The role of MRI scanning in the diagnosis of cervical lymphadenopathy

Diagnostic value of magnetic resonance imaging in cervical lymph node metastasis of oral squamous cell carcinoma

OBJECTIVE

The objective of this study was to investigate the correlation between magnetic resonance imaging (MRI) characteristics of cervical lymph nodes and the pathologically confirmed status of cervical lymph node metastasis (LNM) in oral squamous cell carcinoma (OSCC) and to provide imaging evaluation parameters for the clinical diagnosis of cervical lymph node status in OSCC.

STUDY DESIGN

In a retrospective analysis, 79 patients who were first pathologically diagnosed with OSCC were included. The MRI-derived imaging parameters of the cervical lymph nodes were evaluated and the pathological status of lymph nodes in neck dissection specimens was reviewed. The relationship between the imaging parameters and cervical LNM was analyzed.

RESULTS

The MRI-derived imaging parameters of 4419 lymph nodes were evaluated, and the pathological status of 2463 lymph nodes was reviewed. The MRI-derived shortest axial diameter (SAD) and unclear boundary of the cervical lymph node were significantly related to LNM. The cutoff value of SAD that enabled identification of LNM was 3.6 mm, and it was 4.2 and 4.1 mm for the prediction of overall survival and disease-specific survival, respectively.

CONCLUSIONS

The MRI-derived parameters SAD and unclear boundary of the cervical lymph node correlated with LNM in OSCC. MRI-derived SAD larger than 3 mm warrants simultaneous neck dissection at initial surgery.

Computed tomography versus magnetic resonance imaging for diagnosing cervical lymph node metastasis of head and neck cancer: a systematic review and meta-analysis

Computed tomography (CT) and magnetic resonance imaging (MRI) are common imaging methods to detect cervical lymph node metastasis of head and neck cancer. We aimed to assess the diagnostic efficacy of CT and MRI in detecting cervical lymph node metastasis, and to establish unified diagnostic criteria via systematic review and meta-analysis. A systematic literature search in five databases until January 2014 was carried out. All retrieved studies were reviewed and eligible studies were qualitatively summarized. Besides pooling the sensitivity (SEN) and specificity (SPE) data of CT and MRI, summary receiver operating characteristic curves were generated. A total of 63 studies including 3,029 participants were involved. The pooled results of meta-analysis showed that CT had a higher SEN (0.77 [95% confidence interval {CI} 0.73–0.87]) than MRI (0.72 [95% CI 0.70–0.74]) when node was considered as unit of analysis (P<0.05); MRI had a higher SPE (0.81 [95% CI 0.80–0.82]) than CT (0.72 [95% CI 0.69–0.74]) when neck level was considered as unit of analysis (P<0.05) and MRI had a higher area under concentration-time curve than CT when the patient was considered as unit of analysis (P<0.05). With regards to diagnostic criteria, for MRI, the results showed that the minimal axial diameter of 10 mm could be considered as the best size criterion, compared to 12 mm for CT. Overall, MRI conferred significantly higher SPE while CT demonstrated higher SEN. The diagnostic criteria for MRI and CT on size of metastatic lymph nodes were suggested as 10 and 12 mm, respectively.

Value of magnetic resonance imaging for nodal staging in patients with head and neck squamous cell carcinoma: a meta-analysis

OBJECTIVES

To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) in detecting lymph node metastases in patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

MEDLINE, EMBASE, the CBM disc databases, and other databases were searched for relevant original articles published between January 1990 and January 2011. Meta-analysis methods were used to pool sensitivity and specificity and to construct summary receiver-operating characteristic, and to calculate positive and negative likelihood ratios (LR+ and LR-). We also compared the performance of MRI with other diagnostic methods (positron emission tomography, computed tomography, and ultrasound) by analyzing studies that had also used these diagnostic methods on the same patients.

