Usefulness of ultrasonography for diagnosis of malignant lymphoma of the thyroid

The potential value of ultrasound in predicting local refractory/relapse events in primary thyroid lymphoma patients

BACKGROUND

Primary thyroid lymphoma (PTL) is a rare malignant disorder, and ultrasound plays an important role in PTL diagnosis and follow-up surveillance. Prediction of refractory/relapse events in PTL patients is an essential issue, yet no ultrasonic PTL features have been discovered to be related to refractory/local relapse events.

METHODS

From January 2008 to September 2022, newly diagnosed PTL patients in our center who underwent standard first-line treatment and received an ultrasound examination before treatment were enrolled. Data regarding patients' clinical and sonographic features, as well as their therapeutic responses were collected. Subjects with an ideal prognosis were compared to those with refractory/relapse events.

RESULTS

In total, 37 PTL patients were analyzed, including 26 with diffuse large B-cell lymphoma, 2 with follicular lymphoma and 9 with mucosa-associated lymphoid tissue lymphoma. During the median follow-up of 25 months, 30 patients obtained a complete response, 4 were refractory patients, and 3 experienced local relapse. No significant difference was detected in the baseline clinical characteristics between patients with an ideal prognosis and those with refractory/local relapse events. In terms of sonographic features, however, an event-free survival (EFS) curve comparison revealed that patients with bilobar enlargement (defined as an anterior-posterior diameter > 2.5 cm on both sides of thyroid lobes) had a poorer EFS than those without (P < 0.0001), and patients with diffuse type had a poorer EFS than those with mixed/nodular types (P = 0.043). No significant difference was observed in EFS between patients with or without signs of suspicious cervical lymph node metastasis, rich blood signal distribution or symptoms of trachea compression.

CONCLUSIONS

PTL patients with an anterior-posterior diameter > 2.5 cm for both thyroid lobes or PTL patients of the diffuse ultrasound type could be prone to refractory/local relapse events.

Primary Thyroid Lymphoma: How Molecular Biology and Ancillary Techniques Can Help the Cytopathologist Overcome This Diagnostic Challenge

Primary thyroid lymphoma (PTL) occurs rarely, its diagnosis is a challenge, and the prognosis of these patients depends on the time of diagnosis. Even though fine-needle aspiration cytology (FNAC) is recognized as the most accurate tool for detecting thyroid malignancies, its sensitivity for PTL is poor. Both clinical and ultrasound presentation of PTL can be atypical, and laboratory tests fail to furnish relevant data. Consequently, the reliability of a cytopathologist facing PTL can be poor, even when he is aware of its clinical information. In addition, the cases described in the literature are extremely rare and fragmentary, and consequently, the molecular data currently available for this neoplasm are practically negligible. Here, we present a case report in order to discuss the intrinsic limitations in achieving a final diagnosis of PTL and how using molecular diagnostics to identify potential mutational models can improve the evaluation of this neoplasm.

Multimodal Sonographic Appearance and Survival Outcomes of 69 Cases of Primary Thyroid Lymphoma Over 10 Years

OBJECTIVES

To investigate ultrasound appearance and the survival outcomes for patients with primary thyroid lymphoma (PTL).

METHODS

Ultrasonic images and clinical characteristics from pathologically confirmed 69 PTL patients (2008-2019) were retrospectively analyzed. The clinical characteristics, ultrasonic characters, and prognostic factors were analyzed. Survival curves were plotted using the Kaplan-Meier method. Univariate and multivariate analyses were performed.

RESULTS

Of the 69 study patients, 23 were indolent PTL and 46 were aggressive PTL. Age (>70 years old) and elevated lactate dehydrogenase levels were statistically different clinical features between aggressive and indolent PTL. From ultrasonic images, 34 cases were nodular, 11 diffuse, and 24 mixed pattern. Mixed types displayed high invasiveness (45.7%) while diffuse types displayed higher inertness (39.1%), with statistically significant differences (P = .000). Invaded thyroid capsule and increased chaotic vascularity also showed significant differences between aggressive and indolent PTL. We also observed statistical difference in overall survival rates between aggressive and indolent PTL (P = .032). Single factor K-M analyses showed that age >70 years, aggressive pathology, and Ki67 >30% were positively correlated with the risk of poor PTL survival (P < .05).

CONCLUSIONS

Multimodal ultrasound provides accurate ultrasonographic information and facilitates PTL invasiveness diagnostics for improved clinical treatment. In addition, PTL patients aged >70 years, with aggressive pathology, and Ki67 >30% were more likely to have a poor survival outcome.

Diffuse Large B-Cell Lymphoma of Thyroid: A Case Report and Review of Literature

Primary thyroid lymphoma is a rare malignancy, accounting for 1-2% of extra-nodal lymphomas and 1-5% of thyroid malignancies. Diffuse large B-cell lymphoma is the most common type of primary thyroid lymphoma. It usually presents with a rapidly enlarging neck mass with cervical lymphadenopathy. Though rare, early diagnosis of this condition is important because its management is quite different from the treatment of other thyroid neoplasms. It is usually treated by chemotherapy with or without radiotherapy. We present the case of a 43 years old male who presented with thyroid swelling which on histopathology and subsequent immunohistochemistry was confirmed as diffuse large B-cell lymphoma of the thyroid.

Differential diagnosis of non-diffuse primary thyroid lymphoma and papillary thyroid carcinoma by ultrasound combined with computed tomography

Background

Primary thyroid lymphoma (PTL) and papillary thyroid carcinoma (PTC) are both thyroid malignancies, but their therapeutic methods and prognosis are different. This study aims to explore their sonographic and computed tomography(CT)features, and to improve the early diagnosis rate.

Methods

The clinical and imaging data of 50 patients with non-diffuse PTL and 100 patients with PTC confirmed by pathology were retrospectively analysed.

Results

Of the 150 patients, from the perspective of clinical data, between non-diffuse PTL and PTC patients existed significant difference in age, maximum diameter of nodule, asymmetric enlargement and Hashimoto’s thyroiditis (P < 0.001), but not in gender ratio, echo texture, cystic change and anteroposterior-to-transverse ratio (P > 0.05). With respect to sonographic feature, non-diffuse PTL patients had a higher proportion than PTC patients in markedly hypoechoic, internal linear echogenic strands, posterior echo enhancement, rich vascularity, lack of calcification and homogeneous enhancement, with statistically significant difference (P < 0.05), while PTC patients had a higher proportion than non-diffuse PTL patients in irregular border, circumscribed margin, capsular invasion and significant enhancement, with statistically significant difference (P < 0.001). With respect to CT feature, non-diffuse PTL patients were significantly different from PTC patients in the non-contrast CT value mean, venous phase CT value mean, enhanced intensity and homogeneity of nodules (P < 0.05). Multivariate logistic regression analysis showed that age (OR = 1.226, 95%CI:1.056 ~ 1.423, P = 0.007), posterior echo enhancement (OR = 51.152, 95%CI: 2.934 ~ 891.738, P = 0.007), lack of calcification (OR = 0.013, 95%CI: 0.000 ~ 0.400, P = 0.013) and homogeneous enhancement (OR = 0.020, 95%CI: 0.001 ~ 0.507, P = 0.018) were independent risk factors.

