Clinical interest in @entity910 ( @entity910 ) spectroscopy and photodynamic therapy (PDT) is growing rapidly and may ultimately lead to close parallel use of these techniques. However, variations in @entity910 due to photosensitizer retention as well as tissue damage and healing processes may interfere with autofluorescence-based diagnostic methods. We have investigated the compatibility of these two techniques by quantifying PDT-induced changes in @entity910 in the @entity1 esophagus. Fluorescence spectra were collected endoscopically at excitation wavelengths (lambda ex) of 337, 400 and 410 nm in 32 @entity1 . Measurements were performed immediately before and after PDT treatment with porfimer @entity1372 and during follow-up procedures. In the months following PDT regions of reepithelialized squamous showed reduced autofluorescence in comparison with untreated squamous regions (P = 0.0007). Photosensitizer fluorescence was undetectable with lambda ex = 337 nm during follow-up procedures, whereas for lambda ex = 400 and 410 nm porfimer @entity1372 fluorescence was noted for nearly a year after treatment. Therefore, residual photosensitizer fluorescence is likely to affect certain @entity910 -based diagnostic techniques during a period when @entity1 are at high risk for @entity5 recurrence. Modification of @entity910 systems and/or the use of alternative photosensitizers may be required to optimize the detection of lesions in the post-PDT @entity1 . Given the potential of @entity910 as a method for surveillance following @entity5 therapy, further investigation of the compatibility of specific @entity910 with @entity5 pharmaceuticals may be warranted.

Long-term effects of photodynamic therapy on fluorescence spectroscopy in the XXXX esophagus.

@entity1 :: ('9606', 'Species') :: ['human', 'patients', 'patient'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'cancer'] @entity1372 :: ('MESH:D012964', 'Chemical') :: ['sodium'] @entity910 :: ('MESH:D004409', 'Disease') :: ['laser-induced fluorescence', 'LIF approaches', 'LIF']
@entity1 :: (9606,Species) :: ['human']
