Javier Gómez-Román

Accurate identification of ALK positive lung carcinoma patients: Novel FDA-cleared automated fluorescence in situ hybridization scanning system and ultrasensitive immunohistochemistry

Background Based on the excellent results of the clinical trials with ALK-inhibitors, the importance of accurately identifying ALK positive lung cancer has never been greater. However, there are increasing number of recent publications addressing discordances between FISH and IHC. The controversy is further fuelled by the different regulatory approvals. This situation prompted us to investigate two ALK IHC antibodies (using a novel ultrasensitive detection-amplification kit) and an automated ALK FISH scanning system (FDA-cleared) in a series of non-small cell lung cancer tumor samples. Methods Forty-seven ALK FISH-positive and 56 ALK FISH-negative NSCLC samples were studied. All specimens were screened for ALK expression by two IHC antibodies (clone 5A4 from Novocastra and clone D5F3 from Ventana) and for ALK rearrangement by FISH (Vysis ALK FISH break-apart kit), which was automatically captured and scored by using Bioviews automated scanning system. Results All positive cases with the IHC antibodies were FISH-positive. There was only one IHC-negative case with both antibodies which showed a FISH-positive result. The overall sensitivity and specificity of the IHC in comparison with FISH were 98% and 100%, respectively. Conclusions The specificity of these ultrasensitive IHC assays may obviate the need for FISH confirmation in positive IHC cases. However, the likelihood of false negative IHC results strengthens the case for FISH testing, at least in some situations.

Incidental localized (solitary) epithelial mesothelioma of the pericardium Case report and literature review

Primary mesotheliomas of the pericardium are rare tumors. They may occur in diffuse, multiple, and localized forms. Most of the pericardial mesotheliomas are multiple or diffuse growths encasing the heart, localized forms being distinctly uncommon. We report a localized mesothelioma of the pericardium found incidentally at the autopsy of a 76-year-old woman. The neoplasm measured 3.6 x 2.4 x 2.5 cm., was well circumscribed, and affected the entire thickness of the myocardium extending from the epicardium to the endocardium of the anterior wall of the right ventricle. The tumor was epithelial in type, showed an immunohistochemical profile compatible with mesothelioma, and was DNA aneuploid. A review of the literature yielded four cases of localized pericardial mesothelioma, including the present. Most cases are seen in women and are of the epithelial variant. There is a wide age range at presentation. Localized mesotheliomas are capable of aggressive behavior. Nevertheless, in contrast to diffuse tumors, complete surgical excision may be curative. Differential diagnosis includes solitary fibrous tumor, synovial sarcoma, epithelioid angiosarcoma, and adenomatoid tumor of the pericardium.

Development of a novel splice array platform and its application in the identification of alternative splice variants in lung cancer

BackgroundMicroarrays strategies, which allow for the characterization of thousands of alternative splice forms in a single test, can be applied to identify differential alternative splicing events. In this study, a novel splice array approach was developed, including the design of a high-density oligonucleotide array, a labeling procedure, and an algorithm to identify splice events.ResultsThe array consisted of exon probes and thermodynamically balanced junction probes. Suboptimal probes were tagged and considered in the final analysis. An unbiased labeling protocol was developed using random primers. The algorithm used to distinguish changes in expression from changes in splicing was calibrated using internal non-spliced control sequences. The performance of this splice array was validated with artificial constructs for CDC6, VEGF, and PCBP4 isoforms. The platform was then applied to the analysis of differential splice forms in lung cancer samples compared to matched normal lung tissue. Overexpression of splice isoforms was identified for genes encoding CEACAM1, FHL-1, MLPH, and SUSD2. None of these splicing isoforms had been previously associated with lung cancer.ConclusionsThis methodology enables the detection of alternative splicing events in complex biological samples, providing a powerful tool to identify novel diagnostic and prognostic biomarkers for cancer and other pathologies.

Identification of Novel Deregulated RNA Metabolism-Related Genes in Non-Small Cell Lung Cancer

Lung cancer is a leading cause of cancer death worldwide. Several alterations in RNA metabolism have been found in lung cancer cells; this suggests that RNA metabolism-related molecules are involved in the development of this pathology. In this study, we searched for RNA metabolism-related genes that exhibit different expression levels between normal and tumor lung tissues. We identified eight genes differentially expressed in lung adenocarcinoma microarray datasets. Of these, seven were up-regulated whereas one was down-regulated. Interestingly, most of these genes had not previously been associated with lung cancer. These genes play diverse roles in mRNA metabolism: three are associated with the spliceosome (ASCL3L1, SNRPB and SNRPE), whereas others participate in RNA-related processes such as translation (MARS and MRPL3), mRNA stability (PCBPC1), mRNA transport (RAE), or mRNA editing (ADAR2, also known as ADARB1). Moreover, we found a high incidence of loss of heterozygosity at chromosome 21q22.3, where the ADAR2 locus is located, in NSCLC cell lines and primary tissues, suggesting that the downregulation of ADAR2 in lung cancer is associated with specific genetic losses. Finally, in a series of adenocarcinoma patients, the expression of five of the deregulated genes (ADAR2, MARS, RAE, SNRPB and SNRPE) correlated with prognosis. Taken together, these results support the hypothesis that changes in RNA metabolism are involved in the pathogenesis of lung cancer, and identify new potential targets for the treatment of this disease.

