ORIGINAL ARTICLE
Year : 2022 | Volume
: 10 | Issue : 3 | Page : 80--86
Are magnetic resonance imaging findings adequate for differentiating head-and-neck masses as malignant or benign?
Ali Ocak1, Binali Cakir2,
1 Department of Dentomaxillofacial Radiology, Erzincan Binali Yildirim University, Faculty of Dentistry, Erzincan, Turkey
2 Department of Dentomaxillofacial Radiology, Ataturk University, Faculty of Dentistry, Erzurum, Turkey
Correspondence Address:
Ali Ocak
Department of Dentomaxillofacial Radiology, Erzincan Binali Yildirim University, Faculty of Dentistry, Erzincan
Turkey
Abstract
Purpose: This work aims to determine the magnetic resonance imaging (MRI) findings of the masses seen in the head-and-neck region and the effectiveness of the MRI in separation of malignant from benign head-and-neck masses through histopathological data. Materials and Methods: This retrospective study was conducted on 86 patients who were referred with prediagnosed as mass in oral, head and neck regions for evaluation with magnetic resonance imaging. MRI images were analyzed according to homogeneity and signal intensity in T1- and T2-weighted images, contrast enhancement pattern, peripheral edge characteristic of the lesion, invasion condition, presence of cystic/necrotic content, and presence of bone involvement of head-and-neck masses. Results: The MRI features of benign and malignant head and neck masses in which signal intensity on T1-weighted MRI images, signal homogeneity on T2-weighted MRI images, contrast enhancement pattern, edge feature and presence of invasion showed a statistically significant difference to determine benignity and malignancy. However, the signal homogeneity in T1-weighted images, signal intensity in T2-weighted images, presence of cystic/necrotic content, and bone involvement did not reveal a statistically significant difference. Conclusions: Overall, our findings were consistent with the literature data. As a result of our study, we recommend that certain MRI features of head-and-neck masses (signal intensity in T1-weighted images, signal homogeneity in T2-weighted images, contrast enhancement pattern, edge feature, and presence of invasion) can be used to differentiate between benign and malignant masses.
How to cite this article:
Ocak A, Cakir B. Are magnetic resonance imaging findings adequate for differentiating head-and-neck masses as malignant or benign?.J Oral Maxillofac Radiol 2022;10:80-86
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How to cite this URL:
Ocak A, Cakir B. Are magnetic resonance imaging findings adequate for differentiating head-and-neck masses as malignant or benign?. J Oral Maxillofac Radiol [serial online] 2022 [cited 2023 Apr 2 ];10:80-86
Available from: https://www.joomr.org/text.asp?2022/10/3/80/366163 |
Full Text
Introduction
Head-and-neck masses have importance in this region diseases and especially cancers of this region have been shown as the sixth most common cancer.[1] Head-and-neck region contains a large number of anatomical structures in a small area, also this region is one of the most complex parts of the body where clinically limited information is provided.[2]
The aim of this study is to evaluate conventional magnetic resonance imaging (MRI) with and without contrast enhancement features (homogeneity and signal intensity in T1- and T2-weighted images, contrast enhancement pattern, peripheral edge characteristic of the lesion, invasion condition presence of cystic/necrotic areas, and presence of bone involvement of head-and-neck masses).
Materials And Methods
This retrospective study was conducted on 86 patients who were referred with prediagnosed as mass in oral, head and neck regions for evaluation with magnetic resonance imaging to the department of diagnostic radiology in our university hospital. Histopathological diagnosis of 47 of the lesions was made by incisional biopsy while 48 lesions were detected with materials obtained as a result of surgical excision. Contrast-enhanced and conventional MRI examinations of the cases had been performed in our study with 1.5 Tesla Siemens Magnetom Avanto or 3 Tesla Siemens Magnetom Skyra (Siemens Medical Systems, Erlangen, Germany) MRI devices. For this study, ethics approval was received by the institutional ethical committee.
