Elective neck dissection in papillary carcinoma of the thyroid

The Benefit of Primary Tumor Surgical Resection in Distant Metastatic Carcinomas of the Thyroid

OBJECTIVES/HYPOTHESIS

Thyroid cancer with distant metastasis (TCDM) at diagnosis has significantly worse survival rates when compared to localized/regional thyroid cancer. This study sought to report on the characteristics of patients presenting with TCDM and the potential survival advantage of surgical resection.

STUDY DESIGN

Data were acquired from the Surveillance, Epidemiology, and End Results (SEER) database with cases from 2004 to 2015.

METHODS

TCDM cases (n = 2,558) were identified from the SEER database. The Bonferroni correction was applied for multivariate analysis. Kaplan-Meier analysis was utilized to obtain disease-specific survival (DSS) rates. Cox regression analysis was utilized to identify independent factors significantly associated with survival.

RESULTS

The average age of diagnosis of TCDM was 62.0 (±17.5) years. Patients were predominantly white (74.6%), female (54.6%), in a relationship (56.0%), and between ages 36 and 80 years (76.4%). Cases consisted of papillary (57.2%), follicular (16.0%), medullary (8.9%), anaplastic (17.9%) TCDM histological variants. Overall 1-, 5-, and 10-year DSS rates were 72.0%, 56.8%, and 43.8%, respectively. Anaplastic and medullary variants had the worst 10-year DSS (0% and 25.5%, respectively). Patients who underwent surgical resection only and surgical resection with radiation were 49% and 59% less likely to die, respectively. Treatment, age, histology, T staging, relationship status, and metastasis site were determined to be significant predictors of survival.

CONCLUSIONS

Surgical resection with radiation was found to be a significant predictor of survival after applying the Bonferroni correction for all thyroid cancer variants except medullary. To increase survival, surgical intervention should be recommended in patients who are deemed to be medically tolerant of surgery.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1026-1034, 2021.

Routine prophylactic central neck dissection for low-risk papillary thyroid cancer is not cost-effective

BACKGROUND

The role of routine prophylactic central neck dissection (CND) in papillary thyroid cancer (PTC) remains controversial. The aim of this study was to evaluate the cost utility of the addition of routine CND in patients with low-risk PTC compared with total thyroidectomy (TT) alone.

METHODS

A Markov model for low-risk PTC was constructed with a treatment algorithm based on the American Thyroid Association guidelines for well-differentiated thyroid carcinoma. Utilities and outcome probabilities were derived from published medical literature. US 2010 costs were examined from a society perspective using Medicare reimbursement rates and opportunity loss based on published US government data. Monte Carlo simulation and sensitivity analysis were used to examine the uncertainty of probability, cost and utility estimates.

RESULTS

Initial TT alone is more cost-effective than TT with CND, resulting in a cost savings of US $5763 per patient with slightly higher effectiveness per patient (0·03 QALY) for a cost savings of $285 per QALY. Sensitivity analysis shows that TT alone offers no advantage when radioactive iodine (RAI) becomes more detrimental to a patient's state of health, when the incidence of non-neck recurrence increases above 5% in patients undergoing TT alone or decreases below 3·9% in patients undergoing TT with CND or when the rate of permanent hypocalcaemia rises above 4%.

CONCLUSIONS

TT with CND is not a cost-effective strategy in low-risk PTC. Initial TT alone is favourable because of the low complication rates and low recurrence rates associated with the initial surgery. Alternative strategies such as unilateral prophylactic neck dissection require additional study to assess their cost-effectiveness.

Radio-guided selective compartment neck dissection improves staging in papillary thyroid carcinoma: a prospective study on 345 patients with a 3-year follow-up

BACKGROUND

Prospective uncontrolled study to investigate in papillary thyroid carcinoma (PTC) patients: (1) Distribution of lymph node metastases within the neck compartments, (2) factors predicting lymph nodes metastases, and (3) disease recurrence after thyroidectomy associated with radio-guided selective compartment neck dissection (RSCND).

METHODS

We studied 345 consecutive PTC patients operated on between February 2004 and October 2011 at the S. Anna University Hospital, Ferrara (Italy). Patients with cervical lymph node metastases on preoperative ultrasonography and fine needle aspiration cytology were excluded. All patients underwent total thyroidectomy associated with SLN identification followed by RSCND in the SLN compartment, without SLN frozen section.

RESULTS

In patients with lymph node metastases, metastatic nodes were not in the central neck compartment in 22.6% of the cases. The presence of infiltrating or multifocal PTC was a predicting factor for lymph nodes metastases. The median follow-up was 35.5 months. RSCND was associated with a false-negative rate of 1.1%, a persistent disease rate of 0.6%, and a recurrent disease rate of 0.9%. The permanent dysphonia rate was 1.3%.

CONCLUSION

RSCND associated with total thyroidectomy may improve: (1) the locoregional lymph node staging, and (2) the identification of the site of lymphatic drainage within the neck compartments. Thus, considering the high false-negative rate of sentinel lymph node biopsy (SLNB), a radio-guided technique in PTC patients may guide the lymphadenectomy (ie, RSCND) to increase the metastatic yield and improve staging of the disease rather than avoid prophylactic lymphadenectomy (ie, SLNB).

