Disease outcomes and nodal recurrence in patients with papillary thyroid cancer and lateral neck nodal metastases

Surgical and Biochemical Outcomes in Nerve Monitored Reoperation Surgery for Recurrent Papillary Thyroid Carcinoma

OBJECTIVE

To study the surgical and biochemical outcomes in nerve-monitored reoperation or revision surgery for recurrent thyroid cancers.

STUDY DESIGN

A single-center retrospective study.

SETTING

Tertiary center.

METHODS

We identified patients with recurrent papillary thyroid carcinoma (PTC) who underwent reoperation/revision surgery. Study outcomes were surgical complications frequency, recurrence, distant metastasis, and biological complete response (BCR) by comparing preoperative and postoperative thyroglobulin (Tg) levels.

RESULTS

Out of 227 patients, 33.9% presented for ≥2 reoperation surgeries. Nineteen (8.4%) had permanent preoperative hypoparathyroidism while 22 patients (9.7%) had preoperative vocal cord paralysis (VCP). Following reoperation surgery, there were 12 cases (5.3%) of permanent hypocalcemia and no cases of unexpected postoperative VCP. BCR was achieved in 31 patients (35.2%) with complete Tg data. Mean preoperative Tg was 47.7 ng/mL and was 19.7 ng/mL postoperatively (p = .003). The cervical nodal recurrence rate after final surgery was 7.0% (n = 16).

CONCLUSION

Reoperation surgery for recurrent PTC may help achieve biochemical remission regardless of age or the number of prior surgeries.

How Many Nodes to Take? Lymph Node Ratio Below 1/3 Reduces Papillary Thyroid Cancer Nodal Recurrence

INTRODUCTION

Papillary thyroid carcinoma (PTC) accounts for the majority of thyroid malignancies; risk of PTC recurrence over a 30-year period is approximately 30%, of which 70% occur as nodal metastases. Patients with nodal disease who are treated with therapeutic dissection are at higher risk for recurrence, but optimal nodal yield has not been defined. We aim to determine variables predictive of nodal recurrence of PTC within the first 5 years of surgery, with a focus on lymph node ratio (LNR), to inform clinical decision-making.

METHODS

Retrospective chart review identified 41 patients with nodal recurrence of PTC and 284 without nodal recurrence following thyroid surgery from 2000 to 2015. Cohorts were compared with regards to clinical history, surgical findings, and tumor characteristics.

RESULTS

The fraction of the patients who underwent therapeutic central or lateral lymph node dissection was significantly higher in the nodal recurrence cohort. Maximum tumor size, presence of extrathyroidal extension, largest lymph node focus, LNR, postoperative thyroglobulin level, and administration of postoperative radioactive iodine were significantly increased in the PTC nodal recurrence group. LNR greater than 0.3 held the highest level of significance as a binary cutoff and captured the larger proportion of patients in the nodal recurrence cohort (68.3%).

CONCLUSION

This study demonstrates characteristics to help assess risk of nodal recurrence of PTC and suggests LNR of lower than 0.3 is optimal to reduce risk of recurrence. The next steps include cohort studies to validate findings and weight variable analysis to optimize the extent of surgical therapeutic dissection.

LEVEL OF EVIDENCE

4 Laryngoscope, 132:1883-1887, 2022.

Recurrent Papillary Thyroid Carcinoma to the Cervical Lymph Nodes: Outcomes of Compartment-Oriented Lymph Node Resection

INTRODUCTION

Recurrence of papillary thyroid carcinoma after initial treatment is challenging. Surgical reintervention is recommended, but cure after surgery in uncertain and surgical morbidity may be high. This study evaluates the effect of compartment-oriented lymph node dissection (LND) on clinical and biochemical cure rate as well as the related complications.

PATIENTS AND METHODS

All patients who underwent LND for recurrent papillary thyroid carcinoma between 2000 and 2015 were included. Demography, the extent of the initial surgery, usage of ¹³¹I, the pattern of recurrence, diagnosis, details of the surgical reintervention, histological findings, surgical morbidity, and clinical and biochemical outcomes were analyzed.