RESULTS

Across 16 studies, there was no evidence of publication bias (P = .15). Sensitivity and specificity of MRI for cervical lymph node status in patients with HNSCC across all studies were 76% (95% CI: 70%-82%) and 86% (95% CI: 73%-93%), respectively. Overall, Positive likelihood ratios was 5.47 (95% CI: 2.69-11.11) and positive negative likelihood ratios was 0.28 (95% CI: 0.21-0.36), respectively. The comparison of MRI performance with that of other diagnostic tools (positron emission tomography, computed tomography, and ultrasound) suggested no major differences against any of these methods. The Subgroup by using diffusion-weighted imaging had higher pooled sensitivity (0.86, 95% CI 0.78-0.92) than the subgroup without diffusion-weighted imaging.

CONCLUSION

MRI has good diagnostic performance in the overall pretreatment evaluation of node staging with HNSCC. A limited number of small studies suggest DWI is superior to conventional imaging for nodal staging of HNSCC.

Early MR lymphography with gadofluorine M in rabbits

PURPOSE

To investigate the dose and time dependency of gadofluorine M for lymph node imaging and the detection of lymph node metastases in an animal model and to compare gadofluorine M with Gadomer (both, Schering, Berlin, Germany) for lymph node enhancement.

MATERIALS AND METHODS

Enhancement of popliteal and iliac lymph nodes was studied in VX2 tumor-bearing rabbits before injection and at 5-120 minutes and 24 hours after intravenous bolus injection of 0.025, 0.05, and 0.1 mmol gadolinium per kilogram of body weight gadofluorine M (six rabbits) or 0.5 mmol/kg Gadomer (eight rabbits). Effects of treatment and time point at enhancement were evaluated with repeated measures analysis of variance. Means were separated with all-pairs comparison with Tukey-Kramer adjustment. After 1.5-T magnetic resonance (MR) imaging, lymph nodes were removed, and prepared sections were stained with hematoxylin-eosin for microscopic examination.

RESULTS

MR images in VX2 tumor-bearing rabbits revealed rapid and strong signal intensity increase in the functional lymph node tissue by 15 minutes after intravenous injection of gadofluorine M. Maximum enhancement of 165%-309% was observed 60-90 minutes after injection (enhancement with 0.05 and 0.1 mmol/kg significantly different from that with 0.025 mmol/kg, P < or =.05). Metastatic tissue showed only slight enhancement at early time points, resulting in high-contrast differentiation between functional and metastatic tissue. Intravenous injection of the blood-pool agent Gadomer induced only short and inhomogeneous lymph node enhancement (enhancement significantly lower [P < or =.05] than that with gadofluorine M).

CONCLUSION

Findings in the study showed that gadofluorine M produces rapid lymph node accumulation. Diagnosis of lymph node metastases was shown with intravenous injection of gadofluorine M with a minimum effective diagnostic dose of 0.025 mmol/kg.

Diagnosis and management of uncommon cutaneous cancers

Uncommon types of cutaneous cancers are mainly cited in the literature as case reports and their etiology, pathogenesis and prognosis have to be surmised because of their rarity. Within this group exist the rare and also the unusual, for instance a relatively common carcinoma arising in a strange circumstance. Initial management of such tumors involves taking a history and performing a thorough examination, allowing a diagnosis to be made. These tend to follow one of three patterns: the lesion is confidently recognized; the lesion is unknown but a likely diagnosis can be made and; the lesion is unknown. It is within the latter two groupings that the uncommon cutaneous cancers exist. A biopsy is then performed to confirm the diagnosis. For large lesions a punch or incisional biopsy is taken which must include a portion of normal skin at the lesion edge. If the lesion is small enough to allow direct closure, an excision biopsy is performed, with a minimum margin of 2mm. Shave biopsy can be employed to confirm a diagnosis, but care must be taken that the subsequent management of the lesion is not adversely affected. With the rare tumors diagnosis can be difficult and there may not be enough tissue in a biopsy for a definitive diagnosis. The whole lesion may therefore need to be excised to obtain a confident diagnosis with further surgical treatment planned as required. Once the diagnosis is established a decision on the method of treatment can be made. The limited literature would suggest that rare skin tumors are unresponsive to radiotherapy and chemotherapy, so the mainstay of treatment is surgery. When there are no established guidelines for the treatment of a particular rare tumor a pathologist can usually provide advice as to the probable nature of the lesion. This allows surgical treatment to be positioned into one of three main groups: lesions that behave like basal cell carcinomas (BCC); lesions that behave like squamous cell carcinomas (SCC) and; lesions that behave like soft tissue sarcomas (STS). It is helpful to have a management plan into which each variety of rare tumor can be fitted, giving guidance as to the best and most appropriate management. Grouping treatment into BCC, SCC or STS-like treatment has been useful. As more becomes known regarding these malignancies their subsequent management can be adjusted accordingly. Currently, it would appear wise to treat each under a broader subgroup.