Conclusions

Sonographic and CT features of the presence of posterior echo enhancement, lack of calcification and homogeneous enhancement were valuable to distinguishing non-diffuse PTL from PTC.

The usefulness of serial ultrasound in thyroid mucosa-associated lymphoid tissue lymphoma

BACKGROUND

Mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal lymphoma with an indolent natural course. The thyroid gland is an uncommon site of involvement. We aimed to investigate serial ultrasound features and the disease progression during the clinical course of thyroid MALT lymphoma.

METHODS

We searched our hospital's pathology database (5,418 patients with thyroid malignancy) between January 2000 and July 2022. The medical records and serial ultrasounds of 11 patients with 12 thyroid MALT lymphoma foci were analyzed retrospectively.

RESULTS

An enlarging neck mass, dyspnea, B symptoms, and neck lymphadenopathy were seen at diagnosis in 9 (9/11, 81.8%), 3 (3/11, 27.3%), 2 (2/11, 18.2%), and 9 (9/11, 81.8%) cases, respectively. Eleven cases were concomitant Hashimoto thyroiditis. Common ultrasound features included bilateral or unilateral asymmetric goiter or large, solid, and very hypoechoic nodules (11/12, 91.7%) interspersed with linear, reticular hyperechoic, and enhanced posterior echoes (11/12, 91.7%), and neck lymph node involvement (10/11, 90.9%). The Thyroid Imaging and Reporting Data System (TIRADS) categories showed higher diagnostic accuracy (11/12, 91.7%) than real-time ultrasound (2/12, 16.7%) in evaluating thyroid lesions for recommendation of fine-needle aspiration (FNA). Serial ultrasound showed self-limiting changes in three cases, relapse in three cases after subtotal thyroidectomy and chemotherapy, large cell transformation (LCT) in one case after left lobectomy, partial remission in one case, and complete remission after chemo/radiation in four cases; progression to enlarged thyroid nodules occurred in three cases without treatment, with no obvious change observed after diagnosis. Three patients died during follow-up.

CONCLUSION

On sonograms, solid large thyroid nodules or goiter with very hypoechoic and enhanced posterior echoes in the setting of Hashimoto thyroiditis should raise suspicion for MALT lymphoma. TIRADS categories can improve the ultrasound diagnostic efficacy for malignancy. Serial ultrasound examinations demonstrated self-limiting and indolent natures of thyroid MALT lymphoma.

A diffuse large B-cell thyroid lymphoma presented as a compressive goiter in a young woman with no evidence of Hashimoto's thyroiditis

Thyroid lymphoma should be suspected in case of rapid enlargement of the thyroid gland even in a young patient with no history of Hashimoto thyroiditis. The confirmation is based on histopathology and immunohistochemistry.

Contrast-Enhanced Ultrasound in the Differential Diagnosis of Primary Thyroid Lymphoma and Nodular Hashimoto's Thyroiditis in a Background of Heterogeneous Parenchyma

Objective

To investigate the diagnostic performance of contrast-enhanced ultrasound (CEUS) in the differentiation of primary thyroid lymphoma (PTL) and nodular Hashimoto’s thyroiditis (NHT) in patients with background of heterogeneous diffuse Hashimoto’s thyroiditis (HT).

Methods

Sixty HT patients with 64 thyroid nodules (31 PTL and 33 NHT) who had undergone CEUS examination were included in this study. With histopathological results as the reference, we evaluated the imaging features of each nodule on both conventional ultrasonography (US) and CEUS. Quantitative CEUS parameters including peak intensity (PI), time to peak (TTP), and area under the time–intensity curve (AUC) were gathered in the nodule and background parenchyma. The ratio indexes of theses parameters were calculated by the ratio of the lesion and the corresponding thyroid parenchyma. Logistic regression and receiver operating characteristic (ROC) curves analyses of valuable US indicators were further preformed to evaluate the diagnostic capability of CEUS in discrimination of PTL and NHT.

Results

Among all the observed US imaging features and CEUS parameters, 10 indicators showed significant differences between PTL and NHT (all P < 0.05). All the significant indicators were ranked according to the odds ratios (ORs). Eight of them were CEUS associated including imaging features of enhancement pattern, degree, homogeneity, and quantification parameters of PI, AUC, ratios of PI, AUC, and TTP, while indicators on conventional US, including vascularity and size ranked the last two with ORs less than 3. The five single CEUS parameters showed good diagnostic performance in diagnosis of PTL with areas under ROC curves of 0.72–0.83 and accuracies of 70.3–75.0%. The combination of CEUS imaging features and the ratios of PI, AUC, and TTP demonstrated excellent diagnostic efficiency and achieved area under ROC curve of 0.92, which was significantly higher than any of the five single parameters (all P < 0.05), with a sensitivity of 83.9%, specificity of 87.9%, and accuracy of 85.9%.

Conclusions

CEUS is an efficient diagnostic tool in the differential diagnosis of PTL and NHT for patients with diffuse HT. Conjoint analysis of CEUS imaging features and quantification parameters could improve the diagnostic values.

Diagnostic Performance of Ultrasound Computer-Aided Diagnosis Software Compared with That of Radiologists with Different Levels of Expertise for Thyroid Malignancy: A Multicenter Prospective Study

The aim of the work described here was to evaluate the diagnostic performance of ultrasound thyroid computer-aided diagnosis (CAD) software. This multicenter prospective study included 494 patients (565 thyroid nodules) who underwent surgery or biopsy after ultrasonography at four hospitals from January 2019 to September 2019. The diagnostic performance metrics of different readers were calculated and compared with the pathologic results. The sensitivity of CAD was outstanding and was equivalent to that of a senior radiologist (90.51% vs. 88.47%, p > 0.05). The area under the curve of CAD was equivalent to that of a junior radiologist (0.748 vs. 0.739, p > 0.05). However, the specificity was only 49.63%, which was lower than those of the three radiologists (75.56%, 85.93% and 90.37% for the junior, intermediate and senior radiologists, respectively). The diagnostic performance of the junior radiologist was significantly improved with the aid of CAD (junior + CAD). The sensitivity and area under the curve of junior + CAD were improved from 72.20% to 89.93% and from 0.739 to 0.816, respectively (both p values <0.05), and the positive predictive value, negative predictive value and κ coefficient improved from 76.3% to 78.6%, 82.0% to 86.8% and 0.394 to 0.511, respectively. Though specificity slightly decreased from 75.56% to 73.33%, the difference was not statistically significant (p > 0.05). In general, the clinical application value of CAD is promising, and its instrumental value for junior radiologists is significant.

