RESUMEN
The characteristic immunoprofile for the diagnosis of synovial sarcoma, a neoplasm of unclear tissue origin, is expression of transducer-like enhancer of split 1 (TLE-1), CD99, partial expression of cytokeratin, and epithelial membrane antigen by immunohistochemistry (IHC). Diagnostic dilemma or misdiagnosis can occur due to overlap in IHC and morphology with carcinomas, and particularly poorly differentiated and metastatic tumors. The frequency of TLE-1 and CD99 expression in carcinomas by IHC has not been previously assessed. We evaluated TLE-1 and CD99 expression in various carcinomas and evaluated the expression of the SS18 (SYT) gene rearrangement (a characteristic biomarker for synovial sarcoma) in tumors with TLE-1 and/or CD99 expression. Immunostains of TLE-1 and CD99 were performed in 100 various carcinomas. Seven of the 98 cases (7%) of carcinomas showed TLE-1 expression, including 1 each of prostate adenocarcinoma (ADCA), esophageal ADCA, basal cell carcinoma, adrenocortical carcinoma, endometrial ADCA, ovarian serous carcinoma, and small cell carcinoma. Twenty-one of the 100 cases (21%) of carcinomas demonstrated CD99 expression, including 6 prostate ADCA, 3 esophageal ADCA, 5 squamous cell carcinomas, 2 hepatocellular carcinomas, 1 each for endometrial ADCA, renal cell carcinoma, urothelial cell carcinoma, neuroendocrine carcinoma, and mucoepidermoid carcinoma. An esophageal ADCA was positive for both TLE-1 and CD99. None of the carcinomas with positive TLE-1 (n=7) or CD99 (n=21) by IHC showed SS18 gene rearrangement by fluorescent in situ hybridization. TLE-1 and CD99 expression were identified in 7% and 21% of carcinomas, respectively. This is a potential pitfall in the IHC interpretation for diagnosis of synovial sarcoma. SS18 gene rearrangement by fluorescent in situ hybridization is helpful for the diagnostically challenging cases, either for confirmation or exclusion of synovial sarcoma.
Asunto(s)
Antígeno 12E7/metabolismo , Biomarcadores de Tumor/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Sarcoma Sinovial/metabolismo , Proteínas Co-Represoras , Errores Diagnósticos/prevención & control , Reordenamiento Génico , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genética , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/genéticaRESUMEN
BACKGROUND: Anaplastic lymphoma kinase (ALK) gene rearrangement analysis by fluorescence in situ hybridization (FISH) is one of the standard molecular tests for targeted therapy of lung adenocarcinoma. However, insufficient cell block cellularity may impede molecular testing. A recent study showed that Diff-Quik (DQ) stained cytology smear is suitable for ALK by FISH. AIMS: The aim of our study was to observe the impact of destaining intervals on the quality of FISH signals and determine if DQ smears without destaining would allow FISH analysis. MATERIALS AND METHODS: Thirty-five DQ smears from 27 cases of lung adenocarcinoma were analyzed for ALK gene rearrangement by FISH. Twenty three DQ smears were destained for different intervals, including 30 s (13 cases), 1 min (6 cases), or 2 min (4 cases). Twelve DQ smears were not subjected to destaining. For further validation, FISH signals in 8 smears and 6 cell blocks were compared with the paired destained DQ smears. The signal quality was semi-quantified and analyzed with Chi-squared test. RESULTS: Of the total 27 selected cases, three (11%) were positive for ALK gene rearrangement, whereas 24 (89%) were negative. FISH signal was satisfactory in all DQ smears. There was no significant difference in the quality of signal among smears with different destaining intervals (P = 0.55) or between smears with and without destaining (P = 0.41). DQ smears without destaining showed identical FISH results and similar or better signals as compared with paired destained smears and cell blocks in all cases. CONCLUSIONS: Duration of destaining intervals does not impact the quality of FISH signal on DQ smears. Destaining of DQ smears is not necessary for ALK by FISH.
