Sentinel Lymph Node Biopsy May Be Used to Support the Decision to Perform Modified Radical Neck Dissection in Differentiated Thyroid Carcinoma

Frozen Section in Diagnosis of Thyroid Swelling: Does It Still Have Role?

Purpose The present study correlates the frozen section diagnosis of thyroid swelling with the histopathological diagnosis and assesses the expression of immunohistochemical markers in malignant thyroid tumours. Also, the study aims to analyse the accuracy and limitations of the frozen section as an intraoperative tool for the diagnosis of thyroid swellings. Method Fifty-three cases of thyroid swelling were included in the study. Frozen section reports were classified as benign, malignant and deferred. A correlation between frozen section and histopathology examination (HPE) reports has been evaluated. The malignant cases confirmed on HPE were subjected to Immunohistochemistry (IHC) with TTF-1, Thyroglobulin, and CK-7. Results Among the 53 patients, 45 (84.9%) were females, and the majority were younger than 40 years (60.37%). On frozen section majority, 42 (79.25%) were benign, while a definitive diagnosis of malignancy was made in six cases (11.32%). On the frozen section, there were no false-positive cases, six true-positive cases, one false-negative case and 46 true-negative cases, with a sensitivity of 85.71%, specificity of 100%, the positive predictive value of 100%, the negative predictive value of 97.87% and diagnostic accuracy of 98.11% respectively. All the six papillary carcinomas and one follicular carcinoma showed immunoreactivity of tumor cells to TTF 1, CK 7 and Thyroglobulin. Conclusion There was a strong correlation between the frozen section and histopathological diagnosis. Still, it is not recommended in routine use for intraoperative diagnosis of thyroid swelling because of various limitations and the high diagnostic accuracy of FNAC. Adequate histopathologic diagnosis of thyroid disease is based on extensive subsampling of the specimen, which is not possible during an intraoperative frozen section procedure. If the frozen section is used, its limitations must be recognized, preferably based on first-hand data.

Utility of sentinel lymph node biopsy in papillary thyroid microcarcinoma

PURPOSE

There are many studies on sentinel lymph node (SLN) biopsy in thyroid carcinoma but SLN biopsy (SLNB) in papillary thyroid carcinoma (PTC) remains open to debate. Therefore in this retrospective study, the usefulness of SLNB in thyroid carcinoma patients who had micro-PTC without cervical lymphadenopathy was assessed.

METHODS

SLNB was performed in 114 patients who were diagnosed with micro-PTC in a single lobe without palpable or ultrasound-detected lymph node at the tertiary center between January 2012 and December 2013. After SLNB, all patients underwent total thyroidectomy and central neck dissection or thyroid lobectomy and central neck dissection of the single side.

RESULTS

SLNs were identified in 112 of 114 patients with 41 positive SLNs and 71 negative SLNs on intraoperative frozen sections. However, eight negative patients were found to be positive in the final pathology. Sentinel node identification rate and false negative value of SLNB were 98.2% and 11.3%, respectively. In the univariate analysis, higher lymph node metastasis was detected in men than in women. Higher detection number of SLN showed higher probability of lymph node metastasis.

CONCLUSION

SLNB may be helpful in papillary thyroid cancer, especially in male patients. Also, it is useful for the staging of nodal status and clearance of persistent disease.

The Diagnostic Accuracy of One-Step Nucleic Acid Amplification for Lymph Node Metastases of Papillary Thyroid Carcinoma： A Systematic Review and Meta-Analysis

BACKGROUND

One-step nucleic acid amplification (OSNA) analysis is a molecular diagnostic technique for lymph node metastases (LNMs) by quantifying cytokeratin 19(CK 19) mRNA. We aim to evaluate the intraoperative diagnostic accuracy of OSNA assay for LNMs of papillary thyroid carcinoma (PTC).

METHODS

PubMed, Embase, Cochrane Library, and Web of Science databases were searched to retrieve related literature. A meta-analysis was performed using STATA11.0, Meta-Disc 1.4 and RevMan 5.3.

RESULTS

This meta-analysis included six studies involving 987 lymph nodes from 194 patients. The pooled sensitivity, specificity, and area under the summary receiver-operating characteristic curve (AUC) of OSNA for detecting LNM were 0.88, 0.90, and 0.95, respectively.

CONCLUSION

OSNA assay is an accurate molecular diagnosis for intraoperative detection of lymph node metastasis in PTC.

Clinical feasibility of imaging with indocyanine green combined with carbon nanoparticles for sentinel lymph node identification in papillary thyroid microcarcinoma

BACKGROUND

Although several previous studies demonstrated the feasibility and efficacy of indocyanine green (ICG) for thyroid cancer surgery, ICG was administered through venous injection and focused on parathyroid gland protection. We thus aimed to study the feasibility of imaging using ICG combined with carbon nanoparticles (CNs) in the identification of sentinel lymph nodes (SLNs) in patients diagnosed with papillary thyroid microcarcinoma (PTMC).

METHODS

Two approaches were applied to detect lymph nodes in PTMC surgery. Patients were randomized into 2 groups. ICG and CNs were injected into the thyroid in Group A. In Group B, only CNs was injected. Black-stained or fluorescent nodes observed using near-infrared fluorescence imaging systems were defined as SLNs. SLN and central lymph node (CLN) dissection was completed in both groups. The pathological and postoperative outcomes were compared between 2 groups.

RESULTS

There were 40 patients in Group A and 60 in Group B. A total of 138 SLNs were identified; 72 and 66 SLNs were detected and dissected in Groups A and B, respectively. The number of SLNs identified (per patient) in Group A was higher than that in Group B (P = .027). The number of harvested CLNs was 161 and 192 in Groups A and B, respectively, out of which 45 and 48 lymph nodes with metastasis were confirmed by permanent pathology. The CLN metastatic rate in Group A was higher than that in Group B (P = .048).

