Raman exfoliative cytology for oral precancer diagnosis

Abstract

Oral premalignant lesions (OPLs) such as leukoplakia, erythroplakia, and oral submucous fibrosis, often precede oral cancer. Screening and management of these premalignant conditions can improve prognosis. Raman spectroscopy has previously demonstrated potential in the diagnosis of oral premalignant conditions (in vivo), detected viral infection, and identified cancer in both oral and cervical exfoliated cells (ex vivo). The potential of Raman exfoliative cytology (REC) in identifying premalignant conditions was investigated. Oral exfoliated samples were collected from healthy volunteers (n=20), healthy volunteers with tobacco habits (n=20), and oral premalignant conditions (n=27, OPL) using Cytobrush. Spectra were acquired using Raman microprobe. Spectral acquisition parameters were: λex: 785 nm, laser power: 40 mW, acquisition time: 15 s, and average: 3. Postspectral acquisition, cell pellet was subjected to Pap staining. Multivariate analysis was carried out using principal component analysis and principal component-linear discriminant analysis using both spectra- and patient-wise approaches in three- and two-group models. OPLs could be identified with ∼77% (spectra-wise) and ∼70% (patient-wise) sensitivity in the three-group model while with 86% (spectra-wise) and 83% (patient-wise) in the two-group model. Use of histopathologically confirmed premalignant cases and better sampling devices may help in development of improved standard models and also enhance the sensitivity of the method. Future longitudinal studies can help validate potential of REC in screening and monitoring high-risk populations and prognosis prediction of premalignant lesions.

Relationship between oral candidiasis and users of dental prostheses

“…The clinical diagnosis is what differs this type from the others found. However, through the smear on the lamina, filamentous (hyphae) and spore forms were observed in three smears, typical of pseudomembranous candidiasis, corroborating with other authors 6,11 . This examination is recommended according to Schiboch et al 10 (2005) when pseudomembranous candidiasis is suspected and it is possible to visualize under the microscope, after smearing and staining of the slides, fungi in yeast and filamentous forms with epithelial cells.…”

“…The diagnosis of oral candidiasis was based on clinical signs and symptoms, aided by microscopic examination of the smear. Patients who presented lesions, independently of the laboratory report, were treated with nystatin, under the supervision of dental surgeons of the UBH, for having exclusive effect on Candida and absence of systemic effects [11][12][13] .…”

Raman exfoliative cytology for prognosis prediction in oral cancers: A proof of concept study

“…The clinical significance of contralateral normal misclassifications with tumor in predicting recurrences in oral cancer patients in vivo was recently demonstrated by Malik et al . In the present study, we have investigated the feasibility of detecting recurrences through Raman exfoliative cytology, after successfully differentiating normal, premalignant and malignant cells . Exfoliative cytology is associated with advantages such as minimally‐invasive sampling, possibility of multiple sampling and sample transportation to a centralized facility for analysis, and is a more practical approach for patient monitoring in low‐resource settings.…”

A pilot study for early detection of oral premalignant diseases using oral cytology and Raman micro‐spectroscopy: Assessment of confounding factors

“…Approximately 10 to 25 cells were recorded per slide, depending on the quality of the sample. Although a small voxel (~1 μm) is sampled each time, randomly sampling over multiple (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25) cells means that the distribution of samplings effectively represents the variability across the cellular region [28][29][30].…”

“…Combining information from molecular profiles with cytological techniques may overcome the limitations of cytology [11]. Previously, FTIR and Raman spectroscopy has shown potential to detect oral cancer and precancerous changes using exfoliated cells [20][21][22][23][24][25].…”