Biomarkers predictive of lymph node metastases in oral squamous cell carcinoma

PURPOSE

The ability of oral squamous cell carcinoma to metastasize to lymph nodes does not always show a relationship with clinical staging. The aim of this study was to attempt to define a trend for predictive histopathologic and/or molecular biomarkers in the development of nodal metastasis by analyzing 2 clinically extreme groups.

PATIENTS AND METHODS

Patients with small primary tumors (T1, T2) with lymph node metastasis and patients with large primary tumors (T3, T4) without metastatic disease were identified among 315 consecutive cases of primary oral squamous cell carcinoma. Group comparisons were made with use of a Mann-Whitney test, and associations among the variables were assessed with nonparametric and parametric correlational analyses.

RESULTS

The degree of keratinization was significantly less in primary tumors with lymph node metastasis (P < or = .01). The degree of keratinization was significantly associated with nuclear pleomorphism (P =.02), number of mitoses (P =.02), stage of invasion (P =.002), and p53 expression (P =.04), independent of clinical stage of the tumor. Other microscopic features and immunohistochemical markers did not differ significantly between the groups (P >.05).

CONCLUSION

These data indicate that there still is no single predictive parameter superior to the degree of keratinization to identify patients at risk for the development of regional metastasis.

Lymph node metastases: CT and MRI

Imaging is playing a major role in the assessment of cervical lymphadenopathy. In head and neck malignancies, imaging can be helpful for staging, and sometimes in differentiating different types of metastases, such as squamous cell carcinomas, non-hodgkins disease and thyroid carcinomas. This article on imaging of cervical lymph node metastases will describe both radiological and clinical aspects. Computed tomography (CT) and magnetic resonance (MR) are widely used for primary tumor and nodal imaging. However, very seldom these modalities have clinical consequences for the management of the neck, such as a wait-and-see policy if no nodes are depicted. This is caused by the limited accuracy of both modalities caused by the fallibility of radiologic criteria for metastases. Ultrasound (US) is hampered by similar morphologic criteria, and only US-guided fine needle aspiration cytology (FNAC) can offer additional cytologic criteria which are more reliable.

Pathology of the N0 neck

The incidence, extent and distribution of nodal metastasis is described in 152 neck dissections from patients with an NO neck undergoing surgery for an intraoral/oropharyngeal squamous cell carcinoma. The preoperative N stage had been determined by palpation under general anaesthesia and magnetic resonance imaging. Metastasis was detected histologically in 32 (21%) of the 152 NO necks. The number of positive nodes per NO neck ranged from 1 to 6. In total, 52 positive nodes were found and 29 (56%) measured 10 mm or less in maximum dimension. Twenty-one dissections (66%) contained a single positive node and 24 (75%) showed a single positive anatomical level. Three cases showed 'skipping' of levels within the neck and one case showed 'peppering'. Seventeen (53%) of the 32 positive NO necks and 31 (60%) of the 52 positive nodes contained only 'micrometastases' (deposits < 3 mm). Microscopic extracapsular spread was evident in five NO necks including one case with extracapsular spread at multiple levels. The study concludes that preoperative staging by palpation and routine magnetic resonance imaging cannot be relied upon to detect early cervical metastatic disease, and the topographic distribution of positive nodes indicates that modified neck dissections should include level IV when the primary tumour involves the tongue.

Magnetic resonance imaging in the assessment of cervical nodal metastasis in oral squamous cell carcinoma

OBJECTIVE

The accurate pre-operative assessment of cervical lymph nodes is a well recognized problem in the management of patients with oral squamous cell carcinoma. Imaging techniques have improved the accuracy of staging but cannot determine if nodal enlargement is due to reactive changes or malignant involvement. We assessed the diagnostic performance of magnetic resonance imaging (MRI) in detecting metastatic disease within the neck in oral cancer patients.

