Performance characteristics of ultrasound-guided fine-needle aspiration of axillary lymph nodes for metastatic breast cancer employing rapid on-site evaluation of adequacy: analysis of 136 cases and review of the literature.

BACKGROUND: It has been demonstrated that axillary ultrasound-guided fine-needle aspiration (US-FNA) has excellent positive predictive value for the axillary lymph node status of patients with breast cancer before surgery or neoadjuvant therapy and, thus, can obviate the need for sentinel lymph node biopsy in FNA-positive patients. However, US-FNA has only moderate sensitivity, in part because of the collection of nondiagnostic or equivocal specimens. Rapid on-site evaluation for adequacy (ROSE) can improve definitive diagnosis rates but has not been well characterized in this setting. METHODS: One hundred thirty-three patients with breast carcinoma were identified who underwent 136 US-FNAs of axillary lymph nodes, all with ROSE, and the results were correlated with the diagnosis on a subsequent surgical procedure. RESULTS: The adequacy rate was 95.6% (130 of 136 FNAs), and a definitive diagnosis was made in 91.2% (124 of 136 FNAs). Among definite diagnoses, sensitivity was 75%, specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 79%. Sources of false-negative and potential false-positive diagnoses were evaluated among these cases and in the literature. CONCLUSIONS: Small metastasis size is the most common cause of false-negative results, whereas interpretation errors by pathologists are quite rare. ROSE appears to improve adequacy and definitive diagnosis rates and, thus, can more accurately triage patients to appropriate care.

Phosphohistone H3 and Ki-67 labeling indices in cytologic specimens from well-differentiated neuroendocrine tumors of the gastrointestinal tract and pancreas: a comparative analysis using automated image cytometry.

BACKGROUND: Ki-67 proliferation index was recently incorporated in the grading of neuroendocrine neoplasms (NENs) of the gastrointestinal tract (GIT) and pancreas. These are now divided into well-differentiated neuroendocrine tumors (WDNETs, grades 1 and 2) and poorly differentiated neuroendocrine carcinomas (grade 3). While Ki-67 is an established proliferation marker in NENs, phosphohistone H3 (PHH3), a newer marker of mitotic activity, is not. METHODS: We determined Ki-67 and PHH3 indices on cytologic samples from WDNETs of the GIT and pancreas using an automated cellular imaging system (ACIS®). RESULTS: There was a strong correlation between Ki-67 and PHH3 indices generated by ACIS on cytologic samples. However, in some cases the two stains caused conflicting grades within the same tumor. CONCLUSION: Both antibodies stain cells in different phases of the cell cycle which may cause discordant grades, thus affecting patient management and prognostication. Ki-67 staining is stronger than PHH3, making 'hot spots' easier to identify on ACIS. Ki-67 is more ideal than PHH3 for staining NENs, especially in tumors with borderline grades. Because PHH3 generates lower mitotic indices it should not be used as a proliferation marker in NENs until its expression has been further characterized.