tumor (2), benign tumors (3), cellular congenital mesoblastic nephroma (2), lipofibromatosis like neural tumor, myxoïd liposarcoma, unclassifiable sarcoma (1 each). Two pts had metastatic tumors. Among all, 22 had surgery (1 mutilating), 15 chemotherapy, 4 radiotherapy, and 5 received TRKi, as second line treatment (2 pts) or ≥ third line (3 pts). After a median follow-up of 50 months [range, 1-155], 20/27 pts remained in complete remission, 3 had stable residue, and 4 had progressive disease (associated to 1 disease-related and 1 toxic deaths). Five-year OS is 88% [95%CI, 73.5-100] and 5y-EFS 59.5% [95%CI, 41.7-84.9]. Conclusions: This descriptive study showed that NTRK-FTT is rare (2.9%), encompasses a variety of different histotypes (n = 14). Systematic RNA sequencing allowed to depict 3.5 times more NTRK-FTT than targeted RT-qPCR. Overall outcome is favorable despite frequent tumor events. According to tumor type and the uncertainties regarding the long-term side effects of TRKi, the benefit/risk ratio must be carefully evaluated before using these drugs in first line.

Outcome of patients with stage IV high-risk Wilms tumour treated according to the SIOP2001 protocol: A report of the SIOP Renal Tumour Study Group

INTRODUCTION

High-risk (HR) metastatic (stage IV) Wilms tumours (WTs) have a particular poor outcome.

METHODS

Here, we report the results of HR (diffuse anaplastic [DA] or blastemal type [BT]) stage IV WT treated patients according to the HR arm in the SIOP2001 prospective study.

RESULTS

From January 2002 to August 2014, 3559 patients with WT were included in the SIOP2001 trial. Among the 525 patients (15%) with metastatic WT, 74 (14%) had stage IV HR-WT. The median age at diagnosis was 5.5 years (range: 1.4-18.3). Thirty-four patients (47%) had BT-WT and 40 (53%) had DA-WT. Five-year event-free survival rates were 44 ± 17% and 28 ± 15% for BT-WT and DA-WT, respectively (p = 0.09). Five-year overall survival rates were 53 ± 17% and 29 ± 16% for BT-WT and DA-WT, respectively (p = 0.03). Metastatic complete response after preoperative treatment was significantly associated with outcome in univariate and multivariate analyses (hazards ratio = 0.3; p = 0.01). Postoperative radiotherapy of metastatic sites might also be beneficial. Forty-three of 74 patients experienced a relapse or progression predominantly in the lungs (80%). The median time to relapse/progression after diagnosis was 7.3 months (range: 1.6-33.3) and 4.9 months (range: 0.7-28.4) for BT-WT and DA-WT, respectively (p = 0.67). This is the first prospective evidence of inferior survival of stage IV BT-WT as compared with historical intermediate-risk WT. Survival of patients with stage IV DA-WT has not improved compared to the previous SIOP93-01 study.

CONCLUSION

These results call for new treatment approaches for patients with HR stage IV WT.

Multidisciplinary surgical strategy for dumbbell neuroblastoma: A single-center experience of 32 cases

INTRODUCTION

Prognosis of dumbbell neuroblastoma (NBL) is mainly determined by the sequelae induced by the tumor itself and the neurosurgical approach. However, after primary chemotherapy, surgical management of the residual tumor, especially the spinal canal component, remains controversial.

METHODS

We conducted a single-center retrospective cohort study over the last 15 years (2002-2017) including patients treated for NBL with spinal canal extension focusing on timing and type of surgery, complications, and functional and oncological follow-up.

RESULTS

Thirty-two children (14 M, 18 F) were managed for NBL, with the majority (26) presenting with NBL stroma poor while four had ganglioneuroblastoma intermixed, one nodular, and one ganglioneuroma. All but two patients received neoadjuvant chemotherapy. Upfront laminotomy for spinal cord decompression was performed in two patients; nine patients had extraspinal surgery with a follow-up neurosurgical procedure in seven cases; eight patients had initial neurosurgery followed by an extraspinal procedure, while six patients underwent a combined multidisciplinary approach. With a median follow up of 3.6 years (0.1-14.9), 29 patients (90.6) are alive and two out of three (19, 65.5%) have functional sequelae.

CONCLUSION

Patients with NBL with persistent spinal canal extension of the tumor after neoadjuvant chemotherapy treated at our center had outcomes that compare favorably with the literature. This is likely due to the multidisciplinary approach to optimal surgical strategy and continuous evaluation of the respective risks of tumor progression. Neurological disability results from initial spinal cord compression or the radicular sacrifice required for tumor resection.

