Increased detection rate and potential prognostic impact of disseminated tumor cells in patients undergoing endorectal ultrasound for rectal cancer.
BACKGROUND
Hematogenous tumor-cell dissemination during diagnostic and therapeutic procedures in patients with colorectal cancer has been demonstrated.


OBJECTIVE
The aim of this study was to investigate the extent of disseminated tumor cells in blood samples of rectal cancer patients after endorectal ultrasound and to determine its prognostic relevance.


METHODS
Peripheral venous blood samples from 45 patients with rectal cancer were taken before and after endorectal ultrasound. Blood samples were examined using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay to amplify cytokeratin 20 transcripts. Overall survival of the patients was calculated by the Kaplan-Meier method.


RESULTS
Disseminated tumor cells were detected in peripheral blood samples of 17 of 45 (38%) patients before and after endorectal ultrasound. Circulating tumor cells were found in 11 of 45 (24%) patients only after endorectal ultrasound (p=0.006). There was a clear trend toward a worse prognosis in patients with tumor cells in blood samples after endorectal ultrasound, but this difference was not statistically significant.


CONCLUSIONS
This study demonstrates significantly increased hematogenous tumor-cell dissemination after endorectal ultrasound in rectal cancer patients. Patients with tumor cells in blood samples after endorectal ultrasound tend to have a worse prognosis. The potential prognostic impact of this finding is presently unclear and has to be further validated in larger clinical trials.
Koch
Moritz
M
Department of Surgery, University of Heidelberg, INF 110, Heidelberg 69120, Germany.
Antolovic
Dalibor
D
Kienle
Peter
P
Horstmann
Johanna
J
Herfarth
Christian
C
von Knebel Doeberitz
Magnus
M
Weitz
Jürgen
J
D016099:Endoscopy, Gastrointestinal / Q000009:adverse effects; D019160:Endosonography / Q000009:adverse effects*; D005500:Follow-Up Studies; D006801:Humans; D053554:Keratin-20 / Q000097:blood / Q000235:genetics; D009366:Neoplasm Seeding; D009360:Neoplastic Cells, Circulating / Q000737:chemistry; D011379:Prognosis; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D053554:Keratin-20