RESULTS

There were 11 (12.7%) males and 75 (87.2%) females with a mean age of 42.8 ± 14.6 years. Seventy-seven patients had undergone total thyroidectomy and in 67 (77.9%) some type of LN resection. In 76 (88.3%), ¹³¹I was administered after the initial surgery. We localized suspicious lymph nodes by US in all patients, and metastases were documented before surgery by FNA in 63. Seven (8.13%) patients underwent central LND, 63 (73.2%) lateral LND and 16 (18.6%) both, central and lateral LND. Major complications occurred in 6 patients (6.9%). Sixty-two (72.0%) patients received ¹³¹I after surgery. A second surgical re-exploration was performed in 30 (34.8%) patients, and 7 patients required 3 or more additional LND. In a mean follow-up of 59.4 ± 39 months, 51 (59.3%) patients are clinically, radiologically and biochemically free of disease.

CONCLUSIONS

In this series, compartment-oriented lymph node resection of recurrent papillary thyroid carcinoma leads to a final clinical and biochemical disease-free status of 59.3% with 6.9% of major complications.

Patterns of Lymph Node Metastasis in Differentiated Thyroid Cancer; Clinical Implications with Particular Emphasis on the Emerging Role of Compartment-Oriented Lymph Node Dissection

Recent advances in modern imaging allow an accurate identification of involved or suspicious lymph nodes within the nodal compartments of the neck. Careful ultrasonographic lymphatic mapping of the neck by an experienced radiologist allows a targeted, compartment-oriented (or selective) lymph node dissection to be performed instead of the more extensive modified radical lymph node dissection. Compartment-oriented lymph node dissection necessitates the close cooperation of an experienced radiologist with a particular interest in thyroid and neck ultrasonography. There is emerging evidence that this more conservative strategy allows local control of the disease while at the same time morbidity is minimized and a better cosmetic result is achieved. Further investigation is needed to establish the precise role of this interesting surgical approach.

Low-Activity Radioactive Iodine Therapy for Thyroid Carcinomas Exhibiting Nodal Metastases and Extrathyroidal Extension May Lead to Early Disease Recurrence

BACKGROUND

The application of radioactive iodine in differentiated thyroid carcinomas has become more selective in an attempt to decrease morbidity. While ablative success has been documented, it is less clear how changes in radioactive iodine treatment strategies will influence long-term recurrence rates for patients with larger tumors and adverse pathological features, including extrathyroidal extension and nodal metastases.

METHODS

Patients diagnosed between 1995 and 2008 with differentiated thyroid carcinoma treated with thyroidectomy followed by radioactive iodine treatment were eligible. All patients were followed for a minimum of five years using a standardized follow-up protocol requiring both biochemical and imaging assessments for recurrent disease (n = 219). Patients were stratified by initial radioactive iodine activity, and disease-free survival was calculated using the Kaplan-Meier method, with significant differences defined by the log-rank test.

RESULTS

In this cohort, 46% of patients had clinical metastases and 74% had primary tumors >1.5 cm. Patients who had recurrences were more likely to present with extrathyroidal extension (p = 0.002) and lymph node metastases at diagnosis (p < 0.001). Patients presenting with both extrathyroidal extension and lymph node metastases had a significantly worse time to progression if treated with <1850 MBq radioactive iodine compared to those patients treated with >1850 MBq (25 months vs. 121 months; p = 0.004). The use of lower-activity radioactive iodine ablative therapy was associated with more early recurrences (p = 0.003). Being aged younger or older than 45 years did not impact the time to recurrence nor did the use of level 6 dissection. On multivariate analysis, lymph node metastases at diagnosis and multiple applications of radioactive iodine were linked to increased risk of recurrence. Patients with neither, or only one, adverse pathologic feature had excellent outcomes, regardless of initial ablative activity, with <10% of patients recurring over a 10-year time span.

CONCLUSIONS

Recurrent disease in differentiated thyroid carcinoma is more common in patients treated with low-activity radioactive iodine in patients with lymph node metastases and extrathyroidal extension. These recurrences typically occur within four years of initial treatment. Patients lacking both of these risk factors treated with low radioactive iodine activity (<1850 MBq) have excellent outcomes, even after 10 years.