Prevalence and diagnostic challenges of thyroid lymphoma: a multi-institutional study in non-Western countries

Research on the primary thyroid lymphoma (PTL) diagnosis is limited, with only a few large sample size studies, reported from Asian countries. The aim of the present study was to clarify the current prevalence and challenges in PTL diagnosis, and recommended ancillary studies for PTL in non-Western countries. PTL (n = 153) cases were retrieved from 10 institutions in non-Western countries and analyzed. Ultrasound examination (UE) and fine needle aspiration cytology (FNAC) were used as main preoperative diagnostic tools in all participating institutions. Flow cytometry (FCM) was performed in the 5 institutions (50%). Lobectomy was the most common histological procedure to confirm the PTL diagnosis. All institutions routinely performed immuno-histochemical analysis. PTL was 0.54% of malignant thyroid tumor cases, with mucosa-associated lymphoid tissue lymphoma (MALTL) and diffuse large B-cell lymphoma (DLBCL) being 54.9% and 38.6%, respectively. Kuma Hospital, where the frequency of MALTL was highest (83.7%), routinely performed FCM using the materials obtained by FNAC. UE and FNAC sensitivities were 62.5% and 57.8%, respectively. In both UE and FNAC, sensitivity of MALTL was lower than of DLBCL. The study elucidated that the prevalence of PTL in non-Western countries was lower than previously reported. We propose that FCM should be more actively used to improve the preoperative diagnosis of MALTL. Our data predicted that the MALTL proportion will increase with improved diagnostic tools, while observation of PTL-suspected nodules without histological examination remains a viable option.

2020 Chinese guidelines for ultrasound malignancy risk stratification of thyroid nodules: the C-TIRADS

Thyroid nodules are very common all over the world, and China is no exception. Ultrasound plays an important role in determining the risk stratification of thyroid nodules, which is critical for clinical management of thyroid nodules. For the past few years, many versions of TIRADS (Thyroid Imaging Reporting and Data System) have been put forward by several institutions with the aim to identify whether nodules require fine-needle biopsy or ultrasound follow-up. However, no version of TIRADS has been widely adopted worldwide till date. In China, as many as ten versions of TIRADS have been used in different hospitals nationwide, causing a lot of confusion. With the support of the Superficial Organ and Vascular Ultrasound Group of the Society of Ultrasound in Medicine of the Chinese Medical Association, the Chinese-TIRADS that is in line with China's national conditions and medical status was established based on literature review, expert consensus, and multicenter data provided by the Chinese Artificial Intelligence Alliance for Thyroid and Breast Ultrasound.

Thyroid lymphoproliferative lesions in Asia

Primary thyroid lymphomas (PTLs) are rare and most commonly present as rapidly enlarging thyroid mass causing obstructive symptoms. Due to worldwide differences in clinical practices related to thyroid malignancy, this review was conducted to compare the clinicopathological and diagnostic modalities related to PTL and their similarities and differences between the Asian and Western countries. Using the search engine PubMed, published data on thyroid lymphomas was collected and reviewed. A total of 18 Asian and 22 Western studies were included. Most of PTLs were B-cell Non-Hodgkin lymphomas (NHL). While mucosa-associated lymphoid tissue (MALT) lymphoma was the commonest (41.1%) among Asians, diffuse large B cell lymphoma (DLBCL) (71.9%) predominated in the Western population. Some rare subtypes of PTL were also identified. Majority of all patients in Asian as well as Western studies presented with early stage (stage I/II) disease. Interestingly, when compared with Asian patients, a larger proportion of patients from the West presented with higher stage (stage III/IV) disease (12.2% vs. 3%). Ultrasonography (USG) and fine needle aspiration cytology (FNAC) in addition to histological examination usually by core needle biopsy and in some by open procedures were used for the diagnosis of PTL in both the cohorts. The various ancillary techniques used were immunocytochemistry (ICC), flowcytometry (FC), immunohistochemistry (IHC), and molecular testing. The use of ancillary techniques for PTL diagnosis was more common in the West compared to Asia and markedly increased the sensitivity of cytology to diagnose PTL. Treatment and prognosis largely depend upon the subtype of PTL and stage at presentation. To conclude, from the available published literature, there is an apparent difference between Asian and Western cohorts in the histological type and stage of presentation of PTL, but the results may be affected by publication and selection bias. Also, advanced ancillary techniques are more commonly adopted in the West.

Diagnosis methods and treatment strategy for primary thyroid lymphoma: a retrospective analysis of 41 cases in China

Primary thyroid lymphoma (PTL) is a rare malignant tumor. It can manifest as a rapidly growing mass and produce various compression symptoms. However, PTL is easily missed or misdiagnosed for the lack of standardized diagnostic methods. Therefore, it is very necessary to analyze the diagnosis methods and treatment strategy of PTL to clarify the guide of diagnosis and treatment. In this study, we retrospectively analyzed PTL patients to determine their clinical, ultrasound and histological features. Forty-one PTL cases were analyzed. The pathological results of all cases were B-cell-derived non-Hodgkin's lymphoma. In these patients, 12 were mucosa-associated lymphoid tissue lymphomas, and 24 were diffuse large B-cell lymphomas. Through the analysis of the clinical, ultrasonographic and histological features of 41 patients with PTL, and the discussion of treatment strategies, we support that middle-aged women with a history of Hashimoto's thyroiditis should pay more attention to the possibility of PTL if they have a swelling neck. Thyroid function tests and neck ultrasound are routine examinations. Core biopsy is an important diagnostic method. PTL treatment is mainly based on radiotherapy and chemotherapy, and surgery is not the first choice.

Ultrasonography in the Diagnosis and Monitoring of Therapy for Primary Thyroid Lymphoma

This study aims to evaluate the value of ultrasonography in the diagnosis, treatment, and follow-up of primary thyroid lymphoma. The clinical data of 12 patients, who were pathologically confirmed with thyroid lymphoma and treated in our hospital, were retrospectively analyzed. Ultrasonography was performed on the thyroid and neck lymph nodes, and the sonographic features of the lesions were recorded. During the course of the diagnosis and treatment of lymphoma, the patients were monitored and followed up by ultrasonography. The sonographic features of 12 patients with 20 lesions revealed hypoechoic masses, within which "strip-shaped" and "grid-shaped" high echoes were observed, and echoes behind masses were not attenuated. Furthermore, a small amount of blood flow signals were observed. Six patients received thyroidectomy. Among these patients, one patient relapsed. Six patients underwent chemotherapy. Among these patients, 2 patients relapsed and received chemotherapy again. Ultrasound can guide the biopsy of suspicious lymphoma lesions and provide accurate information on treatment effects and tumor recurrence for patients with thyroid lymphoma after treatment, especially after chemotherapy.

A comparative analysis of diffusion-weighted imaging and ultrasound in thyroid nodules

BACKGROUND

Diffusion-weighted imaging (DWI) and ultrasound are commonly used methods to examine thyroid nodules, but their comparative value is rarely studied. We evaluated the utility of DWI and ultrasound in differentiating benign and malignant thyroid nodules.

