Predictors of pulmonary metastases on chest computed tomography in children and adolescents with osteosarcoma-tips for qualifying patients for thoracotomy.

BACKGROUND: Osteosarcoma is the most common primary malignant bone tumour in children and adolescents. Lungs are the most frequent and often the only site of metastatic disease. The presence of pulmonary metastases is a significant unfavourable prognostic factor. Thoracotomy is strongly recommended in these patients, while computed tomography (CT) remains the gold imaging standard. The purpose of our study was to create tools for the CT-based qualification for thoracotomy in osteosarcoma patients in order to reduce the rate of useless thoracotomies. METHODS: Sixty-four osteosarcoma paediatric patients suspected of lung metastases on CT and their first-time thoracotomies (n = 100) were included in this retrospective analysis. All CT scans were analysed using a compartmental evaluation method based on the number and size of nodules. Calcification and location of lung lesions were also analysed. Inter-observer reliability between two experienced radiologists was assessed. The CT findings were then correlated with the histopathological results of thoracotomies. Various multivariate predictive models (logistic regression, classification tree and random forest) were built and predictors of lung metastases were identified. RESULTS: All applied models proved that calcified nodules on the preoperative CT scan best predict the presence of pulmonary metastases. The rating of the operated lung on the preoperative CT scan, dependent on the number and size of nodules, and the total number of nodules on this scan were also found to be important predictors. All three models achieved a relatively high sensitivity (72-92%), positive predictive value (81-90%) and accuracy (74-79%). The positive predictive value of each model was higher than of the qualification for thoracotomy performed at the time of treatment. Inter-observer reliability was at least substantial for qualitative variables and excellent for quantitative variables. CONCLUSIONS: The multivariate models built and tested in our study may be useful in the qualification of osteosarcoma patients for metastasectomy through thoracotomy and may contribute to reducing the rate of unnecessary invasive procedures in the future.

Cancer Stem Cell Markers in Rhabdomyosarcoma in Children.

(1) Background: The aim of the present study was to assess the cancer stem cell (CSC) markers CD24, CD44, CD133, and ALDH1A1 in rhabdomyosarcoma (RMS) in children and to define their prognostic role in this group of patients. (2) Methods: The study material was archival tissue specimens collected from 49 patients under 18 years of age and who had been diagnosed with RMS. Immunohistochemistry (IHC) was used to evaluate the expression of the selected CSC markers in the tumor tissue. Expression was evaluated using a semiquantitative IRS scale based on the one developed by Remmele and Stenger and was correlated with the clinical and pathomorphological parameters of prognostic importance in RMS. (3) Results: Expression of the selected CSC markers CD24, CD44, CD133, and ALDH1A1 was demonstrated in 83.7%, 55.1%, 81.6%, and 100% of the RMS patients, respectively. The expression of all of the assessed CSC markers was statistically significantly higher in the study group versus the control group. No significant correlation was found between the expression of the selected CSC markers and clinical and pathological prognostic factors that were analyzed. The expression of the CSC markers did not have a significant influence on RMS survival rates. (4) Conclusions: The results of the conducted study confirm the expression of selected CSC markers in rhabdomyosarcoma tissue in children. The study did not support the prognostic relevance of the expression of any of the assessed CSC markers. However, further studies are needed to fully understand the relevance of the selected CSC markers in RMS carcinogenesis.

Oxidative and Antioxidative Status Expressed as OSI Index and GSH/GSSG Ratio in Children with Bone Tumors after Anticancer Therapy Completion.