CONCLUSION

Imaging using ICG combined CNs is feasible and safe for SLN identification in PTMC patients. Compared with using only CNs, more SLNs can be removed and more metastatic lymph nodes can be confirmed when using the combined method. Although the combined method appears to accurately stage tumors, further research is needed.

Sentinel Lymph Node Biopsy in Small Papillary Thyroid Cancer: A Meta-analysis

PURPOSE

The aim of this study was to compare reported results on available techniques for sentinel lymph node detection rate (SDR) in papillary thyroid cancer (PTC).

METHODS

The MEDLINE database was searched via a PubMed interface to identify original articles regarding sentinel lymph node biopsy (SNB) in thyroid cancer. Studies were stratified according to the sentinel lymph node (SLN) detection technique: vital-dye (VD), Tc-nanocolloid planar lymphoscintigraphy with the use of intraoperative hand-held gamma probes (LS), both Tc-nanocolloid planar lymphoscintigraphy with intraoperative use of hand-held gamma probe and VD (LS + VD), Tc-nanocolloid planar lymphoscintigraphy with the additional contribution of preoperative SPECT/CT, and intraoperative use of hand-held gamma probe (LS-SPECT/CT). Pooled SDR values were presented with a 95% confidence interval (CI) for each SLN detection techniques. A Z-test was used to compare pooled SDR estimates. False-negative rates were summarized for each method.

RESULTS

Forty-five studies were included. Overall SDRs for the VD, LS, LS + VD, and LS-SPECT/CT techniques were 83% (95% CI, 77%-88%; I = 78%), 96% (95% CI, 90%-98%; I = 68%), 87% (95% CI, 65%-96%; I = 75%), and 93% (95% CI, 86%-97%; I = 0%), respectively. False-negative rates were 0% to 38%, 0% to 40%, 0% to 17%, and 7% to 8%, respectively.

CONCLUSIONS

In patients with PTC, Tc-nanocolloids offer a higher SDR than that of the VD technique. The addition of SPECT/CT improved identification of metastatic SLNs outside the central neck compartment.

Sentinel lymph node biopsy in small papillary thyroid cancer. A review on novel surgical techniques

PURPOSE

Sentinel lymph node biopsy (SNB) in patients with papillary thyroid carcinoma (PTC) and negative for clinically neck lymph node metastatic involvement (N0) has emerged as a promising minimally invasive procedure to detect metastatic nodes.

METHODS

The MEDLINE database was searched via the PubMed interface on 10 January 2018 for the MeSH headings "sentinel lymph node biopsy" and "thyroid carcinoma".

RESULTS

Vital blue dye, radioisotope, and the combination of both techniques are used in PTC patients. These methods and the emerging role of SPECT/CT are discussed in this review. The sentinel lymph node (SLN) identification rates ranged from 0 to 100% for blue dye, 83 to 100% for radioisotopes, and 66 to 100% for the combination of both techniques, respectively.

CONCLUSIONS

SNB based on radioisotope technique with the use of intraoperative gamma-probe is an accurate and safe method that allows the highest SLN detection rate. There is sufficient evidence to propagate the increasing use of SNB procedure that has the potential to avoid prophylactic lymph node surgery in patients clinically N0.

Role of sentinel node in differentiated thyroid cancer: a prospective study comparing patent blue injection technique, lymphoscintigraphy and the combined technique

PURPOSE

The purpose of the present study was to evaluate the feasibility and reproducibility of the sentinel lymph node (SLNs) biopsy in differentiated thyroid cancer using patent blue injection, lymphoscintigraphy and the combined techniques.

METHODS

Between January 2011 and January 2013, 82 consecutive patients were enrolled in our prospective multicentre study. Inclusion criteria were 18 years of age, preoperative diagnosis of differentiated thyroid carcinoma, no evidence of lymph node enlargement and multifocal neoplasm. To investigate the benefits of each procedure, all patients underwent total thyroidectomy plus central compartment lymphadenectomy, and in all cases, the SLN was identified via one of three techniques using the same protocol.

RESULTS

Lymphoscintigraphy was used in five patients, patent blue injection was used in 40 patients, and a combined technique was used in 40 patients to identify sentinel lymph nodes (SLN). SLNs were identified in 61 cases. In the patent blue injection technique, the sensitivity, specificity and false negative rates were 88.9, 94.4 and 3.8%, respectively. In the lymphoscintigraphy technique, the percentages of sensitivity and specificity were 100%, and the percentage false negative was 0%. For the combined techniques, the corresponding values were, respectively, 69.2, 90, and 17.4%. Metastases were detected in nine cases of lateral-cervical nodes, ipsilateral tumour metastases were observed in eight cases, and contralateral tumour metastasis was observed in one case.

CONCLUSION

Additional well-designed randomized studies are needed to validate and further optimize the SLN biopsy in patients with differentiated thyroid cancer.

Patterns and clinical significance of cervical lymph node metastasis in papillary thyroid cancer patients with Delphian lymph node metastasis

Although the roles of Delphian lymph node (DLN) metastasis in papillary thyroid cancer (PTC) have been previously reported, there are still limited data on correlations of clinicopathologic factors with DLN metastasis and unique patterns of cervical node subsite metastasis in PTC patients with DLN metastasis. We retrospectively reviewed medical records of 320 patients with a diagnosis of PTC who underwent primary surgery. Clinicopathologic features and DLN metastasis patterns were analyzed for predicting extensive cervical lymph node metastasis. Both univariate and multivariate Cox regression analyses were used to identify independent factors for cervical lymph node metastasis. DLN metastasis was significantly associated with multifocality, tumor size > 1 cm, extrathyroid extension, BRAF^V600E mutation, central neck node metastasis (CNNM), and lateral neck nodes metastases. Patients with DLN metastasis had more lymph node metastases in the central compartment. CNNM number and tumor size > 1 cm were independent risk factors for DLN metastasis. DLN metastasis was highly predictive of lateral lymph node metastasis with moderate sensitivity and high specificity. DLN metastasis is associated with several poor prognostic factors, including extensive cervical lymph node metastasis, and can serve as a predictor of advanced PTC. The presence of DLN metastasis should prompt surgeons to perform an aggressive surgery approach.

