FISH cytogenetics and prognosis in breast and non-small cell lung cancers

Clinical value of DNA content assessment in endometrial cancer

Endometrial carcinoma (EC) is the most common gynecologic cancer in industrialized countries. Traditional prognostic markers include FIGO stage, histologic subtype, and histologic grade. DNA ploidy was introduced as a prognostic marker 30 years ago, and the majority of published literature demonstrates significant associations between tumor aneuploidy and poorer prognosis in EC. However, ploidy analysis is not routinely implemented in the clinic. We reviewed the literature on clinical value of ploidy measured by DNA content as a prognostic marker, and its potential role as a predictive marker in EC.  PubMed was searched for papers evaluating the prognostic or predictive role of ploidy in EC. Search criteria were "DNA ploidy prognosis/predictive value endometrial cancer/carcinoma". Only articles written in English, published year 2000 or later were included.  The majority of the studies demonstrated highly significant correlation between DNA index (DI) and survival, in univariate analysis including stages I-IV, and in subgroup analysis of stage I and stage I-II EC. Several studies also showed significant association between DI and survival in multivariate analysis. Few studies have evaluated DI as a prognostic marker in a prospective setting. No studies evaluating DI as a predictive marker in EC were identified. In other cancer types, ploidy has been linked to prediction of response to hormonal therapy and chemotherapy.  Ploidy assessment in EC by DI is a strong prognostic marker. Still, its clinical applicability needs validation in a routine diagnostic, prospective setting with sufficient number of patients, characterized by state of the art histopathological evaluation and surgical staging.

Fluorescence in situ hybridization as adjunct to cytology improves the diagnosis and directs estimation of prognosis of malignant pleural effusions

Background

The identification of malignant cells in effusions by conventional cytology is hampered by its limited sensitivity and specificity. The aim of this study was to investigate the value of fluorescence in situ hybridization (FISH) as adjuncts to conventional cytologic examination in patients with malignant pleural effusions.

Methods

We conducted a retrospective cohort study of 93 inpatients with pleural effusions (72 malignant pleural effusions metastatic from 11 different organs and 21 benign) over 23 months. All the patients came from Chinese northeast areas. Aspirated pleural fluid underwent cytologic examination and fluorescence in situ hybridization (FISH) for aneuploidy. We used FISH in single-colour or if appropriate in dual-colour evaluation to detect chromosomal aberrations (chromosomes 7, 11, and 17) in effusion cells as markers of malignancy, to raise the diagnostic yield and identified the efficiency by diagnostic biopsy. Predominant cytogenetic anomalies and patterns of intratumor cytogenetic heterogeneity were brought in relation to overall survival rate.

Results

Cytology alone confirmed malignant pleural effusions in 45 of 72 patients (sensitivity 63%), whereas FISH alone positively identified 48 of 72 patients (sensitivity 67%). Both tests had high specificity in predicting benign effusions. If cytology and FISH were considered together, they exhibited 88% sensitivity and 94.5% specificity in discriminating benign and malignant effusions. Combined, the two assays were more sensitive than either test alone. Although the positive predictive value of each test was 94.5%, the negative predictive value of cytology and FISH combined was 78%, better than 47% and 44% for FISH and cytology alone, respectively. There was a significantly prolonged survival rate for patients with aneuploidy for chromosome 17.

Conclusions

FISH in combination with conventional cytology is a highly sensitive and specific diagnostic tool for detecting malignant cells in pleural effusions . The high sensitivity and specificity may be associated with geographic area and race. Simple numeric FISH anomalies may be prognostic.

High frequency of genetic alterations in non-small cell lung cancer detected by multi-target fluorescence in situ hybridization