Papillary (chromophil) renal cell carcinoma with mucinous secretion.

We investigated the presence of mucin in a series of 20 papillary renal cell carcinomas. Acid mucin was present in three cases (15%), in which basophilic mucin secretion was evident with hematoxylin-eosin. This secretion reacted positively with Mayers mucicarmine, Alcian blue and high-iron diamine, but was negative for PAS in all the cases, indicating the presence of sulphomucins. We describe two different types of mucin secretion: luminal and intracytoplasmic. The secretion was abundant, diffuse or extensive, luminal in two cases and intracellular in numerous scattered tumor cells in one case. All tumors were < 3 cm in diameter (low grade, stage I). In the three mucin-secreting papillary tumors mentioned above, the immunohistochemical and lectin studies indicate both a proximal and a distal tubular staining pattern. Mucinous secretion in these tumors can be ascribed either to modulation or direct metaplasia of the tumor epithelium. Mucin production, despite its low frequency, can be considered an additional feature of papillary renal cell carcinoma. Thus, the presence of luminal or intracytoplasmic mucin deposition does not exclude papillary renal cell carcinoma from the differential diagnosis in cases of intra- or extrarenal carcinomas.

Recurrence of bronchioloalveolar carcinoma in donor lung after lung transplantation: microsatellite analysis demonstrates a recipient origin.

Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post‐transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non‐mucinous bronchioloalveolar carcinoma in a 43‐year‐old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty‐five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non‐mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease.

Prichard's structures of the fossa ovalis are not histogenetically related to cardiac myxoma.

Prichard’s structures of the fossa ovalis are not histogenetically related to cardiac myxoma

Anticipated diagnosis of left atrial myxoma following histological investigation of limb embolectomy specimens: a report of two cases.

Nonfamilial myxoma occurs as a random event. The tumor is rare and can mimic other diseases. Cardiac myxomas should always be considered as a source of embolization, which need meticulous investigation and prompt indication of surgical resection. Tumors with a villous surface are prone to embolize. We report two cases of cardiac myxoma presenting as acute ischemia of one or two limbs due to embolic phenomena. The patients were females aged 55 and 37 years. Histological study of emboli taken from obstructed limb arteries in the two patients showed a picture indicating systemic embolization of a cardiac myxoma. The embolic tissue fragments showed the gross characteristics (i.e. villous surface) of the cardiac tumor. Further echocardiography and surgical removal confirmed the cardiac myxoma. Immunohistochemical study of embolectomy material disclosed strong reactivity of the tumor cells for calretinin. The histological examination of the embolectomy material can anticipate the cardiac lesion and its gross features. Calretinin is a useful marker in the differential diagnosis of cardiac myxoma with a myxoid thrombus. The necessity of histological examination of the embolectomy material is stressed.

Spindle cell rhabdomyosarcoma in adults. A case report and literature review

Spindle cell rhabdomyosarcoma, a recently described variant of embryonal rhabdomyosarcoma in children, carries a favorable prognosis when compared with other types of rhabdomyosarcoma. This tumor is rare in adults, and only four cases have been documented previously. The clinicopathological study of such a case occurring in the retroperitoneal space of a 53-year-old man is herein reported. The patient died of uncontrolled local recurrence and hepatic metastases seven months after diagnosis. Based on the analysis of the data of the five cases reported, including the present one, it can be stated that spindle cell rhabdomyosarcoma in adults is not associated with the favorable outcome observed in the pediatric population.

Glandular Inclusions in Inguinal Hernia Sacs: A Clinicopathological Study of Six Cases

Glandular inclusions in inguinal hernia sacs are not frequent. We present six cases of inguinal hernia with this finding, which represents an incidence of 2.6% in males and shows a predominance in the prepubertal stage. Five patients showed cryptorchidism and two cases were related to congenital malformations of the single umbilical artery type and 47,XY chromosome disorder with chromosomal marker. The most important differential diagnosis must be made with normal histological structures such as the vas deferens or epididymis. The mean diameter of the inclusions was 0.1988 mm and there was a significant difference in size between the inclusions and the vas deferens, but not the epididymis. Differentiation from the latter is based on the absence of a well-developed muscular coat in the wall of the inclusions. It is important to recognize that these inclusions can occur in hernia sacs because of the clinical and medicolegal implications that arise if they are confused with true epididymis or vas deferens. They may arise from paratesticular embryonal remnants.