Antitumor immune response induced by NBTXR3 activated by radiotherapy

e14609

Background: Radiotherapy (RT) can prime an anti-tumor immune response. Unfortunately, this response rarely generates total tumor destruction and abscopal effect. When activated by RT, intratumorally (IT) administered hafnium oxide nanoparticles (NBTXR3) locally increase radiation dose deposit and tumor cell death compared to RT alone. We hypothesized that NBTXR3 + RT could enhance the anti-tumor immune response, both in mice and humans. Methods: Murine CT26 cells were injected in both flanks of immunocompetent mice. When tumor volume reached 50-120mm3, NBTXR3 (or vehicle) was injected IT in right flank tumors only, then irradiated (3x4Gy). Mice were sacrificed when tumors reached 800mm3. Alternatively, tumors were collected 3 days after last RT fraction and immune cell infiltrates analyzed by immunohistochemistry (IHC). Patients (pts) with locally advanced Soft Tissue Sarcoma (STS) (NCT02379845) received NBTXR3 + RT or RT alone. Pre- and post-treatment (biopsy and resection, respectively) tumor tissues from pts were analyzed by IHC and Digital Pathology for immune biomarkers ( > 16 pts per arm). Results: In mice, IHC analyses showed an increase of CD8+ T cells infiltrates in both flanks of mice treated with NBTXR3+RT, while this was not observed in animals treated with RT alone. Furthermore, ICH analysis of post- vs pre-treatment samples from STS pts showed a marked increase of CD8+ and PD1 biomarkers for pts treated with NBTXR3 + RT, while no differences were seen for pts treated with RT alone. Conclusions: NBTXR3 + RT markedly changes the tumor immune profile in a similar manner in mice and pts with STS. We hypothesize that this adaptive immune response could help convert a local tumor microenvironment to a “hot” phenotype and thus improve the efficacy of immune checkpoint inhibitors. These results led us to investigate the safety and systemic effect of NBTXR3 activated by stereotactic ablative RT (SABR) in combination with anti-PD-1 antibody in pts with locoregionally recurrent or metastatic (to lung or liver) Head and Neck squamous cell carcinoma HNSCC, as well as in metastatic non-small cell lung cancer (NSCLC) and liver metastasis patients [NCT03589339].

Long-term results of the transmanubrial osteomuscular-sparing approach for pediatric tumors

BACKGROUND

The complete and safe resection of pediatric cervicothoracic tumors, mostly represented by neurogenic tumors, remains a surgical challenge because of the complex anatomy of this region. The transmanubrial osteomuscular-sparing approach (TOSA) is an alternative to isolated or combined cervical and thoracic approaches enabling the control of supra-aortic vessels and nerves through the thoracic inlet.

METHODS

We retrospectively reviewed the tumor characteristics, completeness of resection, morbidity, and long-term outcome of patients with cervicothoracic tumors removed by TOSA between 2000 and 2012 in our institution.

RESULTS

Thirteen patients (7 males, 6 females) underwent surgery at a median age of 72 months (4-188) for neuroblastoma (n = 6), ganglioneuroblastoma (n = 3), rhabdoid tumor (n = 1), melanotic schwannoma (n = 1), chordoma (n = 1), and malignant peripheral nerve sheath tumor in one patient with type 1 neurofibromatosis. The median duration of the procedure was 215 minutes (110-315). Two children presented with postoperative chylothorax that resolved spontaneously. The median duration of hospitalization was 7 days (4-22). At a median follow-up of 39 months (2-159), four patients had died of metastatic relapse (n = 2), locoregional progression (n = 1), and chemotoxicity (n = 1). The patient with melanotic schwannoma was lost to follow-up after a local relapse at 5 months. Long-term morbidity revealed homolateral Claude-Bernard Horner sign and upper limb vasomotor dysfunction in disease-free patients due to mandatory resection of the stellate ganglia.

CONCLUSIONS

TOSA is a valuable surgical approach for all cervicothoracic tumors with acceptable long-term morbidity when compared with its complexity. We can therefore recommend TOSA for tumors involving the thoracic inlet.

