Fusion of the Paired Box 3 (PAX3) and Myocardin (MYOCD) Genes in Pediatric Rhabdomyosarcoma.

BACKGROUND/AIM: Fusions of the paired box 3 gene (PAX3 in 2q36) with different partners have been reported in rhabdomyosarcomas and biphenotypic sinonasal sarcomas. We herein report the myocardin (MYOCD on 17p12) gene as a novel PAX3-fusion partner in a pediatric tumor with adverse clinical outcome. MATERIALS AND METHODS: A rhabdomyo-sarcoma found in a 10-year-old girl was studied using a range of genetic methodologies. RESULTS: The karyotype of the tumor cells was 48,XX,add(2)(q11),+del(2)(q35),add(3)(q?25),-7, del(8)(p 21),-15, add(17)(p 11), + 20, +der(?) t(?; 15) (?;q15),+mar[8]/46,XX[2]. Fluorescence in situ hybridization detected PAX3 rearrangement whereas array comparative genomic hybridization revealed genomic imbalances affecting hundreds of genes, including MYCN, MYC, FOXO3, and the tumor suppressor gene TP53. A PAX3-MYOCD fusion transcript was found by RNA sequencing and confirmed by Sanger sequencing. CONCLUSION: The investigated rhabdomyosarcoma carried a novel PAX3-MYOCD fusion gene and extensive additional aberrations affecting the allelic balance of many genes, among them TP53 and members of MYC and FOXO families of transcription factors.

Recurrent Fusion of the GRB2 Associated Binding Protein 1 (GAB1) Gene With ABL Proto-oncogene 1 (ABL1) in Benign Pediatric Soft Tissue Tumors.

BACKGROUND/AIM: Fusions of the ABL proto-oncogene 1 gene (ABL1 in 9q34) are common in leukemias but rare in solid tumors. The most notable is the t(9;22)(q34;q11)/BCR-ABL1 coding for a chimeric tyrosine kinase. We herein report an ABL1-fusion in a pediatric tumor. MATERIALS AND METHODS: G-banding, fluorescence in situ hybridization, reverse transcription polymerase chain reaction and Sanger sequencing were performed on a soft tissue perineurioma found in the left musculus erector spinae of a child. RESULTS: A der(4)t(4;9)(q31;q34) and a fusion of the GRB2 associated binding protein 1 (GAB1 in 4q31) gene with ABL1 were found. A literature search revealed 3 more cases with similar genetic and clinicopathological characteristics: a soft tissue perineurioma with t(2;9;4)(p23;q34;q31) and ABL1 rearrangement, a soft tissue angiofibroma with a GAB1-ABL1 chimeric gene, and a solitary fibrous tumor carrying a der(4)t(4;9)(q31.1;q34). CONCLUSION: GAB1-ABL1 is a recurrent fusion gene in benign pediatric tumors.

Aggressive melanoma in an infant with congenital melanocytic nevus syndrome and multiple, NRAS and BRAF mutation-negative nodules.

We report the case of a newborn boy with multinodular NRAS and BRAF mutation-negative congenital melanocytic nevi and cerebral lesions compatible with congenital intraparenchymal melanosis. Histopathology from skin lesions showed atypical nodular melanocytic proliferation with marked melanocytic atypia and a large number of mitoses and apoptosis, indicating aggressive proliferation. The child developed several new subcutaneous tumors and multiple internal lesions, which were confirmed to be metastases, and died at 5 months of age. This case may represent an infantile melanoma developing from a giant congenital melanocytic nevus or a congenital melanoma.

Pancreatobiliary versus intestinal histologic type of differentiation is an independent prognostic factor in resected periampullary adenocarcinoma.

BACKGROUND: Resectable adenocarcinomas in the pancreatic head, by definition "periampullary", originate from ampullary, duodenal, biliary, or ductal pancreatic epithelium. Typically, periampullary adenocarcinomas have either intestinal or pancreatobiliary type of differentiation, and the type of differentiation might be prognostically more important than the anatomic site of origin. The aim of the study was to determine whether the histologic type of differentiation is an independent prognostic factor in periampullary adenocarcinoma, and whether tumour origin predicts the prognosis in pancreatobiliary type carcinomas independently of resection margin involvement, tumour size, nodal involvement, perineural and vascular infiltration, and degree of differentiation. METHODS: Histopathologic variables in 114 consecutively resected periampullary adenocarcinomas of pancreatobiliary (n = 67) and intestinal (n = 47) type differentiation were evaluated using a standardized, systematic protocol for evaluation of the resected specimen (study group). Histologic type of differentiation and tumour origin were compared as predictors of survival, and the results were validated by comparison with a historical control group consisting of 99 consecutive pancreaticoduodenectomies performed before standardization of histopathologic evaluation. Associations between histopathologic variables were evaluated by Chi-square and Mann-Whitney tests. Survival was estimated by the Kaplan-Meier method, comparing curves using log-rank test, and by univariate and multivariable Cox regression analysis. RESULTS: Both in the study group (n = 114) and in the historical control group (n = 99), the histologic type of differentiation independently predicted survival, while tumour origin predicted survival only in univariate analysis. Independent adverse predictors of survival in the study group were pancreatobiliary type differentiation (p < 0.001; HR 3.1; CI 1.8-5.1), regional lymph node involvement (p < 0.001; HR 2.5; CI 1.5-4.4), vessel involvement (p = 0.012; HR 1.9; CI 1.2-3.1), and increasing tumour diameter (measured in cm, p = 0.011; HR 1.3; CI 1.1-1.5). For pancreatobiliary differentiated adenocarcinomas (n = 67), lymph node status, vessel involvement, and tumour diameter remained independent prognostic factors, while tumour origin did not independently predict the prognosis due to significant association with tumour size (p < 0.001) and lymph node involvement (p = 0.004). CONCLUSION: Pancreatobiliary versus intestinal type of differentiation independently predicts poor prognosis after pancreaticoduodenectomy for periampullary adenocarcinoma. Lymph node involvement, vessel infiltration, and increasing tumour diameter are adverse predictors of survival in tumours with pancreatobiliary differentiation.

