Insulin-like growth factor-1 receptor expression in pediatric tumors: a comparative immunohistochemical study

Background/aim: Insulin-like growth factor-1 receptor (IGF-1R) is a pivotal receptor tyrosine kinase involved in the cell cycle and malignant tumor transformation. It is differentially expressed in various types of tumors. We aimed to determine the expression of IGF- 1R in different pediatric tumors and to shed light on possible new indications of anti-IGF-1R treatment approaches. Materials and methods: A total of 147 specimens were analyzed according to their expression of IGF-1R. Specimens included those from rhabdomyosarcomas, Wilms tumors, Ewing sarcoma/primitive neuroectodermal tumors, peripheral neuroblastic tumors, acute lymphoblastic lymphoma, Hodgkin lymphoma, Burkitt lymphoma, retinoblastoma, pleuropulmonary blastoma, Langerhans cell histiocytosis, endodermal sinus tumors (ESTs), and myeloid sarcoma. Analysis was performed on tissue sections by immunohistochemically staining for IGF-1R expression. Results: All six specimens of EST cases showed positivity for IGF-R1. Additionally, about 56% of the Hodgkin lymphoma, 80% of the rhabdomyosarcoma, and 70% of the Wilms tumor specimens showed positivity for IGF-R1 expression. Conclusion: All ESTs examined in our study expressed IGF-1R and to our knowledge this is the first report regarding ESTs and IGF-1R expression. IGF-1R could be included among confirmatory markers for ESTs and, from a therapeutic viewpoint, ESTs should also be examined for IGF-1R expression for beneficial regimens.

Recurrence of childhood nephrogenic adenoma in urinary bladder developed four years after previous surgery despite intravesical sodium hyaluronate therapy.

Nephrogenic adenoma (NA) is a rarely seen benign metaplastic lesion of the urinary tract. Its etiology is uncertain, but induced by chronic inflammation, irritation, and trauma. NA is located in the urinary tract, most commonly in the bladder. NA usually presents with hematuria and lower urinary tract symptoms. In the literature it is mostly seen in adults but about 30 cases of NA's have been reported in children. Treatment of intravesical lesions consists of transurethral resection (TUR) and fulguration and rarely partial or total cystectomy may be required in ineffective TUR. Recurrence rate is high during long-term follow-up. The intravesical application of sodium hyaluronate produces a protective effect on the glycosaminoglycan layer and delays or prevents its recurrence. We report a case of recurrent NA of the bladder in a pediatric male patient who was presented four years after previous surgery despite intravesical sodium hyaluronate therapy.

Expression of Epstein-Barr virus in children with sacrococcygeal pilonidal sinus determined by immunohistochemical methods.

In this study, we probed whether chronic infections of skin such as pilonidal sinus could be a potential site of Epstein-Barr virus (EBV) replication. Pilonidal sinus is associated with a high recurrence rate. Therefore, we decided to determine the role of EBV's presence to explain whether it is correlated with the recurrence of pilonidal sinuses. This study was conducted on 36 patient samples with sacrococcygeal pilonidal sinus. Samples were immunohistochemically stained for EBV, CD3 and CD20 expression. Thirty-six adolescents with pilonidal disease were evaluated. EBV-positive cells were located in dermis with high inflammatory activity. EBV-positive cells stained positive for the B-cell antigen CD20 and were detected in 10 of 36 (27%) pilonidal sinus specimens. Among those who had experienced a relapse, three were positive for EBV expression. In addition, EBV expression was detected in eight cases with severe inflammation, and in two with minimal or moderate inflammation. Our study advances the field by demonstrating that similar to gastrointestinal mucosa, skin could be a reservoir for EBV. EBV was found to be restricted to B cells in skin lesions, and it was found that skin lesions with severe inflammation showed higher frequency of EBV expression in comparison to minimal or moderately inflammed skin lesions. Additionally, recurrence was more frequently observed among EBV-positive cases. These findings point out for a role of EBV infection in the recurrence of pilonidal sinuses.

Anaplastic lymphoma kinase gene expression in small round cell tumors of childhood--a comparative immunohistochemical study.

