Sensitive detection of occult XXXX by the reverse-transcriptase polymerase chain reaction.

@entity1 @entity4166 @entity0 @entity189 @entity3909 @entity1860
PURPOSE: Detection of @entity189 in @entity1 with @entity0 may aid the establishment of prognosis and development of new therapeutic approaches. To improve on existing methods of detection, we have developed a reverse-transcriptase polymerase chain reaction (RT-PCR) assay for @entity4166 ( @entity4166 ) transcripts to identify mammary @entity189 cells in the peripheral blood and bone marrow of @entity1 with @entity0 . @entity1 AND METHODS: Peripheral-blood or bone marrow samples obtained from 34 @entity1 with stages I to IV @entity0 and 39 control subjects without @entity0 were screened for @entity4166 mRNA by nested primer PCR. RESULTS: In reconstitution experiments, @entity4166 RT-PCR reliably detected 10 mammary @entity189 cells in 1 million normal peripheral-blood mononuclear (PBMN) cells. Four of 19 @entity1 with @entity0 had detectable @entity4166 transcript in peripheral blood. Five of six @entity1 with histologically negative bone marrow biopsies following preablative chemotherapy and before autologous bone marrow transplant (BMT) were positive by this assay. Stem-cell apheresis harvests obtained from one of these @entity1 and three additional @entity1 immediately before BMT were all @entity4166 -negative. @entity4166 RT-PCR analysis of CSF from a @entity0 @entity1 with known @entity3909 was also positive. Thirty-eight of 39 non- @entity0 @entity1 had negative @entity4166 RT-PCR assays. The one exception was a @entity1 with @entity1860 . CONCLUSION: RT-PCR of @entity4166 is a sensitive, specific, and rapid method for detection of occult mammary @entity189 cells in the peripheral blood and bone marrow of @entity1 with @entity0 . The presence of residual @entity0 cells in histologically normal bone marrow aspirates but not in stem-cell apheresis harvests is a frequent finding. This assay may be useful in diagnosing metastatic disease, as well as in monitoring the effectiveness of systemic therapy.