Differentiated thyroid carcinoma of children and adolescents: 27-year experience in the yonsei university health system

Thyroid carcinomas are uncommon in childhood and adolescence. The aim of this study was to analyze clinical features and clinical outcomes of thyroid cancer in the pediatric population treated in the Yonsei University Health System. From September 1982 to June 2009, 90 patients (75 females, 15 males; female:male ratio of 5:1) with differentiated thyroid carcinoma were identified in our institute. The mean age at diagnosis was 15.8 yr old (range 4.8-19.9 yr). Cervical masses were most common clinical manifestations at diagnosis in 65 patients (72.2%). Forty-two patients underwent less than total thyroidectomy and 18 patients underwent total thyroidectomy. Thirty patients (33.3%) had lateral neck lymph node metastasis and seven patients (7.8%) had lung metastasis at the time of surgery. Among the 90 patients, recurrence occurred in 14 patients (15.5%). Mean follow-up period for patients with differentiated thyroid carcinoma was 81.6 months (13-324 months). No patients died of differentiated thyroid carcinoma. Patients with differentiated thyroid carcinoma who were < 20-yr-of-age were present with aggressive local disease and a high frequency of lymph node and distant metastasis. It is recommended that pediatric thyroid cancer should be managed mostly using proper surgical approach with thyroidectomy and lymph node dissection when indicated.

Predictive factors for lateral occult lymph node metastasis in papillary thyroid carcinoma

Management of lateral no necks in papillary thyroid carcinoma (PTC) is very controversial. The aim of this study was to find predictive factors of lateral neck involvement in N0 PTC to help the clinician in his decision to treat the lateral compartment. We retrospectively analysed 173 patients who underwent thyroidectomy and lateral prophylactic neck dissection for PTC >10 mm. Predictive factors for occult lateral lymph node metastasis including sex, age, tumour size, multifocality and bilaterality, tumour extracapsular spread, vascular invasion and presence of a tumour capsule were examined by multivariate analysis. There were three independent predictive factors for occult lateral lymph node metastases in multivariate analysis: tumour extracapsular spread (p < 0.0001), vascular invasion (p < 0.001) and age <45 years (p < 0.027). When none of these factors was present, the risk of occult metastases was <5 %. The risk increased up to 56 % when at least two of these factors were present. These findings suggest that, in patients older than 45 years with neither tumour extracapsular spread nor vascular invasion on histopathological examination, occult lymph node metastases are very uncommon. In that case further discussion regarding the risks and benefits of lateral nodal dissection may be warranted.

Occult Lymph Node Metastases Increase Locoregional Recurrence in Differentiated Thyroid Carcinoma

Objectives:

The impact of occult lymph node metastasis (OLNM) on locoregional recurrence (LRR) and survival in patients with N0 differentiated thyroid carcinoma is unclear, because no large study has been carried out. A retrospective study was conducted in our department to assess the influence of OLNM.

Methods:

We included 201 patients treated by prophylactic neck dissection for N0 differentiated thyroid carcinoma between 1974 and 2006. The incidence of OLNM and predictive factors for recurrence and survival were assessed.

Results:

The incidence of OLNM was 20%. Necks were involved at levels VI, III, II, IV, V, and I, in decreasing order of frequency. After a mean follow-up of 9 years, the rate of LRR was 8.9% and the rate of distant metastasis was 3.4%. An age of greater than 55 years and the presence of OLNM were predictive factors for LRR. An age of greater than 55 years and the presence of LRR were predictive factors for distant metastasis. The presence of distant metastasis was the only factor that significantly and independently influenced the disease-specific survival.

Conclusions:

We found that OLNM occurred in only 20% of N0 patients. The presence and especially the number of OLNMs on neck dissection were major risk factors for LRR in this study, but did not affect the disease-specific survival.

Analysis of prognostic factors in patients with multiple recurrences of papillary thyroid carcinoma

PURPOSE

Numerous studies in the past have mentioned various factors that influence the recurrence of papillary thyroid carcinoma, including age, tumor size, advanced stage, extrathyroidal extension, and distant metastasis, and attempts have been made to classify the disease into low-risk and high-risk group based on these clinicopathological factors. However, there has been relatively scarce study on patients with multiple recurrent papillary thyroid carcinoma. This study analyzed the risk factors associated with such cases.

MATERIALS AND METHODS

This study investigated various clinicopathological factors of 416 patients who were diagnosed with papillary thyroid carcinoma and received primary surgery at Yonsei University Wonju College of Medicine, Department of Surgery, from January 1983 to December 2006 and were followed up until October 2010. An investigation of factors associated with patients showing multiple recurrences was made.

RESULTS

Patients were divided into 3 groups: group 1 (no recurrence, n=380), group 2 (1 recurrence only, n=21), and group 3 (multiple recurrences, n=15). The univariate analysis on risk factors revealed tumor size greater than 2 cm, multifocality, clinical apparent lymph node metastasis to be risk factors associated with multiple recurrences of papillary thyroid carcinoma. A multivariate analysis performed on variables selected from univariate analysis demonstrated no significant risk factor. The 10-year disease-specific survival for 3 different patient groups (group 1, 2, and 3) was 100%, 100%, and 83.1%, respectively, and patients in more clinically advanced group demonstrated poorer prognosis (p<0.001). The 10-year overall survival rate for the 3 patient groups was 93.9%, 100%, and 92%, respectively, and clinically advanced groups tended to show poorer overall survival rate as well (p=0.046).

DISCUSSION

A more aggressive and extensive surgery, as well as closer follow up, is to be required when operating on patients with tumor size greater than 2 cm, multifocality, clinical apparent lymph node metastasis. The use of imaging modalities, such as ultrasonography and PET-CT scan, may be desirable when monitoring such patients.