The focus of this study was to investigate anaplastic lymphoma kinase (ALK) expression by immunohistochemistry using a highly specific antibody. Distribution and frequency of ALK expression may provide a clue for ALK inhibitor use in small round cell tumors of childhood. The study group involved 76 small round cell tumors of childhood, which composed of 11 rhabdomyosarcomas, 13 Wilms tumors, 7 Ewing sarcoma/primitive neuroectodermal tumors, 34 peripheral neuroblastic tumors, and 11 acute lymphoblastic lymphoma. Anaplastic lymphoma kinase protein expression in small round cell tumors of childhood is poorly described in the literature. The findings of our study highlight a potential and possible role of targeting ALK in pediatric solid tumors by using ALK immunohistochemistry. Anaplastic lymphoma kinase may also have an oncogenic role in rhabdomyosarcomas and peripheral neuroblastic tumors, and they may possibly be treated with ALK inhibitors. Anaplastic lymphoma kinase expression in Wilms tumors is not reported in the literature, previously. Our study evaluated ALK expression in Wilms tumor samples.

Is there an association between histopathological changes in the lower ureter and renal functions? Evaluation of patients who underwent ureteroneocystostomy for ureterovesical obstruction or vesicoureteral reflux.

BACKGROUND/AIM: We aimed to assess the relationship between the histological changes of the ureterovesical junction (UVJ) and renal functions. Therefore, we evaluated histological changes of the lower ureter and renal scintigraphy findings of patients for whom ureteroneocystostomy was performed because of vesicoureteral reflux (VUR) or ureterovesical junction obstruction (UVO). MATERIALS AND METHODS: UVJ specimens were obtained from 18 children. We investigated the changes in neuronal innervation, muscular morphology, extracellular matrix, and apoptosis rate with renal scintigraphy findings. RESULTS: Seven UVO and 11 VUR patients were treated. Alpha-actin expression in smooth muscle cells was found to be lower (P < 0.001) while neuronal defect was more prominent in the UVO group (P = 0.002). The renal functions decreased as the smooth muscle structural defect increased in the VUR group (P < 0.05). CONCLUSION: Neuronal tissue and muscle tissue were more defective in the UVO group. The decrease in neuronal fibers and muscle cells explains the pathogenesis of the obstructive group, but no difference was observed regarding the accumulation of collagen type 3 and cellular apoptosis between the VUR and UVO groups. In the VUR group, renal functions decreased while the smooth muscle defect at the distal end of the ureter increased.

Paraganglioma presenting with marked proteinuria: a case report.

Paragangliomas are rare neuroendocrine tumors that arise from sympathetic and parasympathetic paraganglia. In children, most of them are functional tumors. Presenting symptoms such as sustained or paroxysmal elevations in blood pressure, headache, sweating, and palpitations are related to catecholamine hypersecretion. A previously healthy 8-year-old boy presented with marked proteinuria, hypertension, and heart murmur. Imaging revealed an 81×43×45 mm sized solid mass extending from right retroaortic area to left suprarenal region. Measurements of catecholamines suggested the diagnosis of paraganglioma. Pathologic examination confirmed the diagnosis. Complete tumor resection was performed. Proteinuria, hypertension, and cardiac signs resolved after surgery. Proteinuria has been described as a rare manifestation of paragangliomas in adult patients. This is the first case of a paraganglioma presenting with massive proteinuria in a child.

Osteopontin expressions correlate with WHO grades and predict recurrence in meningiomas.

Recurrence of meningiomas is a major prognostic issue. Although World Health Organization (WHO) histopathological grading correlates strongly with recurrence, it has some limitations, and predicting the biological behavior of grade I meningiomas is particularly difficult. Osteopontin (OPN) is a protein known to be involved in tumor progression. The purpose of this study is to determine expression of OPN in meningiomas and to investigate its correlation with WHO grades and tumor recurrence. Immunohistochemical (IHC) evaluation of expression of OPN was performed by two different methods to ensure reliability. OPN IHC and Allred scores were calculated on the basis of intensity and extent of staining. Both scores were in agreement and correlated significantly with meningioma grade and Ki-67 index. OPN scores were also significantly correlated with recurrence of WHO grade I meningiomas. Cut-off values for OPN IHC and OPN Allred scores between non-recurrent and recurrent grade I meningiomas were calculated as 70 and 5.5 respectively. We concluded that OPN is a valuable marker for grading meningiomas and for predicting the recurrence in WHO grade I tumors.

Spindle cell rhabdomyosarcoma displaying CD34 positivity: a potential diagnostic pitfall; report of two pediatric cases.