Aims. There are no data on the redox status of children with bone tumors in complete disease remission. Therefore, the presented study examined the reduced/oxidized glutathione (GSH/GSSG) ratio, total oxidant capacity (TOC) and total antioxidant capacity (TAC) values as well as the oxidative stress index (OSI) for assessing alterations in the oxidant/antioxidant balance in 35 children with osteosarcoma or Ewing's sarcoma after anticancer therapy completion (median 14 months) compared with a control group. Methods. GSH, GSSG, TOC, TAC concentrations and bone alkaline phosphatase (BALP) activity were evaluated by immunoenzymatic (ELISA) and enzymatic methods. Results. We found no differences in serum BALP activity between all survivors with bone tumors and the control group. Patients with osteosarcoma after anticancer therapy completion had significantly higher values of TAC, GSH and the GSH/GSSG ratio as well as GSSG than healthy subjects. In patients with Ewing's sarcoma, we found significantly higher values of TOC concentration compared with healthy children. In addition, survivors with Ewing's sarcoma had higher TOC concentrations and OSI index values (p < 0.01), but a lower GSH/GSSG ratio (p < 0.05) than survivors with osteosarcoma. A positive correlation between TOC and the post-therapy period was observed in survivors. Conclusions. We found that in survivors with bone tumors, a disturbed balance between prooxidants and antioxidants persists after the completion of anticancer treatment. Moreover, an increased TOC value together with the post-therapy period may suggest increasing oxidative processes in survivors with bone tumors after treatment. Further observations will allow assessment of the relationship between the oxidant/antioxidant status and the predisposition of survivors to bone neoplastic disease recurrence.

Application of array comparative genomic hybridization (aCGH) for identification of chromosomal aberrations in the recurrent pregnancy loss.

Spontaneous abortion occurs in 8-20% of recognized pregnancies and usually takes place in the first trimester (7-11 weeks). There are many causes of pregnancy loss, but the most important (about 75%) is the presence of chromosomal aberrations. We present the results of oligonucleotide array application in a cohort of 62 miscarriage cases. The inclusion criteria for the study were the loss after 8th week of pregnancy and the appearance of recurrent miscarriages. DNA was extracted from trophoblast or fetal skin fibroblasts. In the 62 tested materials from recurrent miscarriages, the detection rate was 56.5% (35/62). The most commonly found were aneuploidies (65%) (chromosomal trisomy 14, 16, 18, 21, and 22), Turner syndrome, and triploidy (17.1%). Other chromosomal abnormalities included pathogenic and likely pathogenic structural aberrations: 1) pathogenic: deletion 7p22.3p12.3 and duplication 9p24.3p13.2 inherited from the normal father, deletion 3q13.31q22.2 and deletion 3q22.3q23 of unknown inheritance and duplication of 17p12 inherited from father with foot malformation; 2) likely pathogenic variants: deletion 17p13.1 inherited from normal mother, deletion 5q14.3 of unknown inheritance and de novo deletion 1q21.1q21.2. Among these aberrations, six CNVs (copy number variants) were responsible for the miscarriage: deletion 7p22.3p12.3 and duplication 9p24.3p13.2, deletion 3q13.31q22.2 and deletion 3q22.3q23, and deletion 17p13.1 and deletion 1q21.1q21.2. Other two findings were classified as incidental findings (deletion 5q14.3 and 17p12 duplication). Our research shows that 17% of the aberrations (6/35 abnormal results) that cannot be identified by the routine kariotype analysis are structural aberrations containing genes important for fetal development, the mutations of which may cause spontaneous abortion.

Gorham-Stout disease involving ipsilateral clavicle and scapula in a child - a case report focusing on imaging and histopathological features of this extremely rare condition.

Gorham-Stout disease (GSD) is a very rare entity of unknown etiology, characterized by excessive intra-osseous proliferation of blood or lymphatic vessels, resulting in progressive resorption of bone matrix and destruction of bone. To date we have found only seven published cases concerning fully confirmed GSD of the shoulder girdle bones in children. Our case concerns an 8-year-old boy with involvement of the left clavicle and scapula. The knowledge of imaging and histopathological features is crucial for establishing the diagnosis of GSD, therefore the exchange of experiences in this field is essential for improving the care of affected patients.

Endoglin Expression and Microvessel Density as Prognostic Factors in Pediatric Rhabdomyosarcoma.

