INI1 immunohistochemical expression in glioblastoma: correlation with MGMT gene promoter methylation status and patient survival.

AIMS: INI1 expression and its correlation with MGMT gene promoter methylation status and follow-up was investigated in 77 surgically removed glioblastomas then treated with radiotherapy (RT) or RT plus temozolomide (TMZ). METHODS: INI1 was determined by immunohistochemistry and MGMT by methylation-specific PCR. RESULTS: INI1 was expressed in 83.1% of cases. The median overall survival (OS) was 13.6 months in INI1+ tumours and 7.2 months in INI1- tumours. 31.3% of patients with INI1+ tumours were alive compared with 15.4% of patients with INI1- tumours. MGMT methylation was detected in 31.2% of cases. OS was significantly different between patients with methylated tumours and un-methylated tumours (p < 0.04), and between patients with RT+ TMZ and RT alone (p < 0.001). Considering both treatment and MGMT, the difference in OS was significant (p < 0.002). The difference in OS according to MGMT and INI1 was significant (p < 0.04). The longest median OS was recorded among methylated and INI1+ tumours. Among un-methylated tumours, the median OS was 11.1 months in INI1+ and 6.5 months in INI1- tumours. No patients were alive with un-methylated and INI1- tumours. CONCLUSIONS: Loss of INI1 immunohistochemical expression in glioblastoma may be indicating an underlying molecular aberration accounting for the more aggressive clinical behaviour.

FISH analysis in cell touch preparations and cytological specimens from formalin-fixed fetal autopsies.

Postmortem studies on still-borns and miscarriages are important to define the sex and eventually the morphologic anomalies correlated to chromosomal aberrations. When the conditions for carrying out a cytogenetic study do not exist, these chromosomal alterations can be investigated by nucleic acid fluorescent in situ hybridization (FISH), which can be performed on interphase nuclei, usually on formalin-fixed paraffin embedded tissues or on fresh cytological specimens. The objective of the present study is to prove whether this technique can be successfully applied to formalin-fixed cell touch preparations and cytological specimens obtained from foetal autopsies. The study was carried out 12 abortions some of which were spontaneous and some of which were therapeutic. The materials were formalin-fixed. Cell touch preparations and cytological specimens were obtained. The FISH was performed using X/Y probes (Vysis) and the Aneuvysion Kit (05J38-030, Vysis), the probes being for chromosomes 13/21 and X/Y/18. To verify the reliability of the technique, the same reactions were also performed on fresh analogous materials. The slides were evaluable, and the probes hybridized to interphase nuclei showed distinct signals. All the samples were adequate for FISH analysis without any notable difference in the results. Moreover, it is technically possible to perform this analysis not only on fresh but particularly on formalin-fixed cytological specimens. On the other hand, the use of this type of cytological samples, as compared to formalin-fixed and paraffin embedded tissue sections, has the advantage of presenting intact, noncut nuclei with preserved cytomorphology, avoiding the problems of overlapping nuclei and making the identification of the real chromosomal arrangement easier.

Microsatellite and EGFR, HER2 and K-RAS analyses in sclerosing hemangioma of the lung.

Sclerosing hemangioma (SH) is an uncommon pulmonary tumor thought to derive from primitive respiratory epithelium consisting of 2 cell populations (cuboidal surface and polygonal stromal cells) and sharing some clinical characteristics (frequent occurrence in nonsmoking women of Asian ethnicity) with bronchioloalveolar carcinoma with which it has been suggested a possible common origin. We investigated 11 cases of SH by immunohistochemistry, fluorescence in situ hybridization, and polymerase chain reaction-based microsatellite and mutational analyses with particular emphasis on possible alterations of microsatellite loci located at tumor suppressor genes (FHIT, p16, Rb, and p53) involved in lung adenocarcinoma genesis and EGFR, HER2, and K-RAS genes. Although EGFR expression was observed in all tested cases, none showed HER2 immunostaining. Fluorescence in situ hybridization and mutational analysis of EGFR and HER2 and also K-RAS sequencing did not reveal molecular alterations, whereas allelic losses at p16 and Rb loci (4 and 2 out of 9 tested cases, respectively) with an identical microsatellite allelic loss pattern in both cuboidal and polygonal cells were observed. The finding of microsatellite alterations in chromosomal regions related to genes deeply involved in early stage lung adenocarcinoma could suggest a possible link between SH and bronchioloalveolar carcinoma, but tumor pathway promoted by EGFR, HER2, and K-RAS does not represent a common molecular mechanism of tumorigenesis. Microsatellite alterations identified in cuboidal and polygonal cells further confirm the clonal and neoplastic nature of both components of SH.

