Rapid, complete and sustained tumour response to the TRK inhibitor larotrectinib in an infant with recurrent, chemotherapy-refractory infantile fibrosarcoma carrying the characteristic ETV6-NTRK3 gene fusion.

BACKGROUND: The ETV6-NTRK3 gene fusion is present in the majority of cases of infantile fibrosarcoma (IFS) and acts as a potent oncogenic driver. We report the very rapid, complete, and sustained response of an advanced, chemotherapy-refractory, recurrent IFS to targeted treatment with the oral tropomyosin receptor kinase (TRK) inhibitor larotrectinib. PATIENT AND METHODS: A male infant born with a large congenital IFS of the tongue had the tumour surgically resected at age 4 days. Within 2 months, he developed extensive lymph node recurrence that progressed during two cycles of vincristine-doxorubicin-cyclophosphamide chemotherapy. At screening, a large right cervical mass was clinically visible. Magnetic resonance imaging (MRI) revealed bilateral cervical and axillary lymph node involvement as well as infiltration of the floor of the mouth. The largest lesion measured 5.5×4.5×4.4 cm (ca. 55 cm3). The patient started outpatient oral larotrectinib at 20 mg/kg twice daily at age 3.5 months. RESULTS: After 4 days on treatment, the parents noted that the index tumour was visibly smaller and softer. The rapid tumour regression continued over the following weeks. On day 56 of treatment, the first scheduled control MRI showed the target lesion had shrunk to 1.2×1.2×0.8 cm (ca. 0.6 cm3), corresponding to a complete response according to the Response Evaluation Criteria In Solid Tumors version 1.1. This response was maintained over subsequent follow-up visits, and on day 112 at the second control MRI the target lymph node was completely normal. At last follow-up, the disease remained in complete remission after 16 months on larotrectinib, with negligible toxicity and no safety concerns. CONCLUSION(S): Selective TRK inhibition by larotrectinib offers a novel, highly specific and highly effective therapeutic option for IFS carrying the characteristic ETV6-NTRK3 gene fusion. Its use should be considered when surgery is not feasible. (NCT02637687).

Rapid, complete and sustained tumour response to the TRK inhibitor larotrectinib in an infant with recurrent, chemotherapy-refractory infantile fibrosarcoma carrying the characteristic ETV6-NTRK3 gene fusion.

BACKGROUND: The ETV6-NTRK3 gene fusion is present in the majority of cases of infantile fibrosarcoma (IFS) and acts as a potent oncogenic driver. We report the very rapid, complete, and sustained response of an advanced, chemotherapy-refractory, recurrent IFS to targeted treatment with the oral tropomyosin receptor kinase (TRK) inhibitor larotrectinib. PATIENT AND METHODS: A male infant born with a large congenital IFS of the tongue had the tumour surgically resected at age 4 days. Within 2 months, he developed extensive lymph node recurrence that progressed during two cycles of vincristine-doxorubicin-cyclophosphamide chemotherapy. At screening, a large right cervical mass was clinically visible. Magnetic resonance imaging (MRI) revealed bilateral cervical and axillary lymph node involvement as well as infiltration of the floor of the mouth. The largest lesion measured 5.5×4.5×4.4 cm (ca. 55 cm3). The patient started outpatient oral larotrectinib at 20 mg/kg twice daily at age 3.5 months. RESULTS: After 4 days on treatment, the parents noted that the index tumour was visibly smaller and softer. The rapid tumour regression continued over the following weeks. On day 56 of treatment, the first scheduled control MRI showed the target lesion had shrunk to 1.2×1.2×0.8 cm (ca. 0.6 cm3), corresponding to a complete response according to the Response Evaluation Criteria In Solid Tumors version 1.1. This response was maintained over subsequent follow-up visits, and on day 112 at the second control MRI the target lymph node was completely normal. At last follow-up, the disease remained in complete remission after 16 months on larotrectinib, with negligible toxicity and no safety concerns. CONCLUSION(S): Selective TRK inhibition by larotrectinib offers a novel, highly specific and highly effective therapeutic option for IFS carrying the characteristic ETV6-NTRK3 gene fusion. Its use should be considered when surgery is not feasible. (NCT02637687).

Genomic profiling of Acute lymphoblastic leukemia in ataxia telangiectasia patients reveals tight link between ATM mutations and chromothripsis.

