CT texture analysis of tonsil cancer: Discrimination from normal palatine tonsils

Abstract

The purposes of the study were to determine whether there are differences in texture analysis parameters between tonsil cancers and normal tonsils, and to correlate texture analysis with 18F-FDG PET/CT to investigate the relationship between texture analysis and metabolic parameters. Sixty-four patients with squamous cell carcinoma of the palatine tonsil were included. A ROI was drawn, including all slices, to involve the entire tumor. The contralateral normal tonsil was used for comparison with the tumors. Texture analysis parameters, mean, standard deviation (SD), entropy, mean positive pixels, skewness, and kurtosis were obtained using commercially available software. Parameters were compared between the tumor and the normal palatine tonsils. Comparisons were also performed among early tonsil cancer, advanced tonsil cancer, and normal tonsils. An ROC curve analysis was performed to assess discrimination of tumor from normal tonsils. Correlation between texture analysis and 18F-FDG PET/CT was performed. Compared to normal tonsils, the tumors showed a significantly lower mean, higher SD, higher entropy, lower skewness, and higher kurtosis on most filters (p<0.001). On comparisons among normal tonsils, early cancers, and advanced tonsil cancers, SD and entropy showed significantly higher values on all filters (p<0.001) between early cancers and normal tonsils. The AUC from the ROC analysis was 0.91, obtained from the entropy. A mild correlation was shown between texture parameters and metabolic parameters. The texture analysis parameters, especially entropy, showed significant differences in contrast-enhanced CT results between tumor and normal tonsils, and between early tonsil cancers and normal tonsils. Texture analysis can be useful as an adjunctive tool for the diagnosis of tonsil cancers.

Role of Texture Analysis in Oropharyngeal Carcinoma: A Systematic Review of the Literature

“…Among the 26 selected papers (Table 2), the largest number were from the USA [41][42][43][44][45][46][47][48][49][50][51] and Korea [52][53][54][55], whereas the rest of them were from Switzerland [56,57], the Netherlands [58,59], Italy [19,60], Canada [61], Japan [62,63], Taiwan [64,65] and China [45]. Fourteen articles [19,41,[43][44][45][46][47]49,52,53,55,57,58,62] had the oropharynx as the anatomic area of interest and seven articles [42,48,54,56,[59][60][61] analysed the head and neck district with sections dedicated t...…”

“…Fourteen articles [19,41,[43][44][45][46][47]49,52,53,55,57,58,62] had the oropharynx as the anatomic area of interest and seven articles [42,48,54,56,[59][60][61] analysed the head and neck district with sections dedicated to the oropharynx. Six, thirteen, and two articles, respectively, used MRI [53][54][55]58,59,61], CT [19,[41][42][43][44][45][46][47]52,56,57,60,62], and PET-CT [48,49] as imaging techniques on which texture analysis was performed (Table 3). Among the 26 studies, eleven of them used free software to extract textural data [19,44,[50][51][52]…”

“…Six, thirteen, and two articles, respectively, used MRI [53][54][55]58,59,61], CT [19,[41][42][43][44][45][46][47]52,56,57,60,62], and PET-CT [48,49] as imaging techniques on which texture analysis was performed (Table 3). Among the 26 studies, eleven of them used free software to extract textural data [19,44,[50][51][52][53][54][55]58,60,62,63]; five studies used licensed software [43,49,52,61,64], whereas the remaining ten papers used in house developed software not available to the public. Furthermore, ten studies focused on the distinction between HPV+ and HPV-neoplasms [19,[41][42][43][44]46,52,57,…”

“…While no specific textural trend could be identified, most studies found histogram features, entropy, and gray-level co-occurrence to be the features more frequently present in radiomic signatures correlated to HPV positivity. Six studies focused on the diagnosis of oropharyngeal neoplasms [49][50][51]54,55,62] developing different complex models that allowed to infer the nature of a lesion with varying levels of sensibility and specificity. However, no specific trend or cutoff emerged from the evaluation of the aforementioned studies.…”

“…The study conducted by Kim et al [49] aimed to look for a correlation between texture parameters in the differentiation between tonsillar cancer and normal tonsillar tissue and to correlate them with 18 F-FDG PET/CT, in order to investigate the relationship between texture analysis and metabolic parameters. Neoplastic tonsil is characterized by asymmetric enlargement with increased enhancement after contrast media intravenous injection.…”