METHODS

A total of 100 patients with 137 nodules who underwent both DWI and ultrasound before operation were enrolled. The T1 and T2 signal intensity ratio (SIR) of each thyroid nodule was calculated by measuring the mean signal intensity divided by that of paraspinal muscle. The apparent diffusion coefficient (ADC) value and the SIR of benign and malignant thyroid nodules were analyzed by two-sample independent t tests. The sensitivity, specificity, and accuracy of DWI and ultrasound were compared with chi-square tests.

RESULTS

There was no significant difference in the SIR between benign and malignant thyroid nodules. The ADC value was significantly different. At the threshold value was 1.12 × 10^- 3 mm²/s, the maximum area under the curve was 0.944. The sensitivity, specificity, and accuracy were 84.9, 92.2, and 87.6% respectively. The corresponding values of ultrasound diagnosis were 90.1, 80.4, and 86.9%.

CONCLUSIONS

Ultrasound has high sensitivity in differentiating benign and malignant thyroid nodules, and the ADC value has high specificity, but there is no statistical difference in sensitivity or specificity between the two modalities. DWI and ultrasound each have their own advantages in differentiating benign and malignant thyroid nodules.

[A retrospective analysis of 12 cases of primary thyroid lymphoma]

OBJECTIVE

To discuss the clinical characteristics and diagnostic and therapeutic considerations of primary thyroid lymphoma (PTL) by reviewing PTL cases.

METHODS

In the study, 12 cases of PTL diagnosed and treated in Peking University First Hospital between January 1995 and September 2015 were identified. The clinical characteristics, management experiences and prognosis of these cases were reviewed retrospectively.

RESULTS

A total of 12 PTL patients (four males and eight females) were collected, with an average age of 63 years (42 to 81 years) at the time of diagnosis. The average time to clarify diagnosis was 5 months (0.5 to 24 months). Eleven patients presented with a rapidly growing neck mass and visited surgical department, except one complained of coughing and suffocated. Seven patients were hypothyroid, and four were euthyroid at the time of diagnosis. In sonography of 11 cases, nine showed bilateral nodules, with an average diameter of 3.87 cm. Pathologic diagnosis of non-Hodgkin's lymphoma was confirmed in all the 12 cases by means of partial thyroidectomy (four) or core needle biopsy (eight). The pathological subtypes were diffuse large B cell lymphoma in nine patients, mucosa-associated lymphoid tissue lymphoma (MALToma) in two, and small B cell lymphoma in the other one patient. Five patients were concomitant with Hashimoto's thyroiditis. Eleven patients received chemotherapy. Only one patient did not have any further treatment after operation due to an inertia type of tumor. The median overall survival time was 24 months (1-117 months), three patients died. Among the patients who survived, seven completed chemotherapy without disease progression, one MALToma case did not receive chemotherapy after thyroidectomy but was still alive with PTL, and one patient just finished his second course of chemotherapy.

CONCLUSION

The diagnosis of PTL should be considered when dealing with rapidly growing goiters in elder female Hashimoto's thyroiditis patients whose B ultrasound indicates hypoechogenicity in thyroid nodules or parenchyma, especially with lymphadenopathy and tracheal compressions. Timely use of coreneedle biopsy on suspicious cases can avoid unnecessary surgical trauma, and chemotherapy is the main treatment.

Characteristics and natural course of hypoechoic thyroid lesions diagnosed as possible thyroid lymphomas by fine needle aspiration cytology

Background

There is little information regarding the natural course of hypoechoic thyroid lesions that are probable or possible thyroid lymphoma based on fine needle aspiration cytology (FNAC) results.

Methods

Sixty-five patients who were diagnosed as probable or possible thyroid lymphoma by ultrasonography (US) and FNAC were investigated. Forty-three patients with strong suspicion underwent thyroid surgery for the diagnosis at our hospital, and 22 patients were followed up with periodic US examination. Thyroid lymphoma was definitely diagnosed in 41 out of 43 patients who underwent thyroid surgery, and such patients were defined as Group A. The outcomes of 22 patients who were followed up without an immediate therapy were analyzed. Their hypoechoic lesions decreased in size (n = 10) or disappeared (n = 2) in 12 of 22 patients, and such patients were defined as Group B. Patients in Group A and B were compared using the Kuma Hospital-US classification (USC), the diagnostic categories of the Bethesda System for Reporting Thyroid Cytopathology, and the κ/λ deviation of the immunoglobulin light chain in the FNAC specimens. Mann-Whitney U-test and chi-squared test (with Yate’s continuity correction) were used to compare the two groups.

Results

The USC of < 3.5 [9/12 (75.0%) in Group B; 10/41 patients (24.4%) in Group A] and the κ/λ deviation ratio of < 3.40 [11/12 (91.7%) in Group B; 17/41 patients (41.5%) in Group A] were significantly more frequent (p < 0.01), and the FNAC of ‘benign’ or ‘atypia of undetermined significance or follicular lesion of undetermined significance (AUS)’ with a comment of possible lymphoma [9/12 (75.0%) in Group B; 12/41 patients (29.3%) in Group A] was significantly more frequent (p < 0.05) in Group B than Group A.

Conclusions

Our study suggests that some hypoechoic thyroid lesions that are possible thyroid lymphoma based on US and FNAC might decrease in size or disappear during the careful observation.

Comparison of sonographic characteristics of primary thyroid lymphoma and anaplastic thyroid carcinoma

BACKGROUND

Although primary thyroid lymphoma (PTL) and anaplastic thyroid carcinoma (ATC) both account for a rare portion of the morbidity of all thyroid malignancies, the therapeutic methods and prognosis for these two diseases are different. The purpose of this study was to investigate the sonographic characteristics of PTL and ATC and to compare the sonographic findings of PTL and ATC.

METHODS

The study included 42 patients with histopathologically proven PTL (n=27) and ATC (n=15). The Clinical characteristics and sonographic findings were retrospectively reviewed and compared between the two groups.

RESULTS

The mean age of patients with ATC was not significantly different from that in patients with PTL (P=0.601). The female-to-male ratio of patients with ATC was significantly lower than that of patients with PTL (P=0.029). Both PTL and ATC commonly present as a relatively large, solid mass on sonography with compressive symptoms, in which hoarseness was seen more frequently in ATC group (66.7%) than in PTL group (14.8%) (P=0.001). There is no significant difference in thyroid size, nodular size, margin, shape, echo texture, echogenicity, cystic change, vascularity and local invasion on sonography between ATC and PTL groups. Echogenic strands, markedly hypoechoic and enhanced posterior echo were seen more frequently in PTL group (92.6%, 92.6%, and 85.2%, respectively) than those in ATC group (6.7%, 60.0%, and 33.3%, respectively) (P<0.05), and calcification was seen more frequently in ATC group (80.0%) than in PTL group (0%) (P<0.001). Three ultrasound patterns were observed for PTL including diffuse type (25.9%), nodular type (48.2%) and mixed type (25.9%), while all ATC cases presented with nodular type (100.0%). Associated Hashimoto's thyroiditis occurred more frequently in PTL group (59.3%) than in ATC group (20.0%) (P=0.023).