Multi-targeted approach in the treatment of thyroid cancer

While accounting for only 1% of solid organ malignancies (9% in women), thyroid carcinoma is the most common malignancy of the endocrine system. Although most patients have a favorable prognosis, over 1,500 people will die from thyroid carcinoma each year. The spectrum of disease types range from papillary thyroid cancer, which is a well-differentiated indolent tumor, to anaplastic carcinoma, a poorly differentiated fulminant cancer. With advances in diagnostic methods, surgical techniques, and clinical care of patients with thyroid carcinoma, the current management of thyroid cancer demands a multidisciplinary approach. The majority of patients with well-differentiated thyroid carcinoma of follicular cell origin are cured with adequate surgical management; however, some thyroid malignancies such as medullary thyroid carcinoma (MTC) or poorly differentiated thyroid carcinomas frequently metastasize, precluding patients from a curative resection. As such, novel palliative and therapeutic strategies are needed for this patient population. Here, we explore the current management of thyroid carcinoma, including surgical management of the primary tumor, lymph node disease, and locoregional recurrence. Likewise, we explore the application of current molecular techniques, reviewing nearly two decades of data that have begun to elucidate critical genetic pathways and therapeutic drug targets which may be important in specific thyroid tumor types.

Thyroid cancer and lymph node metastases

There is considerable controversy about the prognostic implications of lymph node metastases in patients with papillary thyroid cancer and whether patients with papillary thyroid cancer should have a prophylactic or selective central (level VI) neck dissection. Some experts report that a prophylactic ipsilateral neck dissection results in fewer patients having elevated thyroglobulin levels but others do not agree. A comprehensive review of the literature suggests that the presence of macroscopic metastases of papillary thyroid cancer in cervical lymph nodes results in a higher recurrence rate and increased death rate, especially in patients 45 years of age or older, whereas microscopic nodal metastases do not appear to adversely influence survival. Until more information is available we recommend preoperative ultrasonography and a selective ipsilateral neck dissection for patients with papillary thyroid cancer.

Pattern of lateral neck metastases in N0 papillary thyroid carcinoma

Background

Indication and extent of lateral prophylactic neck dissection (PLND) in papillary thyroid carcinoma (PTC) is very controversial.

Methods

We retrospectively analysed 131 patients who underwent thyroidectomy and prophylactic lateral neck dissection from level II to V for PTC.

Results

140 PLND were performed. The occult lymph node metastases (OLNM) overall rate was 18.6%. The incidence of node involvement was 10% at level III and 6.4% at level IIa. Level IV and level Vb were both concerned by 5.7% OLNM. Only 2.9% of level IIb contained OLNM. None of the level Va ND revealed OLNM.

Conclusions

OLNM from PTC occurs commonly in level IIa, III, IV and Vb. Incidence in other levels is low. For surgeons that usually perform PLND, we believe that a selective neck dissection of levels IIa, III, IV and Vb in N0 neck PTC is sufficient for the clearance of occult metastases.

Adequate surgery for papillary thyroid cancer

Papillary thyroid cancer (PTC) is the most common type of thyroid cancer, occurring in about 80% of cases. Treatment consists ofsurgery, selective adjuvant radioiodine ablation, thyroid stimulating hormone suppression and surveillance. The extent of thyroidectomy and the extent of lymphadenectomy are controversial. Total or near-total thyroidectomy is recommended for the treatment of PTC, except those with papillary microcarcinoma (PTC < 1 cm) found incidentally after a thyroid lobectomy. This allows for treatment of possible multifocality (up to 8o% of cases), facilitates the use of radioiodine for remnant ablation and increases the sensitivity of thyroglobulin levels for surveillance, with complication rates comparable to lobectomy when done by experienced endocrine surgeons. A recent large database study supports this recommendation for PTCs > or = 1 cm; the optimal treatment of PTCs < 1 cm is still debatable, though many surgeons will perform total or near-total thyroidectomy for the reasons listed above. Contemporary series report lymph node metastases in up to 64% of patients, though their clinical significance is unclear. Reports are conflicting with respect to the impact of cervical nodal metastases on recurrence rates and survival, which are also affected by other patient, tumour and treatment-related factors. Therapeutic lymph node dissection is indicated for biopsy-proven nodal metastases. Prophylactic lateral neck lymphadenectomy is not recommended by experts in Europe and the USA. Prophylactic central neck lymphadenectomy is controversial, and may be advocated in selected patients while balancing the risks of the procedure.

Management of regional metastases in well-differentiated thyroid cancer

Thyroid cancer represents the most common endocrine cancer, and rates have been increasing over the last 3 decades. The treatment of cervical metastases in well differentiated thyroid cancer remains in evolution. Many questions require further resolution. Unlike many other malignancies, most large studies have found that overall survival is not significantly affected by regional metastases. On the other hand, several studies have noted that regional disease may decrease survival in selected patient groups. The greatest effect of lymph node metastases seems to be an increase in recurrence rates. Except for the compartment-oriented removal of clinically positive nodes, few strong recommendations may be made.

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.

Workup of well-differentiated thyroid carcinoma

BACKGROUND

Well-differentiated thyroid carcinoma (WDTC) includes three main entities: papillary thyroid carcinoma (PTC), follicular thyroid carcinoma (FTC), and Hurthle cell carcinoma (HCC). A thorough knowledge of the natural history and presentation of these carcinomas is vital to the thyroid surgeon.

METHODS

This review details the preoperative workup of patients having or suspected to have WDTC. We review the history, physical examination, laboratory, and radiographic evaluations that optimally prepare the surgeon to determine the ideal surgical thyroid and neck treatment for patients with WDTC.

RESULTS

A fiberoptic evaluation of the larynx is integral to the physical examination, and a laryngeal assessment is performed for all patients who will undergo thyroid surgery. It must be noted that vocal cord paralysis can be subtle and does not always present with clear dysphagia or voice change. Ultrasound and FNA are the primary tools of preoperative assessment. Given that patients with preoperative FNA positive for papillary cancer are expected to have clinically significant nodal disease in one third of cases, radiographic evaluation must be appropriately aggressive. The combination of US and CT allows assessment of the central and lateral neck nodes and the thyroid's relationship to central neck viscera.