Spindle cell rhabdomyosarcoma is a rare subtype of rhabdomyosarcoma mainly seen in children. Occasional aberrant staining with a variety of immunohistochemical markers has been noted. The aberrantly expressed markers include alpha-smooth muscle actin, cytokeratin, S100, neurofilaments, CD20, immunoglobins, and CD117. We report herein two pediatric cases displaying strong CD34 positivity and one with additional focal CD117 positivity, causing considerable difficulty in distinction from solitary fibrous tumor and extra-gastrointestinal stromal tumor. To our knowledge, CD34 staining has been merely reported in rhabdomyosarcoma. Spindle cell rhabdomyosarcoma has to be considered in the differential diagnosis of childhood spindle cell tumors. Post-chemotherapy specimens should be evaluated in caution, since chemotherapy can cause considerable changes in tumor antigen expression. Since CD117 and CD34 are stem cell markers, their positivity in pediatric tumors should be interpreted with caution. Even if the morphology is not supportive, a wide immunohistochemical panel should be applied in childhood malignant solid tumors.

Solid tumors in Turkish children: a multicenter study.

BACKGROUND: This paper presents a detailed incidence study on childhood solid tumors comprising a histopathology-based documentation of benign and malignant lesions. METHODS: The Ankara Pediatric Pathology Working Group collected databases of pediatric solid tumors from six pediatric reference centers in order to analyze the incidence, distribution and some epidemiologic characteristics of the tumors and to establish a multicenter database for further studies. A five-year retrospective archive search was carried out. Excluding epithelial tumors of the skin, leukemia, lymphoreticular system neoplasias, metastatic tumors, and hamartomas, 1362 solid tumors in 1358 patients were classified according to age, sex, localization, histopathology and clinical behavior. RESULTS: The male/female ratio was 0.9; 14.8% (201) of the patients belonged to 0-1 year age group, 20.7% (281) to 2-4 years, 25.9% (352) to 5-10 years, 22.2% (301) to 11-14 years, and 16.4% (223) to 15-18 years. Among all tumors, 708 (52.0%) were malignant, 645 (47.4%) benign tumors, 2 (0.1%) borderline tumors, and 2 (0.1%) unknown behavioral tumors. Malignant tumors were found in 50.2% (357) of female patients and in 54.0% (349) of male patients. A balanced distribution between benign and malignant entities among children under 18 years was observed. Comparison between the age groups revealed malignant cases outnumbered benign cases under 4 years of age while benign tumor numbers increased after 10 years of age. The most common entities in the malignant group were of sympathetic nervous system origin, while soft tissue tumors far outnumbered the others in the benign group. CONCLUSIONS: We conclude that the cancer patterns of children in the Ankara region mostly resemble with those of the western population. This study provides useful information on the diagnosis of solid tumors in children and highlights variations in cancer incidence in different age groups.

Multiple axillary-infraclavicular lymph node metastasis from malignant rhabdoid tumor of unknown primary site.

Malignant rhabdoid tumors (MRT) mostly originate from the kidney and central nervous system. However, they may also originate from retroperitoneal and paravertebral regions, mediastinum, liver, chest wall, extremity, and neck, as well as from the soft tissues. The most important method in the differential diagnosis is the analysis of cytogenetic alterations in the INI1 gene. A six-month-old girl presented with multiple conglomerated lymphadenopathies located in the anterior axillary line. MRT diagnosis was confirmed by loss of INI1 expression in the tumor tissue. This is the first case in the literature with unknown primary focus diagnosed from lymph node metastasis.

Calretinin immunohistochemistry in Hirschsprung's disease: An adjunct to formalin-based diagnosis.

AIM: This study was designed to assess the utility of calretinin immunohistochemistry in the diagnosis of Hirschsprung's disease. MATERIAL AND METHODS: Eleven definitive resection materials from 10 Hirschsprung's disease patients and 3 initial full-thickness rectal biopsies of these patients were retrieved from the pathology archives. Additionally, 15 distal colon and 13 proximal colon full-thickness samples from 23 non-Hirschsprung's disease patients were also evaluated as the control group. All material was reevaluated by light microscopy for the presence or absence of ganglion cells and immunostained with calretinin, including proximal surgical margins and aganglionic zone samples from each resection material. RESULTS: Immunohistochemistry for calretinin provided highly compatible results with hematoxylin-eosin findings in Hirschsprung's disease and non-Hirschsprung's disease patients, except in one Hirschsprung's disease patient with very rare nerve stainings at the distal surgical margin. CONCLUSIONS: Calretinin immunohistochemistry was found to be highly sensitive and specific in detecting aganglionic segments. New research should be conducted in order to clarify calretinin staining patterns of the transitional zone, rare Hirschsprung's disease types, pure hypoganglionosis patients, and the anorectal junction, and for the mapping of fetal and neonatal colonic specimens. The technique seemed very effective for lowering the need for excessive sectioning and practical regarding the erratic nature of the acetylcholinesterase staining.