CONCLUSIONS

Certain sonographic features as a markedly hypoechogenicity, the presence of an enhanced posterior echo and linear echogenic strands, lack of calcification and associated Hashimoto's thyroiditis were valuable for distinguishing PTL from ATC. In contrast, heterogeneous echogenicity, uncircumscribed margin, irregular shape, and vascular pattern were not specific features for differential diagnosis.

Preoperative diagnostic algorithm of primary thyroid lymphoma using ultrasound, aspiration cytology, and flow cytometry

The aims of this report were to clarify the diagnostic significance of ultrasound (US), fine needle aspiration cytology (FNAC), and flow cytometry for primary thyroid lymphoma, and to establish a preoperative diagnostic algorithm of primary thyroid lymphoma. We retrospectively examined US, FNAC, and flow cytometry in 43 patients with benign lymphoproliferative lesions and 32 patients with primary thyroid lymphoma, who underwent US, FNAC, and flow cytometry at Kuma Hospital between May 2012 and December 2015. Primary thyroid lymphomas included 27 mucosa-associated lymphoid tissue lymphomas, 4 diffuse large B-cell lymphomas, and 1 follicular lymphoma. Flow cytometry had the highest specificity (88.4%) and sensitivity (75.0%). The specificity of US was the lowest (32.6%). Both the positive predictive value (90.5%) and negative predictive value (94.7%) were the highest for FNAC. A scoring system was defined as follows: US, low suspicion 0, intermediate suspicion 1, and high suspicion 2; FNAC, benign 0, undetermined 1, malignant 2; and flow cytometry, 0.33< κ/λ ratio <3 0, κ/λ ratio ≤0.33 2, and κ/λ ratio ≥3 2. We propose that a score ≥4 indicates the need for thyroid resection for diagnosing primary thyroid lymphoma. In such a situation, the case of diffuse large B-cell lymphoma, which was aggressive, was not excluded. Approximately one-fifth of mucosa-associated lymphoid tissue lymphomas may be overlooked, but the patients could be followed up with because of an indolent course.

A Computer-Aided Diagnosis System Using Artificial Intelligence for the Diagnosis and Characterization of Thyroid Nodules on Ultrasound: Initial Clinical Assessment

BACKGROUND

An initial clinical assessment is described of a new, commercially available, computer-aided diagnosis (CAD) system using artificial intelligence (AI) for thyroid ultrasound, and its performance is evaluated in the diagnosis of malignant thyroid nodules and categorization of nodule characteristics.

METHODS

Patients with thyroid nodules with decisive diagnosis, whether benign or malignant, were consecutively enrolled from November 2015 to February 2016. An experienced radiologist reviewed the ultrasound image characteristics of the thyroid nodules, while another radiologist assessed the same thyroid nodules using the CAD system, providing ultrasound characteristics and a diagnosis of whether nodules were benign or malignant. The diagnostic performance and agreement of US characteristics between the experienced radiologist and the CAD system were compared.

RESULTS

In total, 102 thyroid nodules from 89 patients were included; 59 (57.8%) were benign and 43 (42.2%) were malignant. The CAD system showed a similar sensitivity as the experienced radiologist (90.7% vs. 88.4%, p > 0.99), but a lower specificity and a lower area under the receiver operating characteristic (AUROC) curve (specificity: 74.6% vs. 94.9%, p = 0.002; AUROC: 0.83 vs. 0.92, p = 0.021). Classifications of the ultrasound characteristics (composition, orientation, echogenicity, and spongiform) between radiologist and CAD system were in substantial agreement (κ = 0.659, 0.740, 0.733, and 0.658, respectively), while the margin showed a fair agreement (κ = 0.239).

CONCLUSION

The sensitivity of the CAD system using AI for malignant thyroid nodules was as good as that of the experienced radiologist, while specificity and accuracy were lower than those of the experienced radiologist. The CAD system showed an acceptable agreement with the experienced radiologist for characterization of thyroid nodules.

Clinical Presentation and Diagnostic Challenges of Thyroid Lymphoma: A Cohort Study

BACKGROUND

Thyroid lymphoma is a relatively rare disease often posing a diagnostic challenge. Reaching the final diagnosis can be delayed if insufficient biopsy material is obtained for immunohistochemistry analysis. The aim of this study was to evaluate the clinical, biochemical, and radiological features of thyroid lymphoma.

METHODS

A retrospective analysis was conducted of all Mayo Clinic patients evaluated between 2000 and 2014 who had a tissue biopsy positive for thyroid lymphoma.

RESULTS

Seventy-five subjects had biopsy-proven thyroid lymphoma, and 62.7% were primary thyroid lymphomas. The median age at diagnosis was 67 years (range 20-90 years). A total of 50.7% were male, and 54.7% had a history of Hashimoto's thyroiditis. Presenting symptoms included neck mass (88%), dysphagia (45.3%), and hoarseness (37.3%). The typical ultrasound appearance consisted of a solid, hypoechoic mass with increased vascularity and variable edge characteristics. Fine-needle aspiration (FNA) biopsies were abnormal in 70.7% of cases, and 42% indicated a specific lymphoma subtype. The diagnosis was confirmed in 53.3% by core biopsy, in 21.3% by thyroidectomy (partial or total), in 12% through incisional biopsy, and in 12% by lymph node biopsy. Core biopsy had a higher sensitivity compared with FNA (93% vs. 71%, p = 0.006).

CONCLUSION

A rapidly enlarging neck mass in the setting of Hashimoto's thyroiditis should raise suspicion for thyroid lymphoma. Radiologically, this usually presents as a large, unilateral, thyroid-centered mass, hypoechoic by ultrasound, and expanding into adjacent soft tissues. Core-needle biopsy should be the first diagnostic test to expedite reaching the final diagnosis and decrease patient burden of additional tests and interventions.

Primary Burkitt lymphoma of the thyroid gland: case report of an exceptional type of thyroid neoplasm and review of the literature

Background

Primary thyroid lymphoma is an uncommon pathological entity that accounts for only 1 to 5 % of all thyroid malignancies. Primary Burkitt lymphoma of the thyroid gland is very rare. This article presents the first Moroccan case of a primary BL of the thyroid to be reported in the literature to date.

Case presentation

We describe here a case of a 70-year-old male who developed a rapidly enlarging thyroid gland with progressive symptoms of compression. Core biopsy confirmed the diagnosis of Burkitt lymphoma. The patient died of septic shock, 2 weeks after the first cycle of appropriate therapeutic chemotherapy.

Conclusions

This presentation emphasizes the importance of considering lymphoma when dealing with a thyroid mass, as its management is different from that of other thyroid pathologies, and affords an opportunity to review a very rare type of primary thyroid lymphoma.