RESUMEN
Expression of the transducin-like enhancer of split 1 (TLE1) by immunohistochemistry (IHC) has been widely used as a biomarker for the diagnosis of synovial sarcoma. Although TLE1 expression can be identified in more than 90% of synovial sarcomas, positive staining has been reported in up to one third of nonsynovial sarcomas, including peripheral nerve sheath tumors and neoplasms of fibrous and adipose tissues. The low specificity of this test in soft tissue tumors raises concern on its clinical application as a diagnostic biomarker. As synovial sarcoma is frequent among the differential diagnosis of unclassified high-grade sarcomas, and considering that the specificity of TLE1 antibody in this tumor group remains unclear, we evaluated TLE1 expression by IHC in 42 unclassified high-grade sarcomas. SS18 (SYT) gene break-apart analyses by fluorescence in situ hybridization were simultaneously performed as a gold standard biomarker for synovial sarcoma. Five cases that were positive for the SS18 break-apart by fluorescence in situ hybridization were also positive for TLE1 by IHC, whereas the remaining 37 cases negative for SS18 break-apart were all negative for TLE1. The results showed no evidence of nonspecific TLE1 expression in the nonsynovial high-grade sarcomas. We concluded that TLE1 is a highly specific biomarker for synovial sarcoma in the setting of differential diagnosis of unclassified high-grade sarcomas.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de Tejido Adiposo/diagnóstico , Neoplasias de Tejido Fibroso/diagnóstico , Neoplasias de la Vaina del Nervio/diagnóstico , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Represoras/metabolismo , Sarcoma Sinovial/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Co-Represoras , Diagnóstico Diferencial , Femenino , Regulación de la Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias de Tejido Adiposo/patología , Neoplasias de Tejido Fibroso/patología , Neoplasias de la Vaina del Nervio/patología , Proteínas Represoras/genética , Sarcoma Sinovial/patología , Sensibilidad y Especificidad , Adulto JovenRESUMEN
Myxoid liposarcoma with or without a round cell component is the most common subtype of liposarcoma. The diagnosis of myxoid liposarcoma could be challenging with histology, as a variety of soft tissue tumors with myxoid change might mimic myxoid liposarcoma, especially on small biopsy tissues. Chromosomal translocations of t(12,16) (q13;p11) and t(12;22) (q13;q12), rendering gene fusions of DDIT3 (previously CHOP) with FUS and EWSR1, have been found to be characteristic of myxoid liposarcoma, and were identifiable in more than 95% cases. These genetic alterations, therefore, are ideal as molecular markers to facilitate the diagnosis of this type of tumor. DDIT3 (12q13) dual-color break-apart rearrangement probe for fluorescence in situ hybridization has been commercially available. However, its consistency with DDIT3-associated gene fusion and its clinical use, including sensitivity and specificity, have not been adequately evaluated. In this study, we assessed the locus specificity of the probe on metaphase, and then tested it on 8 cases of myxoid liposarcoma, 12 cases of other sarcomas, and 18 cases of tumors with myxoid differentiation. All 8 myxoid liposarcomas showed DDIT3 gene break-apart, whereas all 12 other sarcomas were negative. All the cases with DDIT3 break-apart also showed FUS-DDIT3 fusion by reverse transcription-polymerase chain reaction, with 100% consistency. In addition, the FISH assay has been clinically applied on 18 myxoid tumors with promising outcome. In conclusion, FISH with DDIT3 break-apart probe is a highly sensitive and specific assay for detection of DDIT3-associated gene fusions, and therefore is a valuable adjunct in diagnosis or differential diagnosis of myxoid liposarcoma.