Statistical analyzes were performed using the SPSS (Statistical Package for the Social Sciences) software, version 20.0 for Windows (SPSS Inc, Chicago, IL) computer package program. Statistically, whether there is a significant difference or not of MRI features among malignant and benign masses was evaluated using “Chi-square test (χ2)” and descriptive statistics (frequency and average). P < 0.05 was regarded as indicating a significant difference.
Evaluation of images
Images were evaluated considering each lesion; signal homogeneity and intensity on T1- and T2-weighted MRI images, contrast enhancement pattern, edge feature, invasion status, presence of septation and lobulation, presence of cystic-necrotic content and bone involvement.
Signal intensity was examined in three groups at each MRI sequence: lower signal intensity (hypointense) than adjacent healthy muscle tissue, equal signal intensity (isointense) to the muscle, and higher signal intensity (hyperintense) to the muscle.
Signal homogeneity; if more than 20% of the volume of corresponding lesion shows different signal intensity on for each T1-weighted and T2-weighted MRI images was classified as heterogeneous otherwise homogeneous.
Results
As a result of radiological and histopathological evaluations, these head-and-neck masses; lymphoma (4), squamous cell carcinoma (21), adenocarcinoma (1), adenoid cystic carcinoma (2), mucoepidermoid carcinoma (1), salivary gland ductal carcinoma (1), acinic cell carcinoma (1), thyroid papillary carcinoma (6), carcinoma metastasis (14), chondrosarcoma (1), malignant mixed tumor (2), nonkeratinizing nasopharyngeal carcinoma (11), keratinized squamous cell carcinoma (3), pleomorphic adenoma (6), Warthin tumor (2), laryngocele (1), giant cell granuloma (1), necrotizing granulomatous lymphadenitis (3), branchial cleft cyst (3), nasolabial cyst (2), thyroglossal duct cyst (1), chronic sialadenitis (2), antrochoanal polyp (1), inflammatory granulation tissue (1), dentigerous cyst (1), Thornwaldt cyst (6), paraganglioma (2), parathyroid adenoma (1) and parathyroid cyst (1) were determined.
In our study, we examined a total of 102 head-and-neck masses which were detected in 43 male and 43 female patients. Patients' ages were varying from 10 to 79 (mean: 44.10 ± 19.56). Thirty-four (33.3%) of 102 masses were benign and 68 (67.7%) were malignant. Pleomorphic adenoma (n = 6; 17.6%) and Thornwaldt cyst (n = 6; 17.6%) were the most common types of benign masses, and also, squamous cell carcinoma was the most common malignant mass (n = 21; 30.9%).
In our study, when the relationship of head-and-neck masses with gender is examined, a statistically significant difference was found between men and women (P < 0.05). According to our study group, malignant head-and-neck masses are more common in men while benign masses are more common in women.
When the relationship between head and neck masses with age were examined; a statistically significant difference was found between benign and malignant masses. The benign masses are detected as a higher rate in young (10–30 years old) and young-adult (31–50 years old) groups while the malignant masses were observed a higher rate in the adult patient group (51–79 years) [Figure 1].{Figure 1}
A statistically significant difference was found between benign and malignant head-and-neck masses and signal intensity (hypointense, isointense, and hyperintense) in T1-weighted images (P < 0.05). According to this, 85.7% (n = 6) of the masses were benign which showed a hyperintense signal feature in T1-weighted images, while 80.0% (n = 36) of the masses that show isointense signaling with adjacent muscle tissue were malignant [Table 1].{Table 1}
There was no statistically significant difference in relationship between benign and malignant head-and-neck masses and signal homogeneity (homogeneous and heterogeneous) in T1-weighted images (P > 0.05).
When the relationship between head and neck masses with the signal intensity on T2-weighted MRI images were examined; almost all of the masses (n = 98) had a hyperintense signal intensity that could not be evaluated statistically.
A statistically significant difference was found between benign and malignant head-and-neck masses and signal homogeneity in T2-weighted images (P < 0.05).