Ultrasonographic features of aggressive primary thyroid diffuse B-cell lymphoma: A report of two cases

Primary thyroid lymphoma (PTL) is a relatively rare malignant tumor. Aggressive PTL is extremely rare, and there is limited literature regarding the imaging features of PTL with invasion into adjacent structures, including internal jugular vein, muscles, esophagus, trachea and carotid artery. In addition, the ultrasonographic features of the cases presented in the current report differ from those reported in previous studies. In the present study, two cases of PTL, who presented to The First Affiliated Hospital of Wannan Medical College (Wuhu, China) with a short history of a rapidly growing mass in the front of their neck, are reported. Both patients had undergone ultrasound examination, and the subsequent histopathological and immunohistochemical examinations confirmed that the two masses were primary diffuse large B-cell lymphoma. The ultrasonographic findings of these two cases are discussed in the present report.

Development of Primary Thyroid Lymphoma during an Ultrasonographic Follow-up of Hashimoto's Thyroiditis: A Report of 9 Cases

We herein experienced 9 patients with primary thyroid lymphoma that developed during 3-18 years of ultrasonographic follow-up of Hashimoto's thyroiditis. All nine patients had localized mucosa-associated lymphoid tissue (MALT) lymphoma. Two patients had diffuse type, one had mixed type, and six had nodular type according to the ultrasonographic classification. A clearly enlarging goiter was observed before the diagnosis of lymphoma in 3 patients. An enlarging goiter was not apparent in the remaining 6 patients with nodular type lymphoma, however, the emergence or enlargement of a hypoechoic nodular lesion was observed. Thyroid MALT lymphoma may be diagnosed early by an ultrasonographic follow-up of Hashimoto's thyroiditis.

12 cases of primary thyroid lymphoma in China

INTRODUCTION

Primary thyroid lymphoma (PTL) is a rare malignant disease, which can be life threatening because of airway obstruction due to a suddenly and rapidly growing mass. Prompt and accurate detection and diagnosis in the early phase of PTL are crucial for the treatment of this disease. However, due to lack of standardized diagnostic procedures and methods, PTL can be easily missed or misdiagnosed.

MATERIALS AND METHODS

In this study, we retrospectively reviewed 12 thyroid lymphomas cases to determine the typical clinical and sonographic profiles of thyroid lymphomas.

RESULTS

All the patients showed symptoms of rapidly developing neck swelling or mass sensation when they underwent diagnostic procedures. We found that, in sonography, 3 of the 12 patients (25.0 %) showed diffuse heterogeneous hypoechoic parenchyma with intervening echogenic septa-like structures, 8 (66.7 %) showed markedly hypoechoic masses, and 1 (8.3 %) showed a mixed pattern. Histological analysis of the lymphomas using paraffin-embedded sections revealed that all the 12 lymphomas were non-Hodgkin lymphoma with a B cell origin: extranodal marginal zone B cell lymphomas of the mucosa-associated lymphoid tissue lymphoma type in 3 (MALT, 25.0 %), and diffuse large B cell lymphomas in 9 (75.0 %) lymphomas. All the MALT patients had diffuse heterogeneous hypoechoic parenchyma in sonography, but only one of them with diffuse large B cell lymphomas had diffuse heterogeneous hypoechoic parenchyma in sonography. Complete remission was achieved in all patients when they were given CHOP or COP therapy accompanied by local radiotherapy after accurate diagnosis of PTL.

CONCLUSION

We analyzed clinical, sonographic and histological features of twelve cases of malignant lymphoma arising in the thyroid gland and proposed a systematic strategy for prompt and accurate diagnosis of PTL.

Primary thyroid lymphoma has different sonographic and color Doppler features compared to nodular goiter

OBJECTIVES

The purpose of this study was to determine the specific sonographic features of primary thyroid lymphoma and its color Doppler pattern compared to nodular goiter.

METHODS

The sonographic findings for 13 surgically proven primary thyroid lymphomas were analyzed and compared to those for 27 nodular goiters.

RESULTS

In accordance with the suggested pathologic patterns, the sonographic patterns of primary thyroid lymphoma could be classified into diffuse and nodular or segmental types based on the distribution of hypoechoic and echogenic structures within the lesions. Some common sonographic characteristics suggesting thyroid malignancy could not facilitate differentiation of primary thyroid lymphoma from nodular goiter. However, a central blood flow pattern would favor the diagnosis of primary thyroid lymphoma, whereas a peripheral pattern would suggest the diagnosis of nodular goiter.

CONCLUSIONS

Primary thyroid lymphoma has characteristic sonographic and Doppler flow features. Along with several other parameters, a central blood flow pattern would highly suggest the diagnosis of primary thyroid lymphoma rather than nodular goiter.

Sonographic appearance of primary thyroid lymphoma-preliminary experience

Objective

Primary thyroid lymphoma (PTL) is an uncommon thyroid malignancy. Despite the rarity of PTL, it is important to recognize PTL promptly because its management differs from that of all the other thyroid neoplasms. This study was designed to investigate the sonographic features of PTL.

Methods

Twenty-seven pathologically confirmed PTLs were categorized into diffuse and non-diffuse type. Sonographic features including thyroid size, thyroid background echotexture, lesion size, echogenecity, calcification, vascularity, cervical lymphadenopathy of each type were retrospectively analyzed.

Results

All 27 PTLs were diffuse large B-cell lymphomas and were accompanied by diffuse Hashimoto's thyroiditis. Ten were diffuse type and seventeen were non-diffuse type sonographically. The observations in diffuse group included goiter (10/10, 100.0%), marked echogenesity (10/10, 100.0%), heterogeneous echotexture (10/10, 100.0%), and cervical lymphadenopathy (4/10, 40.0%). The observations in non-diffuse group included marked hypoechogenicity (17/17, 100.0%), heterogeneous background thyroid gland (17/17, 100.0%), goiter (15/17, 88.2%), increased vascularity (8/13, 61.5%), mulifocality (10/17, 58.8%), and cervical lymphadenopathy (7/17, 41.2%).

Conclusions

Although some common features were found, the sonographic appearance of PTL is unspecific, especially for the diffuse type. Therefore, interventional diagnostic procedures should be warranted in the clinical settings when PTL is suspected.

Demographic and clinical features of autoimmune thyroid disorder in Japanese patients with systemic sclerosis

Autoimmune thyroid disorders (AITD) are characterized by the impairment of the thyroid gland as a result of systemic or organ-specific autoimmune disorders, and the presence of antithyroid autoantibodies, such as antithyroglobulin antibody (AbTg) and antithyroid peroxidase antibody (AbTPO). Several studies have reported the association of AITD with systemic sclerosis (SSc). However, none of those studies analyzed the association between AITD and skin sclerosis in SSc patients. The aim of this study was to examine the demographic and clinical features of SSc patients with AITD treated in our department. Of a total of 210 SSc patients, we identified 30 with AITD (14.3%), including 29 with Hashimoto's disease (13.8%) and one patient with Graves' disease (0.5%), indicating that hypothyroidism was more common among SSc patients with AITD. All patients with AITD were female, and anticentromere antibody positivity, the complication of Sjögren's syndrome, severe facial skin sclerosis and atrophy of the thyroid gland were significantly prevalent in SSc patients with AITD. SSc patients with such clinical features may be at high risk of AITD and require regular follow up of thyroid function including ultrasonography and the examination of serum hormone levels to start an early treatment.