Asunto(s)
Liposarcoma Mixoide/diagnóstico , Factor de Transcripción CHOP/genética , Biomarcadores de Tumor , Fusión Génica , Humanos , Hibridación Fluorescente in Situ/métodos , Liposarcoma Mixoide/genética , Liposarcoma Mixoide/patología , Análisis de Secuencia de ADN , Translocación GenéticaRESUMEN
BACKGROUND: Recent studies have shown that KRAS mutations are negative predictors of benefit from both adjuvant chemotherapy and anti-EGFR directed therapies for non-small cell lung carcinoma (NSCLC). Needle core biopsy, cytology specimen and resected tissue have all been used for KRAS mutational analysis of malignant lung tumors. However, studies validating the correlation between needle core biopsy/cytology specimen and resected tissue, histologic reference standard for KRAS mutational analysis are lacking. We retrospectively compared the KRAS mutation detection on cytology specimen or needle core biopsy with corresponding resected malignant neoplasm of lung, the histologic reference standard for mutational analysis. METHOD: Twenty-seven samples including 8 cell blocks, 9 cytology smears and 10 needle core biopsies, and corresponding 22 resected malignant tumor of lung were correlated for KRAS mutational analysis. In cases where cell block material did not correspond with results on resected specimen, cytology smears of corresponding cases were microdissected for isolation of DNA. RESULTS: The needle core biopsy specimens and the corresponding surgical resections showed 100% concordant results for KRAS mutational analysis. KRAS mutation was detected in 4 out of 8 cell blocks, compared to 7 out of 8 corresponding surgical resections. Low cellularity (2 cases) and failure to retrieve DNA (1case) resulted in lack of correlation in 3 cases with cell blocks. However, cytology smears in these 3 cases confirmed the KRAS mutation noted in corresponding surgical resections. Overall concordance between cytology smears and corresponding surgical resections was 89% (8 of 9 cases). KRAS mutation was detected in 1 of the 9 cytology smears and was lacking in corresponding surgically resection. CONCLUSION: Cytology specimen and needle core biopsies provide adequate material for KRAS mutational analysis. Excellent mutational analysis concordance between cytology specimen/needle core biopsies and resected tumor suggests that predictive marker based therapeutic decision need not shift to more invasive surgical procedures.
RESUMEN
TMPRSS2 gene fusions with ETS transcription factor family members ERG, ETV1, or ETV4 have been recently discovered as a common molecular event in prostate cancer. Much attention has been focused on exploring their clinical application as a genetic tumor marker for the diagnosis, prognosis, and prediction of response to therapy. Although several studies have been done, the clinical utility of TMPRSS2 genetic alterations as biomarkers for prostate carcinoma remains indeterminate. In this study, we examined adenocarcinomas, prostatic intraepithelial neoplasia (PIN), and normal epithelium of the prostate retrieved from radical prostatectomy specimens to determine the frequency, specificity, tissue heterogeneity, and prognostic value of TMPRSS2 genetic alterations using a direct-labeled TMPRSS2 dual-color break-apart fluorescence in situ hybridization (FISH) probe cocktail designed to detect all known TMPRSS2-associated deletions or translocations. Seventy-one patients (161 samples) with normal prostate tissue, 60 patients (153 samples) with PIN, and 61 patients (142 samples) with carcinoma in formalin-fixed paraffin-embedded tissue microarrays were tested. None of the 161 normal prostate samples showed TMPRSS2 translocation or deletion. Sixty-two percent patients of prostate carcinomas demonstrated TMPRSS2 gene alterations, including 39% with translocation, 16% with deletion, and 7% with a mixed pattern. Tissue heterogeneity for TMPRSS2 gene alterations was identified in 28% of prostate carcinomas. No difference in the frequency of TMPRSS2 gene alterations was found between Gleason 6 and 7 tumors. Seventeen percent of PIN had TMPRSS2 gene alterations and showed the same FISH patterns as in the carcinomas from respective prostatectomy specimens. The TMPRSS2 dual-color break-apart FISH probe cocktail provides a simple and reliable method for the detection of TMPRSS2-related genetic alterations in formalin-fixed paraffin-embedded tissue. TMPRSS2 genetic alterations detectable by this method are strictly restricted in prostate neoplasia, and can be identified in the majority of prostate carcinomas. Tissue heterogeneity for TMPRSS2 alterations is common, and it should be considered when sampling and evaluating biopsy specimens.