Role of chemotherapy and the receptor tyrosine kinases KIT, PDGFRalpha, PDGFRbeta, and Met in large-cell neuroendocrine carcinoma of the lung.

PURPOSE: Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a relatively uncommon, high-grade neuroendocrine tumor sharing several features with small-cell lung carcinoma (SCLC) but currently considered as a variant of non-SCLC and accordingly treated with poor results. Little is known about the optimal therapy of LCNEC and the possible therapeutic molecular targets. PATIENTS AND METHODS: We reviewed 83 patients with pure pulmonary LCNEC to investigate their clinicopathologic features, therapeutic strategy, and immunohistochemical expression and the mutational status of the receptor tyrosine kinases (RTKs) KIT, PDGFRalpha, PDGFRbeta, and Met. RESULTS: LCNEC histology predicted a dismal outcome (overall median survival, 17 months) even in stage I patients (5-year survival rate, 33%). LCNEC strongly expressed RTKs (KIT in 62.7% of patients, PDGFRalpha in 60.2%, PDGFRbeta in 81.9%, and Met in 47%), but no mutations were detected in the exons encoding for the relevant juxtamembrane domains. Tumor stage and size (> or = 3 cm) and Met expression were significantly correlated with survival. At univariate and multivariate analysis, SCLC-based chemotherapy (platinum-etoposide) was the most important variable correlating with survival, both in the adjuvant and metastatic settings (P < .0001). CONCLUSION: Pulmonary LCNEC represents an aggressive tumor requiring multimodal treatment even for resectable stage I disease, and LCNEC seems to respond to adjuvant platinum-etoposide-based chemotherapy. Patients who received this therapy had the best survival rate. Despite our failure in finding mutational events in the tested RTKs, the strong expression of KIT, PDGFRalpha, PDGFRbeta, and Met in tumor cells suggests an important role of these RTKs in LCNEC, and these RTKs seem to be attractive therapeutic targets.

Primary mixed adenocarcinoma and small cell carcinoma of the appendix: a clinicopathologic, immunohistochemical, and molecular study of a hitherto unreported tumor.

Appendiceal carcinoids range from well-differentiated endocrine tumor to well-differentiated endocrine carcinoma, while poorly differentiated (small cell) carcinoma has not been described in this site. We report herein a case of mixed intestinal-type adenocarcinoma associated with a small cell carcinoma arisen in a 35-year-old woman and clinically presenting as an appendiceal abscess. The resected tumor histologically appeared as a biphasic lesion composed of a nonmucinous adenocarcinoma closely juxtaposed with a poorly differentiated (small cell) endocrine carcinoma. The subsequent right hemicolectomy was unremarkable, but one pericolic lymph node showed a metastatic deposit consisting of the adenocarcinoma only. The patient thus underwent a chemotherapeutic protocol for colorectal cancer, and she is alive and well at the 65-month follow-up. Immunohistochemically, the adenocarcinoma strongly stained for cytokeratin 20 and carcinoembryonic antigen, while the endocrine component displayed a dot-like positivity for pan-cytokeratins and chromogranin. Of note, both components did not stain with CDX2 and p53. At genotypic analysis by microsatellite instability, both components shared many microsatellite alterations as well as a normal p53 gene setup, although small cell carcinoma harbored additional alterations. Clinical and molecular findings led us to consider this lesion as a clonal tumor in which the endocrine component seems to derive from a progressive differentiation of the adenocarcinoma following a glandular-to-endocrine sequence.

Alveolar adenoma of the lung: a clinicopathologic, immunohistochemical, and molecular study of an unusual case.

We describe an alveolar adenoma of the lung with 3 previously unreported findings, which expand both the clinical and the morphologic spectrum of this rare tumor: presentation as a cystic nodule, foci of mature adipocytes, and S-100 positivity of the mesenchymal cells. Furthermore, using a laser capture microdissection technique under microscope visualization, we analyzed multiple chromosomal loci in both the epithelial and mesenchymal components of the lesion, showing microsatellite alterations and loss of heterozygosity in the former but not in the latter.

Placental transmogrification of the lung: clinicopathologic, immunohistochemical and molecular study of two cases, with particular emphasis on the interstitial clear cells.

Two cases of placental transmogrification of the lung are reported. The lesions presented in the left lung, in one case as a giant bulla of the upper lobe and in the other as a cystic nodule of the lower lobe. A segmentectomy was performed in both cases, and the patients were alive and well 5 years and 2 months after surgery, respectively. In our opinion, pulmonary placental transmogrification is not a variant of emphysema, as generally considered, but rather probably represents a benign proliferation of immature interstitial clear cells with secondary cystic change. This report presents a histological, immunohistochemical, ultrastructural and molecular study of these peculiar cells, together with a review of the literature.