Aggressive primary thyroid lymphoma: imaging features of two elderly patients

We report two cases of aggressive thyroid lymphoma in elderly patients that presented as large infiltrative thyroid masses with extensive invasion to adjacent structures including trachea, esophagus, and common carotid artery. Ultrasonography displayed irregular shaped, heterogeneous hypoechoic mass, mimicking anaplastic carcinoma. Computed tomography showed heterogeneously enhancing mass compared to surrounding muscles without calcification and hemorrhage. After biopsy, the masses were histopathologically diagnosed as lymphoma. Aggressive primary thyroid lymphoma is rare; therefore, here we report its image features, with emphasis on ultrasonographic findings, and discuss its differential diagnosis.

Sonographic findings in three cases of carcinoma showing thymus-like differentiation

Carcinoma showing thymus-like differentiation (CASTLE) is a rare tumor of the thyroid gland or soft tissues of the head and neck. To our knowledge, there have been only a few reports concerning imaging findings of CASTLE. We report herein the sonographic appearances of three cases of CASTLE. Two tumors were located at the lower part of the thyroid and one had spread throughout the thyroid. Sonograms showed heterogeneously solid tumors without cystic components or calcification. The central part of the tumor was slightly hyperechoic compared with the peripheral part of the tumor. Histologically, the tumors were composed of a mixture of fibrous stroma and epithelial nests.

Co-occurrence of papillary thyroid carcinoma and primary lymphoma of the thyroid in a patient with long-standing Hashimoto's thyroiditis

BACKGROUND

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, whereas mucosa-associated lymphoid tissue (MALT) lymphoma of the thyroid gland is uncommon. Simultaneous occurrence of both disease entities is very rare.

PATIENT FINDINGS

A 59-year-old man with known hypothyroidism from Hashimoto's thyroiditis (HT) was seen for thyroid nodules. A thyroid ultrasound revealed a heterogeneous thyroid gland with two hypoechoic nodules, one in the right aspect of the isthmus measuring 2.0 cm×3.2 cm×1.7 cm and another one in the left lobe measuring 1.4 cm×1.3 cm×1.2 cm. A fine-needle aspiration (FNA) of the right-sided nodule revealed atypical epithelial cells and atypical lymphoid cells in a background of lymphocytic thyroiditis; FNA of the left-sided nodule showed findings of PTC. A total thyroidectomy was performed. Lymph node dissection was not performed. Pathology showed extranodal marginal zone B-cell lymphoma of MALT type with extreme plasmacytic differentiation in the right nodule and PTC in the left nodule (pT1b Nx Mx). Postoperatively, he underwent radioactive iodine ablation treatment. There was only minimal neck uptake on the post-treatment scan. Further work-up did not show any evidence of extrathyroidal lymphoma. Seven years after the surgery, the patient had no evidence of recurrence of either malignancy.

SUMMARY

PTC is the most prevalent thyroid cancer and has an excellent prognosis. Primary thyroid lymphoma is rare and accounts for <5% of all thyroid cancers. Among the primary thyroid lymphomas, MALT lymphoma tends to have a more indolent course and a better prognosis. PTC and MALT lymphoma have been associated with HT. FNA has been validated in several studies for the diagnosis of MALT lymphoma; however, distinguishing MALT lymphoma from HT remains a challenge due to their histological similarities. The treatment of MALT lymphoma remains controversial; however, surgery is generally accepted in the early-stage MALT lymphoma as was performed in the present case.

CONCLUSION

Since HT is associated with PTC and MALT lymphoma, patients with HT deserve careful surveillance for both disease entities. In our patient, the management of one malignancy did not affect the management of the other, and the prognosis did not seem to be affected.

Thyroid lymphoma: correlation of radiologic and pathologic features

OBJECTIVES

The purpose of this study was to correlate the clinicoradiologic and pathologic features of thyroid lymphoma and to identify the most useful diagnostic method for thyroid lymphoma as the first line.

METHODS

Our study population included 16 patients with a diagnosis of thyroid lymphoma by fine-needle aspiration, core biopsy, or surgery from 1995 to 2010. We retrospectively reviewed imaging and medical records. Sonographic findings were correlated with histopathologic results.

RESULTS

Of the 16 patients, primary lymphomas were found in 13 and secondary in 3. The mean ages of the patients with primary and secondary lymphomas were 60.8 and 42.7 years, respectively. Most patients with primary lymphomas had symptoms of rapid neck swelling or a mass sensation. All primary lymphomas revealed non-Hodgkin B-cell lymphoma, and secondary lymphomas included a B-cell origin in 2 and a T-cell origin in 1. On sonography, 10 (77%) of 13 primary lymphomas showed diffuse heterogeneous hypoechoic parenchyma with intervening echogenic septa-like structures, whereas all secondary lymphomas showed markedly hypoechoic nodules. Markedly hypoechoic parenchyma was correlated with lymphoepithelial lesions and neoplastic cells, whereas the intervening echogenic septa-like structures were consistent with fibrosis on pathologic examination. The exact diagnosis of thyroid lymphoma was possible with core biopsy in all 9 cases (100%) but with fine-needle aspiration in only 3 of 10 (30%), which included 7 under sonographic guidance and 3 under palpation (P = .0030).

CONCLUSIONS

Diffuse hypoechoic parenchyma with intervening echogenic septa on sonography under the impression of a primary thyroid lymphoma, particularly in the setting of a rapidly enlarging mass, should prompt core biopsy rather than fine-needle aspiration.

Thyroid ultrasonography

BACKGROUND

The recent prevalence of ultrasonography (US) has facilitated the early detection and qualitative evaluation of thyroid nodules. Furthermore, novel technical developments are extending the application range of US for other thyroid diseases.

METHODS

The use of US to differentiate between thyroid carcinoma and benign nodule, between a metastatic lymph node and a reactive node, between thyroid lymphoma and chronic thyroiditis, and between destruction-induced thyrotoxicosis and Graves' disease is introduced.

RESULTS

Classification systems for thyroid nodule have shown high diagnostic accuracy for thyroid carcinomas except follicular carcinoma. US diagnosis of lymph node metastasis showed high specificity but low sensitivity. Patients who were suspected of thyroid lymphoma based on US findings should undergo incisional biopsy or thyroidectomy for diagnosis of the histologic type if fine-needle aspiration biopsy findings suggest lymphoma. Patients should be carefully followed even if they were diagnosed as negative based on cytologic findings. Measurement of thyroid blood flow is helpful for diagnosing destruction-induced thyrotoxicosis, such as painless thyroiditis, by distinguishing the lesion from Graves' disease.

