Search

BACKGROUND Biopsies from patients with high-risk (HR) non–muscle-invasive urothelial carcinoma (NMIUC), especially flat urothelial carcinoma in situ, frequently contain scant diagnostic material or denuded mucosa only, and this precludes further extensive genomic analysis. This study evaluated the use of next-generation sequencing (NGS) analysis of urine cytology material from patients with HR NMIUC in an attempt to identify genetic alterations that might correlate with clinical features and responses to bacille Calmette-Guerin (BCG) treatment. METHODS Forty-one cytology slides from patients with HR NMIUC treated with intravesical BCG were selected for this study. Histological confirmation was available for all cases. The specimens were subjected to NGS analysis with a customized targeted exome capture assay composed of 341 genes. RESULTS In this cohort, genomic alterations were successfully identified in all cytology samples. Mutations were detected down to a 2% allele frequency and chromosomal rearrangements including copy number alterations and gene fusions were identified. The most frequently altered genes included telomerase reverse transcriptase (TERT), tumor protein 53 (TP53), Erb-B2 receptor tyrosine kinase 2 (ERBB2), and chromatin remodeling genes such as lysine demethylase 6A (KDM6A) and AT-rich interaction domain 1A (ARID1A). For patients with matched tumor tissue, cytology specimens revealed all mutations detected in tissue as well as additional mutations, and this suggested that urine might more effectively capture the full genetic heterogeneity of disease than an individual cystectomy. Alterations in multiple genes correlated with clinical and histopathological features, including responses to BCG treatment, flat architecture versus papillary architecture, and smoking history. CONCLUSIONS Urine specimens can replace tissue as a substrate for NGS analysis of HR NMIUC. Several genomic alterations identified in urine specimens might be associated with histological features and clinical characteristics. Cancer Cytopathol 2017;125:416–26. © 2017 American Cancer Society.

BACKGROUND Mutation analysis for personalized treatment has become increasingly important in the management of different types of cancer. The advent of new DNA extraction protocols and sequencing platforms with reduced DNA input requirements might allow the use of cytology specimens for high-throughput mutation analysis. In this study, the authors evaluated the use of effusion fluid for next-generation sequencing-based, multigene mutation profiling. METHODS Four specimens from each of 5 patients who had at least stage III, high-grade serous ovarian carcinoma were selected: effusion fluid; frozen tumor; formalin-fixed, paraffin embedded tumor; and matched normal blood. Frozen tumors from each patient were previously characterized by The Cancer Genomic Atlas (TCGA). DNA was extracted from all specimens and was sequenced using a custom hybridization capture-based assay. Genomic alterations were compared among all specimens from each patient as well as with mutations reported in TCGA for the same tumors. RESULTS In total, 17 distinct somatic mutations were identified in the cohort. Ten of 17 mutations were reported in TCGA and were called in all 3 malignant specimens procured from the patients. Of the remaining 7 mutations, 2 were called in all 3 specimens, and the other 5 were sample-specific. Two mutations were detected only in the cytology specimens. Copy number profiles were concordant among the tumors analyzed. CONCLUSIONS Cytology specimens represent suitable material for high-throughput sequencing, because all mutations described by TCGA were independently identified in the effusion fluid. Differences in mutations detected in samples procured from the same patient may reflect tumor heterogeneity. Cancer (Cancer Cytopathol) 2015;123:289–97. © 2015 American Cancer Society.