Asunto(s)
Epitelio/patología , Hibridación Fluorescente in Situ/métodos , Patología Molecular/métodos , Próstata/patología , Neoplasias de la Próstata/patología , Serina Endopeptidasas/genética , Adenocarcinoma/patología , Eliminación de Gen , Marcadores Genéticos , Humanos , Masculino , Neoplasia Intraepitelial Prostática/patología , Translocación GenéticaRESUMEN
HER2 gene amplification by fluorescence in situ hybridization and protein expression by immunohistochemistry (IHC) have been used for prognosis and guiding treatment of invasive ductal carcinoma of the breast with trastuzumab. Accurate evaluation of HER2 status is important in the management of patients with candidacy for the HER2-targeting therapy. Despite previous studies, effects of polysomy of chromosome 17, at which HER2 is located, on HER2 protein expression remains controversial. In this study, we calculated the average copy numbers of HER2 and chromosome 17 (CEP17) per nucleus in 109 cases of invasive breast carcinoma and analyzed their correlations with the HER2/CEP17 ratio and protein expression. As expected, there were close correlations between HER2 protein expression and the HER2/CEP17 ratio (CC: 0.49, P<0.001), along with the HER2 copy number per nucleus (CC: 0.48, P<0.001) and between the CEP17 copy number per nucleus and the HER2 copy number per nucleus (CC: 0.45, P<0.001). Correlation between the CEP17 copy number per nucleus and the HER2/CEP17 ratio was not significant (CC: 0.2, P>0.05). There was a weak, but statistically insignificant, correlation between the CEP17 copy number per nucleus and HER2 protein expression by IHC (CC: 0.26, P>0.05). The cases were then grouped on the basis of the amplification of the HER2 gene by fluorescence in situ hybridization. In the cases that showed no amplification, there was a significantly higher CEP17 copy number per nucleus in cases with strong HER2 protein expression (2.99) when compared with cases with weak (2.39) or absent (1.86) expression. In conclusion, a high HER2 gene copy number-associated polysomy 17 is a significant contributing factor in HER2 protein overexpression in unamplified invasive breast carcinomas. Cases without HER2 amplification, but carrying polysomy 17, should be further evaluated for HER2 protein overexpression by IHC. Those with polysomy 17-associated HER2 protein overexpression, like any other IHC+ ones, should be eligible candidates for trastuzumab therapy.
Asunto(s)
Neoplasias de la Mama/patología , Carcinoma/patología , Cromosomas Humanos Par 17 , Dosificación de Gen , Receptor ErbB-2/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica/métodos , Hibridación Fluorescente in Situ/métodos , Persona de Mediana Edad , PoliploidíaRESUMEN
Poorly differentiated synovial sarcomas are diagnostically challenging soft tissue tumors. They can be indistinguishable from other "small blue cell tumors" based on morphology and even immunohistochemical studies. Here we report a rare case of poorly differentiated metastatic synovial sarcoma to lung without known primary, diagnosed with molecular genetic analysis. The tumor was negative for EMA and cytokeratin, previously reported as the most sensitive immunostaining markers for synovial sarcomas. SYT-SSX gene fusion, characteristic for synovial sarcoma, was identified in this case by FISH and RT-PCR assays.
