Preservation of fine-needle aspiration specimens for future use in RNA-based molecular testing.

BACKGROUND: The application of ancillary molecular testing is becoming more important for the diagnosis and classification of disease. The use of fine-needle aspiration (FNA) biopsy as the means of sampling tumors in conjunction with molecular testing could be a powerful combination. FNA is minimally invasive, cost effective, and usually demonstrates accuracy comparable to diagnoses based on excisional biopsies. Quality control (QC) and test validation requirements for development of molecular tests impose a need for access to pre-existing clinical samples. Tissue banking of excisional biopsy specimens is frequently performed at large research institutions, but few have developed protocols for preservation of cytologic specimens. This study aimed to evaluate cryopreservation of FNA specimens as a method of maintaining cellular morphology and ribonucleic acid (RNA) integrity in banked tissues. METHODS: FNA specimens were obtained from fresh tumor resections, processed by using a cryopreservation protocol, and stored for up to 27 weeks. Upon retrieval, samples were made into slides for morphological evaluation, and RNA was extracted and assessed for integrity by using the Agilent Bioanalyzer (Agilent Technologies, Santa Clara, Calif). RESULTS: Cryopreserved specimens showed good cell morphology and, in many cases, yielded intact RNA. Cases showing moderate or severe RNA degradation could generally be associated with prolonged specimen handling or sampling of necrotic areas. CONCLUSIONS: FNA specimens can be stored in a manner that maintains cellular morphology and RNA integrity necessary for studies of gene expression. In addition to addressing quality control (QC) and test validation needs, cytology banks will be an invaluable resource for future molecular morphologic and diagnostic research studies.

Sinonasal eosinophilic angiocentric fibrosis: a report of four cases and review of literature.

Eosinophilic angiocentric fibrosis (EAF) is a rare, benign condition of unknown etiology involving the sinonasal tract and the upper respiratory airways, and rarely, larynx, and orbit. We report four cases of EAF identified, in three women and one man, aged 31, 57, 27, and 51 years, respectively. The patients complained of sinonasal obstructive symptoms of long duration, nasal masses, epiphora, and/or proptosis. Histologically, all cases demonstrated a dense fibrotic stroma with a perivascular "onion-skin" whorling pattern, and a dense inflammatory infiltrate consisting of lymphocytes, plasma cells, eosinophils, and some neutrophils. In addition, one patient demonstrated modest acute neutrophilic inflammation with focal endothelial proliferation. No patient exhibited clinical or histological evidence of Wegener's granulomatosis, granuloma faciale, Kimura's disease, and malignant lymphomas. Surgical excision was performed in all cases, and to date, medical therapy has been of limited help. The clinical and histopathological features and differential diagnoses of this underreported EAF condition are discussed.