Bioluminescence as gold standard for validation of optical imaging modalities in peritoneal carcinomatosis animal models.
BACKGROUND
The outcome of cytoreductive surgery in patients with peritoneal carcinomatosis is influenced by incomplete resection as a result of inadequate detection of a tumor, i.e. residual disease. The future perspective of complete resection, made possible by application of intraoperative near-infrared fluorescence imaging (NIRF), led to the development and validation of a bioluminescent colorectal peritoneal carcinomatosis xenograft rat model to act as the gold standard for the evaluation of new optical imaging modalities.


METHODS
Twenty nude rats were inoculated intraperitoneally with 2 × 10(6) luciferase-labeled human colorectal tumor cells (HT-29-luc-D6). The peritoneal carcinomatosis index (PCI) was estimated using visual observation (PCI-VO) and VO combined with bioluminescence imaging (PCI-BLI). Subsequently, the BL images were presented, and residual tumor tissue was localized by PCI-BLI scoring and compared with the PCI-VO.


RESULTS
BLI revealed additional tumor tissue, confirmed by HE staining, compared to VO alone in 7 out of 8 rats (p < 0.02).


CONCLUSIONS
The developed model turned out to be suitable. The use of BLI for tumor detection was more sensitive compared to VO alone. In this model, BLI significantly detected residual disease, and therefore, BLI can be denominated as the gold standard for the evaluation of optical imaging modalities like NIRF.
Department of Surgery, Division of Surgical Oncology, University of Groningen, Groningen, The Netherlands.
N J
NJ
Harlaar
J W
JW
Hesselink
J S
JS
de Jong
G M
GM
van Dam
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000556:secondary / Q000628:therapy; D000818:Animals; D015179:Colorectal Neoplasms; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D005260:Female; D019073:HT29 Cells; D006801:Humans; D007259:Infrared Rays; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008163:Luminescent Measurements / Q000379:methods*; D018365:Neoplasm, Residual / Q000175:diagnosis / Q000556:secondary / Q000628:therapy; D055620:Optical Phenomena; D010534:Peritoneal Neoplasms / Q000175:diagnosis* / Q000556:secondary / Q000628:therapy; D011379:Prognosis; D051381:Rats; D011923:Rats, Nude; D014183:Transplantation, Heterologous; D047368:Tumor Burden
D008156:Luciferases