Asunto(s)
Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Sarcoma Sinovial/genética , Adulto , Biopsia , Cromosomas Humanos Par 18 , Cromosomas Humanos X , Estudios de Seguimiento , Humanos , Inmunohistoquímica/métodos , Hibridación Fluorescente in Situ , Masculino , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Proteínas de Fusión Oncogénica/genética , Proteínas Represoras/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/secundario , Análisis de Secuencia de ADN , Translocación GenéticaRESUMEN
Chromosomal translocations of t(2;13)(q35;q14) and t(1;13)(p36;q14), resulting in PAX3-FOXO1 (FKHR) and PAX7-FOXO1 (FKHR) gene fusions, have been found to be specific molecular markers for alveolar rhabdomyosarcomas (ARMS) and can be identified in approximately 80% cases. As the prognosis of ARMS is worse than that of embryonal rhabdomyosarcomas (ERMS), it is important to accurately distinguish between these 2 subtypes. This distinction may be difficult on the basis of morphology alone. To detect the genetic alterations, reverse transcriptase polymerase chain reaction (RT-PCR) or dual-color dual-fusion fluorescence in situ hybridization (FISH) have been used in most studies so far. In this study, we used FOXO1 (FKHR) gene break-apart FISH probe, which can detect both of the translocations involving the FOXO1 gene, and tested 20 cases of rhabdomyosarcoma (RMS) including 6 cases of ARMS, 8 ERMS, 1 pleomorphic type, 5 not otherwise specified (RMS-NOS), and 10 non-RMS sarcomas. A home-brew RT-PCR that could detect both PAX3-FOXO1 and PAX7-FOXO1 was also performed. Four pathologists independently reviewed all RMS and a consensus diagnosis was also reached in discrepant cases. Histologic and molecular findings were correlated with clinical outcomes with an average of a 49-month follow-up. FOXO1 break-apart by FISH was positive in 4 of 6 (66%) ARMS and 2 of 5 (40%) RMS-NOS cases. All other cases, including all ERMS, were negative. RT-PCR assay confirmed all FISH results. While 2 of 6 (33%) RMS patients with a FOXO1 break-apart died of the disease, there were no deaths among the patients with negative result. The FOXO1 gene break-apart FISH probe is a simple and accurate tool to detect the translocations associated with ARMS. As characteristic genetic alterations of ARMS can be identified in 40% of RMS-NOS cases in our study, the FISH assay would provide an additional useful tool in the diagnosis and prognosis of ARMS, and an alternative to RT-PCR.
Asunto(s)
Rotura Cromosómica , Factores de Transcripción Forkhead/genética , Formaldehído/farmacología , Hibridación Fluorescente in Situ , Neoplasias de los Músculos/diagnóstico , Neoplasias de los Músculos/genética , Adhesión en Parafina , Rabdomiosarcoma Alveolar/diagnóstico , Rabdomiosarcoma Alveolar/genética , Adolescente , Adulto , Secuencia de Bases , Niño , Preescolar , Cromosomas Humanos Par 1 , Cromosomas Humanos Par 13 , Cromosomas Humanos Par 2 , Femenino , Proteína Forkhead Box O1 , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas de Fusión Oncogénica/genética , Pronóstico , Translocación Genética , Células Tumorales CultivadasRESUMEN
The potential ecological impact of exotic terrestrial planarians will be determined in part by their sensory abilities and predatory behavior. It has been suggested that these flatworms may only encounter their earthworm prey by chance, hence restricting the breadth of species they will feed upon and the number of microhabitats in which predator-prey interactions occur. We hypothesized that those flatworms that have already successfully invaded North America (genus Bipalium) actually detect and follow chemical trails of earthworms and possess the behavioral repertoire needed to feed on the prey in a range of microhabitats. We examined: (1) the tendency of Bipalium adventitium to follow chemical trails left by injured and un-injured earthworms; (2) the behavioral repertoire and predatory success of B. adventitium feeding on three earthworm species in subterranean tunnels; and (3) the response of flatworms to the reportedly defensive secretions of the earthworm Eisenia fetida in tunnels. B. adventitium detected and followed trails of earthworm mucus and secretions left by injured and un-injured earthworms. Flatworms followed trails on a range of substrates and pursued and captured three species of earthworms in subterranean tunnels, including individuals many times their mass. Although most behavior exhibited during underground attacks was similar to that reported for surface encounters, the flatworms also behaved in ways that blocked earthworm escape from tunnels. The flatworms were less successful at preying on E. fetida than on Lumbricus rubellus and Lumbricus terrestris in underground tunnels and showed some aversion to the secretions from E. fetida.