(1) Background: The study proposed to analyze microvessel density (MVD) in rhabdomyosarcoma (RMS) based on the expression of angiogenesis markers and define its prognostic role in this group of patients. (2) Methods: The study included forty-nine pediatric patients diagnosed with RMS. Tumor tissue expression of CD31, CD34, and CD105 was analyzed. MVD was calculated and correlated with clinical RMS prognostic parameters. (3) Results: CD31, CD34, and CD105 are expressed in all RMS cases. MVD/CD105 was significantly higher in the RMS group than in the control group. The mean and median values of MVD/CD105 in RMS were lower than MVD/CD31 and MVD/CD34. MVD/CD105 was significantly higher in patients with alveolar RMS and those with metastatic disease. Patients with higher levels of MVD/CD105 had a higher risk of death (HR = 1.009). (4) Conclusion: CD105 is a relevant angiogenesis marker in pediatric RMS, and MVD/CD105 is an independent risk factor of short overall survival in children with RMS.

Tumor expression of survivin, p53, cyclin D1, osteopontin and fibronectin in predicting the response to neo-adjuvant chemotherapy in children with advanced malignant peripheral nerve sheath tumor.

PURPOSE: Selected cell-cycle regulators and extracellular matrix proteins were found to play roles in malignant peripheral nerve sheath tumor (MPNST) biology. We aimed to analyze whether initial tumor tissue expressions of survivin, p53, cyclin D1, osteopontin (OPN) and fibronectin (FN) correlate with the response to neo-adjuvant CHT (naCHT) in children with advanced inoperable MPNST. METHODS: The study included 26 children with MPNST (M/F 14/12, median age 130 months) treated in Polish centers of pediatric oncology between 1992 and 2013. Tissue expression of markers was studied immunohistochemically in the manually performed tissue microarrays and assessed semi-quantitatively as low and high, based on the rate of positive cells and staining intensity. RESULTS: Good response to naCHT was noted in 47.6%, while poor-in 52.4% of patients. The response to naCHT was influenced negatively by the presence of neurofibromatosis NF1 and high initial tumor tissue expression of OPN, survivin, p53 and cyclin D1. Patients with high tumor expression of either OPN, survivin or p53 and those with simultaneous high expression of ≥ 3 of the markers, responded significantly worse to naCHT, than patients, in whom expression of ≤ 2 markers were detected at diagnosis. Nearly, 85% of patients expressing ≥ 3 markers, responded poor to CHT; while 87.5% of children, expressing ≤ 2 markers, were good responders. CONCLUSION: The initial tumor tissue expression of OPN, survivin, p53 and cyclin D1 may serve as markers to predict response to naCHT in pediatric advanced MPNST. Future studies in more numerous group of patients are needed to confirm these preliminary results.

The clinical significance of changes in ezrin expression in osteosarcoma of children and young adults.

Ezrin is a protein that functions as a cross-linker between actin cytoskeleton and plasma membrane. Its clinical role in osteosarcoma is unclear. The aim of this study was to investigate, in osteosarcoma, the prognostic value of ezrin expression at biopsy and changes in expression levels after preoperative chemotherapy. Thirty-eight newly diagnosed osteosarcoma patients aged 6-23 years were included. At diagnosis, 20 patients had localized disease, the others had distant metastases. Median follow-up was 75 months (range 13-135). Ezrin expression was assessed immunohistochemically in biopsy tissue and primary tumour specimens resected after chemotherapy. The influence on survival of changes in ezrin expression after chemotherapy was analysed. Ezrin expression was significantly higher after preoperative chemotherapy and changes compared to biopsy tissue were significantly lower in patients with early progression than in patients with relapse or no further evidence of disease (p = 0.006 and p = 0.002, respectively). Similarly, ezrin expression was higher after preoperative chemotherapy and exhibited less change in expression in deceased patients compared to patients surviving more than 5 years (both p = 0.001). Ezrin expression at biopsy was significantly associated with both histopathological aggressiveness (p < 0.001) and tumour size (p = 0.037). The results of this study provide evidence that changes in overexpression of ezrin due to preoperative chemotherapy could be a useful predictive and prognostic marker in patients with osteosarcoma.

Holoprosencephaly with agenesia of the prosencephalic ventricle.

