Real time near-infrared Raman spectroscopy for the diagnosis of nasopharyngeal cancer

Abstract

Near-infrared (NIR) Raman spectroscopy has been investigated as a tool to differentiate nasopharyngeal cancer (NPC) from normal nasopharyngeal tissue in an ex-vivo setting. Recently, we have miniaturized the fiber-optic Raman probe to investigate its utility in real time in-vivo surveillance of NPC patients. A posterior probability model using partial linear square (PLS) mathematical technique was constructed to verify the sensitivity and specificity of Raman spectroscopy in diagnosing NPC from post-irradiated and normal tissue using a diagnostic algorithm from three significant latent variables. NIR-Raman signals of 135 sites were measured from 79 patients with either newly diagnosed NPC (N = 12), post irradiated nasopharynx (N = 37) and normal nasopharynx (N = 30). The mean Raman spectra peaks identified differences at several Raman peaks at 853 cm−1, 940 cm−1, 1078 cm−1, 1335 cm−1, 1554 cm−1, 2885 cm−1 and 2940 cm−1 in the three different nasopharyngeal conditions. The sensitivity and specificity of distinguishing Raman signatures among normal nasopharynx versus NPC and post-irradiated nasopharynx versus NPC were 91% and 95%; and 77% and 96% respectively. Real time near-infrared Raman spectroscopy has a high specificity in distinguishing malignant from normal nasopharyngeal tissue in vivo, and may be investigated as a novel non-invasive surveillance tool in patients with nasopharyngeal cancer.

Challenges in application of Raman spectroscopy to biology and materials

“…A specicity of $96% was observed in distinguishing normal, cancerous and post-radiation patients. 90 Almond et al utilised Raman spectroscopy and translated it into an endoscopic tool for the early detection of dysplasia in patients suffering from Barret's oesophagus. A high-grade dysplasia (HGD) oen results into oesophageal malignancy.…”

“…A specificity of ∼96% was observed in distinguishing normal, cancerous and post-radiation patients. 90 …”

Raman-Enhanced Spectroscopy Distinguishes Anal Squamous Intraepithelial Lesions in Human Immunodeficiency Virus-Serodiscordant Couples

“…50 The development of probes coupled with Raman systems has been proposed for a variety of epithelial cell cancers. [51][52][53][54] These systems described in the literature are all custom built using commercially available Raman lasers, probes, and charge-coupled devices. These probes open the possibility of cancer detection but are limited to only spectral analysis.…”

Raman Spectroscopy Applied to Health Sciences

“…Analysis of 2124 Raman spectra of 60 patients during endoscopy showed sensitivity and specificity above 90% for the identification of laryngeal cancer when combined fingerprint and high-wavenumber spectra [32]. Recently, Ming et al [33] performed a pilot study in 79 patients with and without nasopharyngeal cancer and in postirradiated patients. They detect a specific signature for each one of the three cohorts, which may indicate that Raman could not only be used for diagnostic purposes but also for surveillance in post-treated patients.…”

“…They detect a specific signature for each one of the three cohorts, which may indicate that Raman could not only be used for diagnostic purposes but also for surveillance in post-treated patients. Furthermore, the authors used a probe with only 1.8 mm, which is the smallest probe used in Raman diagnostics and is more suitable to be used in clinical endoscopies [33].…”