Childhood CT scans and cancer risk: impact of predisposing factors for cancer on the risk estimates

To investigate the role of cancer predisposing factors (PFs) on the associations between paediatric computed tomography (CT) scan exposures and subsequent risk of central nervous system (CNS) tumours and leukaemia. A cohort of children who underwent a CT scan in 2000-2010 in 23 French radiology departments was linked with the national childhood cancers registry and national vital status registry; information on PFs was retrieved through hospital discharge databases. In children without PF, hazard ratios of 1.07 (95% CI 0.99-1.10) for CNS tumours (15 cases) and 1.16 (95% CI 0.77-1.27) for leukaemia (12 cases) were estimated for each 10 mGy increment in CT x-rays organ doses. These estimates were similar to those obtained in the whole cohort. In children with PFs, no positive dose-risk association was observed, possibly related to earlier non-cancer mortality in this group. Our results suggest a modifying effect of PFs on CT-related cancer risks, but need to be confirmed by longer follow-up and other studies.

Relapse after localized rhabdomyosarcoma: Evaluation of the efficacy of second-line chemotherapy

PURPOSE

About one-third of patients with rhabdomyosarcoma relapse despite appropriate treatment and experience a poor outcome. Little meaningful improvement in the outcome of this disease has been observed over the last 30 years. There is no clear international recommendation concerning the use of salvage chemotherapy at relapse. A retrospective multicenter analysis was therefore conducted to analyze the efficacy of various second-line chemotherapy regimens in this setting.

METHODS

Forty-nine patients under the age of 18, with initially localized rhabdomyosarcoma, who relapsed after first complete remission, treated in three SFCE centers (Société Française des Cancers de l'Enfant) between 1995 and 2013, were analyzed.

RESULTS

First relapse occurred after a median interval of 22 months and remained localized in 71.4% of cases. All patients received second-line chemotherapy with an overall response to this salvage therapy of 39.1%. Best specific response rates were 73.3 and 42.9% for carboplatin/epirubicin/vincristine-ifosfamide/vincristine/etoposide (CEV/IVE) (15 patients) and vincristine/irinotecan ± temozolomide (VI[T]) (seven patients), respectively. Overall, 40 patients (81.6%) were then eligible for delayed local treatment (surgery and/or radiotherapy) and 30 of them (61.2%) achieved second complete remission. After a median follow-up of 5.4 years since the diagnosis of first relapse, 5-year overall survival is 49.4% (95% CI: 34.2-64.6).

CONCLUSION

Salvage chemotherapy plays a central role in the management of patients with relapsed rhabdomyosarcoma. CEV/IVE and VI(T) regimens can be recommended as neoadjuvant chemotherapy before local treatment for patients with relapsed rhabdomyosarcoma.

Bone marrow imaging: follow-up after treatment in cancer patients

The evaluation of bone marrow of patients treated for cancer is complicated by age-related changes in the distribution of normal (red) and fatty (yellow) marrow and by the changes induced by treatments. The treatments used in oncology modify pathological marrow but also normal marrow and may sometimes lead to complications. The knowledge of bone marrow physiological status and post-therapeutic patterns is important for the interpretation of marrow disorders and effects of therapy.

Are the studies on cancer risk from CT scans biased by indication? Elements of answer from a large-scale cohort study in France

BACKGROUND

Recent epidemiological results suggested an increase of cancer risk after receiving computed tomography (CT) scans in childhood or adolescence. Their interpretation is questioned due to the lack of information about the reasons for examination. Our objective was to estimate the cancer risk related to childhood CT scans, and examine how cancer-predisposing factors (PFs) affect assessment of the radiation-related risk.

METHODS

The cohort included 67,274 children who had a first scan before the age of 10 years from 2000 to 2010 in 23 French departments. Cumulative X-rays doses were estimated from radiology protocols. Cancer incidence was retrieved through the national registry of childhood cancers; PF from discharge diagnoses.

RESULTS

During a mean follow-up of 4 years, 27 cases of tumours of the central nervous system, 25 of leukaemia and 21 of lymphoma were diagnosed; 32% of them among children with PF. Specific patterns of CT exposures were observed according to PFs. Adjustment for PF reduced the excess risk estimates related to cumulative doses from CT scans. No significant excess risk was observed in relation to CT exposures.

CONCLUSIONS

This study suggests that the indication for examinations, whether suspected cancer or PF management, should be considered to avoid overestimation of the cancer risks associated with CT scans.

Has the percutaneous vertebroplasty a role to prevent progression or local recurrence in spinal metastases of breast cancer?

OBJECTIVE

To evaluate the effectiveness of percutaneous vertebroplasty (PV) on the prevention of progression or local recurrence in patients with spinal metastases from breast cancer.

