Primary thyroid lymphoma: role of ultrasound-guided needle biopsy

Cytological assessment of a thyroid mass

This case highlights an uncommon diagnosis encountered in thyroid fine needle aspiration, highlighting differentials based on the clinical features and how cytomorphology can distinguish these.

Needle types used in abdominal cross-sectional interventional radiology: a survey of the Society of Abdominal Radiology emerging technology commission

PURPOSE

To identify commonly used needle types in cross-sectional interventional radiology (CSIR) and to review features and safety profiles of those needles.

METHODS

Members of the Society of Abdominal Radiology (SAR) emerging technologies commission (ETC) on CSIR were sent a 13-question survey about what needles they use for common CSIR procedures: random and targeted solid organ biopsy, ultrasound-guided paracentesis, and ultrasound-guided thyroid fine needle aspiration (FNA). Results were compiled with descriptive statistics, and features of the most commonly used needles were reviewed.

RESULTS

19 surveys were completed (response rate 57.6%, 19/33) from 16 institutions. For solid organ biopsies, the majority of respondents reported using an 18-gauge needle with an automatic firing mechanism and a variable throw length option. The most commonly used needle for both random and targeted biopsies was the Argon BioPince (26.3%, 5/19) The three most commonly used needles for solid organ biopsies all featured automatic firing, variable throw length options, and 18-gauge size. A 5 French Cook Yueh needle was most the most commonly used paracentesis needle (36.8%, 7/19). For thyroid FNA, all respondents used spinal needles, and 25-gauge was the most common size (72.2%, 13/18).

CONCLUSION

Abdominal radiologists use a variety of needles when performing common interventional procedures. Members of the SAR CSIR ETC commonly use automatic, 18-gauge, variable throw length needles for solid organ biopsies, 5 French catheter style needles for paracentesis, and 25-gauge spinal needles for thyroid FNA.

The Risk of Developing Lymphoma among Autoimmune Thyroid Disorder Patients: A Cross-Section Study

Background

Graves' disease (GD) and Hashimoto's thyroiditis (HT) are the most common types of autoimmune thyroid diseases (AITD), and both are characterized by the infiltration of lymphocytes into the thyroid gland. Moreover, autoimmune diseases like HT have a higher risk of developing lymphoma. This study is aimed at assessing the prevalence and association of lymphoma in patients with AITD.

Methods

This cross-sectional study was conducted in King Abdulaziz Medical City, Jeddah, Saudi Arabia. Data were gathered from the medical records of patients aged 18 years or older who developed AITD. A total number of 140 medical records were collected, and 72 patients were included after applying in exclusion criteria. Data on the subtype, clinical-stage, treatment modality, patient status, remission, and relapse were collected for patients who developed lymphoma.

Results

Among 72 patients who developed AITD, HT was diagnosed in 58 (80.6%) patients and GD in 14 (19.4%). Five (7%) patients were diagnosed with lymphoma all of whom had a history of HT. The subtypes of lymphoma were diffuse large B-cell lymphoma (DLBCL 3; 4.2%), follicular lymphoma 1 (1.4%), and Hodgkin's lymphoma 1 (1.4%).

Conclusion

The prevalence of PTL in patients with AITD, specifically HT, was 7%. Most patients developed NHL, with DLBCL being the most common subtype. The onset of lymphoma in this study was lower than reported in the literature. All patients with PTL had HT in their backgrounds. Further national studies are warranted to explore the relationship between the two diseases to provide more insight into the comprehension of this association.

Effectiveness of core needle biopsy in the diagnosis of thyroid lymphoma and anaplastic thyroid carcinoma: A systematic review and meta-analysis

BACKGROUND

Both anaplastic thyroid carcinoma (ATC) and thyroid lymphoma (TL) clinically present as rapidly enlarging neck masses. Unfortunately, in this situation, like in any other thyroid swelling, a routine fine-needle aspiration (FNA) cytology is the first and only diagnostic test performed at the initial contact in the average thyroid practice. FNA, however, has a low sensitivity in diagnosing ATC and TL, and by the time the often "inconclusive" result is known, precious time has evolved, before going for core-needle biopsy (CNB) or incisional biopsy (IB) as the natural next diagnostic steps.

OBJECTIVES

To determine the diagnostic value of CNB in the clinical setting of a rapidly enlarging thyroid mass, via a systematic review and meta-analysis of the available data on CNB reliability in the differential diagnosis of ATC and TL.