The Role of Central Neck Lymph Node Dissection in the Management of Papillary Thyroid Cancer

Papillary thyroid cancer (PTC) is the most common thyroid malignancy, and cervical nodal metastases are frequent at presentation. The most common site for nodal metastases from PTC is the central compartment of the ipsilateral neck in the paratracheal and pretracheal regions. The decision to resect these lymph nodes at the time of thyroidectomy often depends on if nodes with suspected malignancy can be identified preoperatively. If nodal spread to the central neck nodes is known, then the consensus is to remove all nodes in this area. However, there remains significant controversy regarding the utility of removing central neck lymph nodes for prophylactic reasons. Herein, we review the potential utility of central neck lymph node dissection as well as the risks of performing this procedure. As well, we review the potential of molecular testing to stratify patients who would most benefit from this procedure. We advocate a selective approach in which patients undergo clinical neck examination coupled with ultrasound to detect any concerning lymph nodes that warrant additional evaluation with either fine needle aspiration or excisional biopsy in the operating room. In lieu of clinical lymphadenopathy, we suggest the use of patient and disease characteristics as identified by multiple groups, such as the American Thyroid Association and European Society of Endocrine Surgeons, which include extremes of ages, large primary tumor size, and male gender, when deciding to perform central neck lymph node dissection. Patients should be educated on the potential long-terms risks versus the lack of known long-term benefits.

Robotic thyroidectomy and cervical neck dissection for thyroid cancer

A robotic approach for thyroid surgery was developed to overcome the limitations of endoscopic thyroidectomy and provide many technical advantages. This approach facilitates the surgeon's control through a magnified three-dimensional view, decreased tremor, and freedom of motion with articulated instruments. Robotic thyroidectomy is safe and technically feasible in patients with well-differentiated, low-risk thyroid cancer. Furthermore, robotic thyroidectomy may become a good surgical alternative option for patients with more advanced thyroid cancer. Our modified bilateral axillo-breast approach (BABA) for central and lateral cervical neck lymph node (LN) dissection has yielded excellent surgical outcomes as an open procedure. The incorporation of robotics in thyroid cancer surgery will continue to evolve, and the surgical indications for robotic thyroidectomy will continue to expand. Further analyses that include long-term outcomes and randomized comparative trials remain important.

Utility of sentinel lymph node biopsy for thyroid cancer: a comprehensive review

Sentinel lymph node biopsy (SLNB) is a minimally invasive lymphatic mapping technique, used to identify lymph node micrometastases and stage multiple cancer types. Despite the performance of SLNB for thyroid cancer having been under study since 1998, its role has remained controversial. The objective of this review is to summarize current research reporting on SLNB for thyroid cancer, focusing on recent studies of its application to differentiated thyroid cancer. The technique and potential benefits of SLNB are reviewed with regards to its ability to identify lymph node metastases, aid in cancer prognostication, and direct surgical and medical treatment.

The Utility of Sentinel Lymph Node Biopsy in Papillary Thyroid Carcinoma with Occult Lymph Nodes

Background

The sentinel lymph node (SLN) is defined as the first draining node from the primary lesion, and it has proven to be a good indicator of the metastatic status of regional lymph nodes in solid tumors. The aim of this study was to evaluate the clinical application of SLN biopsy (SLNB) in papillary thyroid carcinoma (PTC) with occult lymph nodes.

Methods

From April 2006 to October 2012, 212 consecutive PTC patients were treated with SLNB using carbon nanoparticle suspension (CNS). Then, the stained nodes defined as SLN were collected, and prophylactic central compartment neck dissection (CCND) followed by total thyroidectomy or subtotal thyroidectomy were performed. All the samples were sent for pathological examination.

Results

There were 78 (36.8%) SLN metastasis (SLNM)-positive cases and 134 (63.2%) SLNM-negative cases. The sensitivity, specificity, positive and negative predictive values, and false-positive and false-negative rates of SLNB were 78.8%, 100%, 100%, 84.3%, 0%, and 21.2%, respectively. The PTC patients with SLNM were more likely to be male (48.2% vs. 32.7%, p = 0.039) and exhibited multifocality (52.6% vs. 33.3%, p = 0.025) and extrathyroidal extension (56.7% vs. 33.5%, p = 0.015). A greater incidence of non-SLN metastases in the central compartment was found in patients with SLNM (41/78, 52.6%) than in those without SLNM (21/134, 15.7%; p < 0.05). However, the SLNM-negative PTC patients with non-SLN metastases were more likely to be male (37.9% vs. 9.5%, p < 0.05).

Conclusions

The application of SLNB using CNS is technically feasible, safe, and useful, especially for male patients with co-existing multifocality and extrathyroidal extension. However, the sensitivity of SLNB must be improved and its false-negative rate reduced before it can be a routine procedure and replace prophylactic CCND. More attention should be paid to PTC patients (especially males) without SLNM for signs of non-SLN metastases.

Neck dissection with cervical sensory preservation in thyroid cancer

Thyroid cancer is the most common endocrine malignancy. Recently, controversy has focused on the management of lymph node metastases, which represent approximately 90% of disease recurrences and may require considerable time, effort, and resources to diagnose and treat. Neck dissections play an essential role in the management of head and neck cancer. A modified radical neck dissection (MND) refers to resection of the lymph nodes in levels II through V and often including the central nodes in level VI. When performing modified neck dissection, we recommend to protect more reserved cervical plexus. The purpose is to better protect patient's neck skin feeling.