MATERIALS AND METHODS

A retrospective study was performed on 58 patients treated for oral squamous cell carcinoma. All patients had pre-operative MR imaging including axial and coronal short tau inversion recovery (STIR) sequences and pre- and post-gadolinium axial T1 weighted sequences. Nineteen patients had bilateral neck dissections giving 77 sides of neck for study. MR images were reviewed for nodal involvement at each anatomical level within the neck and correlated with findings at histology.

RESULTS

Twenty-seven of the 77 sides of neck contained histologically positive nodes (35.1%). MRI sensitivity was 66.7% and specificity 68%. There was a false-negative rate of 20.9% and false-positive rate of 47.1%. Some enlarged, histologically positive nodes were not detected by MRI. Furthermore, in five cases the only histological evidence of nodal malignancy was the presence of a micrometastasis (<3 mm tumour deposit). MRI detected two of these.

CONCLUSION

MRI lacks sufficient sensitivity and specificity to replace elective neck dissection for both staging and prognostic purposes.

Metastatic tumours of the parotid gland

Twenty patients (12 men and 8 women, median age 69 years) with metastatic tumours in the parotid gland who presented over a 12-year period were evaluated retrospectively. Preoperative investigations included fine needle aspiration cytology (n = 11) and computed tomography or magnetic resonance imaging (MRI) (n = 14). Most tumours originated from the head and neck region, the two main types being squamous cell carcinoma (n = 10) and malignant melanoma (n = 7). All 20 presented with a parotid mass and 11/20 (55%) had associated lymphadenopathy. Eleven patients (55%) underwent superficial, five total, and four radical, parotidectomy. Neck dissection was required in 16 patients (80%), and all 11 patients with clinically palpable lymph nodes had evidence of tumour in the neck dissection specimens. Half of all patients (n = 10) received adjuvant postoperative radiotherapy. Three-quarters of the patients (n = 15) were alive after a mean follow-up of 31 months and only one developed a marginal recurrence. The cumulative 5-year survival rate was 51%, and there was no significant difference (P = 0.48) in the 3-year survival rates of patients who had radical compared with those who had modified neck dissections. Patients who had superficial parotidectomy had a longer overall survival compared with those who had total or radical parotidectomy (P = 0.04) perhaps reflecting the advanced nature of tumours that required total or radical excision of the gland. We conclude that superficial parotidectomy is usually an adequate treatment for secondary parotid tumours (when disease is clinically limited to the superficial lobe), and we suggest that patients in whom metastatic disease of the parotid gland is suspected do not require neck dissection if they have no palpable lymph nodes and MRI shows no evidence of spread. There seems to be no survival advantage in radical over modified neck dissection.

Malignant tumours of the submandibular salivary gland: a 15-year review

Malignant tumours of the submandibular salivary gland are rare, difficult to distinguish clinically from benign disease and often only diagnosed after initial excision of the enlarged gland. In this study of 70 patients (46 male, 24 female) with a mean age of 64 years (range 17-94), and an average duration of symptoms of 3 months, a painless submandibular swelling was the most common presentation. Of the 69 primary tumours, the most frequent histological types were adenoid cystic carcinomas (26 patients, 37%) and carcinoma ex-PSA (18 patients, 26%). One tumour was metastatic in origin, arising from a parotid primary. A total of 65 patients were treated by primary excision of the gland while five patients who presented with advanced disease were treated by radiotherapy alone. Adjuvant postoperative radiotherapy was utilised in 53 (75%) of patients. After a mean follow-up of 5 years, 32 (46%) of patients are still alive. Metastatic disease accounted for 21 deaths (30%). The clinical stage at presentation was the most significant factor predicting survival.