When the relationship between the head-and-neck masses and the contrast enhancement pattern in the fat-suppressed contrast-enhanced T1-weighted images is examined, no contrast enhancement was observed in the 8 (23.5%) benign and 2 (2.9%) malignant masses.
A statistically significant difference was found between 26 (76.4%) benign and 66 (97.1%) malignant masses which showed different contrast enhancement pattern (P < 0.05) [Table 2].{Table 2}
When the relationship between head-and-neck masses and edge features is examined, a statistically significant difference was found between benign and malignant masses (P < 0.05). According to this, benign masses have well-defined, regular margins while malignant masses have irregular margins [Table 3] and [Figure 2].{Table 3}{Figure 2}
When the relationship between head-and-neck masses and invasion into adjacent tissues is examined, a statistically significant difference was found between benign and malignant masses (P < 0.05). According to this, it was determined that benign masses did not invade [Table 4].{Table 4}
When the relationship between head-and-neck masses and the presence of septation and lobulation is examined, septation and lobulation were detected in 3 (4.4%) malignant masses and 3 (8.8%) benign masses. The effect of the presence of septation and lobular contours in the differentiation of benign and malignant head-and-neck masses could not be statistically evaluated due to insufficient sample size.
When the relationship between malignant and solid benign head-and-neck masses and cystic/necrotic content status is examined, there was no statistically significant difference between benign and malignant masses (P > 0.05). Accordingly, cystic or necrotic contents were not related to benign or malignant features of neck masses [Table 5] and [Figure 3].{Table 5}{Figure 3}
When the relationship between head-and-neck masses and the presence of bone involvement is examined, there was no statistically significant difference between benign and malignant masses (P > 0.05). According to this, bone involvement in head-and-neck masses is not related to being benign or malignant.
Discussion
MRI has been shown to be superior to ultrasonography and computed tomography in determining the morphological features of tumoral tissues such as size, spread, and relationship with vascular structures.[3] Furthermore, muscle, tendon, cartilage, disc, meniscus, synovium, nerve, vascular, fat, fluid, cortical bone, and bone marrow structures can be distinguished by MRI. Although unenhanced MRI is an important diagnostic tool in the evaluation of soft tissue masses, spread of lesions, staging of tumors, biopsy planning, preoperative chemotherapy response, and recurrence-residual tissue can be detected with contrast-enhanced MRI.[4]
In our study, when we look at the frequency of head-and-neck masses according to their malignant and benign characteristics, it was determined that 33.3% of them were benign and 66.7% of them were malignant masses. When the relationship of the masses with gender is evaluated, similar to the literature, malignant masses in the head-and-neck region were found to be more common in men (58.8%), and benign masses were more common in women (67.6%).[5],[6]
There are very different results have been obtained by researchers that using the MRI features (signal homogeneity and intensity on T1- and T2-weighted MRI images, contrast enhancement pattern, margin feature, invasion status, presence of septation and lobulation, presence of cystic/necrotic content and bone involvement) of soft tissue masses to differentiate benign and malignant.[7],[8],[9],[10],[11],[12],[13] The intensity and homogeneity of the magnetic resonance signals in different pulse sequences are widely used in the detection of malignancy of the masses.[14] Weatherall et al. stated that high signal intensity in T2-weighted images is a sensitive parameter in the detection of malignant masses but has unacceptably low specificity.[15] Hermann et al. obtained a hypointense appearance in 17% and hyperintense appearance in 58% of benign tumors on T1-weighted images and also a hyperintense appearance in 85% of benign tumors on T2-weighted images. They found that malignant tumors exhibited hyperintense signals in 40% of T1-weighted images and in all T2-weighted images.[16]