CONCLUSIONS

The overriding principle in the surgical treatment of WDTC is that the surgeon recognizes and encompasses all gross disease in the thyroid and neck nodes at first surgery. The extent of thyroidectomy is tailored not only to the patient's risk group and gross operative findings but also to the progress of the specific surgery in terms of parathyroid and recurrent laryngeal nerve preservation.

The implication of lymph node metastasis on survival in patients with well-differentiated thyroid cancer

Though survival for well-differentiated thyroid cancer is very good, specific populations suffer greater recurrence and mortality. Defining these cohorts can significantly influence prognosis and extent of treatment. This study, using a large, multi-institutional database, seeks to determine how the presence of lymph node disease in patients with well-differentiated thyroid cancer affects outcome. The Surveillance, Epidemiology, and End Results (SEER) database is a large-scale sample of 14 per cent of the U.S. population. It was used to identify patients with papillary and follicular thyroid carcinomas and identify the prognostic implications of lymph node metastasis. Additional factors, including presence of metastasis, age, and tumor size, were compared using multivariate and chi2 analyses. Of 19,918 patients identified, lymph node status was known for 9,904 (49.7%). On multivariate analysis, age > 45 years, presence of distant metastasis, large tumor size, and lymph node involvement significantly predicted poor outcome. Overall survival at 14 years was 82 per cent for node negative and 79 per cent for node positive patients (P < 0.05). This study shows that the survival of patients with well-differentiated thyroid cancer is adversely affected by lymph node metastases. The optimum treatment for this cohort needs further delineation, as particular populations are at greater risk of recurrence and death.

Detection and surgical treatment of cervical lymph nodes in differentiated thyroid cancer

There is considerable controversy regarding the treatment of patients with cervical metastases from differentiated thyroid cancer. Most have papillary carcinoma and the main areas of contention relate to methods of assessment and staging, surgical management and mode of follow up. there is little evidence to support elective anatomical imaging with CT or MRI in those patients with suspected or proven malignancy at the primary site as indicated by fine needle aspiration cytology (FNAC) but who have no clinical evidence of nodal disease. The role of routine ultrasound (US) in the pre-operative assessment of suspected or known malignancy is developing but is largely unproven. When it is performed, high risk areas for metastatic neck disease (levels II-V) should be assessed. Suspicious nodes on US should be further evaluated by FNAC. Suspected or proven neck disease may be further assessed pre-operatively with CT or MRI and then treated surgically. Disease in the central compartment requires a total thyroidectomy and level VI central compartment neck dissection. Suspected or proven lateral compartment cancer should be treated by selective neck dissection (at least levels III, IV, and V) below the accessory nerve. There is no role for 'Berry picking' and clinically node negative high risk patients should have an elective central compartment level VI neck dissection. Sentinel node biopsy lays no role and neither does elective lateral compartment surgery in patients with no clinical or radiological evidence of disease. For follow up, US represents the most sensitive means of detecting neck recurrences and in the presence of an elevated serum thyroglobulin, imaging may also include whole body iodine-131 scanning and anatomical imaging with CT or MRI. The role of PET remains controversial but is likely to develop further as the technique becomes more widely available. In the future, the concentration of patients with this disease in large center can only improve the way we treat differentiated thyroid cancer.

Radioactive iodine offers survival improvement in patients with follicular carcinoma of the thyroid

BACKGROUND

The use of radioactive iodine (RAI) in patients with follicular thyroid carcinoma is well established. How its use affects patient outcome and which patients benefit is understood poorly. This study seeks to determine how RAI influences survival and to delineate the populations that are impacted most.

METHODS

The Surveillance, Epidemiology, and End Results database is a sample of approximately 14% of the US population. It was used to identify patients with follicular thyroid carcinomas and the treatment that they received. Factors such as the presence of lymph node and distant metastases, age, and tumor size were included for analysis.

RESULTS

A total of 4317 patients were identified with follicular thyroid carcinoma. Of these, the records of 2112 patients who were entered in the study after 1988 contained the required data and were included for analysis. Median follow-up time was 95 months. Factors that were associated with increased risk of death included distant metastatic disease, cervical lymph node disease, and the lack of RAI use. Protective factors were tumor size of <2 cm and age of <45 years. Some patients with a greater number of risk factors benefited from RAI.

CONCLUSION

RAI provides survival benefit to some patients with follicular carcinoma of the thyroid. The greatest improvements were seen in those patients with locoregional or distant disease spread.

Preventable reoperations for persistent and recurrent papillary thyroid carcinoma

BACKGROUND

Cervical recurrence occurs in up to 25% of patients with papillary thyroid carcinoma (PTC) due either to the aggressive biology of PTC or to inadequate treatment. This retrospective study was designed to determine the frequency of inadequate surgical or medical therapy as a cause of persistent or recurrent PTC.

METHODS

We identified all patients who underwent reoperation for persistent (within 6 months of initial or pre-referral operation) or recurrent (greater than 6 months after initial or pre-referral operation) PTC from 1992 to 2003. Medical records including initial preoperative imaging, operative, and histopathology reports were reviewed. The initial surgical procedure was considered incomplete if all gross neoplasm was not removed or if "node plucking" was performed, and a subsequent recurrence occurred in the same cervical compartment.

RESULTS

Seventy-two consecutive patients underwent reoperation for persistent (17) or recurrent (55) PTC. Of the 17 patients with persistent PTC, reoperation was judged to have been possibly preventable in 14 (82%) due to inadequate preoperative imaging or incomplete initial surgery. Of the 55 patients with recurrent PTC, reoperation was judged to have been possibly preventable due to incomplete initial surgery in 14 (25%). Based on the National Comprehensive Cancer Network guidelines, 33 (46%) of 72 patients with persistent or recurrent PTC received inadequate initial local treatment.