Malformations of the forebrain are characterized by abnormalities in size, shape, and arrangement of the cerebral hemispheres and ventricles. We present the morphological picture of a brain with failure of the forebrain complementary to holoprosencephaly coexisting with absence of the anterodorsal part of the prosencephalic ventricles. The anomaly can be graded within the holoprosencephalic spectrum due to the main morphological features. However, such alterations as aplasia of the forebrain ventricles and prominent leptomeningeal gliomesodermal proliferation are related to atelencephaly. The observations confirm the common pathogenic mechanism of aprosencephaly/atelencephaly and holoprosencephaly. The malformation corresponds to a wide continuous spectrum with no clear-cut boundaries of abnormal formation of the prosencephalon.

[Assessment of anthropometric parameters and serum leptin and fetuin-A levels in children and adolescents with osteosarcoma after anticancer treatment]. / Ocena parametrów antropometrycznych oraz stezen leptyny i fetuiny-A u dzieci i mlodziezy po zakonczeniu leczenia miesaka kosciopochodnego.

UNLABELLED: Cancer and the use of a comprehensive anti-cancer treatment are unfavorable factors, which have a significant impact on bone mass accumulation, bone mineralization and consequently the occurrence of osteoporosis. Bone turnover is regulated by complex mechanisms, among which an important role play OPG/RANK/RANKL signaling pathway, adipokines, and fetuin-A. The aim of the study was to evaluate bone mineral density and concentrations of leptin and fetuin-A in patients with osteosarcoma after anti-cancer treatment. MATERIALS AND METHODS: The study included 50 children and adolescents aged 10-21 years. The study group consisted of 25 patients with osteosarcoma and 25 healthy counterparts as a control group. The examination was conducted 2 months after the last course of postoperative chemotherapy and included densitometric measurements: bone mineral content (BMC), bone mineral density (BMD), fat mass, lean mass and biochemical measurements: serum concentrations of calcium, magnesium, phosphate, 25-hydroksyvitamin D, alkaline phosphatase, leptin and fetuin-A. Concentrations of leptin and fetuin-A were determined by immunoenzymatic methods. RESULTS: In patients with osteosarcoma after anti-cancer treatment, we observed significantly reduced bone mineral content, bone mineral density and lean body mass compared with the healthy children (p < 0.05, p < 0.01, p < 0.05, respectively). Mean values of z-score of the whole body BMD and z-score of the lumbar BMD L1-L4 were significantly lower in patients than in the controls (p < 0.001). The serum concentrations of phosphate, magnesium, and alkaline phosphatase in both studied groups were similar, while calcium was significantly lower (p < 0.05) in patients than in the healthy children. The concentration of 25-hydroxyvitamin D was about two-fold lower, while leptin approximately 2.5-fold higher in patients than in the controls. The mean value of fetuin-A was similar in both studied groups. Statistically significant positive correlations between body composition parameters and the values of BMD, as well as between anthropometric parameters and leptin and fetuin-A were observed. CONCLUSION: The deficit in bone mass observed in patients with malignant bone tumors after anti-cancer treatment might be the result of decreased serum calcium and vitamin D concentrations. The observed correlation between anthropometric and biochemical parameters may indicate the link between bone and adipose tissue metabolism.

Neurocutaneous melanosis in children with giant congenital melanocytic nevi.

Twenty-four children with giant congenital melanocytic nevi underwent brain MRI at 1.5 T scanner. Melanin deposits in the brain were found in seven children (29.2%) located in temporal lobes, thalamus, cerebellum, and pons. One patient showed leptomeningeal involvement. Six patients were asymptomatic, and one had epilepsy. As opposed to previous reports, localization of skin nevi on anterior part of trunk was correlated to central nervous system involvement. In all patients with brain involvement skin nevi showed picture of compound nevus with neurofibromatic component.

Congenital glioblastoma coexisting with vascular developmental anomaly.