Surgery of lymph nodes in papillary thyroid cancer

Optimal treatment for differentiated thyroid carcinoma is controversial with respect to the extent of thyroid resection, the extent and technique of nodal dissection and use of prophylactic radioiodine treatment. Postoperative complications, such as recurrent laryngeal nerve injury and definitive hypoparathyroidism, have carried great weight in the discussion regarding how radical the surgical treatment should be. The discussion of whether total thyroidectomy or lesser procedures should be the treatment for thyroid carcinomas has been protracted. Now, reasonable agreement exists that total thyroidectomy is the best treatment and the focus of the discussion has moved to the treatment of lymph nodes. At the time of diagnosis, node metastases are a common finding in patients with differentiated thyroid cancer, in particular papillary carcinoma. The argument supporting a radical approach to lymph node excision is that the presence of node metastases increases the recurrence rate. Advocates for the conservative approach believe that little association exists between node metastases and death from thyroid carcinoma. This paper reviews relevant medical literature published in the English language on surgery of lymph nodes in differentiated thyroid cancer with well-controlled trials. Searches were last updated in June 2006.

Surgical management of well-differentiated thyroid carcinoma in children and adolescents: 33 years of experience of a single institution in Serbia

Well-differentiated thyroid carcinoma in children and adolescents is rare but demonstrates aggressive behavior. Gross lymph node metastases and distant metastases are common upon first clinical presentation. During a 33-year period (1981-2014) at the Institute of Oncology and Radiology of Serbia, 62 children and adolescents underwent surgery due to well-differentiated thyroid carcinoma. Mean age was 16.7 (range 7-21) years. At the time of diagnosis 6% of patients had lung metastases. Total thyroidectomy or completion thyroidectomy was performed for all patients followed by central neck dissection and frozen section examination of jugular-carotid compartments. Median follow-up was 10.9 (range 0.69-33.05) years and median tumor size was 20 (range 2-60) mm. Papillary carcinoma was found in 96%, and follicular and Hürthle cell carcinoma in 2% of patients. Multifocal tumors were found in 50% and capsular invasion in 60% of patients. Lymphonodal metastases in either central or lateral neck compartments were found in 73% of patients. Multifocality and capsular invasion were significantly more frequent in patients less than 16 years of age (both p < 0.01). Median disease-free interval had not been reached and overall survival rate was 100%. Well-differentiated thyroid carcinoma in children and adolescents is characterized by a high rate of loco-regional aggressiveness, multifocality, capsular invasion, lymph node metastases and distant metastases at the time of diagnosis. Adequate surgical approaches should be performed for both primary and recurrent disease in young patients with well-differentiated thyroid carcinoma in order to achieve loco-regional disease control and longer disease-free survival.

Lymphatic drainage, regional metastases and surgical management of papillary thyroid carcinoma arising in pyramidal lobe--a single institution experience

Papillary thyroid carcinoma (PTC) arising in pyramidal lobe (PL) is very rare. The aim of this study was to determine the incidence of single PTC focus in PL and its lymphonodal metastases, as well as to present a single surgeon experience in management of PL PTC. We performed a retrospective analysis of records of all patients surgically treated for PTC in our institution from year 2003 to 2013. Only patients with single PTC focus in PL were included. Out of total 753 patients, majority (66.52%) had PTC focus in one of the lobes, while only 3 patients (0.4%) had solitary PTC focus in PL. They were all females, aged 36, 41 and 22. During surgery, methylene-blue dye was injected peritumorally. After frozen section analysis of excised PL and isthmus and confirmation of malignancy, we performed total thyroidectomy with central neck dissection, as well as sentinel lymph node biopsy in both jugulo-carotid regions. Pathology showed encapsulated PTC stage T1 and solitary metastasis in Delphian lymph node of the youngest patient. All patients were disease free in the follow-up. PTC single focus in PL is very rare and only individual experiences can be discussed regarding the extent of the surgery.

Thyroglobulin in the washout fluid of lymph-node biopsy: what is its role in the follow-up of differentiated thyroid carcinoma?

BACKGROUND

The clinical evaluation of enlarged local lymph nodes (LNs) is difficult at the beginning and throughout the follow-up of differentiated thyroid carcinoma (DTC). Although the examination of samples collected from LNs by fine-needle aspiration biopsy cytology (FNAB-C) is extremely specific for the diagnosis of metastases, its sensitivity is low, especially in paucicellular samples.

SUMMARY

The measurement of thyroglobulin (Tg) in the fine-needle aspiration biopsy (FNAB) washout fluid (FNAB-Tg) increases the diagnostic performance of cytology to up to 100% sensitivity and specificity. However, the application of FNAB-Tg is currently hindered by the absence of methodological standardization, a lack of definite cutoff points, and the ongoing debate regarding its accuracy in nonthyroidectomized patients, those with elevated serum Tg, and those with circulating anti-Tg antibodies.

CONCLUSION

FNAB-Tg improves the diagnostic performance of FNAB-C in LN metastases, even when the latter is unable to diagnose the metastases. For that reason, FNAB-Tg should be included in the monitoring of DTC.

Frozen section analysis and sentinel lymph node biopsy in well differentiated thyroid cancer

Background

The aim of this study is to prospectively review the role of sentinel lymph node (SLN) biopsy in the management of well differentiated thyroid carcinoma (WDTC), and to determine the efficacy of intraoperative frozen section analysis at detecting SLN metastasis and central compartment involvement.

Methods

The SLN biopsy protocol using 1% methylene blue was performed in 300 patients undergoing thyroidectomy for WDTC. A limited pretracheal central compartment neck dissection (CCND) was performed on all patients. Lymph nodes staining blue were considered as SLN’s. Both frozen and permanent section analyses were performed.