CONCLUSIONS

Reoperation in 28 (39%) of 72 patients with persistent or recurrent PTC was potentially preventable. Accurate preoperative staging and adherence to the suggested National Comprehensive Cancer Network treatment guidelines may minimize the need for cervical reoperation.

Value of the Cervical Compartments in the Surgical Treatment of Papillary Thyroid Carcinoma

In the treatment of papillary thyroid carcinoma (PTC), supplementary lymph node dissection (LND) is not well standardized. The purpose of this study was to evaluate the significance of the cervical compartments in the lymphatic spread of PTC and the impact of modified radical neck dissection (MRND) as an additional surgical procedure to thyroid resection. From 1999 to 2002, LND of the central compartment (compartment A) was performed in 39 patients. Among this group, additional MRND of the ipsilateral compartment (compartment B) and the contralateral compartment (compartment C) was performed in 29 and 15 patients respectively, who met the selection criteria. The mean number of nodes resected was 11 (5-22) in compartment A, 23 (8-37) in compartment B, and 22 (10-31) in compartment C. Histopathologic findings revealed node invasion of compartment A in 25 patients (64.1%), of A and B in 20 patients (51,2%) and of A, B, and C in 13 patients (33.3%). From the 25 patients with metastases in compartment A, 80% (20 patients) already had metastases in compartment B and 52% (13 patients) had metastases in all three compartments. All patients free of metastasis (M0) in compartment A were also metastasis free in both lateral compartments. Postoperative whole-body scanning I(131) in M0 patients showed no uptake at all. Mapping of the cervical anatomy in compartments seems to be a useful taxonomy for clarifying the lymphatic spread of PTC. Patients having PTC without metastasis in compartment A are almost certainly disease free at the time of operation. Lymph node metastasis in the central compartment appears to be a valuable indicator of lymphatic invasion of the lateral compartment and a strong indication for performance of a unilateral or bilateral MRND to complete the surgical removal of tumor.

Lymph node surgery in papillary thyroid carcinoma

BACKGROUND

The impact of nodal disease remains controversial in papillary thyroid carcinoma (PTC).

STUDY DESIGN

One surgeon treated 159 unselected patients, who were followed up for 1 to 27 years. We present a retrospective analysis with respect to nodal disease. Occult nodal disease was investigated, including metachronous nodal disease (mpN(1)) in primarily node negative patients (pN(0), clinical [c]N(0)).

RESULTS

Therapeutic lymphadenectomies, prophylactic lymphadenectomies, or no lymphadenectomy were carried out in 42 (cN(1)), 29 (cN(0)), and 88 (cN(0)) patients, respectively, with stage pN(1) in 41 (98%), in 5 (17%), and in 2 (2.3%) patients, respectively (17% versus 2.3% p < 0.005). Sensitivity and specificity of clinical staging were 85% and 99%, respectively. More frequent prophylactic lymphadenectomy during the study period (p = 0.002) led to a nonsignificant increase in stage pN(1) (26% versus 30%). Immunohistochemistry led to upstaging of only 3% of histologically negative nodes and one (4%) pN(0) patient. Nodal recurrence occurred in 8 of 156 patients (5%) treated for cure, in 12% of pN(1) versus 3% of pN(0) cN(0) tumors (p = 0.009), in 15% of TNM high-versus 3% of low-risk patients (p = 0.006), and in 5% each of patients, younger than 45 and 45 years or more. In TNM high-risk patients, tumor-related survival was 50% for stage pN(1) versus 86% for stage pN(0), cN(0) (p = 0.03) (100% and 100% in low-risk patients).

CONCLUSIONS

The rate of occult nodal disease might be relatively low, and it does not frequently progress to clinical recurrent disease. Clinical nodal status might be valid for deciding the extent and radicality of node dissection. Prophylactic (central) lymphadenectomy should be carried out without radicality-associated morbidity. Macroscopic nodal disease warrants more rigorous, compartment-oriented lymphadenectomy. There is no rationale for detection of occult disease and micrometastasis by frozen section or immunohistochemistry.

Intraoperative lymphatic mapping and sentinel lymph node biopsy in patients with papillary carcinoma of the thyroid gland

We examined the feasibility of sentinel lymph node biopsy for thyroid cancer. Thirty-eight patients with papillary thyroid carcinoma underwent intraoperative lymphatic mapping and sentinel lymph node biopsy. At surgery, we exposed the thyroid gland and used a tuberculin syringe to inject 0.2 ml of 1% patent blue dye directly into the thyroid mass. The lymphatics and the lymph node dyed with blue dyes, was excised as a sentinel lymph node. Modified radical neck dissection was performed following sentinel lymph node biopsy and the diagnostic ability of sentinel lymph node biopsy was examined. A sentinel lymph node was identified successfully in 27 (71%) of 38 patients. Sentinel lymph node biopsy removed one to three lymph nodes (median, two nodes). Eighteen patients had paratracheal sentinel lymph nodes, five patients had jugular sentinel lymph nodes, and four patients had both. Histological nodal metastasis was recognized in 16 of 27 cases. The positive rate of cancer metastases in sentinel lymph nodes was 58%, which was significantly higher than 11% in non-sentinel lymph nodes. Diagnostic ability of sentinel lymph node biopsy showed that accuracy was 89%, sensitivity was 84%, and specificity was 100%. Our preliminary study indicated that sentinel lymph node biopsy was available on detection of non-palpable nodal metastasis in the patients with thyroid cancer; however, further experience and refinement are needed.

