FTIR microspectroscopy of selected rare diverse sub‐variants of carcinoma of the urinary bladder

Abstract

Urothelial carcinomas of the bladder are a heterogeneous group of tumours, although some histological sub-variants are rare and sparsely reported in the literature. Diagnosis of sub-variants from conventional urothelial carcinoma can be challenging, as they may mimic the morphology of other malignancies or benign tumours and therefore their distinction is important. For the first time, the spectral pathology of some of these sub-variants has been documented by infrared microspectroscopy and an attempt made to profile their biochemistry. It is important not only to identify and separate the cancer-associated epithelial tissue spectra from common tissue features such as stroma or blood, but also to detect the signatures of tumour sub-variants. As shown, their spectroscopic signals can change dramatically as a consequence of differentiation. Example cases are discussed and compared with histological evaluations.

A decade (2004 – 2014) of FTIR prostate cancer spectroscopy studies: An overview of recent advancements

“…In similar research to Gazi et al [22] and Baker et al [62], Baker et al [25]. also successfully used PCA-LDA to discriminate prostate cancer tissue in 3-band Gleason score (GS) criteria, which divided specimens into groups corresponding to GS < 7 for less aggressive, GS = 7 for intermediate aggressiveness, and GS > 7 for the most likely to progress, and also used the clinical stage taken from the TNM (tumour/node/metastases) classification system.…”

“…area in this manner to establish proof of principle. This goal has now been achieved, with the data currently presented clearly showing that FTIR-based methods can identify and discriminate between different types of prostate cancer [62].…”

“…One of the limitations of the Baker et al [62] study and the study by Gazi et al [22] is that the Gleason grading system was used as the reference standard for the development of the diagnostic algorithms. This methodology is inevitably flawed, as it will tend to incorporate problems inherent in the Gleason system into the new system.…”

“…Essentially, a PCA-LDA model is built for each PC up to a maximum number of m PCs. The optimum number of PCs is the one that provides maximal group separation and correct identification of classes [22,39,52,62]. PCA-LDA permits the construction of a predictive model that can be used for multi group data classification and dimensionality reduction for a given data set.…”

Assessing the challenges of Fourier transform infrared spectroscopic analysis of blood serum

“…The imaging analysis was pre-processed as previously described [24]. The processing was performed in order to demonstrate whether localised Figure 2 Amicon ¾ Ultra-0.5 centrifugal filter column protocol regions of similar molecular chemistry could be identified after removing sample thickness as an immediate factor (as explained in the results and discussion, this is not completely possible if saturation occurs).…”