Results

SLN’s with metastasis were found in 14.3% (43/300) of cases. Of this, 11% (33/300) were positive on intraoperative frozen section analysis. Frozen section results failed in predicting central compartment involvement in 15 cases (5%) whereas central neck compartment involvement was missed in 5 cases (1.7%) when based on permanent section results. On frozen section analysis, the sensitivity, specificity, positive predictive value and negative predictive value (95% CI) of our SLN biopsy technique aiming to remove all disease from the central compartment was 68.8% (53.6-80.9), 100% (98.1-100), 100% (87.0-100) and 94.4% (90.7-96.7) respectively with P < 0.0001. On permanent section analysis, the values were 89.6% (76.6-96.1), 100% (98.1-100), 100% (89.8-100), and 98.1% (95.3-99.3) with P < 0.0001.

Conclusion

This data series demonstrates that patients with WDTC have positive SLN’s in 14.3% of cases. Moreover, when the SLN’s are negative for metastasis on frozen section, the central compartment was disease-free in 94.4% of cases. Finally, this study shows that 23.3% of positive SLN’s were false negatives on intraoperative frozen section. According to this data, SLN involvement is an accurate predictor of central compartment metastasis, however surgeons should use caution when relying on intraoperative frozen section to determine whether to perform a CCND.

SPECT/CT sentinel lymph node identification in papillary thyroid cancer: lymphatic staging and surgical management improvement

PURPOSE

Lymphadenectomy in papillary thyroid carcinoma (PTC) continues to be controversial. A better staging method is needed to provide adequate individual surgical treatment. SPECT/CT lymphoscintigraphy and sentinel lymph node (SLN) biopsy may improve lymphatic staging and surgical treatment. Our main objectives were to describe the lymphatic drainage of PTC using lymphoscintigraphy, to evaluate the lymphatic spread (comparing SLN and lymphadenectomy results) and to analyse the impact of SLN identification in surgery.

METHODS

We prospectively studied 24 consecutive patients with PTC (19 women; mean age 52.7 years, range 22-81 years). The day before surgery, lymphoscintigraphy with ultrasound-guided intratumoral injection ((99m)Tc-nanocolloid, 148 MBq) was performed, obtaining planar and SPECT/CT images. All patients underwent total thyroidectomy, SLN biopsy (hand-held gamma probe) with perioperative analysis, central compartment node dissection, or laterocervical lymphadenectomy if perioperative stage N1b or positive SLNs in this lymphatic basin.

RESULTS

Lymphoscintigraphy revealed at least one SLN in 19 of 24 patients (79 %) on planar and SPECT/CT images, and in 23 of 24 patients (96 %) during surgery using a hand-held gamma probe. Lymph node metastases were detected with classical perioperative techniques (ultrasound guidance and surgical inspection) in 3 of 24 patients, by perioperative SLN analysis in 10 of 23, and by definitive histology in 13 of 24. The false-negative (FN) ratio for SLN was 7.7 % (one patient with bulky lymph nodes). The FN ratio for perioperative frozen sections was 15.4 % (two patients, one with micrometastases, the other with bilateral SLN). Lymphatic drainage was only to the central compartment in 6 of 24 patients (3 of the 6 with positive SLNs for metastases), only to the laterocervical basin in 5 of 24 patients (all unilateral, 2 of 5 positive SLNs) and to the central and laterocervical compartments in 12 of 24 patients (6 of 12 and 3 of 12 positive SLNs, respectively).

CONCLUSION

Lymphoscintigraphy reveals the lymph node drainage in a high proportion of patients. It detects laterocervical drainage in a significant percentage of patients, allowing the detection of occult lymph node metastases and improving the surgical management in PTC.

Unilateral follicular variant of papillary thyroid carcinoma with unique KRAS mutation in struma ovarii in bilateral ovarian teratoma: a rare case report

Background

Struma ovarii (SO) is a rare form of ovarian mature teratoma in which thyroid tissue is the predominant element. Because of its rarity, the differential diagnosis between benign and malignant SO has not been clearly defined. It is believed that malignant transformation of SO has similar molecular features with and its prognosis corresponds to that of malignant tumors originating in the thyroid.

Case presentation

We report 35-year-old woman with bilateral ovarian cysts incidentally detected by ultrasound during the first trimester of pregnancy. Four months after delivery of a healthy child without complication she was admitted to the hospital for acute abdominal pain. Laparoscopic left adnexectomy was performed initially in a regional hospital; right cystectomy was done later in a specialized clinic. Intraoperative frozen section and a final pathology revealed that the cyst from the left ovary was composed of mature teratomatous elements, normal thyroid tissue (>50%) and a non-encapsulated focus of follicular variant of papillary thyroid carcinoma (PTC).

Normal and cancerous thyroid tissues were tested for BRAF and RAS mutations by direct sequencing, and for RET/PTC rearrangements by RT-PCR/Southern blotting. A KRAS codon 12 mutation, the GGT → GTT transversion, corresponding to the Gly → Val amino acid change was identified in the absence of other genetic alterations commonly found in PTC.

Conclusion

To the best of our knowledge, this is the first time this mutation is described in a papillary thyroid carcinoma arising in struma in the ovarii. This finding provides further evidence that even rare mutations specific for PTC may occur in such tumors. Molecular testing may be a useful adjunct to common differential diagnostic methods of thyroid malignancy in SO.

The efficacy of lateral neck sentinel lymph node biopsy in papillary thyroid carcinoma

BACKGROUND

Although occult lymph node metastasis to the lateral neck compartment is common in papillary thyroid carcinoma, the incidence and patterns of lateral neck node metastasis in papillary carcinoma are not known. We hypothesized that sentinel lymph node biopsy (SLNB) with radioisotope in the detection of occult lateral neck node metastasis would be useful in characterizing metastasis in papillary carcinoma.