Initial treatment of differentiated thyroid carcinoma

Many large, retrospective studies have been performed and form the basis for how we define risk groups of patients with differentiated thyroid carcinoma and how the three basic therapeutic modalities (surgery, radioiodine and levothyroxine) affect two primary outcomes disease recurrence and death. In this review, we have hopefully distilled much of that information into a proposed current therapeutic approach to individual patients with differentiated thyroid cancer.

Do the level of nodal disease according to the TNM classification and the number of involved cervical nodes reflect prognosis in patients with differentiated carcinoma of the thyroid gland?

BACKGROUND AND OBJECTIVES

The importance of nodal involvement as a prognostic factor in differentiated carcinoma of the thyroid gland remains controversial. We therefore attempted to confirm the prognostic factors in differentiated thyroid carcinoma, with special reference to nodal status.

PATIENTS AND METHODS

A total of 139 patients with differentiated thyroid cancer followed for 2-27 years, with a median follow-up of 7 years were studied. All patients underwent surgical resection, either subtotal, total, or lobectomy, with modified radical neck dissection. Survival was calculated using the Kaplan-Meier method.

RESULTS

Ten (7%) patients have died from thyroid cancer. Adverse prognostic factors included age >45 years (P=0.0120), the presence of distant metastases (P=0.0006), and TNM stage (P=0.0002). The number of lymph nodes dissected ranged from 6 to 92, with an average of 26. Lymph node metastases were found in 102 (73%) patients. There was no difference in survival according to the level of nodal disease by the TNM classification. Furthermore, the number of cervical lymph nodes involved had no effect on the survival.

CONCLUSION

Our results suggest that the presence of histologically confirmed lymph node metastases is not an important prognostic factor in patients with differentiated thyroid carcinoma.

Therapeutic strategies and long-term results in differentiated thyroid cancer

Differentiated thyroid carcinoma (DTC) is usually an indolent tumor associated with a low mortality. However, DTC, particularly papillary thyroid carcinoma, happens to be a multicentric tumor and tends to spread to the regional lymph nodes in the early stage of the disease; some patients with DTC do die from metastatic or recurrent disease. Despite the small number of these patients, therapeutic strategies designed to prevent such outcomes should be pursued. In this review, we attempt to evaluate the impact of different therapeutic strategies on survival and recurrence. Consequently, we conclude that the surgical approach to DIC should be individualized on the basis of the biologic behavior of the tumor, rather than on the extent of cancer involvement in the thyroid and regional lymph nodes. It is mandatory to expand our efforts to identify high-risk patients more accurately, thereby facilitating more rational approaches to treatment.

Modified neck dissection in the treatment of differentiated thyroid carcinoma

The prognosis of differentiated carcinoma of the thyroid has been reported to be extremely favourable. Previous studies have concluded that lymph node metastasis do not affect survival rates in patients with differentiated thyroid carcinoma. Therefore, nodal metastasis has not been evaluated as a prognostic factor in recent definitions of risk groups. To determine the significance of nodal disease, we reviewed 219 consecutive patients with differentiated thyroid cancer (191 papillary, 14 follicular and 14 Hurtle cell carcinomas). Fifty-five patients were treated with modified neck dissection and all of them received adjuvant radioiodine. There were recurrences in 25 patients (11.4%), with follow-up ranging from 6 months to 14 years. Systemic disease occurred synchronously in two patients, and four patients died of thyroid carcinoma.

Impact of lymph node metastasis in differentiated carcinoma of the thyroid: a matched-pair analysis

BACKGROUND

Cervical lymph node metastasis in differentiated thyroid carcinoma has mostly been found to have little relationship to prognosis. However, some studies report nodal involvement to be an adverse factor, while others have found it to be favorable. We have undertaken a matched-pair analysis of previously untreated patients, with and without ipsilateral neck metastasis, to examine the significance of nodal spread in patients with otherwise equivalent prognostic factors for differentiated thyroid cancer.

METHOD

From a database of 931 patients, treated from 1930 to 1980, we used a computer to match patients with confirmed lateral neck metastasis (N1) to those who were stage NO, and had the following identical prognostic factors: no distant metastasis, age (within 4 years), and tumor size, histology, and intrathyroidal extent. When possible, matches were also made for gender, multifocality, and extent of thyroid surgery. Survival and treatment failures were analyzed, with and without stratification for age.

RESULTS

We were able to select 100 N1 patients with corresponding NO patients, sharing the major prognostic risk factors as listed. Overall, there was no difference in survival, although N1 patients more often had recurrence. Mortality increased with age. Analysis at high-risk age (45 years and older) showed significantly more recurrences in N1 patients (p = .008). Twenty-year survival in N1 patients over the age of 45 was lower than that of NO patients. On the other hand, under the age of 45, N1 patients had better survival. These differences, however, did not reach statistical significance.

CONCLUSION

Nodal involvement in older patients with thyroid cancer increases the risk of recurrence, although no significant difference in survival is observed in relation to age.

Therapeutic implications of prognostic factors in differentiated carcinoma of the thyroid gland

Differentiated thyroid carcinoma is a relatively indolent disease. Despite the usually favorable prognosis, differentiated thyroid cancer is fatal in some patients. In the past, treatment strategies were often based upon incomplete knowledge or inaccurate assumptions regarding the significance of the presenting characteristics of the tumor and patient. More recently, several large retrospective reviews have analyzed various presenting factors and have identified those that have prognostic significance and those that do not. Significant prognostic factors are age, primary tumor size, histology, grade, local tumor extension, and M stage. N stage appears to be a significant factor in older patients but not in younger patients. Gender, focality, and a history of prior irradiation are not significant prognostic factors. Using this knowledge, patients can be grouped into low, intermediate, and high risk groups. Prognostic factor and risk group analysis has facilitated the development of more rational treatment algorithms. Low risk patients can usually be treated with lobectomy and suppression therapy. For high risk patients, total thyroidectomy and adjuvant radioiodine is advocated. Treatment for patients in the intermediate risk group should be individualized. Prognostic factor and risk group analysis makes a selective approach to differentiated thyroid cancer possible. Such an approach can spare many patients the morbidity and expense of unnecessarily aggressive treatment without compromising outcome.