Recent developments in sequencing technologies led to the discovery of a novel form of genomic instability, termed chromothripsis. This catastrophic genomic event, involved in tumorigenesis, is characterized by tens to hundreds of simultaneously acquired locally clustered rearrangements on one chromosome. We hypothesized that leukemias developing in individuals with Ataxia Telangiectasia, who are born with two mutated copies of the ATM gene, an essential guardian of genome stability, would show a higher prevalence of chromothripsis due to the associated defect in DNA double-strand break repair. Using whole-genome sequencing, fluorescence in situ hybridization and RNA sequencing, we characterized the genomic landscape of Acute Lymphoblastic Leukemia (ALL) arising in patients with Ataxia Telangiectasia. We detected a high frequency of chromothriptic events in these tumors, specifically on acrocentric chromosomes, as compared with tumors from individuals with other types of DNA repair syndromes (27 cases total, 10 with Ataxia Telangiectasia). Our data suggest that the genomic landscape of Ataxia Telangiectasia ALL is clearly distinct from that of sporadic ALL. Mechanistically, short telomeres and compromised DNA damage response in cells of Ataxia Telangiectasia patients may be linked with frequent chromothripsis. Furthermore, we show that ATM loss is associated with increased chromothripsis prevalence in additional tumor entities.

Intracranial hemorrhage in immune thrombocytopenia (ITP): fatal course in spite of maximum therapy.

We report the case of a 2-year-old boy with immune thrombocytopenia (ITP) who developed fatal intracranial hemorrhage (ICH) despite maximum therapy according to the guidelines. Hitherto defined risk factors do not predict severe or atypical courses.

Total body MRI-governed involved compartment irradiation combined with high-dose chemotherapy and stem cell rescue improves long-term survival in Ewing tumor patients with multiple primary bone metastases.

We examined the role of total body magnetic resonance imaging (TB-MRI)-governed involved compartment irradiation (ICI) and high-dose chemotherapy (HDC), followed by stem cell rescue (SCR) in patients with high-risk Ewing tumors (ETs) with multiple primary bone metastases (high-risk ET-MBM). Eleven patients with high-risk ET-MBM receiving initial assessment of involved bones by TB-MRI were registered from 1995 to 2000 (group A). In all, 6 patients out of 11 had additional lung disease at initial diagnosis; all had multifocal bone disease with more than three bones involved. After systemic induction with etoposide, vincristine, adriamycin (doxorubicin), ifosfamide, and actinomycin D (EVAIA) or VAIA chemotherapy, ICI of all sites positive by TB-MRI was administered, followed by HDC and SCR. A second group matched for observation period and consisting of 26 patients with more than three involved bones at diagnosis was treated with the European Intergroup Cooperative Ewing Sarcoma Study-92 (EICESS-92) protocol (group B). These patients did not receive TB-MRI and consequently did not receive TB-MRI-governed ICI, or HDC and SCR. Survival in group A vs group B was 45 vs 8% at 5 years and 27 vs 8% at 10 years after diagnosis (log rank and Breslow: P<0.005). We conclude that TB-MRI-governed ICI followed by HDC and SCR in ET-MBM is feasible and warrants further evaluation in prospective studies.

[Whole-body MRI in children with langerhans cell histiocytosis for the evaluation of the skeletal system]. / Ganzkörper-MRT bei Langerhans-Zell-Histiozytose im Kindes- und Jugendalter zur Beurteilung des Skelettsystems.