Congenital central nervous tumours form a unique group of neoplasms. They are different from other tumour groups not only due to the onset time but also to their histopathology, anatomic location, and biologic behaviour. Congenital glioblastoma is one of the rarest types of congenital brain tumours and is uncommon in the prenatal period. We report a rare case of congenital glioblastoma detected prenatally by ultrasound examination and magnetic resonance imaging at 26 gestational weeks. Based on MRI findings and consultation of a team of specialists, pregnancy was terminated at 28 weeks. The newborn presented hydrops foetal. The child died shortly after birth due to cardiorespiratory insufficiency. At autopsy a large tumour with a spongy-like appearance was found. The tumour involved nearly the whole right cerebral hemisphere and led to marked hydrocephalus. In the histological and immunohistochemical examination, the tumour presented features of glioblastoma. Neoplastic cells were immunopositive for GFAP, S-100 protein and negative for neuronal markers. Frequent mitoses and high MIB-1 labelling index were seen in the tumour areas. The coexistence of tumour and vascular developmental anomaly was stated. The conglomerates of numerous, distended, thin-walled foetal-like blood vessels were located beside the tumour tissue, which presented disturbance in differentiation and maturation of the vascular net. Such coexistence of malignant glioma with vascular developmental anomaly is unique.

Miliary brain metastases from papillary adenocarcinoma of the lung - unusual MRI pattern with histopathologic correlation.

Miliary brain metastases are very rarely described in the literature but if they are, they are quite obvious on magnetic resonance imaging (MRI) and enhance after intravenous administration of the contrast medium. The authors presented a case of miliary metastatic spread to the brain which was invisible on computed tomography and hardly visible on MRI, i.e. as countless, tiny, slightly T1-hyperintense foci that did not enhance. The authors discussed a few T1-hyperintense brain lesions which did not include metastases (except for metastatic melanoma which was a radiological suggestion after brain MRI). Autopsy revealed papillary adenocarcinoma of the lung with numerous metastatic lesions in both cerebral and cerebellar hemispheres and the meninges.

A prognostic evaluation of vascular endothelial growth factor in children and young adults with osteosarcoma.

BACKGROUND: The potential role of VEGF in osteosarcoma has been evaluated in several studies. The majority of them included heterogeneous and limited series of patients, giving conflicting results. The aim of presented study is to evaluate the prognostic role of VEGF-A in biopsy samples of clinically homogeneous group of osteosarcoma patients with at least 5 years of follow up. MATERIALS AND METHODS: VEGF-A was assessed immunohistochemically in the pre-treatment biopsy samples of 91 patients (mean age 14 years; range, 4-23 years) with primary, high-grade, non-metastatic osteosarcoma localized in extremities. The survival of each patient was assessed after at least 5-year follow-up period. RESULTS: VEGF-A over 50% of positive tumor cells was observed in 39% of cases and was linked to patients age below 14-year old (P = 0.025) and tumor size more than 8 cm (P = 0.054). VEGF-A was associated with a significantly decreased both overall survival (P = 0.006) and progression-free survival (P = 0.011). In the Cox proportional hazard model it was confirmed that VEGF-A expression in the biopsy samples was an independent prognostic factor of unfavorable survival in osteosarcoma (HR 2.51; 95% CI: 1.12-5.66). CONCLUSION: The expression of VEGF-A in the biopsy sample is the potential marker for predicting the course and outcome of osteosarcoma.

Expression and significance of HER family receptors in neuroblastic tumors.

HER receptor family plays an important role in normal embryonic development and is involved in pathogenesis and progression of some types of cancer. Neuroblastic tumors (NT) are common pediatric neoplasms with a poor outcome in a significant number of patients. The biological and prognostic role of HER family in NT is not well established. In the current study we evaluated HER1-4 receptors expression, their prognostic significance and clinicopathological correlations in a series of 103 NTs by immunohistochemical assessment of HER1-4 expression and FISH analysis of EGFR and HER2 copy number status. HER receptors are commonly expressed in NT but it was not due to EGFR or HER2 amplification. EGFR, HER2 and HER4 show correlation with tumor histology. It seems that these receptors take part in neuroblastic cell differentiation and Schwannian stroma development. EGFR and HER2 positivity are more frequently found in favorable histological risk group of tumours (P = 0.004 and P = 0.01 respectively) while high expression of HER4 is significantly more often found in patients with metastatic disease (P = 0.03). Moreover tumors with HER2 polysomy were more often found in children ≤ 18 months, with localized disease, and favorable histological group. Our study showed that the role of HER family members in NT biology is interrelated and complex but their expression level may present a novel prognostic factor for NT patients outcome.