Classification of papillary cancer of the thyroid based on prognosis

Between 1965 and 1988 there were 2953 patients with papillary carcinoma treated at Noguchi Thyroid Clinic. Among them 761 patients were excluded because the primary tumor was < 10 mm in maximum diameter, the patient's age was > 80, or the patient underwent noncurative surgery. The remaining 2192 patients, 192 men and 2000 women, were analyzed. The mean follow-up period was 12.5 years. Total thyroidectomy, subtotal thyroidectomy, lobectomy with or without isthmectomy, and less than lobectomy were performed in 2.3%, 40.3%, 44.2%, and 13.2%, respectively. Modified radical neck dissection, partial node excision, and no node excision were performed in 77.8%, 6.4%, and 15.8%, respectively. Men and women were separately analyzed because their risk factors and prognosis were significantly different. Multivariate analysis was carried out according to Cox's regression hazard model. Independently significant factors affecting prognosis in men were aged and gross nodal metastasis; and age, gross nodal metastasis, tumor size, and number of adhered tissues or organs were the factors in women. Based on those risk factors patients were classified into three groups. For men, 65.6% were classified in the excellent group and their 10-year survival was 98.4%; 17.2% were classified as intermediate and 17.2% as poor with survival rates of 90.1% and 74.4%, respectively. For female patients 69.6% were classified in the excellent group, 18.6% in the intermediate group, and 11.9% in the poor group with 10-year survivals of 99.3%, 96.4%, and 88.8%, respectively.

Risk of bilateral cervical lymph node metastases in papillary thyroid cancer

We evaluated the risk of bilateral or contralateral cervical lymph node metastases in 135 patients with papillary thyroid cancer who underwent bilateral neck dissection. We confirmed that bilateral jugular lymph node metastases were frequent in patients with obvious carcinoma in both lobes of the gland, in those with cancers arising in the isthmus, in those with clinically detectable bilateral lymphadenopathy, and in those with recurrent thyroid cancer. However, only 24% of the patients who had cancer clinically confined to one lobe with no bilateral or contralateral lymphadenopathy had histologically detected bilateral or contralateral jugular lymph node metastases. But the occurrence of contralateral jugular lymph node metastases was significantly correlated with both clinical lymphadenopathy in the ipsilateral neck and contralateral paratracheal lymph node metastases. Bilateral lymph dissection might be beneficial for these patients.

Prognostic significance of cervical lymph node metastases in differentiated thyroid cancer

During the last decade, several analyses of prognostic factors for differentiated thyroid cancer (DTC) have been reported. Although these studies have established a framework for rational treatment planning, they have not fully answered questions regarding the prognostic significance of cervical lymph node metastases. An analysis of patients treated for DTC at our institution over a 34-year period has shown several factors to be significant by log-rank analysis, including the presence of cervical lymph node metastases, age greater than or equal to 50 years, a primary cancer size of greater than 3.0 cm, and distant metastases. Further analysis has shown the node-negative and node-positive patient groups to be similar in regard to age, size of primary cancer, and the presence of distant metastases. This report compares our data with those of other studies that have investigated the association of cervical lymph node metastases and a poorer prognosis in patients with DTC. When considered as a group, these studies support the finding of the prognostic significance of cervical lymph node metastases, particularly that of palpable lymphadenopathy in older patients.

Prognostic factors and management considerations in patients with cervical metastases of thyroid cancer

Included among the controversies involving thyroid cancer are the risk factors and treatment decisions in patients with nodal metastases. We have reviewed selected clinical, pathologic, and therapeutic parameters in patients who present with cervical node metastases and related these parameters to disease outcome. There were 108 patients (68 women, 40 men), who had a mean age of 54 years. Univariate analysis showed a significantly increased risk of recurrence to be associated with the presence of primary tumor invasion (vascular, lymphatic, nerve, or muscle), the age and sex of the patient, the presence of mediastinal nodes, and adjuvant treatment with iodine 131. The presence of tumor invasion, the age and sex of the patient, and the presence of mediastinal nodes were significantly associated with higher rates of recurrence when tested by multivariate analysis. The 5- and 10-year disease-free survival rates were 76% and 72%, respectively, with a mean follow-up of 86 months. A comparison of recurrence and survival rates in thyroid cancer patients who were either node positive or node negative during the same 10-year period (152 patients) showed no statistically significant differences. However, node-positive patients with the risk factors of tumor invasion, age over 45 years, and positive mediastinal nodes had more aggressive disease. Although thyroid cancer patients with nodal metastases generally have a good prognosis, high-risk subgroups have been identified who may benefit from a more aggressive therapeutic and follow-up approach.

Papillary thyroid cancer and its surgical management

The surgical management in papillary thyroid cancer has been highly controversial. In the Department of Surgery (II), Kanazawa University Hospital, the surgical management especially for cervical lymph node metastases has changed since 1973 from a conservative approach to an aggressive one. In order to determine whether an aggressive approach is warranted, a retrospective multivariate analysis was carried out on 106 cases of papillary thyroid cancer. The patients have been followed for 10-28 years. Multivariate analysis was conducted following Cox's model. By this analysis, aggressive management appeared to have no impact on survival or relapse-free survival. However, age, sex, tumor size, and cervical lymphadenopathy were confirmed to be important prognostic factors in survival and/or relapse-free survival.