CONCLUSIONS

Ultrasonography is useful for diagnosing various thyroid diseases, including thyroid carcinoma. The remaining issue to be resolved is the diagnosis of follicular carcinoma. Trials using novel techniques to differentiate these lesions are expected.

Clinical characteristics of primary thyroid lymphoma in Koreans

Primary thyroid lymphoma is a very rare tumor and its prevalence is approximately 0.1% of all thyroid cancers in Korea. Its clinical experience is limited and not familiar to physicians. Therefore, we performed this study to investigate the clinical characteristics of primary thyroid lymphoma in Koreans. We retrospectively analyzed the medical records of the 44 patients with primary thyroid lymphoma from 1991 to 2006 at four major referral hospitals in Korea. Out of 44 patients, eight patients were male and 36 patients were female and their average age was 57 years. Fifty-six percent of patients had underlying Hashimoto's thyroiditis. All but two patients had non-Hodgkin's lymphoma with B cell origin, and eighty percent of patients presented with stage IE or IIE. Twenty-one of 44 patients (48%) had diffuse large B cell lymphoma (DLBCL) and 17 (39%) had MALT lymphoma. Malignancies originating from lymphoid cells were suspected in 10 of eighteen patients with DLBCL (56%) by using fine-needle aspiration cytology (FNAC), and no difference was noted compared with MALT lymphoma (64%). Compared with DLBCL, the patients with MALT lymphoma were more frequently presented with stage I disease (DLBCL vs. MALT lymphoma: 32% vs. 65%, P=0.04). Moreover, in contrast to DLBCL, most of the patients with MALT lymphoma achieved complete response with treatments (DLBCL vs. MALT lymphoma: 53% vs. 94%, P<0.01). Because of the low diagnostic accuracy of FNAC, thyroid biopsy should be considered for the diagnosis of thyroid lymphomas in suspicious cases. The patients with MALT lymphoma were more frequently presented with early stage diseases and this might lead to the favorable outcome to treatments than those with DLBCL.

Benign and malignant thyroid nodules: US differentiation--multicenter retrospective study

PURPOSE

To retrospectively evaluate the diagnostic accuracy of ultrasonographic (US) criteria for the depiction of benign and malignant thyroid nodules by using tissue diagnosis as the reference standard.

MATERIALS AND METHODS

This study had institutional review board approval, and informed consent was waived. From January 2003 through June 2003, 8024 consecutive patients had undergone thyroid US at nine affiliated hospitals. A total of 831 patients (716 women, 115 men; mean age, 49.5 years +/- 13.8 [standard deviation]) with 849 nodules (360 malignant, 489 benign) that were diagnosed at surgery or biopsy were included in this study. Three radiologists retrospectively evaluated the following characteristics on US images: nodule size, presence of spongiform appearance, shape, margin, echotexture, echogenicity, and presence of microcalcification, macrocalcification, or rim calcification. A chi(2) test and multiple regression analysis were performed. Sensitivity, specificity, and positive and negative predictive values were obtained.

RESULTS

Statistically significant (P < .05) findings of malignancy were a taller-than-wide shape (sensitivity, 40.0%; specificity, 91.4%), a spiculated margin (sensitivity, 48.3%; specificity, 91.8%), marked hypoechogenicity (sensitivity, 41.4%; specificity, 92.2%), microcalcification (sensitivity, 44.2%; specificity, 90.8%), and macrocalcification (sensitivity, 9.7%; specificity, 96.1%). The US findings for benign nodules were isoechogenicity (sensitivity, 56.6%; specificity, 88.1%; P < .001) and a spongiform appearance (sensitivity, 10.4%; specificity, 99.7%; P < .001). The presence of at least one malignant US finding had a sensitivity of 83.3%, a specificity of 74.0%, and a diagnostic accuracy of 78.0%. For thyroid nodules with a diameter of 1 cm or less, the sensitivity of microcalcifications was lower than that in larger nodules (36.6% vs 51.4%, P < .05).

CONCLUSION

Shape, margin, echogenicity, and presence of calcification are helpful criteria for the discrimination of malignant from benign nodules; the diagnostic accuracy of US criteria is dependent on tumor size.

Ultrasonographic evaluation of thyroid nodules in 900 patients: comparison among ultrasonographic, cytological, and histological findings

Ultrasonography is the most useful tool for detection and evaluation of thyroid nodules. In this study, we present our classification system for ultrasonographic evaluation, which has been routinely performed since 1995. Of 1244 nodules identified by ultrasonography in 900 patients, 1145 nodules demonstrating adequate specimens on fine-needle aspiration biopsy were enrolled in the study. We stratified these nodules into classes 1 to 5 with intermediate steps of 0.5 for classes 2 to 5. Nodules classified as 3.5 or greater were evaluated as malignant, those classified as 3 were evaluated as borderline, and those classified as 2.5 or lower were evaluated as benign. Of 233 nodules evaluated as malignant, 179 (76.8%) were cytologically confirmed as malignant. Furthermore, 145 of 159 nodules (91.2%) classified as 4 or greater were cytologically diagnosed as carcinoma. Of 710 nodules evaluated as benign, 683 (96.1%) were cytologically confirmed as benign. Two hundred fifty-five nodules of 210 patients were surgically resected and pathologically examined. In this series, the positive predictive value of ultrasonographic evaluation of malignancy was 97.2%. These findings suggest that our classification system is simple and useful to facilitate ultrasonographic evaluation of thyroid nodules.

Primary thyroid lymphoma: role of ultrasound-guided needle biopsy

OBJECTIVE

The purpose of this study was to describe the sonographic findings of primary thyroid lymphoma and evaluate the role of ultrasound-guided biopsy in diagnosing thyroid lymphoma.

METHODS

This study included 6 patients (age range, 56-72 years; mean, 62.5 years). We searched the database of our institution and retrospectively collected data on the thyroid lymphomas that were confirmed pathologically. All of the sonograms and medical records were reviewed retrospectively.

RESULTS

All 6 patients had an enlarged neck mass and underwent ultrasound-guided fine-needle aspiration biopsy. The most notable sonographic feature of primary thyroid lymphoma was a marked hypoechoic mass compared with the residual thyroid tissue. Among the 6 patients with a diagnosis of thyroid lymphoma, 3 (50%) had a diagnosis of lymphoma by ultrasound-guided fine-needle aspiration biopsy. Final pathologic results were obtained by ultrasound-guided core needle biopsy (3/6 patients [50%]) or thyroidectomy (3/6 [50%]). Most patients with thyroid lymphoma (5/6 [83.3%]) were found to have diffuse large B-cell lymphoma and were treated with chemotherapy with or without radiotherapy. In 1 patient with follicular lymphoma, diagnosis and treatment were accomplished by total thyroidectomy.

CONCLUSIONS

Our results show that ultrasound-guided core needle biopsy can be a safe and accurate method for diagnosing thyroid lymphoma and may be a suitable replacement for diagnostic thyroid surgery.