METHODS

Ninety-four patients with papillary thyroid carcinoma were included from June 2009 to March 2010 for lateral neck SLNB. Preoperative lymphoscintigraphy was obtained after intratumoral injection of a (99m)Tc-tin colloid under ultrasound guidance. Total thyroidectomy or lobectomy preceded SLN detection to avoid radioactivity interference with the primary tumor, after which SLNB was performed in the lateral neck nodes. In the cases where metastasis was detected in SLNs upon frozen biopsy, an immediate modified radical neck node dissection was performed.

RESULTS

A total of 174 SLNs were identified in 60 patients (63.8%). The identification rate of the SLNs with isotope increased with time. Sentinel lymph node metastasis was found in 19 patients (31.7%). This clinically occult metastasis was only related to the total number of metastatic LNs in the central compartment. Patient age, gender, tumor size, location, extent of tumor invasion, multiplicity, and presence of thyroiditis were not related to metastasis in the lateral compartment. Detection of lateral neck SLNs upon biopsy with radioisotope was also feasible in level II and contralateral neck.

CONCLUSIONS

Sentinel lymph node biopsy is a useful method for evaluating the occult lateral neck lymph node status in patients with papillary thyroid carcinoma, especially in the cases of central neck node metastasis.

Management of lateral cervical metastases in papillary thyroid cancer: patterns of lymph node distribution

In this article we discuss the management of lateral cervical lymph node metastases in papillary thyroid cancer (PTC). We conducted a retrospective analysis of cases of PTC at our tertiary academic medical center involving 32 patients who underwent 39 neck dissections for the management of lateral cervical metastases from 2000 to 2007. Of these patients, 18 underwent primary neck dissections at the time of thyroidectomy after fine-needle aspiration biopsy confirmed the PTC. Secondary neck dissections for delayed metastases were performed in 14 patients who had previously undergone thyroidectomy for confirmed PTC. All 32 patients had positive nodes in at least one level. Our results highlight the high incidence of multilevel cervical metastasis associated with PTC and suggest the importance of including level II-B (submuscular recess) when performing a neck dissection; the upper posterior triangle (level V-A) is less likely to harbor occult tumor. Lateral neck metastasis from PTC is common and predictable; locoregional control is improved with a formal, comprehensive neck dissection at the time of thyroidectomy.

Surgical management of primary thyroid carcinoma arising in thyroglossal duct cyst: an experience of a single institution in Serbia

Thyroglossal duct cyst (TDC) carcinoma is a comparable rare entity and treatment strategies have not been standardized. Here, we report a favorable outcome of TDC carcinoma patients based on our therapeutic strategy. Twelve patients with TDC carcinoma treated in our department from 1986 to 2012 were enrolled. Ten patients underwent Sistrunk's procedure in other institutions and referred to our institution for re-operation after the diagnosis of TDC carcinoma and the remaining two underwent initial surgery in our institution. Eleven patients were diagnosed as papillary and one as follicular carcinoma originating from TDC. We performed total thyroidectomy for 11, and limited thyroidectomy for one patient. Three patients (25%) had carcinoma lesions in the thyroid. We routinely dissected level I bilaterally and 6 of 11 patients (55%) with papillary carcinoma-type TDC carcinoma had metastasis. Level II/III nodes were biopsied and if positive, we performed level II-IV dissection. Of the 5 patients positive for level II/III, 2 were also positive for level IV. For the 3 patients with synchronous carcinoma in the thyroid, we performed level VI dissection and two had metastasis in this level. To date, 1 patient showed a recurrence to the lung, but none of the patients in our series died of carcinoma. For surgery of TDC carcinoma, Sistrunk's procedure, total thyroidectomy with level I dissection is mandatory. Whether level II-IV dissection is performed depends on pathology of biopsied level II/III nodes. Level VI dissection is also recommended especially when carcinoma lesions are pre/intra operatively detected in the thyroid.

Clinical efficacy of sentinel lymph node biopsy using methylene blue dye in clinically node-negative papillary thyroid carcinoma

BACKGROUND

Sentinel lymph node biopsy (SLNB) has recently been used to detect occult lymph node metastases. The aim of this study was to assess the feasibility and clinical efficacy of SLNB in the treatment of clinically node-negative papillary thyroid carcinoma.

METHODS

A total of 114 consecutive patients with clinically node-negative papillary thyroid carcinoma were enrolled and underwent SLNB. After injection of 1% methylene blue around the tumors, blue-stained sentinel lymph nodes (SLN) were collected from the central compartments. All the patients underwent total thyroidectomy with bilateral central compartment neck dissection after SLNB.

RESULTS

SLN were identified in 84 (73.7%) of the 114 patients. Of these 84 patients, 24 (28.6%) had metastases in the SLN. Among the 60 patients who had no metastases in their SLN in frozen biopsy samples, seven had metastatic foci in their SLN in the permanent biopsy samples and six had metastases in their non-SLN samples. Central compartment lymph node metastases were detected in 11 of the 30 patients in whom SLN were not identified. Thus, the sensitivity, specificity, and positive and negative predictive values of SLNB were 64.9, 100, 100, and 78.3%, respectively. The false-positive and false-negative rates were 0 and 35.1%, respectively. The detection of SLN led to no major complications.

CONCLUSIONS

SLNB using methylene blue in papillary thyroid carcinoma is a safe and technically feasible procedure. However, it is of limited use in the management of clinically node-negative papillary thyroid carcinoma because of low sensitivity and a high false-negative rate.

Sentinel lymph node biopsy is unsuitable for routine practice in younger female patients with unilateral low-risk papillary thyroid carcinoma

Background

Sentinel lymph node (SLN) biopsy has been used to assess patients with papillary thyroid carcinoma (PTC). To achieve its full potential the rate of SLN identification must be as close to 100 percent as possible. In the present study we compared the combination of preoperative lymphoscintigraphy scanning by sulfur colloid labeled with 99 m Technetium, gamma-probe guided surgery, and methylene blue with methylene blue, alone, for sentinel node identification in younger women with unilateral low-risk PTC.