METHODS

A PubMed, Embase and Web of Science database search was performed on June 23th 2021. Population of interest comprised patients who underwent CNB for clinical or ultrasonographical suspicion of ATC or TL, patients with a final diagnosis of ATC or TL after CNB, or after IB following CNB.

RESULTS

From a total of 17 studies, 166 patients were included. One hundred and thirty-six were diagnosed as TL and 14 as ATC following CNB. CNB, with a sensitivity and positive predictive value of 94,3% and 100% for TL and 80,1% and 100% for ATC respectively, proved to be superior to FNA (reported sensitivity for TL of 48% and for ATC of 61%). Furthermore, the need for additional diagnostic surgery after CNB was only 6.2% for TL and 17.6% for ATC.

CONCLUSIONS

Immediately performing CNB for a suspected diagnosis of ATC and TL in a rapidly enlarging thyroid mass is more appropriate and straightforward than a stepped diagnostic pathway using FNA first and awaiting the result before doing CNB.

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.

Progressively Enlarging Goiter: Case Reports of Primary Thyroid Lymphoma and Literature Review

Primary thyroid lymphoma (PTL) is an exceptionally rare and highly aggressive potentially curable malignant disease. We report three typical cases of PTL referred to our hospital. All three cases had long history of Hashimoto's thyroiditis, and presented with progressively enlarging neck mass. The first two cases were confirmed by surgical biopsy to be diffuse large B cell lymphoma, and received radiotherapy combined with chemotherapy, or received only chemotherapy. The third case was confirmed by core needle biopsy to be mucosa-associated lymphoid tissue lymphoma, and received radiotherapy. In summary, confirmation of PTL diagnosis is essential for further clinical decisions. Core biopsy should be one of the most important methods to make the diagnosis of PTL, while the use of fine needle aspiration cytology alone is still limited in diagnosing PTL.

Core-Needle Biopsy Does Not Show Superior Diagnostic Performance to Fine-Needle Aspiration for Diagnosing Thyroid Nodules

PURPOSE

To compare the diagnostic performances of fine-needle aspiration (FNA) and core-needle biopsy (CNB) for thyroid nodules according to nodule size.

MATERIALS AND METHODS

This retrospective study included 320 thyroid nodules from 320 patients who underwent both FNA and CNB at outside clinics and proceeded with surgery in our institution between July 2012 and May 2019. According to nodule size, the diagnostic performances of FNA and CNB were calculated using various combinations of test-negatives and test-positives defined by the Bethesda categories and were compared using the generalized estimated equation and the Delong method.

RESULTS

There were 279 malignant nodules in 279 patients and 41 benign nodules in 41 patients. The diagnostic performance of FNA was mostly not different from CNB regardless of nodule size, except for negative predictive value, which was better for FNA than CNB when applying Criteria 1 and 2. When applying Criteria 3, the specificity and positive predictive value of FNA were superior to CNB regardless of size. When applying Criteria 4, diagnostic performance did not differ between FNA and CNB regardless of size. After applying Criteria 5, diagnostic performance did not differ between FNA and CNB in nodules ≥2 cm. However, in nodules ≥1 cm and all nodules, the sensitivity, accuracy, and negative predictive value of CNB were better than those of FNA.

CONCLUSION

CNB did not show superior diagnostic performance to FNA for diagnosing thyroid nodules.

2019 Practice guidelines for thyroid core needle biopsy: a report of the Clinical Practice Guidelines Development Committee of the Korean Thyroid Association

Ultrasound-guided core needle biopsy (CNB) has been increasingly used for the pre-operative diagnosis of thyroid nodules. Since the Korean Society of the Thyroid Radiology published the ‘Consensus Statement and Recommendations for Thyroid CNB’ in 2017 and the Korean Endocrine Pathology Thyroid CNB Study Group published ‘Pathology Reporting of Thyroid Core Needle Biopsy’ in 2015, advances have occurred rapidly not only in the management guidelines for thyroid nodules but also in the diagnostic terminology and classification schemes. The Clinical Practice Guidelines Development Committee of the Korean Thyroid Association (KTA) reviewed publications on thyroid CNB from 1995 to September 2019 and updated the recommendations and statements for the diagnosis and management of thyroid nodules using CNB. Recommendations for the resolution of clinical controversies regarding the use of CNB were based on expert opinion. These practical guidelines include recommendations and statements regarding indications for CNB, patient preparation, CNB technique, biopsy-related complications, biopsy specimen preparation and processing, and pathology interpretation and reporting of thyroid CNB.

