Assessment of squamous cell carcinoma of the floor of the mouth with magnetic resonance imaging

Akira Baba,Hiroya Ojiri,Takeshi Nomura,Ryo Kurokawa,Kazuhiko Hashimoto,Yoshiaki Ota,Koshi Ikeda,Koichi Masuda,Suzuki Taiki,Satoshi Matsushima,Hideomi Yamauchi,Satoru Ogane,Hirofumi Kuno,Masae Yamazaki

doi:10.1007/s11604-021-01161-1

Abstract

PurposeWe aimed to use magnetic resonance imaging (MRI) to determine the relationship between the pathological depth of invasion (DOI), undetectability, and tumor thickness of squamous cell carcinoma of the floor of the mouth.Materials and methodsWe retrospectively evaluated the relationship between pathological DOI and MRI detectability, as well as the relationship between pathological DOI and tumor thickness on coronal fat-suppressed contrast-enhanced T1-weighted imaging or coronal T2-weighted imaging.ResultsWe analyzed 30 patients with squamous cell carcinoma of the floor of the mouth; MRI revealed that the pathological DOI of the 11 undetectable lesions (median 2 mm) was smaller than that of the 19 detectable lesions (median 14 mm) (p < 0.001), and the cut-off value was 3 mm (sensitivity, 0.84; specificity, 0.91; area under the curve, 0.89). Tumor thickness on coronal fat-suppressed contrast-enhanced T1-weighted imaging was assessed in all 19 detectable lesions; however, tumor thickness on coronal T2-weighted imaging could not be assessed in eight cases. Tumor thickness on coronal fat-suppressed contrast-enhanced T1-weighted imaging was found to be significantly associated with the pathological DOI.ConclusionsUndetectability on MRI indicates superficial lesions with a pathological DOI value that is less than 3 mm. In detectable lesions, tumor thickness on coronal fat-suppressed contrast-enhanced T1-weighted imaging is associated with pathological DOI.

Highlights

Squamous cell carcinoma is the most common oral cancer, with the tongue being the most commonly affected site, followed by the mandibular gingiva and the floor of the mouth [1]
In the 8th edition of the Cancer Staging Manual by the American Joint Committee on Cancer (AJCC), depth of invasion (DOI) has been added to the T-staging criteria for oral cancer [2]. This is because pathological DOI is strongly associated with cervical lymph node metastasis, which is the most influential negative prognostic
The difference between tumor thickness on contrast-enhanced T1-weighted imaging (CET1WI) and pathological DOI with 1.5 T magnetic resonance imaging (MRI) in 13 cases was 3.3 mm, and that with 3 T MRI in 7 cases was 3.9 mm; there was no significant difference between the two MRI modalities (p = 0.588)

Summary

Introduction

Squamous cell carcinoma is the most common oral cancer, with the tongue being the most commonly affected site, followed by the mandibular gingiva and the floor of the mouth [1]. In the 8th edition of the Cancer Staging Manual by the American Joint Committee on Cancer (AJCC), depth of invasion (DOI) has been added to the T-staging criteria for oral cancer [2]. This is because pathological DOI is strongly associated with cervical lymph node metastasis, which is the most influential negative prognostic. Japanese Journal of Radiology for oral cancers, including floor of the mouth cancer [3, 4]. The cancer staging manual does not describe how to estimate the pathological DOI before treatment by radiological assessment [2]. It is important to standardize the pre-treatment estimation of DOI by imaging

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