Methods

From January 2004 to January 2007, 90 female patients, ages 23 to 44 (mean = 35), with unilateral low-risk PTC (T_1-2N₀M₀) were prospectively studied. Mean tumor size was 1.3 cm (range, 0.8-3.7 cm). All patients underwent unilateral modified neck dissection. Prior to surgery, patients had, by random assignment, identification and biopsy of SLNs by methylene blue, alone (Group 1), or by sulfur colloid labeled with 99 m Technetium, gamma-probe guided surgery and methylene blue (Group 2).

Results

In the methylene blue group, SLNs were identified in 39 of 45 patients (86.7%). Of the 39 patients, 28 (71.8%) had positive cervical lymph nodes (pN+), and 21 patients (53.8%) had pSLN+. In 7 of the 28 pN+ patients (25%), metastases were also detected in non-SLN, thus giving a false-negative rate (FNR of 38.9% (7/18), a negative predictive value (NPV) of 61.1% (11/18), and an accuracy of 82.1% (32/39). In the combined technique group, the identification rate (IR) of SLN was 100% (45/45). Of the 45 patients, 27 (60.0%) had pN+, 24 (53.3%) had pSLN+. There was a FNR of 14.3% (3/21), a NPV of 85.7% (18/21), and an accuracy of 93.3% (42/45). The combined techniques group was significantly superior to the methylene blue group in IR (p = 0.035). There were no significant differences between two groups in sensitivity, specificity, NPV, or accuracy. Location of pN+ (55 patients) in 84 patients was: level I and V, no patients; level II, 1 patient (1.2%); level III, 6 patients (7.2%); level III and IV, 8 patients (9.5%); level IV, alone, 8 patients (9.5%); level VI, 32 patients (38.1%). In all 90 patients, IR of SLN was 93.3%, FNR, 25.6%, NPV, 74.4%, and accuracy rate, 88.1 percent.

Conclusions

Compared to a single technique, there was a significantly higher SLN identification rate for the combined technique in younger female with ipsilateral, low-risk PTC (T_1-2N₀M₀). Thus, a combined SLN biopsy technique seems to more accurately stage lymph nodes, with better identification of SLN located out of the central compartment. Regardless of the procedure used, the high FNR renders the current SLN techniques unsuitable for routine practice. Based on these results, prophylactic node dissection of level VI might be considered because 38.1% of our patients had such node metastases.

Systematic review and meta-analysis of sentinel node biopsy in thyroid cancer

Background

Sentinel node biopsy (SNB) is employed as standard treatment in some solid organ cancers to assess lymph node spread and enable targeted treatment. Several studies have investigated the role of SNB in thyroid cancer. This is a systematic review and meta-analysis of the role of SNB in the management of thyroid cancer.

Methods

A systematic search was performed in the PubMed database to identify all original articles on the role of SNB in thyroid cancer. Data on methodologies used, short-term outcomes and adverse effects were summarized, and used to address relevant clinical questions related to the application of the SNB technique in thyroid cancer.

Results

Twenty-four studies were included. The overall sentinel node (SN) detection rates for the blue dye, radioisotope and combined techniques were 83·7, 98·4 and 96 per cent respectively. A positive SN was seen in 42·9 per cent of patients with papillary thyroid cancer with an identified SN. The overall false-negative rates for the blue dye, radioisotope and combined techniques were 7·7, 16 and 0 per cent respectively. A negative frozen-section examination of the SN was unreliable in 12·0 per cent of patients. Immunohistochemical assessment of the SN showed evidence of nodal metastases in an additional 15 per cent of patients (7 of 47 sentinel nodes).

Conclusion

SNB in thyroid cancer is a promising technique that has the potential to avoid prophylactic lymph node surgery in up to 57 per cent of patients with clinically node-negative thyroid cancer.

Mutational and clinico-pathological analysis of papillary thyroid carcinoma in Serbia

Molecular pathogenesis of papillary thyroid carcinoma (PTC) is largely associated with mutational changes in the BRAF, RAS family and RET genes. Our aim was to assess clinico-pathological and prognostic correlations of these PTC-specific gene alterations, with a particular emphasis on the BRAF mutation, in a group of 266 Serbian PTC patients, for the first time. The reference center-based retrospective cohort included 201 (75.6%) females and 65 (24.4%) males aged 48.0±16.1 years (8-83 years old, range) diagnosed and treated for PTC during 1993-2008. Follow-up period was 53.1±41.6 months (7-187 months, range). BRAF and RAS mutations were determined by direct sequencing of genomic DNA. RET/PTC rearrangements were analyzed by RT-PCR/Southern blotting. Genetic alterations were detected in 150/266 tumors (56.4%). One tumor displayed two genetic alterations. The BRAF(V600E) was found in 84/266 (31.6%) cases, RAS mutations in 11/266 (4.1%) and RET/PTC in 55/266 (20.7%; 42/266 (15.8%) RET/PTC1 and 13/266 (4.9%) RET/PTC3). On multivariate analysis BRAF(V600E) was associated with the classical papillary morphology (P = 0.05), the higher pT category (P = 0.05) and advanced clinical stage (P = 0.03). In a proportional hazard model, BRAF(V600E) did not appear to be an independent risk factor for the faster recurrence (P = 0.784). We conclude that under the extensive thyroid surgery and limited application of radioiodine ablation BRAF(V600E) may not be an indicator of poorer disease-free survival during the short to middle follow-up period. However, it has a potential to contribute to patients stratification into high- and low-risk groups.

Sentinel node detection in patients with thyroid carcinoma: a meta-analysis

Objective

This study was designed to review the diagnostic performance of sentinel node (SN) detection for assessment of the nodal status in thyroid carcinoma patients and to determine the technique (using blue dye or Technetium-99m colloid (^99mTc)) that demonstrated the highest success rate with regard to the detection rate and sensitivity.