Clinical features associated with high pathological grade in primary thyroid lymphoma

This study aimed to identify clinical features associated with high pathological grade (HG) in primary thyroid lymphoma (PTL), through a systematic review and meta-analysis. Electronic databases were searched for studies assessing PTL. Extracted data were age, sex, lymph node involvement, symptoms, lymphocytic thyroiditis, serum tumor markers; the association with HG was assessed by using odds ratio (OR), with a significant p-value<0.05. Twenty-four studies with 1916 PTLs were included. HG was significantly associated with age≤55 (OR = 0.54; p < 0.0001); female sex (OR = 1.31; p = 0.02), lymph node involvement (OR = 2.23; p < 0.00001), compressive symptoms (OR = 2.61; p < 0.0001), absence of lymphocytic thyroiditis (OR = 0.45; p = 0.0002), and increased LDH levels (OR = 4.90; p < 0.00001), but not with age>60 (OR = 0.74; p = 0.24), age>70 (OR = 1.16; p = 0.66), and B symptoms (OR = 1.30; p = 0.54). In conclusion, Age≤55, female sex, lymph node involvement, compressive symptoms and absence of lymphocytic thyroiditis may be predictive factors for HG in PTL. On the other hand, B symptoms does not seem to be associated with pathological grade.

Core Needle Biopsy of the Thyroid: 2016 Consensus Statement and Recommendations from Korean Society of Thyroid Radiology

Core needle biopsy (CNB) has been suggested as a complementary diagnostic method to fine-needle aspiration in patients with thyroid nodules. Many recent CNB studies have suggested a more advanced role for CNB, but there are still no guidelines on its use. Therefore, the Task Force Committee of the Korean Society of Thyroid Radiology has developed the present consensus statement and recommendations for the role of CNB in the diagnosis of thyroid nodules. These recommendations are based on evidence from the current literature and expert consensus.

The role of core-needle biopsy in the diagnosis of thyroid malignancy in 4580 patients with 4746 thyroid nodules: a systematic review and meta-analysis

To evaluate the effectiveness and complications of core-needle biopsy (CNB) compared to fine-needle aspiration (FNA) for diagnosing thyroid malignancy. The Ovid-MEDLINE and EMBASE databases were searched for studies using CNB for diagnosing thyroid malignancy. A meta-analysis was performed to evaluate the diagnostic accuracy, the incidence of non-diagnostic, inconclusive results, and the complications of CNB and FNA. To overcome the heterogeneity, additional analyses based on three, homogeneous inclusion criteria were performed and subgroup analyses were performed. Twenty eligible studies of 4580 patients (4746 nodules) were included. Both CNB and FNA demonstrated a high sensitivity (91 %, 74 %, respectively; p = .053) and specificity (99 %, 100 %, respectively; p = .914). The area under the curve was larger in CNB (0.99) than in FNA (0.94). CNB demonstrated a significantly lower pooled proportion of non-diagnostic (5.5 %; p < .001) and inconclusive results (8.0 %; p < .001) than FNA (22.6 %, 40.2 %, respectively). The complications rate of FNA (0.0 %) was lower than that of CNB (0.01 %), although not significantly (p = .948). This meta-analysis showed variable heterogeneities, i.e., no heterogeneity to considerable heterogeneity. Additional meta-analyses based on three, homogeneous inclusion criteria demonstrated that heterogeneities were reduced, and the results are in agreement with those of all of the included studies. Subgroup analyses have explained the cause of heterogeneity across studies. Both CNB and FNA may be acceptable diagnostic tools for diagnosing thyroid malignancy. CNB may be a complementary diagnostic tool in nodules with initially non-diagnostic and indeterminate results on previous FNA.

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.

Core needle biopsy could reduce diagnostic surgery in patients with anaplastic thyroid cancer or thyroid lymphoma

OBJECTIVE

To evaluate the diagnostic performance of fine needle aspiration (FNA) and core needle biopsy (CNB) in patients with anaplastic thyroid cancer (ATC) or thyroid lymphoma (TL).