MATERIALS AND METHODS

Retrospective study on 55 patients between 27-78 years of age (mean age: 55 years) treated for metastatic breast cancer in the same institution (Curie institute, Paris, France), who underwent percutaneous vertebroplasty (PV) (number of vertebrae treated=137) for spinal metastases from January 2000 to December 2009 at the Pitié-Salpêtrière hospital. Statistical correlation between the local tumor progression/recurrence, and the presence of an epidural or a paravertebral metastatic extension at diagnosis, the rate of cement filling the lesion (<50%, ≥50% but incomplete, complete/almost complete) and radiotherapy was evaluated using Chi(2) and Fisher's exact test.

RESULTS

The rate of local tumor progression/recurrence of the vertebrae treated by vertebroplasty was 14% (19/137). No statistically significant correlation between either the rate of cement filling of the lesion, or the presence of an epidural or paravertebral metastatic extension, and progression/local recurrence after vertebroplasty was found. No influence of radiotherapy in preventing local progression/recurrence was noted. Distant new bone metastases were observed in 47 out of 55 patients (86%).

CONCLUSION

The low rate of local tumor progression/recurrence after a vertebroplasty may support the hypothesis of an antitumor effect of the cement.

Fine-needle aspiration in desmoplastic small round cell tumor: a report of 10 new tumors in 8 patients with clinicopathological and molecular correlations with review of the literature

BACKGROUND

Desmoplastic small round cell tumor (DSRCT) is a rare round cell sarcoma entity characterized by a specific t(11;22)(p13;q12) translocation, usually intra-abdominal localization and an aggressive clinical outcome. To date, only 35 DSRCT cases diagnosed by fine-needle aspiration have been described.

METHODS

This study reports the cytological diagnosis of DSRCT. Ten tumors from 8 patients were sampled for diagnosis and analyzed to search the characteristic translocation using fluorescence in situ hybridization or reverse transcription polymerase chain reaction methods.

RESULTS

Smears were always hypercellular and consisted of nonspecific round cell sarcoma. Nuclei were polymorphic round, kidney-, or heart-shaped. Nuclear molding was usually present. Paranuclear cytoplasmic densities were obvious and noted in 7 cases. Cytonuclear atypia, mitotic figures, numerous crushed nuclei, and apoptosis were frequently seen. Purple-stained stroma was present in 8 cases (ranging from few connective tissue fragments to large hyalinized deposits). Molecular studies based on cytological aspirates were performed in 8 patients. The presence of the fusion gene EWSR1-WT 1 transcript was identified in all, which confirmed the diagnosis of DSRCT.

CONCLUSIONS

Smears showing poorly differentiated round cells associated with cytoplasmic densities and connective stoma, in a specific clinical context, young adult age, intra-abdominal localization, suggestive immunocytochemical profile, and a unique cytogenetic abnormality are highly specific and allow an accurate diagnosis of DSRCT.

Malformations, genetic abnormalities, and Wilms tumor

BACKGROUND

Wilms Tumor (WT) can occur in association with tumor predisposition syndromes and/or with clinical malformations. These associations have not been fully characterized at a clinical and molecular genetic level. This study aims to describe clinical malformations, genetic abnormalities, and tumor predisposition syndromes in patients with WT and to propose guidelines regarding indications for clinical and molecular genetic explorations.

PROCEDURE

This retrospective study analyzed clinical abnormalities and predisposition syndromes among 295 patients treated for WT between 1986 and 2009 in a single pediatric oncological center.

RESULTS

Clinically identified malformations and predisposition syndromes were observed in 52/295 patients (17.6%). Genetically proven tumor predisposition syndromes (n = 14) frequently observed were syndromes associated with alterations of the chromosome WT1 region such as WAGR (n = 6) and Denys-Drash syndromes (n = 3), syndromes associated with alterations of the WT2 region (Beckwith-Wiedeman syndrome, n = 3), and Fanconi anemia (n = 2). Hemihypertrophy and genito-urinary malformations (n = 12 and n = 16, respectively) were the most frequently identified malformations. Other different syndromes or malformations (n = 10) were less frequent. Median age of WT diagnosis was significantly earlier for children with malformations than those without (27 months vs. 37 months, P = 0.0009). There was no significant difference in terms of 5-year EFS and OS between WT patients without or with malformations.

CONCLUSIONS

The frequency of malformations observed in patients with WT underline the need of genetic counseling and molecular genetic explorations for a better follow-up of these patients, with a frequently good outcome. A decisional tree, based on clinical observations of patients with WT, is proposed to guide clinicians for further molecular genetic explorations.

