Diagnostic accuracy of fine needle aspiration biopsy in preoperative diagnosis of patients with parotid gland masses.

BACKGROUND: The use of fine needle aspiration biopsy (FNAB) for diagnosis of parotid gland masses (PGM) is questioned, because of low sensitivity and the generalized belief requiring surgery for most parotid masses. Information available is retrospective. Our objective was to evaluate the diagnostic accuracy of FNAB for diagnosis of patients with PGM. METHODS: A prospective diagnostic test study was conducted in a cancer center from 2003 to 2007. FNAB was obtained from patients older than 18 years with PGM. Cytopathologist and histopathologist were blinded for all clinical information. The reference standard for diagnosis was the surgical pathology report. RESULTS: FNAB sensitivity and specificity values in diagnosis of malignancy were 0.923 (95% confidence interval [CI], 0.85-0.99) and 0.986 (95% CI, 0.96-1.00), respectively. Positive and negative likelihood ratios (LRs) were 64.6 (95% CI, 9.22-453) and 0.078 (95% CI 0.03-0.18), respectively. Negative LR of FNAB was strengthened (0.078-0.029) when negative diagnosis of FNAB was associated with tumor size <4 cm, definite borders, and homogeneous tumor mass observed by computed tomography (CT). CONCLUSION: Diagnostic accuracy for FNAB was very high. No clinical or radiological factors improved the positive LR of FNAB alone. Liberal use of FNAB of PGM is recommended.

Tetraploidy and chromosomal instability are early events during cervical carcinogenesis.

Chromosomal instability as manifested by increases in aneuploidy and structural chromosome aberrations is believed to play a critical role in the intermediate to late stages in the development of cervical malignancies. The current study was designed to determine the role of tetraploidy in the formation of aneuploidy and ascertain the occurrence of these alterations during the earlier stages of cervical carcinogenesis. Cervical cell samples, with diagnoses ranging from Normal to high-grade lesions, (HSIL) were obtained from 143 women and were evaluated for chromosomal alterations using dual-probe fluorescence in situ hybridization. Cervical cells from a subset of the group were also evaluated for chromosomal instability in the form of micronuclei. The frequencies of cells exhibiting either tetrasomy or aneusomy for Chromosomes 3 and 17 increased significantly with disease progression and displayed distinctive patterns where aneusomy was rarely present in the absence of tetrasomy. The frequencies of micronuclei that formed through either chromosomal loss or breakage increased significantly in both the low-grade and high-grade diagnostic categories and were highly correlated with both the number of tetrasomic and aneusomic cervical cells. In addition, a unique chromosomal alteration involving a significant non-random loss of Chromosome 17 specific to near-tetraploid aneusomic cells (trisomy 17 and tetrasomy 3) was observed. We conclude that tetraploidy and chromosomal instability are related events occurring during the early stages of cervical carcinogenesis that predispose cervical cells to the formation of aneuploidy frequently involving the loss of Chromosome 17.