[A comparison of serum concentrations of biochemical bone turnover markers in patients with osteosarcoma with good and poor prognosis]. / Analiza stezenia biochemicznych markerów obrotu kostnego u chorych na miesaka kosciopochodnego z korzystnym i niekorzystnym rokowaniem.

UNLABELLED: Osteosarcoma is a primary malignant bone tumor, whose peak incidence occurs in the second decade of life during the adolescent growth spurt. Complex oncological treatment consisted of chemotherapy combined with surgery which substantially increased the cure rate of patients with osteosarcoma, but it is very important to identify patients with poor prognosis and to treat them with more aggressive therapy. THE AIM OF THIS STUDY: To assess serum biochemical bone turnover markers as prognostic indicators in patients with osteosarcoma. MATERIAL AND METHODS: We studied 55 patients from age 5 to 20 years with diagnosed osteosarcoma treated at the Institute of Mother and Child in Warsaw. The studied group was divided into 2 subgroups consisted of 27 patients with favorable (disease remission) and 28 patients with unfavorable (disease progression) prognosis. Venous blood was collected from patients in the morning hours at time of diagnosis, during anticancer treatment and after completion of treatment. Serum osteocalcin (OC), bone alkaline phosphatase (BALP) and C-terminal cross-linking telopeptide of type I collagen (CTX) were analyzed by immunoenzymatic methods. RESULTS: At time of diagnosis, in patients with unfavorable prognosis concentration of bone formation markers were higher (OC by 30% and BALP by 60%) than in those with good prognosis, however, CTX level was similar in both groups of patients. During chemotherapy in patients with poor prognosis we observed higher levels of bone turnover markers in comparison to subjects with favorable prognosis. After the completion of therapy, in patients with progression median values of bone formation markers were over twofold and bone resorption marker about 50% higher as compared to patients with remission of disease. These differences were statistically significant at p < 0.05 for OC, p < 0.001 for BALP and p < 0.01 for CTX. CONCLUSIONS: Our results suggest that bone turnover markers, especially bone alkaline phosphatise may be useful in the monitoring and in the assessment of the efficacy of therapy in children with osteosarcoma. Higher rates of bone formation and resorption during treatment and after its completion are associated with unfavorable prognosis and may indicate progression of disease.

Prognostic significance of HER2 expression in neuroblastic tumors.

HER2 is essential for normal embryonic development and has a critical function in oncogenesis and progression of some types of cancer. Neuroblastic tumors create a heterogenous group of pediatric embryonal tumors of sympathoadrenal lineage. The biological and prognostic function of HER2 in these tumors is not well established. In this study, we evaluated the status of HER2, its prognostic significance, and clinicopathological correlations in series of 79 untreated neuroblastoma. The immunohistochemical assessment of HER2 and Ki-67 (proliferation index) as well as HER2 copy number status were performed on tissue microarrays. HER2 expression characterized 63 tumors, including 34 with low and 29 with high level, showing either membranous or mixed membranous-cytoplasmic pattern. Sixteen cases were HER2 immunonegative. The pattern of immunolabeling depended on the maturity of neuroblastic cells, being the most intense in differentiating neuroblasts. None of the tumors revealed HER2 amplification. In the examined group, 20% of patients died of disease from 4 to 107 months (median 18) from the diagnosis, and the survivors were followed up for 14-149 months (median 59). Patients' age, stage of disease, tumor location, mitosis/karyorrhexis index (MKI), and presence of HER2 expression were statistically significantly related to survival probability as detected by the Cox proportional hazard model. In the univariate analysis, Kaplan-Meier curves revealed significantly poorer outcome of HER2 negative than HER2-positive tumors (either low or high expression). The immunonegativity was associated with adverse clinicopathological parameters, including poor survival, metastatic stage of disease, un- or poorly differentiated histology, high MKI, and higher proliferation index. In conclusion, HER2 expression, not accompanied by gene amplification, is common in neuroblastic tumors. HER2 positivity seems to have a positive prognostic significance. HER2 expression with a variable pattern is a marker of the stage of neuroblastic cells differentiation.

EGFR, PIK3CA and PTEN gene status and their protein product expression in neuroblastic tumours.