Central Lymph Node Dissection Improves Lymph Node Clearance in Papillary Thyroid Cancer Patients with Lateral Neck Metastases, Even after Prior Total Thyroidectomy

The oncologic benefit of a central lymph node dissection (CLND) at the time of modified radical neck dissection (MRND) in patients with papillary thyroid cancer who have previously undergone a total thyroidectomy (TT) has not been studied. Patients with lateral cervical metastases were divided into two treatment groups: the concurrent cohort (TT with CLND and MRND), and the interval cohort (CLND and MRND after prior TT). Primary outcomes were lymph node metastases, skip metastases, level VI cancer recurrence, hypoparathyroidism and recurrent laryngeal nerve injury. Treatment groups consisted of 63 and 16 patients in the concurrent and interval groups, respectively. More central lymph nodes were removed (15.4 ± 8.4 to 10.1 ± 5.2 ( P = 0.02)), but similar level VI lymph node metastasis occurred (92.0–93.8% ( P = 0.99)) in the concurrent group compared with the interval group, respectively. Skip metastases were identified in only 7.6 per cent of patients. The incidence of level VI recurrence and recurrent laryngeal nerve injury was 1.2 per cent. Three patients developed hypoparathyroidism (3.7%). All permanent morbidities occurred in the concurrent group. CLND at the time of MRND for metastatic papillary thyroid cancer frequently identifies level VI metastases and can be done with low operative morbidity by experienced endocrine surgeons, even in patients who have undergone a prior TT.

Higher preablative serum thyroid-stimulating hormone level predicts radioiodine ablation effectiveness in patients with differentiated thyroid carcinoma

INTRODUCTION

Radioiodine ablation of remnant thyroid tissue is an important adjuvant therapy of differentiated thyroid carcinoma (DTC) after thyroidectomy. Elevated serum thyroid-stimulating hormone (TSH) level is necessary for successful ablation. The optimum level of serum TSH level necessary for successful radioiodine ablation of well-DTC is, however, yet to be defined. We aimed to determine whether higher serum TSH level will result in a better rate of complete ablation of well-DTC using iodine-131 (I) following initial thyroidectomy.

PATIENTS AND METHODS

A total of 109 patients with differentiated thyroid cancer were divided into four treatment groups on the basis of serum TSH levels. They were followed up from 6 to 12 months after treatment with stimulated serum thyroglobulin level and a diagnostic whole-body scan with radioactive iodine I to determine early response.

RESULTS

Sixty-four patients had papillary thyroid carcinoma, whereas 45 patients had follicular carcinoma. An excellent response was observed in 66.7% of patients with TSH level more than 90 μIU/ml, 72.2% in the group with TSH level of 60-89 μIU/ml, 48.5% when TSH was 30-59 μIU/ml and 26.7% when TSH was less than 30 μIU/ml (P=0.002).

CONCLUSION

Higher preablative serum TSH predicts a better rate of ablation in patients with differentiated thyroid cancer treated with I after thyroidectomy.

Recombinant human TSH versus thyroid hormone withdrawal in adjuvant therapy with radioactive iodine of patients with papillary thyroid carcinoma and clinically apparent lymph node metastases not limited to the central compartment (cN1b)

Objective

To compare the short- and long-term outcomes of adjuvant therapy with radioactive iodine (RAI) preceded by the administration of recombinant human TSH (rhTSH) versus thyroid hormone withdrawal (THW) in patients with papillary thyroid carcinoma and clinically apparent lymph node metastases not limited to the central neck compartment (cN1b).

Subjects and methods

The sample consisted of 178 cN1b patients at intermediate risk who underwent total thyroidectomy with apparently complete tumor resection [including postoperative ultrasonography (US) without anomalies] and who received adjuvant therapy with RAI (30-100 mCi) preceded by the administration of rhTSH (n = 91) or THW (n = 87).

