Patent blue V and indocyanine green for fluorescence microimaging of human peritoneal carcinomatosis using probe-based confocal laser endomicroscopy

Probe-based confocal laser endomicroscopy intra-operative evaluation in ovarian cancer: definition of in vivo architectural patterns to determine resection strategies

OBJECTIVE

Probe-based confocal laser endomicroscopy (pCLE) is a novel real-time imaging technique that is potentially useful for accurately distinguishing between normal and cancerous tissues. The aim of this study was to describe the pCLE patterns of areas suggestive of tumors and evaluate the ability of the method to differentiate between normal and cancerous tissue during cytoreductive surgery for epithelial ovarian cancer.

METHODS

In vivo pCLE images and subsequent biopsies were acquired from various anatomical sites including the parietal and visceral peritoneum, ovaries, and omentum. Each endomicroscopic sequence was analyzed by highly experienced investigators using pCLE imaging for cancer diagnosis. Each pCLE sequence was compared with the histology of the corresponding specimens.

RESULTS

We enrolled 18 women with International Federation of Gynecology and Obstetrics stage III/IV high-grade serous epithelial ovarian cancer referred for primary or interval debulking surgery. A total of 112 biopsies were obtained for histologic analysis. The pCLE images of normal tissue showed a regular distribution of stromal fibers and consistent cellular architecture, regardless of the anatomical region, with vascularized areas characterized by regular vessels. Conversely, the extravasation of fluorescein, used as a contrast agent, was a distinguishing feature of malignant nodules, which were easily recognized by leakage and are typical of tumor-associated vessels. The leakage often surrounded the dark clusters of neoplastic cells. A substantial agreement between pCLE and histology emerged (k = 0.66), whereas only a fair concordance between the surgeon's intra-operative assessment and histology was found (k = 0.30).

CONCLUSIONS

Our results suggest that pCLE is a promising intra-operative technique to assist surgeons in accurately detecting peritoneal metastases in patients with advanced epithelial ovarian cancer, enhancing surgical radicality while avoiding unnecessary resection.

Fluorescence contrast-enhanced proliferative lesion imaging by enema administration of indocyanine green in a rat model of colon carcinogenesis

The fluorescent contrast agent indocyanine green (ICG) is approved by the Food and Drug Administration for clinical applications. We previously reported that cultured human colon tumor cells preferentially take up ICG by endocytic activity in association with disruption of their tight junctions. The present study explored ICG availability in fluorescence imaging of the colon to identify proliferative lesions during colonoscopy. The cellular uptake of ICG in cultured rat colon tumor cells was examined using live-cell imaging. Colon lesions in rats administered an ICG-containing enema were further assessed in rats with azoxymethane-induced colon carcinogenesis, using in vivo endoscopy, ex vivo microscopy, and immunofluorescence microscopy. The uptake of ICG by the cultured cells was temperature-dependent. The intracellular retention of the dye in the membrane trafficking system suggested endocytosis as the uptake mechanism. ICG administered via enema accumulated in colon proliferative lesions ranging from tiny aberrant crypt foci to adenomas and localized in proliferating cells. Fluorescence endoscopy detected these ICG-positive colonic proliferative lesions in vivo. The immunoreactivity of the tight-junction molecule occludin was altered in the proliferative lesions, suggesting the disruption of the integrity of tight junctions. These results suggest that fluorescence contrast-enhanced imaging following the administration of an ICG-containing enema can enhance the detection of mucosal proliferative lesions of the colon during colonoscopy. The tissue preference of ICG in the rat model evaluated in this study can be attributed to the disruption of tight junctions, which in turn promotes endocytosis by proliferative cells and the cellular uptake of ICG.

Patient optimization for surgery relating to Crohn's disease

The majority of patients with Crohn's disease require abdominal surgery during their lifetime, some of whom will require multiple operations. Postoperative complications are seen more frequently in patients requiring abdominal surgery for Crohn's disease than in patients requiring abdominal surgery for other conditions. In this article, we review the evidence supporting preoperative optimization, discussing strategies that potentially improve surgical outcomes and reduce perioperative morbidity and mortality. We discuss the roles of adequate cross-sectional imaging, nutritional optimization, appropriate adjustments of medical therapy, management of preoperative abscesses and phlegmons, smoking cessation and thromboembolic prophylaxis. We also review operation-related factors, and discuss their potential implications with respect to postoperative complications. Overall, the literature suggests that preoperative management has a major effect on postoperative outcomes.