Malignant tumours of the parotid gland: a 12-year review

Malignant parotid tumours are uncommon and present a significant management challenge. Fifty-one such patients (25 male, 26 female, median age 64 years) operated on in the Newcastle Plastic Surgery Unit between 1983 and 1994 were retrospectively evaluated. Preoperative investigations included FNA cytology (n = 20), and for staging CT and/or MRI scans (n = 21). Of the 35 primary tumours 32 were epithelial and three lymphomatous. Metastatic tumours were squamous cell carcinoma (7), melanoma (6), renal cell carcinoma (2) and sebaceous carcinoma (1). FNA cytology correctly diagnosed malignancy with an 88% sensitivity (false negatives = 2). A total or radical parotidectomy was required in 60% of patients, the rest undergoing superficial parotidectomy. In continuity neck dissection was undertaken in 23 (45%) cases. Postparotidectomy reconstruction included 10 free, 3 myocutaneous, and 4 local transposition/rotation flaps. Thirty-seven patients (73%) received postoperative radiotherapy. Seventy-two per cent of patients are alive after a mean follow-up of 42 months. The crude 5- and 10-year survival rates were 68% and 49% respectively while the loco-regional control rate (Kaplan-Meier method) at 10 years was 79%. Fifteen patients (30%) have permanent facial palsy. It is concluded that radical surgery with appropriate reconstruction followed by planned postoperative adjuvant radiotherapy gives effective control of malignant parotid tumours.

Detection of latero-cervical metastases from oral cancer

In squamous cell carcinoma of the oral cavity, the presence of nodal metastases greatly influences prognosis. The evaluation of regional lymph nodal involvement is crucial in the correct management of these neoplasms. The records of 45 patients with oral cancer were reviewed retrospectively to evaluate the accuracy and prognostic value of the techniques used to detect lymph node metastasis in the neck (clinical examination, echo-colour-Doppler, computed tomography and magnetic resonance imaging). Echo-colour-Doppler was the most accurate procedure with a predictive positive value of 95.6% and the lowest false-negative rate. Therefore, a diagnostic preoperative study must include echo-colour-Doppler preferably associated with computed tomography to achieve the greatest diagnostic accuracy.

MRI T staging of squamous cell carcinoma of the oral cavity: radiological-pathological correlation

Fifty patients with primary or suspected recurrent squamous cell carcinoma of the oral cavity were examined pre-operatively with magnetic resonance imaging (MRI) to determine the tumour stage. Pathological correlation was available in all cases. Twenty-five of 35 patients with primary disease were correctly staged (MR Tstage 0-4). In another four patients there was good size correlation between MR and pathology, but two cases had false positive MR interpretation of bone invasion. MRI has proved accurate at excluding the presence of bone invasion (negative predictive value 97%), but a positive scan may not discriminate between tumour and other dental pathology (positive predictive value 67%). Assessment of local extent was otherwise good with invasion of muscles of the floor of the mouth and muscles of mastication always predicted correctly. Salivary gland abnormality was frequent, and MRI correctly distinguished between obstructive sialectasis and direct invasion. The results of MR staging in patients with recurrent disease were less accurate. Where diagnostic scans can be obtained MRI can provide useful information for the surgeon or radiotherapist regarding the local extent of tumour, and may assist in treatment planning. Assessment of cervical lymphadenopathy can be performed as part of same procedure.

Correlation of histopathologic findings with clinical and radiologic assessments of cervical lymph-node metastases in oral cancer

The accuracy of preoperative diagnosis of cervical lymph-node metastasis in oral cancer was assessed by comparing the histopathologic findings in 136 sides of neck dissection with physical examination under anaesthesia (EUA) and computerized tomography (CT) assessments of the metastatic status. The overall accuracy of EUA and CT assessments was 72% and 73%, respectively, and a combination of both methods resulted in sensitivity and specificity rates of 55% and 78%, respectively. Twenty-three of the 51 histologically positive necks had been assessed as negative on both EUA and CT. Six of these contained only micro-metastases, and in another 10, the largest positive node was 1.5 cm or less. Extracapsular spread of metastatic carcinoma was found in 12 of the 23 EUA and CT false-negative dissections. Most of the 21 histologically positive necks which had been correctly assessed as positive on both EUA and CT contained enlarged metastatic nodes, fused nodal masses, extensive extracapsular spread, or more than one of these features. Three of the 85 histologically negative necks had been assessed as positive on both EUA and CT; eight had been positive on EUA alone, and another eight on CT alone. Reactive nodal hyperplasia or sialadenitis was seen in most false-positive dissections. We conclude that the accuracy of preoperative diagnosis of metastasis by routine methods remains poor, and that EUA and CT are reliable only in patients with bulky metastatic deposits.