Figure 3

Combined histopathological analysis and metabolic profiling of colon samples originating from a patient affected with an adenocarcinoma. A macroscopic view of the colectomy specimen (total length 10 cm) containing an invasive adenocarcinoma with a whitish fungating appearance and a section of the specimen stained with hematoxylin and eosin (H&E). (A) Histopathological analysis: The most invasive part of the tumor corresponds to boxes 1, 7 and 9, whereas normal mucosa is represented by boxes 3, 4, 5 and 6. Boxes 2 and 8 correspond to submucosa and serosa tissue respectively. Tissues corresponding to all the nine boxes were embedded in paraffin and stained with H&E for histological analysis (5 μm thickness). Evaluation of H&E staining was performed by light microscopy using a 10× eye-piece with a 20× or a 40× objective. The percentage of tumoral cells indicated was evaluated by a semi-quantitative method and by two pathologists to confirm the diagnosis. (B) Metabolic profiling: the histological sections have been replaced by the corresponding one-dimensional ¹H high resolution magic angle spinning nuclear magnetic resonance spectra. The most representative metabolites of control and adenocarcinoma samples are indicated on the spectra of samples 2 and 3. Samples 2 and 8 contain a higher amount of lipids (large peaks at 0.91 ppm, 1.30 ppm, 1.60 ppm, 2.04 ppm, 2.27 ppm and 2.80 ppm).