Risk-adapted therapy for infantile myofibromatosis in children

BACKGROUND

Infantile myofibromatosis is characterized by proliferation of benign fibrous tumors arising in skin, subcutaneous tissue, muscle, or bone. Solitary and multicentric forms are described. Few reports are available in the pediatric population.

PROCEDURE

To improve the knowledge of this rare tumor in infants, the authors present a series of all cases of infantile myofibromatosis treated in their institution over a 9-year period in order to propose treatment guidelines based on their experience and a review of the literature.

RESULTS

The authors report a series of 9 cases, 8 solitary forms and 1 multicentric form with visceral involvement treated from 2000 to 2009. Median age was 10 months (range: 2 days-14 years). Six patients with solitary forms underwent primary surgical resection leading to remission. Only biopsy was performed in 1 case, followed by tumor regression with no recurrence. The last patient with a solitary form was treated by chemotherapy and then surgery allowing remission. The patient with a multicentric form presented complete regression of tumors after 1 year of vinblastine and methotrexate combination chemotherapy.

CONCLUSIONS

Infantile myofibromatosis is a rare soft tissue tumor mainly concerning infants. Surgery is the treatment of choice for solitary forms when excision is possible. Close follow-up may be proposed in the case of inoperable sites. In multicentric life-threatening forms, chemotherapy promotes tumor regression and the vinblastine and methotrexate combination is effective with few long-term adverse effects.

Surgery of ovarian tumors in children

Surgery of ovarian tumors in children requires a good knowledge of these lesions. Complete resection is mandatory for malignant lesions, and in the case of benign tumors preservation of healthy ovarian tissue is crucial. Diagnosis is based on clinical features (age and hormonal status), imaging and tumor marker levels. Laparoscopy is of great help in making a diagnosis and staging when the lesion is malignant. Laparotomy by a supra-pubic approach is, however, the only way to ensure a safe treatment of the lesion by avoiding any risk of tumor spillage, which constitutes a chance loss. Surgical treatment consists of complete ovariectomy for a malignant tumor and partial ovariectomy when the lesion is surely benign. Preservation of fertility is based on conservative surgery for uni- or bilateral benign lesions, and may be discussed in some selected cases of bilateral malignant tumors. When the remaining ovarian tissue predicts precocious ovarian failure, ovarian tissue or oocyte cryopreservation may be proposed to patients and their families.

Opsoclonus-myoclonus in children associated or not with neuroblastoma

OBJECTIVE

To compare the clinical data at diagnosis, treatment and neurological outcome in 34 children with opsoclonus-myoclonus syndrome (OMS) associated with a detected neuroblastoma or not.

STUDY DESIGN

This is a multicentric retrospective study of 34 children presenting with OMS from four pediatric centers diagnosed between 1988 and 2008.

RESULTS

Twenty-two patients had OMS associated with a neuroblastoma. These patients all had neuroblastomas with favourable prognostic features; all underwent surgery, six received chemotherapy. Twelve children had OMS without a detected neuroblastoma. For OMS, the main treatment in all children was corticotherapy (n=33), but immunoglobulins (n=13), cyclophosphamide (n=4) and rituximab (n=4) were also given. In the 27 OMS patients with or without neuroblastoma whose follow up was greater than two years, the neurological outcome was evaluated: 59.3% had neurological sequelae, including motor, praxic and/or language sequelae (n=9), persistent ataxia (n=6) and moderate motor deficit (n=3). No significant difference in neurological outcome was noted between the two patient groups.

CONCLUSION

Our retrospective study provides further evidence that OMS with or without a detected neuroblastoma is the same disease, whose major challenges are the neurological sequelae. An international collaboration is required to improve the knowledge about OMS, the treatment and the outcome in this rare disorder.

[Differential diagnosis of retinoblastoma: a retrospective study of 486 cases]

OBJECTIVES

Detail the most frequent problems encountered in the differential diagnosis of retinoblastoma.

PATIENTS

and method: We conducted a retrospective study on the children referred to the Curie Institute for suspicion of retinoblastoma between 2000 and 2006. Diagnosis was made by fundus examination using the indirect ophthalmoscope, ultrasonography, and MRI.