Methods

A comprehensive computer literature search of studies published in English language through December 2007 and regarding SN procedures in patients with thyroid disorders was performed in MEDLINE. Pooled values regarding the SN detection rate and the pooled sensitivity values of the SN procedure were presented with a 95% confidence interval (CI) for the different SN detection techniques.

Results

Ultimately, we identified 14 studies comprising a total of 457 patients. Of these, ten studies (n = 329 patients) used the blue dye technique with a pooled SN detection of 83% (95% CI, 79–87%). The remaining four studies (n = 128) used ^99mTc-colloid with a pooled SN detection of 96% (95% CI, 91–99%; p < 0.05 vs. blue dye technique).

Conclusion

In patients with suspected thyroid carcinoma, SN biopsy demonstrated a higher SN detection rate when ^99mTc was used (96%) instead of the blue dye technique (83%).

Sentinel lymph node biopsy as guidance for central neck dissection in patients with papillary thyroid carcinoma

BACKGROUND

Occult lymph node metastasis of papillary thyroid carcinoma (PTC) can be detected by sentinel lymph node (SLN) biopsy, but studies in larger patient cohorts undergoing complete central neck dissection may be required to assess the diagnostic accuracy of SLN. Therefore, the authors prospectively assessed the usefulness of SLN biopsy for the detection of central lymph node metastasis in patients with differentiated PTC who had no suspicious cervical lymphadenopathy.

METHODS

After peritumoral injection of methylene blue, SLN biopsy was performed in 50 patients with newly diagnosed PTC who had no palpable or ultrasound (US)-detected lymph node involvement. After SLN biopsy, all patients underwent total thyroidectomy and central neck dissection. The diagnostic accuracy of intraoperative SLN sampling was calculated by comparison with the final pathologic diagnosis.

RESULTS

SLNs were identified in 46 of 50 patients (92%); of these, 14 SLNs were positive and 32 SLNs were negative on intraoperative frozen sections. One patient had a positive SLN in the jugular region and subsequently underwent modified radical neck dissection. Final pathologic examination revealed that 18 patients (36%), including 4 who had negative SLNs, had central lymph node metastasis. Thus, the sensitivity, specificity, accuracy, and positive and negative predictive values of SLN biopsy were 77.8%, 100%, 92%, 100%, and 88.9%, respectively. Temporary and permanent hypocalcemia developed in 19 patients and 1 patient, respectively. There were no direct complications of SLN sampling.

CONCLUSIONS

SLN biopsy in patients with PTC without gross clinical or US lymph node involvement was able to detect occult metastasis with high accuracy and may have the potential to select patients who require central neck dissection.

Routine level VI lymph node dissection for papillary thyroid cancer: surgical technique

Total thyroidectomy is the treatment of choice for clinically significant papillary thyroid cancer (PTC); however, 10-15% develop palpable local recurrence in the cervical lymph nodes. Metastases in the cervical lymph nodes account for 75% of loco-regional recurrence and up to 50% of these patients eventually die of their disease. It is generally accepted that surgical excision of grossly involved lymph node disease should be carried out. The role of routine lymph node dissection, however, is greeted with far more controversy. Regional lymph node metastases have been shown to be associated with more frequent tumour recurrence. Not only is recurrence associated with increased disease-related mortality, but recent data have shown that the presence of involved lymph nodes is associated with adverse survival. Additionally, there have been significant changes to the way patients are managed after treatment for PTC in recent years. Surveillance previously relied on clinical assessment and radioiodine scans whereas now the use of serum thyroglobulin and high-resolution ultrasound are the standard as evidenced by recommendations by the American Thyroid Association. These techniques have greater sensitivity and subsequently lymph node metastases are being detected earlier and more frequently. This has led to a paradigm shift in the aims of treatment of PTC, from a focus on survival data to a focus on disease-free status. Routine central neck lymph node dissection can be carried out with no increased morbidity and can achieve lower 6-month stimulated thyroglobulin levels when compared with total thyroidectomy alone. Routine ipsilateral level VI lymph node dissection in addition to total thyroidectomy should be carried out for the management of clinically significant PTC.

Use of preoperative lymphoscintigraphy and intraoperative gamma-probe detection for identification of the sentinel lymph node in patients with papillary thyroid carcinoma

AIMS

Lymph node metastases for papillary thyroid carcinoma are associated with an increased incidence of locoregional recurrence. The use of preoperative lymphoscintigraphy and intraoperative gamma probe detection to localize the sentinel lymph node in papillary thyroid carcinoma was investigated.

METHODS

From February 2004 to December 2005 the sentinel lymph node technique was studied in 64 consecutive patients with cytological evidence of papillary thyroid carcinoma. The day before surgery, patients were submitted to US-guided peri-tumoural injection of the radiotracer and a lymphoscintigraphy was performed. In the operating room a total thyroidectomy was done, and thanks to a hand-held gamma probe the sentinel lymph node and all lymph nodes, belonging to the sentinel node compartment, were removed.

RESULTS

The gamma probe identified the sentinel lymph node in 62 patients (96.8%). We found 48 (77.5%) sentinel lymph node without metastases; 12 (19.3%) with metastases and 2 (3.2%) with micrometastases. In 7 cases (11.3%), with a negative sentinel lymph node, metastases in other nodes of the same region were recorded. In 22 cases (34.3%) the ultrasound give an erroneous indication (P=0.004). Five patients (8.0%), 4 with multifocal cancer, had a positive postoperative lymphoscintigraphy.

CONCLUSION

This study shows that the sentinel lymph node technique for papillary thyroid carcinoma is feasible, repeatable, and more accurate than preoperative ultrasound. In cases of multifocal thyroid lesions more patients should be enrolled to establish the utility of the radio-guided technique.