In our study, similar to the literature, we obtained hypointense signal intensity in 55.8% of benign lesions and 48.4% of malignant lesions in T1-weighted images. On T2-weighted images, we found that 97% of benign lesions and 95.5% of malignant lesions showed a hyperintense signal feature. In our study, a statistically significant difference was found between the isointense signal feature with adjacent muscle tissue and the condition of the masses being malignant (80%) on T1-weighted images and also between the hyperintense signal feature and the condition of the masses being benign (85.7%) on T1-weighted images (P = 0.002). When compared with the literature, this difference may be due to the number of the population, race, technique used, and the differences in the stages of the masses.[17],[18]
As a general acceptance, 90% of malignant lesions are heterogeneous, although small lesions tend to be more homogeneous. The absence of heterogeneity is accepted as a reliable negative predictive indicator for malignancy.[18]
Pang et al. reported that 68% of benign lesions showed a homogeneous signal intensity on T1-weighted images and 63% on T2-weighted images, while 39% of malignant lesions showed a homogeneous signal intensity on T1-weighted images and 11% on T2-weighted images, and there was no statistical significance difference between both groups.[19] Totty et al. suggested that the majority of benign and malignant masses exhibit heterogeneous signal intensity and homogeneity differences do not help in the differentiation of benign from malignant.[20]
Soler et al., in their study on 65 soft tissue masses, reported that 42 masses showed homogeneous signal intensity on T1-weighted images and 43 masses of heterogeneous signal intensity on T2-weighted images. These researchers also found that most of the benign tumors and nontumor lesions were homogeneous in T1-weighted images (benign tumors, 64.2%; nontumor lesions, 73.9%) and 67.8% of benign tumors and 56.5% of nontumor lesions exhibit heterogeneous signal intensity on T2-weighted images. They stated that malignant tumors showed heterogeneous signal intensity at a rate of 50% on T1-weighted images and 78.5% on T2-weighted images, and there was no statistically significant difference between all three groups.[21]
In our study, 67.6% of benign masses and 57.8% of malignant masses exhibited a homogeneous appearance on T1-weighted images. The relationship between homogeneity and benign and malignant masses in T1-weighted images was no statistically significant difference (P > 0.05). However, 61.7% of benign masses exhibited homogeneous and 67.6% of malignant masses showed heterogeneous signal intensity in T2-weighted images. A statistically significant difference was found between heterogeneity and malignancy in T2-weighted images (P = 0.005). This relationship is consistent with the literature.[10],[13],[14],[19],[22]
Some researchers think that the presence of intralesional septa is useful in the differentiation of benign and malignant.[23],[24] Hosono et al. have observed that liposarcomas generally show septation thicker than 2 mm and significantly enhancing while benign lipomas contain thinner septa.[25]
In our study, we could not statistically evaluate the effect of septation and lobular contour in the detection of malignant and benign masses due to insufficient sample size.
Bongartz et al. reported that aggressive sarcomas may be surrounded by pseudocapsules and that desmoid tumors in the benign class may invade neighboring tissues. These researchers concluded that the margin features (smooth/well circumscribed or irregular/poorly circumscribed) are not statistically significant in distinguishing between benign and malignant soft tissue masses in MRI.[26]
When we evaluate the margin properties of head-and-neck masses in MRI in our study, we found that 68.9% of well-circumscribed lesions were benign and 94.7% of irregularly circumscribed lesions were malignant masses.