Ganglioneuroma in a child with hereditary spherocytosis.

Hereditary spherocytosis (HS) is the most frequent cause of congenital hemolytic anemia. Extramedullary hematopoiesis (EMH) mimicking a mass may develop in the lymph nodes, kidneys, pleura, mediastinum, adrenal gland, and in particular the spleen and liver. Other than EMH, B-cell lymphoma, acute lymphoblastic leukemia, and pancreatic schwannoma cases were reported in patients with HS. We present a 13-year-old female patient with HS and ganglioneuroma in the adrenal gland. This association is probably coincidental; however, with increasing cancer cases in HS and the genetic studies being made, this association will be clarified.

Childhood fibroblastic and myofibroblastic tumors: a multicenter documentation and review of the literature.

OBJECTIVE: In this study, we aimed to give a documentation of 37 cases of childhood fibroblastic/myofibroblastic tumors retrieved from the archives of 6 reference centers in Ankara along with a comprehensive review on the subject. MATERIAL AND METHOD: A retrospective archive search was carried out for the period between 2006-2010 in 6 reference centers in Ankara covering patients with ages ranging between 0-18 years. All the tumors categorized under fibroblastic and myofibroblastic group according to World Health Organization criteria were collected. RESULTS: The study comprised 407 soft tissue tumors in total. Fibroblastic/myofibroblastic tumors constituted 9,1 % (37 cases) of these tumors. According to histopathology; 16 cases were categorized as fibromatosis, 8 cases as inflammatory myofibroblastic tumor, 6 cases as infantile fibrous hamartoma, 3 cases as nodular fasciitis and 2 cases as infantile myofibroblastic tumor/myofibromatosis and 1 case as cranial fasciitis. The only malignant case was an infantile fibrosarcoma. CONCLUSION: Infantile fibrosarcoma was lower than reported series and a male predominance was noted. The low incidence of newly described entities as well suggests that these tumors may have been unrecognized.

CD117 and CD34 staining patterns in childhood benign mammary lesions.

OBJECTIVE: CD117 and CD34 are markers that have both been implied in cancer progression in adult breast lesions. This study was conducted in order to create a retrospective documentation and to analyze the expression patterns of these markers on childhood benign lesions along with a comparison with adult breast lesions' staining patterns. MATERIAL AND METHOD: Nine fibroadenomas, 2 tubular adenomas, 1 mammary hamartoma, 2 gynecomastias, 1 benign phyllodes tumor were retrieved from pathology archives of two reference centers between 2005-2010. RESULTS: CD117 staining was identified in the epithelium of all cases in fibroadenoma/tubular adenoma group and focally positive in 1 mammary hamartoma, 2 gynecomastias, and 1 benign phyllodes tumor. CD117 staining was detected in the stroma of 8 cases. Three fibroadenomas, 1 mammary hamartoma, 2 gynecomastias and 1 benign phyllodes tumor lacked stromal labelling for this marker. All cases were strongly and diffusely positive for CD34 except the benign phyllodes tumor case. This case presented marked loss of stromal CD34 staining when compared to the surrounding stroma. Additionally, pseudoangiomatous stromal hyperplasia was noted in 2 gynecomastias and in the peritumoral stroma of benign phyllodes tumor case. CONCLUSION: Our study demonstrated that fibroadenoma was the most commonly encountered breast lesion in childhood and that adolescent fibroadenomas showed similar staining patterns for CD117 and CD34 as for adult counterparts. On the other hand, different expression patterns of CD117 and CD34 between adenoma group and the gynecomastias and benign phyllodes tumor group may implicate different mechanisms of development and tumorigenesis among these groups.

Stromal expression of CD34, α-smooth muscle actin and CD26/DPPIV in squamous cell carcinoma of the skin: a comparative immunohistochemical study.

