Undetectability of oral tongue cancer on magnetic resonance imaging; clinical significance as a predictor to avoid unnecessary elective neck dissection in node negative patients

Abstract

Objectives: We aimed to investigate the relationship between MR imaging detectability and its pathological depth of invasion (DOI) of oral tongue cancer, as well as its usefulness to assess the necessity of elective neck dissection. Methods: We retrospectively reviewed early stage oral tongue cancer patients treated with radical surgery with clinically N0, between May 2009 and February 2016. Collected data include age, sex, pathological DOI, DOI on MRI, locoregional control rate, disease-free survival rate, and overall survival rate. These data were statistically compared between the detectable lesion (DL) group and undetectable lesion (UL) group on MRI. Interobserver agreement in evaluation of detectability of the oral tongue cancer was assessed by k statistics. Results: Total of 53 patients were studied, and 28 were DLs and 25 ULs. Pathological DOI in UL was significantly smaller than that of DL (average 1.7 vs 4.6 mm, p < 0.001). Cutoff value between UL group and DL group was 3.5 mm (sensitivity 96 %, specificity 75 %). 96 % of ULs had pathological DOI smaller than 4 mm, the recommended cutoff value for neck dissection. There was no significant difference in locoregional control rate (p = 0.24), disease-free survival rate (p = 0.24) or overall survival rate (p = 0.92). Interobserver agreement in evaluation of detectability on MRI was very good (k-value = 0.89, p < 0.001). conclusions: When oral tongue cancer is not detected on MRI, it indicates pathological DOI being smaller than 4 mm, which may imply that elective neck dissection is unnecessary.

Assessing the magnetic resonance imaging in determining the depth of invasion of tongue cancer

“…In a study of 53 tongue cancers with P‐DOI ranging from 0.5 to 8 mm, the difference between MR‐DOI and P‐DOI varied from 2.6 to 3.2 mm dependent on MRI sequences (Baba et al, 2019a). In another study only concerning to T2N0 tongue cancer patients, it resulted that the MR‐DOI overestimated P‐DOI by 2–3 mm (Murakami et al., 2019).…”

A comparative study between CT, MRI, and intraoral US for the evaluation of the depth of invasion in early stage (T1/T2) tongue squamous cell carcinoma

“…Although the UICC and AJCC state that ultrasonography is not suitable for the evaluation of primary lesions [9], some studies have evaluated primary lesions with intraoral ultrasonography (US) and have shown a strong correlation with histopathological thickness or DOI [10][11][12][13]. To date, several reports have been made on CT, MRI, and US preoperative radiological DOI evaluations, but there is no report of a study where these were all performed in a single institution [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. Therefore, this study was aimed to investigate the accuracy of preoperative radiological DOI measurement with CT, MRI, and US in the same target group based on histopathologically measured DOI for T1 and T2 tongue cancers, where a diagnosis of DOI around 5 mm is an important diagnostic finding and examine the effectiveness of each imaging modalities with retrospective approach.…”

Research on neck dissection for oral squamous-cell carcinoma: a bibliometric analysis

“… 36 With regard to the implementation of END, Akira Baba et al reported that oral tongue cancer undetectable on magnetic resonance imaging (MRI) indicated a high possibility of pathological DOI smaller than 4 mm, which can be used as a criterion to avoid unnecessary END in node-negative patients. 37 Nevertheless, MRI evidence of invasion to the styloglossus and hyoglossus muscles corresponds to a DOI greater than 4 mm, which can be a criterion for the advisability of END. 38 …”