PURPOSE: The usefulness of whole-body MRI (WB-MRI) for the detection of skeletal lesions in patients with Langerhans cell histiocytosis should be documented on the basis of case presentations. MATERIALS AND METHODS: In six patients with histologically proven Langerhans cell histiocytosis, 14 WB-MRI examinations were performed to evaluate the skeletal system within disease staging (6 primary, 8 follow-up examinations). The examinations were performed on a 1.5 Tesla, 32-channel whole-body scanner. The examination protocol consisted of T 1-weighted and STIR sequences in coronal and sagittal orientation. For comparison, radiographs of the initial skeletal lesions and those that were additionally detected on WB-MRI were available. RESULTS: In 4 patients no additional skeletal lesions were found on WB-MRI besides the initial lesion leading to the diagnosis of unifocal single system disease. In 2 patients WB-MRI was able to identify additional skeletal lesions. In a 5 S year-old boy with the primary lesion located in the cervical spine, a second lesion was detected in the lumbar spine on the initial scan and in the skull and proximal femur during follow-up examination. In a 12 year-old girl with a primary lesion of the thoracic spine, WB-MRI diagnosed additional lesions in the pelvic bone and the tibia. In both patients the diagnosis of multifocal skeletal involvement led to chemotherapy. During follow-up examination, the healing response under therapy could be demonstrated. Comparison with conventional imaging showed that especially lesions located in the spine or the pelvis were not detectable on radiographs even when knowing the MR results. CONCLUSION: The extent of skeletal involvement in Langerhans cell histiocytosis has crucial impact on therapy and prognosis. Whole-body MRI has been reported to be an established method for the evaluation of disseminated skeletal disease with distinct advantages over conventional radiography and bone scintigraphy. Our results suggest that WB-MRI should also be the imaging modality of choice for the assessment of skeletal involvement in children with Langerhans cell histiocytosis.

[Using the gait laboratory for the investigation of orthopaedic clinical problems in children]. / Einsatz des Ganglabors bei klinisch-orthopädischen Fragestellungen in der Kinderorthopädie.

AIM OF THE STUDY: We point out multiple applications of a gait laboratory in solving different problems in the children's orthopaedic field. With typical examples we show how biometrical data of the gait laboratory can be helpful to solve problems in orthopaedic examinations. MATERIAL AND METHOD: The range of questions to be solved in the gait laboratory differs from individual diagnostic examinations of a patient up to the control of devices in the functional use at the patient. As a typical example for the individual examination we show the gait analysis in a 14-year-old girl with idiopathic chondrolysis of the hip joint. The functional use of orthopaedic devices will be shown in youths with neuroorthopaedic diseases. As a very special question to the gait lab we describe the supply of children and youths with optimal sport shoes for running. RESULTS: The biometrical measurement techniques generate exact data to solve individual diagnostic and therapeutic questions. Orthopaedic devices can be tested in their functional efficiency and quality. Special questions can be answered very flexible. CONCLUSION: Diagnosis and therapy in orthopaedics and children's orthopaedics rely on exact data. However, details of the dynamics during movement are neither visible to the most experienced orthopaedic surgeon nor can they be documented by conventional diagnostic imaging procedures. The present technical potential of biometric assessment methods allow to precise and correct some empirical knowledge, they open a wide field of new applications in diagnostic and therapeutic examinations.

Allelic imbalance at intragenic markers of Tbx18 is a hallmark of murine osteosarcoma.

We have recently identified a locus exhibiting a high frequency of allelic imbalance (AI) in both spontaneous human (HSA 6q14.1-15) and radiogenic murine (MMU9, 42 cM) osteosarcoma. Here we describe the fine mapping of the locus in osteosarcoma arising in (BALB/cxCBA) F(1) hybrid mice. These studies have allowed us to identify Tbx18, a member of the T-box transcriptional regulator gene family, as a candidate gene. Three intragenic Tbx18 polymorphisms were used to map the region of maximum AI to within the gene itself; 16 of 17 tumours exhibited imbalances of at least one of these markers. The highest frequency was found in exon 1, where 14 of 17 tumours were affected at a single nucleotide polymorphism at 541 nt. Two polymorphic CA repeat markers in intron 2 and intron 5 demonstrated overlapping regions of imbalance in several tumours. Both markers flanking the Tbx18 gene (D9Osm48 and D9Mit269) revealed significantly lower frequencies of imbalance and confirmed the limitation of the common interval to Tbx18. Examination of both the mouse and human annotated genomic sequences indicated Tbx18 to be the only gene within the interval. Sequence analysis of the Tbx18 coding region did not reveal any evidence of mutation. Given the haploinsufficiency phenotypes reported for other T-box genes, we speculate that AI may influence the function of Tbx18 during osteosarcomagenesis.

The genetics of radiation-induced osteosarcoma.