Resectable adenocarcinomas in the pancreatic head: the retroperitoneal resection margin is an independent prognostic factor.

BACKGROUND: The retroperitoneal margin is frequently microscopically tumour positive in non-curative periampullary adenocarcinoma resections. This margin should be evaluated by serial perpendicular sectioning. The aim of the study was to determine whether retroperitoneal margin involvement independently predicts survival after pancreaticoduodenectomy within a framework of standardized assessment of the resected specimens. METHODS: 114 consecutive macroscopically margin-free periampullary adenocarcinomas were examined according to a prospective standardized protocol for histopathologic evaluation. The retroperitoneal margin was assessed by serial perpendicular sectioning. The periampullary cancer origin (pancreas, ampulla, distal bile duct or duodenum) was registered prospectively and reevaluated retrospectively. Associations between histopathologic factors were evaluated by Chi-square test, Fisher's exact test, Kruskal-Wallis test, and Mann-Whitney test, as appropriate. Survival curves were calculated by the Kaplan-Meier method and compared using the log-rank test. Associations between histopathologic factors and survival were also evaluated by unadjusted and adjusted Cox regression analysis, including stepwise variable selection, in order to identify factors that independently predict a poor prognosis after periampullary adenocarcinoma resections. RESULTS: Microscopic resection margin involvement (R1 resection) was present in 40 tumours, of which 32 involved the retroperitoneal margin. Involvement of the retroperitoneal margin independently predicted a poor prognosis (p = 0.010; HR 1.89; CI 1.16-3.08) after presumed curative (R0 and R1) resection. In microscopically curative (R0) resections (n = 74), pancreatic tumour origin was the only factor that independently predicted a poor prognosis (p < 0.001; HR 4.71 for pancreatic versus ampullary; CI 2.13-10.4). CONCLUSION: Serial perpendicular sectioning of the retroperitoneal resection margin demonstrates that tumour involvement of this margin independently predicts survival after pancreaticoduodenectomy for adenocarcinoma. Periampullary tumour origin is the only histopathologic factor that independently predicts survival in microscopically curative (R0) resections.

[Sentinel lymph node biopsy in breast carcinoma: the experience from the Norwegian Radium Hospital]. / Biopsi av vaktpostlymfeknute ved brystkreft.

BACKGROUND: We report our experience with sentinel lymph node (SLN) biopsy in breast carcinoma. MATERIAL AND METHODS: The series included 51 women with invasive carcinoma and 3 ductal carcinoma in situ. The first 32 patients underwent axillary lymph node dissection (ALND) independently of the results of the SLN biopsy. SLN was evaluated on frozen sections, paraffin sections and with immunohistochemistry. RESULTS: The surgical detection rate was 98 % with a combined technique of radiocolloid and blue dye. Negative SLN was seen in 36 patients. ALND was done in 19 of these patients, with no metastases found in non-SLN. Metastases were found in SLN in 18 patients, in 3 patients detected only on immunohistochemistry. ALND was done in all positive cases. Three patients had positive non-SLN. INTERPRETATION: SLN biopsy seems accurate in breast carcinoma, performed with the use of radiotracer and blue dye. Immunohistochemistry increases the sensitivity of SLN biopsy.

Estrogen and progesterone hormone receptor status in breast carcinoma: comparison of immunocytochemistry and immunohistochemistry.

We evaluated the correlation between histologic and cytologic specimens in the determination of estrogen receptor (ER) and progesterone receptor (PR) status in breast carcinoma and investigated the causes of clinically significant discrepancies. We analyzed 70 immunoassays for ER and 60 for PR from 71 patients with breast carcinoma. Concordance between cytology and histology was 89% for ER and 63% for PR using scores from pathology reports. Concordance between cytology and histology was 98% for ER and 91% for PR using consensus scores (obtained after reevaluation by the team of pathologists). Thirty of 130 (23%) tests had clinically relevant discrepancies, 53% of which were caused by wrong interpretation of cytologic findings, 10% by wrong interpretation of histologic findings, 17% by sampling error and 20% were not available for reevaluation. Wrong interpretation of the results for ER and PR status in cytology was a far more frequent cause of clinically relevant discrepancies than sampling errors. The use of strict criteria is recommended.