METHODS

Between January 2000 and March 2012, 104 patients were diagnosed with ATC or TL by means of ultrasound (US)-guided FNA, CNB, or surgery. This study ultimately included 99 patients with ATC (n = 59) or TL (n = 40). We evaluated the sensitivity and positive predictive value of FNA and CNB for the diagnosis of ATC and TL, and compared the rates of diagnostic surgery between FNA and CNB.

RESULTS

FNA was used in 83 patients, and CNB was used in 32 patients initially (n = 16), after FNA results (n = 8), or simultaneously with FNA (n = 8). CNB achieved sensitivity of 87.5 % (28/32) and positive predictive value of 100.0 % (28/28) for the diagnosis of ATC and TL. The respective values for FNA were 50.6 % (40/79) and 90.9 % (40/44). The rate of diagnostic surgery was significantly lower after CNB (4/32, 12.5 %) than after FNA (28/79, 35.4 %) (p = 0.020).

CONCLUSIONS

CNB was able to reduce unnecessary diagnostic surgery in patients with ATC or TL by virtue of its superior diagnostic sensitivity and positive predictive value compared to FNA.

KEY POINTS

• Diagnostic sensitivity and PPV for CNB were 87.5 % and 100.0 %, respectively. • The respective values for FNA were 50.6 % and 91.0 % for ATC and TL. • Diagnostic surgery rates were reduced after CNB compared to FNA (p = 0.020).

The Role of Core Needle Biopsy and Its Impact on Surgical Management in Patients with Medullary Thyroid Cancer: Clinical Experience at 3 Medical Institutions

BACKGROUND AND PURPOSE

Medullary thyroid carcinoma is an uncommon malignancy that is challenging to diagnose. Our aim was to present our experience using core needle biopsy for the diagnosis of medullary thyroid carcinoma compared with fine-needle aspiration.

MATERIALS AND METHODS

Between January 2000 and March 2012, 202 thyroid nodules in 191 patients were diagnosed as medullary thyroid cancer by using sonography-guided fine-needle aspiration, core needle biopsy, or surgery. One hundred eighty-three thyroid nodules in 172 patients were included on the basis of the final diagnosis. We evaluated the sensitivity and positive predictive value of fine-needle aspiration and core needle biopsy for the diagnosis of medullary thyroid cancer. We compared the rate of a delayed diagnosis, a diagnostic surgery, and surgery with an incorrect diagnosis for fine-needle aspiration and core needle biopsy and investigated the factors related to the fine-needle aspiration misdiagnosis of medullary thyroid cancer.

RESULTS

Fine-needle aspiration showed 43.8% sensitivity and 85.1% positive predictive value for the diagnosis of medullary thyroid cancer; 25.7% (44/171) of patients had a delayed diagnosis, while 18.7% (32/171) underwent an operation for accurate diagnosis, and 20.5% (35/171) underwent an operation with an incorrect diagnosis. Core needle biopsy achieved 100% sensitivity and positive predictive value without a delay in diagnosis (0/22), the need for a diagnostic operation (0/22), or an operation for an incorrect diagnosis (0/22). A calcitonin level of <100 pg/mL was the only significant factor for predicting the fine-needle aspiration misdiagnosis of medullary thyroid cancer (P = .034).

CONCLUSIONS

Core needle biopsy showed a superior sensitivity and positive predictive value to fine-needle aspiration and could optimize the surgical management in patients with medullary thyroid cancer. Because the ability of fine-needle aspiration to diagnose medullary thyroid cancer significantly decreases in patients with serum calcitonin levels of <100 pg/mL, core needle biopsy could be indicated for these patients to optimize their surgical management.

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.

A short review of basic head and neck interventional procedures in a general radiology department

Image-guided interventional procedures provide a safe way to diagnose and treat a variety of head and neck abnormalities. The procedure time is usually short, and most procedures can be performed on an outpatient basis. Knowledge about strengths and weaknesses, efficacy, potential complications, and pitfalls of these procedures allows the best treatment to be chosen for a particular lesion type. This review discusses some of the commonly performed interventional radiology procedures in a general radiology department in the management of patients with neoplastic diseases in the head and neck region.

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.