While invasion was not observed in adjacent tissues in any of the benign masses, invasion was observed in 47% of malignant masses. Accordingly, a statistically strong correlation was found between the benign-malign characteristics of head-and-neck masses, having irregular borders and showing invasion (P = 0.001). Masses with irregular borders and invasion were found to be malignant. This relationship is consistent with the literature.[10],[20],[21],[26] The use of contrast material in MRI has an important place in the evaluation of pathologies belonging to the head and neck and other structures of the body. In addition, the information about between tumor, muscle, edematous tissues, solid, cystic-necrotic components of the lesions and their spread can be obtained with contrast-enhanced MRI.[17],[27] Benign and malignant tumors can show very different degrees of enhancement after contrast material injection in MRI. Although little vascularization and therefore low contrast were observed in some malignant lesions, increased vascularization and high contrast can be observed in some benign lesions.[14],[28] Erlemann et al. reported that the enhancement ratio may be useful in the differentiation of benign and malignant soft tissue lesions.[29] When we evaluate the contrast enhancement pattern of head-and-neck masses in MRI in our study, heterogeneous enhancement was observed in 80% of the malignant masses which showed enhancement. A statistically significant relationship was found between head-and-neck malignant masses (80%) and heterogeneous enhancement in MRI (P = 0.001). This situation is consistent with the literature.[14],[29] Chen et al., in their study on 118 masses (56 – benign and 62 – malignant), found that cystic-necrotic content was present in 9% of benign masses and 45.1% of malignant masses. They found the positive predictive value of necrosis observed in MRI to detect malignancy as 84.8% and its specificity as 90.9%.[17] We found that 61.7% (n = 42) of malignant masses and 42.1% (n = 8) of benign masses in our study had a cystic-necrotic content. However, the relationship between cystic-necrotic content and malignancy was not statistically significant (P = 0.125). Compared with the literature, this difference may be due to the number of populations, race, and the differences in the stages of the masses.[13],[17]
When we evaluate the relationship between bone involvement and head-and-neck masses in our study, bone involvement was detected in 18.7% of all lesions. Three (8.8%) of the masses with bone involvement were benign and 16 (23.5%) were malignant. However, there was no relationship between bone involvement and malignancy (P = 0.072). In our study, the findings we obtained in terms of bone involvement in benign and malignant masses are compatible with the literature.[11],[14]
There are various studies in the literature investigating the characteristic features of benign and malignant masses with MRI and obtaining different results.[7],[8],[9],[10],[11],[12],[13],[14],[15],[16],[17],[18] De Schepper et al., in the detection of malignancy in their study, concluded that the margin feature of the lesion, its homogeneity on T2-weighted images, its intensity on T1-weighted images, degree of contrast, and pattern are not statistically significant, but low signal intensity in T2-weighted images, heterogeneous intensity on T1-weighted images, and lesion diameter >33 mm have high sensitivity in detecting malignancy.[30]
Berquist et al. evaluated MRI appearance features (volume, edge features, signal intensity in T1- and T2-weighted sequences, bone involvement, necrosis, and hemorrhage) of the 95 soft tissue masses (45 – malignant and 50 – benign) and concluded that the separation of benign or malignant masses could be detected by MRI at a rate of 90%.[10] Crim et al. have reported that malignant lesions may exhibit a well-circumscribed and homogeneous appearance on MRI; therefore, it is not reliable to distinguish benign from malignant with these parameters.[11] In some studies other than these, it has been suggested that the MRI appearance of soft tissue masses is nonspecific.[7],[9],[20],[31]
Sundaram et al. stated that there is no reliable criterion for the differentiation of benign and malignant tumors with MRI after examined a total of 53 soft tissue masses (30 – benign and 23 –malignant).[9] Kransdorf et al. showed that specific diagnosis could be made only in 27 lesions (10 – lipomas, 8 – hemangiomas, 6 – pigmented villonodular synovitis, 2 – hematoma, and 1 – arteriovenous malformation) with specific MRI features of 112 lesions (85 – benign and 27 – malignant).[31]
Conclusions
In this study, MRI features (homogeneity and signal intensity in T1- and T2-weighted images, contrast enhancement pattern, margin feature, invasion status, presence of septation and lobulation, presence of cystic/necrotic content, and bone involvement) of 102 head-and-neck masses were determined and these findings were compared with the literature data.
Overall, our findings were consistent with the literature data. As a result of our study, we recommend that certain MRI features of head-and-neck masses (signal intensity in T1-weighted images, signal homogeneity in T2-weighted images, contrast enhancement pattern, margin feature, and presence of invasion) can be used to differentiate between benign and malignant masses.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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