Individual genetic variation can influence susceptibility to the carcinogenic effects of many environmental carcinogens. In radiation-exposed populations those individuals with a greater genetically determined susceptibility would be at greater risk of developing cancer. To include this modification of risk into radiation protection schemes it is necessary to identify the genes responsible for determining individual sensitivity. Alpha-particle-induced osteosarcoma in the mouse has been adopted as a model of human radiation carcinogenesis, and genome-wide screens have been conducted for allelic imbalance and genetic linkage. These studies have revealed a series of genes involved in determining the sensitivity to radiogenic osteosarcoma formation.

[Expression of genes of potential importance in the response to chemotherapy in osteosarcoma patients]. / Expression von Genen mit möglicher prognostischer Bedeutung für das Ansprechen auf Chemotherapie bei Patienten mit Osteosarkom - Gene mit möglicher prognostischer Bedeutung beim Osteosarkom -

BACKGROUND: The prognosis of patients with osteosarcoma has considerably improved over the last 30 years, mainly due to developments in chemotherapy. However, almost half of the osteosarcomas do not respond to chemotherapy. Predictive markers for chemosensitivity at diagnosis are desirable. PATIENTS AND METHODS: In order to investigate the potential of some chemotherapy-associated genes with respect to their predictive value for chemosensitivity, the mRNA expression of 8 genes was evaluated in the osteosarcomas of 45 patients and correlated to the histological response to neoadiuvant chemotherapy. RESULTS: ERCC4, a member of the nucleotide excision repair system, showed a orrelation between expression and the histologically evaluated response to chemotherapy. The expression of the other investigated genes HER-2/neu, HSP 70, GST, DHFR, BCRP, ERCC1 and Mlh1 showed no significant correlation to response to chemotherapy. CONCLUSION: In our retrospective analyses, low expression of ERCC4 was shown to be related to poor response to chemotherapy. The potential value of ERCC4 as response predictor has to be investigated in a prospective study.

p53 Mutations in nasal natural killer/T-cell lymphoma from Mexico: association with large cell morphology and advanced disease.

Nasal NK/T-cell lymphoma is a unique form of lymphoma highly associated with Epstein-Barr virus, and with a characteristic geographic distribution. Recently, we showed that p53 is overexpressed in a high percentage of nasal NK/T-cell lymphomas. The aim of this study was to analyze the status of the p53 gene, and correlate it with the expression of p53 protein and its downstream target, the cyclin-dependent kinase inhibitor p21, in a series of 25 cases of well-characterized nasal NK/T-cell lymphoma from Mexico. The highly conserved exons 5 to 8 of the p53 gene were amplified by polymerase chain reaction and screened for mutations by denaturing high-pressure liquid chromatography. Abnormal polymerase chain reaction products detected by denaturing high-pressure liquid chromatography and additional selected cases were sequenced. In addition, the incidence of loss of heterozygosity at the p53 locus was analyzed in 12 cases. Of the 25 patients, 17 were male and 8 female (M:F ratio, 2.1:1), with a median age of 43 years (range, 21 to 93 years). Morphologically, most of the cases were composed of a mixture of medium-sized cells and large transformed cells (21 cases), and four cases were composed exclusively of large transformed cells. Three different groups determined by p53 gene status and expression of p53 protein were identified: group 1 was p53 +/p53 mutated (five cases, all with p53 missense mutations). Morphologically, three of the five cases were composed of large cells. All five cases revealed overexpression of p53 in the majority of the tumor cells with a mean of 86%. Unexpectedly, three of these cases also showed overexpression of p21. Four of the five patients presented with clinical stage IVB and died with disease. Group 2 was p53+/p53 wild-type (10 cases). Histologically, nine cases were of the mixed type, and one of the large cell type. The percentage of p53 overexpressing cells was lower than in the previous group with a mean of 23%. p21 was positive in 7 of the 10 cases. Six patients in this group presented with clinical stages I to II and four patients with advanced disease (stage III and IV). Five patients are alive 12 to 120 months later (mean, 24 months), three with no evidence of disease. Group 3 was p53-/p53 wild-type (10 cases). All cases showed mixed cell morphology. p21 was positive in 5 of 10 cases. Four patients presented with clinical stage I to II and six patients with advanced disease. Four patients are alive with no evidence of disease 9 to 60 months later (mean, 10 months). Overall, p53 mutations were present in 24% (5 of 21) of the evaluable cases, all of them overexpressing p53 in the majority of tumor cells. Cases with p53 mutations were associated with large cell morphology (P = 0.0162) and presented more often with advanced stage disease. Loss of heterozygosity at chromosome 17p was found only in 2 of the 12 (17%) cases investigated, both cases showed p53 mutations of the remaining allele. P21 overexpression (60% of cases) is frequent in nasal NK/T-cell lymphoma and seems to be independent of p53 gene status. The overexpression of p53 and p21, independent of p53 mutations, although as yet not clear, might be the result of Epstein-Barr virus infection, and warrants further investigation.