RESULTS

Of the 486 children seen during this period, 408 had unilateral or bilateral retinoblastoma and 78 (16%) had another lesion: Coats disease (20 children, 25%), congenital malformations (23 children, 30%; coloboma, PHPV, microphthalmia, isolated or associated with retinal dysplasia), other tumors (10 children, 13%; astrocytomas and medulloepithelioma), combined hamartomas (six children, 8%), inflammatory diseases (six children, 8%) (Toxocara canis, cat scratch eye disease, or toxoplasmosis), and other diseases (13 children, 16%; corneal opacities, congenital cataract, or retinal detachment).

DISCUSSION

Compared to previous series, this study shows the proportion of erroneous diagnosis has lowered (16%) compared to earlier studies by Balmer (1986; 30%), and Shields (1991; 42%). No cases of retinopathy of prematurity were seen in our series, demonstrating that screening is good or of a lower frequency in France. The frequency of PHPV has dropped. Coats disease remains a frequent and sometimes difficult diagnosis to make, particularly in advanced stages of the disease.

Radiation and chemotherapy combination for nasopharyngeal carcinoma in children: Radiotherapy dose adaptation after chemotherapy response to minimize late effects

OBJECTIVES

To retrospectively report the clinical and therapeutic features of children with nasopharyngeal carcinoma (NPC) treated by chemotherapy and doses adapted of radiotherapy.

PATIENTS AND METHODS

From 1978 to 2005, 34 children were treated for NPC. All histologic and/or cytologic samples and CT scans were reviewed. Cervical nodal irradiation was reduced (<50 Gy) in the case of a good response to chemotherapy (>/=90% of initial tumor volume).

RESULTS

Thirty-two children had metastatic cervical nodes and one child had systemic metastases at diagnosis. All children had AJJC-TNM Stage IV. Thirty-one children received neoadjuvant chemotherapy with various regimens. The overall chemotherapy response rate was 78%. Fifteen patients had cervical nodal irradiation dose reduced: Median 47 Gy (range: 45-50). Nasopharyngeal radiotherapy was delivered at a dose of 59.4 Gy (range: 45-66). Local and distant failure rates were 10% and 18%, respectively. The 5-year overall survival was 73 +/- 8% and the event-free survival (EFS) was 75 +/- 8%.

CONCLUSIONS

The overall prognosis was not influenced by TNM status, dose of local radiotherapy delivered or response to initial chemotherapy, but EFS was better in patients with a good response to chemotherapy. The cervical local failure rate was low despite radiotherapy dose reduction in the case of a good response to neoadjuvant chemotherapy. We also propose a reduction of nasopharyngeal radiation (</=50 Gy) in the case of good response to initial chemotherapy.

Imaging of sacral tumours

All components of the sacrum (bone, cartilage, bone marrow, meninges, nerves, notochord remnants, etc.) can give rise to benign or malignant tumours. Bone metastases and intraosseous sites of haematological malignancies, lymphoma and multiple myeloma are the most frequent aetiologies, while primary bone tumours and meningeal or nerve tumours are less common. Some histological types have a predilection for the sacrum, especially chordoma and giant cell tumour. Clinical signs are usually minor, and sacral tumours are often discovered in the context of nerve root or pelvic organ compression. The roles of conventional radiology, CT and MRI are described and compared with the histological features of the main tumours. The impact of imaging on treatment decisions and follow-up is also reviewed.

Cyto-histological correlations in primary, recurrent and metastatic rhabdomyosarcoma: the institut Curie's experience

To determine diagnostic cytomorphologic features of rhabdomyosarcoma (RMS) on fine-needle aspiration (FNA) material, the cytologic material and corresponding histologic slides of 180 tumors obtained from 109 patients were reviewed. Fifty eight (32.2%) tumors were primary, 34 (18.9%) recurrent, and 88 (48.9%) metastatic. A review of original cytology reports revealed that 176 of 180 (97.8%) tumors were either diagnosed accurately or as round cell sarcoma, while 3 (1.7%) were reported as suspicious. In one case (0.5%), the material was unsatisfactory. No false negative samples were seen. When FNA morphology was correlated with different histological subtypes, the alveolar subtype RMSs were more cellular than the nonalveolar ones (91.4% vs. 64.9%). Similarly, alveolar subtype RMSs compared with nonalveolar ones exhibited more rhabdomyoblastic cells (77.1% vs. 52.7%), alveolar structures (67.6% vs. 10.8%), giant, multinucleated cells (22.9% vs. 6.7%), mitotic figures (57.1% vs. 18.9%), and cyto-nuclear atypia (77.1% vs. 43.2%). Inversely, spindle-shaped cells were more frequently seen in nonalveolar versus alveolar RMSs (37.8% vs. 20.9%).