DETECTION OF HETEROZYGOSITY LOSS IN MICRODISSECTED FINE-NEEDLE ASPIRATION SPECIMENS OF BREAST-CARCINOMA

OBJECTIVE: To use the polymerase chain reaction (PCR) to detect loss o f heterozygosity (LOH) in microdissected cells from cytologic smears o btained by fine needle aspiration (FNA) from 20 cases of invasive brea st carcinoma. STUDY DESIGN: In each case, histologic sections of the p rimary tumor were also available. Tumor and nontumor cells were dissec ted from both the cytologic smear and tissue section in all cases exce pt in three smears that showed only tumor cells. RESULTS: LOH was iden tified in 10 of 19 informative cases using two polymorphic DNA markers at chromosome 11q13 (INT-2, PYGM). The same results were obtained in both the cytologic and histologic specimens, including three cases tha t had hypocellular cytologic smears. CONCLUSION: FNA of breast lesions provides adequate samples for direct microdissection of the cytologic smear to defect LOH using PCR amplification.