Use of end-cutting needles in ultrasound-guided biopsy of neck lesions

The management of a neck mass is dictated by its nature, location and extent. Pathological diagnosis by fine needle aspiration cytology (FNAC) or core biopsy is often required before proceeding to definitive treatment. It is not uncommon for the cytology result to come back as inadequate for various reasons. The unique design of the end-cutting biopsy needle in our experience makes it a good choice for use in obtaining both transcutaneous and intraoral biopsy under ultrasound guidance of neck lesions and serves as a useful alternative or adjunct to FNAC. Although there is, as yet, only a limited evidence base about end-cutting in comparison to side-cutting needles, they carry several potential advantages.

KEY POINTS

End-cutting needles are safe to use for lesions close to vital structures. End-cutting needles yield sufficient tissue samples in a single pass. End-cutting biopsy needles are a useful adjunct to FNAC.

Sonographic appearances of mucosa-associated lymphoid tissue lymphoma of the submandibular gland confirmed with sonographically guided core needle biopsy

A 71-year-old man presented with mucosa-associated lymphoid tissue (MALT) lymphoma of the submandibular gland 52 months after initial diagnosis of MALT lymphoma of the lung. Ultrasonography showed a well-demarcated, markedly hypoechoic, heterogeneous solid mass with linear echogenic strands and hypervascularity. Ultrasound-guided core-needle biopsy demonstrated histological findings of MALT lymphoma. Sonographic features of MALT lymphoma of the submandibular gland are characteristic and ultrasound-guided core-needle biopsy may be a suitable replacement for surgical biopsy.

Role of ultrasonography in thyroid disease

Ultrasonography (US) is the single-most valuable imaging modality in the evaluation of the thyroid gland. This review discusses the US appearances of thyroid nodules, emphasizing sonographic features associated with potentially malignant or, at the other end of the spectrum, likely benign nodules. Diffuse thyroid abnormalities have also been reviewed. The technique of ultrasound-guided fine-needle aspiration biopsy and the emerging role of elastography in characterizing thyroid nodules have also been addressed.

Primary thyroid lymphoma: a review of recent developments in diagnosis and histology-driven treatment

PURPOSE OF REVIEW

Primary thyroid lymphoma (PTL) is a rare but clinically important malignancy of the thyroid. This article reviews the diagnosis, histologic subtypes, pathogenesis, and treatment of PTL, with the objective of optimizing diagnosis and management of the disease.

RECENT FINDINGS

Recent studies have shed light on the clinicopathologic features of the histologic subtypes of PTL. Analysis of the pathogenesis of PTL indicates that both antigenic stimulation in the setting of Hashimoto's thyroiditis and aberrant somatic hypermutation may play a role. The first large, population-based study of PTL indicated that age, stage, histologic subtype, and treatment modality have prognostic implications. The U.S. Food and Drug Administration approval of rituximab for non-Hodgkin's lymphoma has improved standard chemotherapeutic options, as data on efficacy in nodal and other extranodal lymphomas have been extrapolated to PTL.

SUMMARY

Advances in the understanding of the histologic subtypes of PTL have led to more accurate diagnosis and tailored treatments. The introduction of a new chemotherapeutic agent has expanded the treatment paradigm for PTL. Important prognostic indicators of survival for patients with PTL have been confirmed in the first population-based study. This article emphasizes current diagnostic and treatment approaches and discusses the potential for future developments.

US-guided fine-needle aspiration of thyroid nodules: indications, techniques, results

Fine-needle aspiration (FNA) biopsy of thyroid nodules is minimally invasive and safe and is usually performed on an outpatient basis. However, the optimal application of FNA requires not only technical skill but also an awareness of the limitations of the procedure, the indications for its use, the factors that affect the adequacy of the biopsy specimen, and the postprocedural management strategy. Ultrasonographic (US) features that are considered indications for FNA include single and multiple thyroid nodules. The results of FNA biopsy are operator dependent. In addition, the results may be affected by the lesion characteristics, the accuracy of lesion and needle localization, the method of guidance, the number of aspirated samples, the needle gauge, the aspiration technique, and the presence or absence of on-site facilities for immediate cytologic examination. With regard to postprocedural management, nodules that are diagnosed as benign on the basis of an adequate FNA specimen should be monitored with follow-up US. Circumstances that necessitate repeat FNA include sample inadequacy, nodule enlargement, cyst recurrence, or clinical or imaging findings that arouse suspicion about the presence of a malignancy even when cytologic findings in the biopsy specimen indicate benignity. Supplemental material available at radiographics.rsnajnls.org/cgi/content/full/28/7/1869/DC1.