gms | German Medical Science

62nd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Polish Society of Neurosurgeons (PNCH)

German Society of Neurosurgery (DGNC)

7 - 11 May 2011, Hamburg

Optical, label-free, spectroscopic analysis of pituitary adenomas

Meeting Abstract

  • M. Kirsch - Klinik für Neurochirurgie, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden
  • L. Mackenroth - Klinik für Neurochirurgie, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden
  • K. Geiger - Institut für Pathologie, Bereich Neuropathologie, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden
  • T. Pinzer - Klinik für Neurochirurgie, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden
  • G. Schackert - Klinik für Neurochirurgie, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden
  • G. Steiner - Klinisches Sensoring und Monitoring, Carl Gustav Carus Universitätsklinikum an der Technischen Universität Dresden

Deutsche Gesellschaft für Neurochirurgie. Polnische Gesellschaft für Neurochirurgen. 62. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgen (PNCH). Hamburg, 07.-11.05.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. DocP 074

DOI: 10.3205/11dgnc295, URN: urn:nbn:de:0183-11dgnc2951

Published: April 28, 2011

© 2011 Kirsch et al.
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Outline

Text

Objective: Hormonally active pituitary adenomas are associated with severe systemic morbidities independent of local tumor effects. Even small remnants of residual hormone-producing tumors such as growth hormone-producing tumors will maintain the aberrant pathologic state. The purpose of the current study is to analyze whether tumor remnants can be identified using marker-free optical imaging technologies, namely Fourier-transformed infrared spectroscopy (FTIR). The first set of experiments aim to introduce a classification of different adenoma types and evaluate spectroscopic differences between HGH-active and inactive tumors, as well as to differentiate normal pituitary from adenoma tissue.

Methods: 21 HGH+ and 19 hormonally inactive pituitary adenomas as well as 4 normal pituitaries from autopsy tissue were snap frozen, sectioned on CaF2 glass slides and submitted to FTIR measurements using a dedicated system with a focal plane array detector. Parallel sections were submitted to H&E, HGH- and Ki67 immunohistochemistry.

Results: A classification algorithm based on a two-step supervised non-linear discriminant analysis was developed to distinguish different tumor components without labelling. The classification is based upon spectral features, which mainly arise within the spectral regions of 1000 bis 1260 cm-1, in particular containing phosphate and sugar components, within the amid-1 and -2 regions (1515 bis 1700 cm-1). Cross-validation was performed for all measurements.

Conclusions: A purely optical, completely label-free spectroscopic classification of normal pituitary tissue vs. adenoma is possible. Even within HGH+ adenomas, regions of differential hormone production are identified. This technology is currently advanced to allow in situ analyses of adenoma remnants via a fiber optic probe.