The effects of gestation on circulating progenitor cells.

The frequency of BFU-E in second-trimester fetal blood (484 +/- 104/10(5)) falls progressively during gestation to a value of 69 +/- 41/10(5) in cord bloods of 36 weeks gestation and beyond, but this is still significantly greater than adult blood values of 14 +/- 8 (P < 0.01). BFU-E obtained from unfractionated peripheral blood mononuclear cells from fetuses/neonates less than 36 weeks gestation were more sensitive to erythropoietin than adult BFU-E, but the sensitivity of highly purified BFU-E obtained from second-trimester fetal liver was similar to that in adult cells. Almost maximal growth of BFU-E from purified fetal progenitor cells could be achieved with erythropoietin alone, whereas adult cells required the presence of other factors with 'burst-promoting activity'.

[Acute intravasal hemolysis in Clostridium perfringens sepsis. Differential diagnosis of hemolytic episodes]. / Akute intravasale Hämolyse bei Clostridium-perfringens-Sepsis. Differentialdiagnose des hämolytischen Transfusionszwischenfalls.

A 19-year-old man with acute lymphoblastic leukaemia developed fever, general deterioration and somnolence 3 days after a cycle of cytostatic treatment. He had anaemia (haemoglobin 6.6 g/dl), leukopenia (100/microliters) and thrombocytopenia (7,000/microliters). As an acute septicaemia was suspected he received broad spectrum antibiotic therapy, together with two units of red cell and platelet concentrates. However, his condition worsened rapidly over the next 5 hours (meningism, seizures, fever to 41.1 degrees C, dyspnoea). Another blood count revealed severe haemolysis. Computed tomography of the skull demonstrated multilocular intraparenchymal gas formation. Although the antibiotic treatment was extended the patient died several hours later. Retrospective examination for suspected transfusion mismatch provided no evidence for erythrocyte incompatibility. But there was liberation of T-antigen as sign of a bacterial cause of erythrocyte damage. An anaerobic blood culture grew Clostridium perfringens. This case demonstrates that acute intravascular haemolysis in septicaemia should be considered in the differential diagnosis of transfusion mismatch.

[Massive and multi-transfusions in polytraumatized patients: long-term serologic markers of hepatitis B, hepatitis C and AIDS]. / Massiv- und Multitransfusion bei polytraumatisierten Patienten: Langfristige serologische Befunde zu Hepatitis B, Hepatitis C und AIDS.

302 out of 712 (42%) consecutive polytraumatized ICU patients received ten or more units of stored blood during primary and/or intensive care (1982 to 1987) treatment. 120 of the 197 surviving patients with an average number of transfusions of 23 (10 to 89) units were followed up after a mean interval of 70 (20 to 104) months. Mean duration of continuous post-ICU hospital stay was 17 (2 to 160) weeks, mean number of additional operative procedures was three (0 to 23). Manifest hepatitis had not occurred, all samples were negative for HIV testing. In nine samples (7.5%), anti-HBc-antibodies were positive, while HBs-antigen was negative. Ten patients (8.3%) tested positive for anti-HCV-antibodies (one combined with positive anti-HBc). The rate of serologically positive samples increased with the number of blood units given, duration of overall hospital stay and/or number of secondary surgery; all these findings failed to prove statistically significant. The rate of seropositivity for anti-HBc-antibodies corresponded well with the rate found in voluntary donors in FRG. Manifest or chronic hepatitis B was not observed. As to hepatitis C, the incidence of seropositivity for anti-HCV was found tenfold higher than in healthy blood donors in FRG. The relevance of this result remains unclear, but might indicate chronic post-transfusional hepatitis with high risk of cirrhosis. Among the patients testing positive for anti-HCV, too, acute manifest hepatitis had not occurred. Recently developed RIBA kits might improve specificity and sensitivity of anti-HCV testing. Thus, the frequency of PTH-C could decrease considerably.