Prospective management of nodal metastases in differentiated thyroid cancer

Previous studies have concluded that lymph node metastases do not affect survival rates in patients with differentiated thyroid carcinoma and, therefore, nodal metastasis has not been evaluated as a prognostic factor in recent definitions of risk groups. To determine the significance of nodal disease, we reviewed 227 consecutive patients with differentiated thyroid carcinoma (173 with papillary, 37 with follicular, and 17 with Hürthle cell carcinoma). Of 70 (31%) patients with lymph node metastases (14 [20%] palpable preoperatively and 56 [80%] detected by routine sampling of middle and lower cervical nodes), 13 (19%) developed a recurrence compared with only 3 of 157 (2%) without nodal disease (p less than 0.01). Sixty-eight patients were treated with modified neck dissection, 63 of whom received adjuvant radioiodine. There were 10 recurrences in 63 patients (16%) who had been treated with radioiodine, compared with 3 recurrences in 7 (42%) patients who did not receive adjuvant radioiodine. Follow-up ranged from 2 to 28 years, with a mean of 8 years. Involvement of the lymph nodes was a marker for systemic disease occurring synchronously in 4 of 5 patients who presented with distant metastases and preceding systemic recurrence in 9 of 10 patients. Four patients (2%), all with lymph node metastases (three with concomitant extrathyroidal invasion and one with systemic metastases at initial presentation), died of thyroid carcinoma. Cervical lymph node metastases were associated with a higher incidence of recurrence and occurred synchronously or preceded the development of distant metastases in 13 of 15 (87%) patients. Although these findings were not statistically significant for overall survival, they lend support to routine cervical lymph node sampling for detection of and modified neck dissection with adjuvant radioiodine therapy for treatment of lymph node metastases. Such measures should reduce the subsequent recurrence rate and permit early detection and treatment of systemic disease.

Neck dissection for thyroid cancer

Decisions concerning the extent of surgical treatment for thyroid cancer remain controversial. Limited surgical procedures, designed to remove only the cancer that is clinically evident, can be successful since the primary determinants in survival are age, sex, and histologic type rather than number of positive nodes or other factors. A retrospective review of 339 patients who had surgical procedures for cancer of the thyroid at MDA hospital from 1975 to mid-1989 did not show a conclusive advantage for any type of neck dissection. The operations were tailor-made to include all evident clinical cancer. Secondary procedures, such as surgery, radioactive iodine, radiation therapy were successful in treating recurrences, which occurred in all surgical groups, whether limited or radical.

Modified radical neck dissection in cancer of the mouth, pharynx, and larynx

A retrospective analysis of 390 determinate radical neck dissections (RND) performed for cancers of the mouth, pharynx, and larynx was carried out. There were 75 patients (19%) who had a modified RND. These were separately analyzed and the outcome was compared to those who had a standard total RND. Our goal was to assess the effectiveness of modified RND in controlling disease in the neck, and to identify its impact on survival and quality of life. Overall neck recurrence rate in the entire modified RND group was 28%, 35% in the partial RND, and 25% in the comprehensive modified RND. Neck recurrence rate was no worse in the comprehensive modified RND for N0 and N1 cases, but increased significantly (as compared to the group of patients with standard RND) in the N2 and N3 cases (52% vs. 33%). Treatment of neck recurrences following modified RND was primarily by surgery, with a 48% 3-year disease-free survival. Overall survival was the same for modified RND (68%) and for standard total RND (63%). This was true for all N stages individually. The morbidity of standard total RND is discussed and the goals of modified RND are analyzed. Definitions and a standardized nomenclature for the various types of modified RND are suggested for uniformity of reporting.

A retrospective study on the efficacy of cervical lymph node dissection in well-differentiated carcinoma of the thyroid

The management of cervical lymph node metastases in well-differentiated carcinoma of the thyroid is controversial. In our department, from 1963 to 1972, node plucking was performed only in patients with cervical lymphadenopathy whereas, from 1973 to 1983, modified radical neck dissection was therapeutically or electively performed. In order to determine whether the more extensive dissection is adequate, a retrospective analysis was performed using two groups of patients who were managed differently with regard to the treatment of cervical lymph node metastases. From this series of 206 patients with more than five years follow-up, it was found that the rates of survival and lymph node recurrence did not differ between the two groups. However, since the well-differentiated carcinoma of the thyroid has relatively indolent biological behaviour, further long-term follow-up seems to be necessary for demonstrating the efficacy of neck dissection.

Near-total thyroidectomy for carcinoma of the thyroid

There is controversy about the most appropriate treatment for patients with thyroid cancer. This study analyses our experience with 206 cases of thyroid cancer from an endemic goiterous area. There were 100 males and 106 females; patients presented at an earlier age with a short history. Thyroid cancers demonstrated an aggressive biological behaviour with an advanced stage at presentation (overt cancers in 51 per cent) and a relentless course with a mortality rate of 24.2 per cent for the well-differentiated tumours. Near-total thyroidectomy was performed in 126 patients. Multicentric foci of tumour were seen in 17.2 per cent of the well-differentiated cancers and 25.2 per cent of the cases of well-differentiated cancers who underwent near-total thyroidectomy developed loco-regional recurrence. Hemithyroidectomy was performed in 35 patients who refused completion total thyroidectomy at a second stage; 16.7 per cent of these patients developed a recurrence in the remaining contralateral lobe. Thus in our patients from an endemic goiterous area, near-total thyroidectomy is the treatment of choice particularly because of the frequent occurrence of follicular and anaplastic cancers (in 44.2 per cent) and because the course of the disease is more virulent.