Background and study aims: We aimed to determine the feasibility of obtaining selective fluorescence of precancerous/cancerous lesions in the colon with a new fluorescence video endoscope system in combination with the selective photosensitizer precursor hexaminolevulinate (HAL), and to carry out a dose-finding study with evaluation of the optimal dose and application time.
Patients and methods: 12 patients with colorectal lesions underwent sensitization with locally applied HAL enemas in two concentrations (0.8 mmol and 1.6 mmol). The examination was conducted either 30 or 60 minutes after rectal administration of the sensitizer, using a special light source capable of delivering either white or blue excitation light. Red fluorescence induced by illumination with blue light was detected via a prototype fluorescence video colonoscope. Biopsies were taken from suspicious areas found with white or blue light. Corresponding endoscopic, fluorescence, and microscopic findings were compared.
Results: Using histological findings as the gold standard, 52/53 of the premalignant/malignant lesions showed red fluorescence under the photodynamic diagnosis (PDD) examination; 38/53 were detected with white-light endoscopy. The PDD mode showed 28 % more polyps than did white-light endoscopic imaging. The greatest fluorescence intensity in precancerous lesions was found with retention for 60 minutes of 500 ml of 1.6 mmol HAL.
Conclusions: Administration of HAL enema induces selective lesion fluorescence and increases the lesion detection rate in patients with colorectal adenoma and early carcinoma.
References
1
Pickhardt P J, Nugent P A, Mysliwiec P A. et al .
Location of adenomas missed by optical colonoscopy.
Ann Intern Med.
2004;
141
352-359
2
Kiesslich R, Moenk S, Reinhardt K. et al .
Methylene blue-aided chromoendoscopy for the detection of intraepithelial neoplasia and colon cancer in ulcerative colitis.
Gastroenterology.
2003;
124
880-888
3
Hurlstone D P, Cross S S, Slater R. et al .
Detecting diminutive colorectal lesions at colonoscopy: a randomised controlled trial of pan-colonic versus targeted chromoscopy.
Gut.
2004;
53
376-380
4
Messmann H, Endlicher E, Freunek G. et al .
Fluorescence endoscopy for the detection of low and high grade dysplasia in ulcerative colitis using systemic or local 5-aminolaevulinic acid sensitisation.
Gut.
2003;
52
1003-1007
5
Mayinger B, Guenther K, Horner P. et al .
Diagnosis of rectal cancer and adenoma with light-induced autofluorescence spectroscopy.
J Photochem Photobiol B.
2003;
70
13-20
6
Mayinger B, Reh H, Hochberger J, Hahn E G.
Endoscopic photodynamic diagnosis: oral aminolevulinic acid is a marker of GI cancer and dysplastic lesions.
Gastrointest Endosc.
1999;
50
242-246
7
Mayinger B, Neidhardt S, Reh H. et al .
Fluorescence induced with 5-aminolevulinic acid for the endoscopic detection and follow-up of esophageal lesions.
Gastrointest Endosc.
2001;
54
572-578
8
Endlicher E, Knuechel R, Hauser T. et al .
Endoscopic fluorescence detection of low and high grade dysplasia in Barrett’s oesophagus using systemic or local 5-aminolaevulinic acid sensitisation.
Gut.
2001;
48
314-319
9
Messmann H, Endlicher E, Freunek G. et al .
Fluorescence endoscopy for the detection of low and high grade dysplasia in ulcerative colitis using systemic or local 5-aminolaevulinic acid sensitisation.
Gut.
2003;
52
1003-1007
10
Ochsenkuhn T, Tillack C, Stepp H. et al .
Low frequency of colorectal dysplasia in patients with long-standing inflammatory bowel disease colitis; detection by fluorescence endoscopy.
Endoscopy.
2006;
38
477-482
11
Endlicher E, Rümmele P, Hausmann F. et al .
Detection of dysplastic lesions by fluorescence in a model of chronic colitis in rats after local application of 5-aminolevulinic acid and its esterified derivatives.
Photochem Photobiol.
2004;
79
189-192
12
Endlicher E, Gelbmann C M, Knüchel R. et al .
Hexaminolevulinate-induced fluorescence endoscopy in patients with rectal adenoma and cancer: a pilot study.
Gastrointest Endosc.
2004;
60
449-454
13
Klem B, Lappin G, Nicholson S. et al .
Determination of the bioavailability of [14C]-hexaminolevulinate using accelerator mass spectrometry after intravesical administration in human volunteers.
J Clin Pharmacol.
2006;
46
456-460