Detection of genetic alterations could provide a tool as an adjuvant for the diagnosis of non-small cell lung cancer (NSCLC) and to define patients at risk for early relapse. In this study, a multi-target fluorescence in situ hybridization (FISH) assay was conducted to investigate the correlation between the alterations of chromosomes, including 5p15.2, 6p11.1-q11, 7p12, and 8q24.12-q24.13 (LaVysion Test), and clinicopathological variables, and to clarify the potential of the multi-target FISH assay in 37 NSCLC. The most notable finding was the higher frequency of a gain in chromosome 5p15.2 in early-stage (I+IIa) lung cancers. The frequency of the gain was 81.3% (16/22) in stage I tumors. The frequencies of gains in 6p11.1-q11 and 8q24.12-q24.13 were 61.5% (8/13) and 84.6% (11/13) in stage IIIa cancers, as compared with lower frequencies in stage I tumors at 25.0% and 31.3%, respectively. There was also a significant difference in the histological type. Our results suggest that a gain in 6p11.1-q11 and 8q24.12-q24.13 plays an important role in tumor progression and is associated with histological differentiation. On the other hand, gene amplification in the 5p region was one of the most consistent alterations in early-stage lung cancer, and thus a series of genes in the critical 5p15.2 region might potentially associated with the development of lung cancer.

The utility of fluorescence in-situ hybridization in the diagnosis of malignant pleural effusion

PURPOSE OF REVIEW

Molecular tools are used to refine the diagnosis of malignancy in pleural fluids. This review discusses the rationale and recent findings of the application of one of these tools, fluorescence in-situ hybridization, in pleural effusions.

RECENT FINDINGS

Aneuploidy (i.e., pronounced numeric and structural chromosomal changes) is a recurrent finding in cells of solid tumors. Different methods attempt to detect tumor-associated aneuploidy to prove micrometastasis in different compartments, such as urine, cerebrospinal fluid, bone marrow, and body fluids. In recent years, fluorescence in-situ hybridization analysis has proved viable for detecting metastasis based on the observation of matching patterns of chromosomal aneusomies in primary tumors and corresponding metastasis.

SUMMARY

Fluorescence in-situ hybridization analysis using specific probes for visualizing numeric aberrations in a microscopic evaluation (thus complementing routine cytologic evaluation) has been shown to be relatively simple, very robust, and thus applicable in material of lesser quality and more sensitive than routine cytology. Remarkably, dual-color fluorescence in-situ hybridization analysis allows for an efficient analysis in effusions, and the approach presented in this review proved to be more specific than other molecular procedures applied in effusions to detect malignancy, such as polymerase chain reaction. Prospective studies are needed to demonstrate that refinement of staging by fluorescence in-situ hybridization or polymerase chain reaction ('molecular upstaging') will translate into meaningful therapeutic consequences.

Prognostic value of chromosome 1 and 8 copy number in invasive ductal breast carcinoma among Iranian women: an interphase FISH analysis

Breast cancer is amongst the leading causes of death in women worldwide and the most common cancer amongst Iranian women. Unfortunately, the current clinical and histological criteria can only help 60 percent of women with breast cancer in diagnosis and long-term treatment. Therefore, genetic markers both at single gene and chromosomal level can play an important role in improving the diagnosis and prognosis of breast cancer patients. The aim of this retrospective study was to investigate the role of chromosome 1 and 8 copy number assessed by interphase fluorescence in situ hybridization (FISH), as prognostic parameters in 50 Iranian women, aged 35 to 64 years, with sporadic invasive ductal breast carcinoma. Chromosome 1 and 8 copy numbers were evaluated in relation to established clinicopathological parameters, the immunohistochemical markers ER, PR, P53 and cathepsin D, DNA index by flow cytometry, age and survival status of the patients. FISH using centromeric probes for chromosomes 1 and 8 was applied to interphase cell suspensions prepared from archived, Carnoyfixed tumor cells and selected paraffin-embedded tumor sections. Aneusomy for chromosomes 1 and 8 was present in all 50 patients to different levels. The total abnormality rate for chromosome 1 was 33.92 percent (4.24 percent monosomy and 29.68 percent polysomy), whereas for chromosome 8 this rate was 28.30 percent (6.48 percent monosomy and 21.82 percent polysomy). Statistically significant association (p<0.05) was demonstrated between monosomy 1 and patients' age below 50 years, and between monosomy 1 and poor survival, respectively. Disomy 8 was significantly associated with P53 expression. A borderline significant correlation was demonstrated between polysomy 8 and diploid DNA content, as well as between disomy 1 and disease-free status of the patients. Chromosome 1 and 8 copy numbers may be considered as useful prognostic markers in invasive ductal carcinoma of the breast.