Invasion pathogenesis is one of the most complicated issues in the literature. There are numerous studies concerning the tumor markers implicated in the preinvasive-invasive tumor sequence. Despite ample studies on the invasion pathogenesis of cutaneous melanomas, there is limited and dispersed work presently available on non-melanoma skin cancer. The vast knowledge in the literature concerning this issue in squamous cell carcinoma comes mostly from the studies of the oral cavity, esophagus, larynx, and cervix. In this study, we investigated tumor-free neighboring stroma and tumor stroma in squamous cell carcinomas (SCCs) of the skin as well as keratoacanthomas (KAs) with respect to the presence of stromal CD34-positive (CD34+) fibrocytes and α-smooth muscle actin-positive (α-SMA+) myofibroblasts using seborrheic keratosis (SKs) and non-tumoral skin samples as controls. We also evaluated the stromal expression pattern of CD26/DPPIV (CD26), a tumor suppressor gene product that also has immunoregulatory properties. Immunohistochemistry was performed on samples of 31 SCC, 8 KA, 15 SK and 10 non-tumoral skin samples. Peri-tumoral stroma from resection margins was also evaluated. We found that CD34 and α-SMA demonstrated significantly different staining between benign and malignant squamous skin lesions consisting of a loss of CD34+ fibrocytes paralleled by a gain of α-SMA+ myofibroblasts in malignant tumor stroma. Additionally, it was shown that CD26 expression was lower in tumor stroma when compared to that of tumor neighboring stroma. However, we concluded that this finding may be attributable to the solar elastosis areas in the peritumoral tissue, which shows diffuse strong positivity for this marker.

Spinal Tuberculosis (Pott's disease) Mimicking Paravertebral Malignant Tumor in a Child Presenting with Spinal Cord Compression.

Paravertebral tumors may interfere with the radiological and clinical features of spinal tuberculosis. We report a case of a 3-year-old boy with spinal tuberculosis who was initially misdiagnosed as having a paraspinal tumor. The diagnosis of tuberculosis was made on the basis of intraoperative findings and confirmed by histopathology. This case highlights the importance of awareness of the different radiographic features of spinal tuberculosis, which can mimic a spinal malignancy. In order to avoid delayed diagnosis, pediatricians and radiologists must be aware of spinal tuberculosis, which may interfere with other clinical conditions.

Metanephric stromal tumor: a challenging diagnostic entity in children.

A case with a renal mass diagnosed as metanephric stromal tumor is presented. A 6-year-old boy presented with frequently recurring urinary tract infections. He had been followed up at different medical centers for the last 2 years with a 2 × 2 cm simple cyst localized in the inferior pole of the left kidney. At our center, ultrasonography revealed a heterogeneous mass in the left kidney with a central cystic component. The patient underwent operation for left renal mass, and heminephrectomy was performed. The 5 × 4 × 2.5 cm left heminephrectomy specimen showed a partially cystic mass composed of bland spindle cells distributed haphazardly, entrapping tubules and glomeruli and producing fine collarettes around some tubules. The cysts were lined with a 1-layered flat or cuboidal epithelium. Histopathologically, the tumor was diagnosed as metanephric stromal tumor. Metanephric stromal tumor is a rare renal neoplasm of childhood that can present as a cystic mass, and the solid component can go radiologically undetected because of the blurring infiltrative margins. By presenting this rare entity, the authors suggest that this should be included in the differential diagnosis, thereby helping to avoid complications and unnecessary treatment.

Endonasal endoscopic approach for the resection of chondroid chordoma with skull base involvement.

Chordoma is an uncommon tumor of bone that is believed to develop from remnants of the notochord. The chondroid variant of chordomas contains elements possessing both chordoma and cartilaginous tissues. Chondroid chordomas occur almost exclusively in the sphenooccipital region of the skull base. Primary treatment with surgical excision and radiotherapy for residual or recurrent tumor is recommended. Here, we describe a patient with chondroid chordoma with skull base involvement who underwent an expanded endonasal endoscopic approach for complete resection. In conclusion, endonasal endoscopic approach should be kept in mind for the resection of carefully selected chondroid chordomas with skull base involvement because of its minimally invasive characteristics.

Sertoliform cystadenoma: a case with overlapping features.

The 1st pediatric case of sertoliform cystadenoma with unique features is described herein. The patient is a 6-year-old boy who presented with gynecomastia and a left testicular cystic mass. Histopathologically the tumor was found to originate from the rete channels, filling and distending them with areas of mural Sertoli cell proliferations reminiscent of large cell Sertoli cell tumor (noncalcifying form) and showing widespread intratubular Sertoli cell proliferation islands in the vicinity. Histopathologic and immunohistochemical features are described in light of the relevant literature.