PI3K/AKT/mTOR pathway signalling is often upregulated in cancer, usually by the constitutional activation of growth factor receptors, amplification or mutation of PIK3CA and loss of tumour suppressor PTEN function. The way of PI3K/AKT/mTOR pathway activation in neuroblastoma (NB) is not well established. The study was performed on paraffin-embedded tissue sections from 106 patients with NB. The aim of the study was to analyse the mutational status of EGFR (exons 18-21), PIK3CA (exons 5, 6, 10 and 21) and PTEN (all exons) genes, as well as to assess expression of their protein products by immunohistochemistry. A novel mutation in exon 5 of PIK3CA, c.931 A>G (p.I311V), in two infantile tumours (2.7%) was identified. In addition some polymorphisms were found in all examined genes, including a novel one, c.285 A>T in PTEN. Polymorphism PIK3CA c.1060-17 C>A was significantly more frequent in extra-adrenal tumours. Polymorphism PIK3CA c.1145+54 A>G showed a tendency to be more frequent in children older than 18 months and in extra-adrenal tumours. Expression of EGFR was present in 95% of cases, PI3Kp110 in 92% of tumours and PTEN in all tumours (low in 39%) and did not correlate with the genetic alterations. EGFR and PTEN expression showed an association with tumour differentiation. Mutations in the EGFR, PIK3CA and PTEN genes are infrequent in neuroblastoma. Both newly detected mutations in exon 5 of PIK3CA occurred in very low risk neuroblastic tumours in infants. EGFR, PI3Kp110 and PTEN expression is a common feature of NB.

[Biochemical bone turnover markers in patients with conventional and nonconventional osteosarcoma]. / Markery obrotu kostnego u chorych na konwencjonalna i niekonwencjonalna postac histologicznq miesaka kosciopochodnego.

UNLABELLED: Biochemical bone turnover markers which reflect bone formation as well as bone resorption processes are sensitive indicators of early bone metabolism disturbances. They are considered to be useful in diagnosis and treatment of many metastatic bone diseases and primary osseous tumours. THE AIM: of the study was to assess bone turnover markers in patients with conventional and nonconventional osteosarcoma during treatment. MATERIAL AND METHODS: We examined 55 patients (5-20 years) with osteosarcoma. Among them 91% had conventional and 9% had nonconventional histology. Among patients with most frequent conventional osteosarcoma distinguished histological subtypes. Bone turnover markers were determined in serum by immunoenzymatic assay at diagnosis, during preoperative- and postoperative chemotherapy and then after treatment. RESULTS: We found different values of bone turnover markers in serum of patients with conventional osteosarcoma. At the moment of biopsy the highest value of osteocalcin in patients with fibroblastic subtype was observed. The highest activity of bone alkaline phosphatase and collagen type I crosslinked C-telopeptide in children with osteoblastic subtype of osteosarcoma were obtained. The levels of tested parameters decreased about 20-40% during preoperative and postoperative chemotherapy, then they increased after treatment first of all in patients with chondroblastic subtype (p < 0.05). Next we found that the osteocalcin concentration was 4-fold lower, in nonconventional osteosarcoma in comparison to the conventional. This marker is stable during treatment and remains unchanged after it. Moreover we showed that the changes of the bone alkaline phosphatase activity and the collagen type I crosslinked C-telopeptide concentration during and after treatment were less dynamic in children with nonconventional osteosarcoma. CONCLUSIONS: Observed changes of markers in various histological subtypes of osteosarcoma can indicate different rate of their bone turnover. Changes observed during treatment are more dynamic in conventional than in nonconventional type of osteosarcoma.

Rare pancreatic tumour in a 16-year-old girl: a case report.

A 16-year-old girl was admitted to a hospital after having noticed clearly palpable abdominal mass, without accompanying symptoms. At surgery a tumour superficially attached to the pancreatic tail, well-encapsulated, measuring approx. 8x5x3 cm, had been found and resected. Histological examination using routine hematoxylin and eosin staining, additional histochemical and immunohistochemical techniques revealed low-grade tumour with mixed appearances of PSEN and pancreatoblastoma; both of these tumours originate from pancreatic primordia.