Results

One year after RAI, the rates of excellent response to therapy, i.e., nonstimulated thyroglobulin (Tg) ≤ 0.2 ng/mL with negative antithyroglobulin antibodies and negative neck US, and of structural disease were similar for the two preparations (84% and 4.5%, respectively, in both groups). During follow-up (median 66 months), the rate of structural or biochemical (nonstimulated Tg > 1 ng/mL, with increment) recurrence was also similar in the two groups (4.5%). In the last assessment, the percentage of patients without evidence of disease, i.e., nonstimulated Tg < 1 ng/mL and no evidence of structural disease, was similar for the two preparations [92.3% in the rhTSH group and 97.7% in the THW group (p = 0.17)].

Conclusion

Preparation with rhTSH was equally effective (short- and long-term) as THW for adjuvant RAI therapy of cN1b patients at intermediate risk and with apparently complete tumor resection.

Pattern of neck recurrence after lateral neck dissection for cervical metastases in papillary thyroid cancer

BACKGROUND

The objective of this study was to determine the rate and pattern of nodal recurrence in patients who underwent a therapeutic, lateral neck dissection (LND) for papillary thyroid cancer (PTC) with clinically evident cervical metastases and to determine if there was any correlation between the extent of initial dissection and the rate and pattern of neck recurrence.

METHODS

A total of 3,664 patients with PTC treated between 1986 and 2010 at Memorial Sloan Kettering Cancer Center were identified from our institutional database. Tumor factors, patient demographics, extent of initial LND, and adjuvant therapy were recorded. Patterns of recurrent lateral neck metastases by level involvement were recorded and outcomes calculated using the Kaplan-Meier method.

RESULTS

A total of 484 patients had an LND for cervical metastases; 364 (75%) had a comprehensive LND (CLND) and 120 (25%) had a selective neck dissection (SND). The median duration of follow-up was 63.5 months. As expected, patients with CLND had a greater number of nodes removed as well as a greater number of positive nodes (P < .001). There was no difference in overall lateral neck recurrence-free status (CLND 94.4% vs SND 89.4%, P = .158), but in the dissected neck, the ipsilateral lateral neck recurrence-free status was superior in the CLND patients (97.7% vs 89.4%, P < .001).

CONCLUSION

Patients with clinically evident neck metastases from PTC managed by CLND have lesser rates of recurrence in the dissected neck compared with patients managed by SND. SND should only be done in highly selected cases with small volume disease.

Cervical lymph node metastasis in differentiated thyroid carcinoma: does it have an impact on disease-related morbid events?

PURPOSE

The aim of the study was to evaluate the prognostic impact of cervical lymph node (CLN) metastasis in well-differentiated thyroid cancer (WDTC).

PATIENTS AND METHODS

A cohort of 164 patients who underwent thyroidectomy for WDTC in the last 12 years was studied. Patients were classified into those with CLN metastasis (group 1) and those without (group 2), with 82 patients in each group. Morbid events (recurrence and death) and prognostic risk factors were analyzed.

RESULTS

The mean age of the whole group was 41.3±14.2 years, with 52.4% being at least 45 years old; 69.6% of the patients were female (P=0.02), with a female to male ratio of 2.3 : 1. Near-total thyroidectomy and radioactive iodine-131 therapy were performed in all 81.1% of patients in whom papillary cancer was found. Morbid events were found in 22/164 (13.4%) patients (17 recurrences and five deaths). All recurrences occurred in patients with the papillary subtype, whereas 4/5 deaths occurred in those with follicular thyroid cancer. Morbid events were found in 14/82 (17.1%) and 8/82 (9.6%) patients in group 1 and group 2, respectively (P=0.1). Comparison of morbid events between group 1 and group 2 showed statistically significant differences with respect to tumor size of 1 cm or more, multifocality, and positivity of the follow-up diagnostic tools at 6-12 months. Kaplan-Meier analysis revealed no significant difference between the two groups (P=0.4) over a mean follow-up period of 125.1±14.6 months. Multivariate Cox analysis showed that development of remote deposits, lymph node metastasis five or more nodes, extracapsular nodal invasion in at least three nodes, and positivity of the follow-up diagnostic tools at 6 months were the significant prognostic factors of morbid events.

CONCLUSION

Our study revealed the impact of CLN metastasis on the occurrence of morbid events in WDTC patients (especially in those with the papillary subtype) with node metastasis five or more, extracapsular nodal invasion in at least three nodes, and positivity of follow-up diagnostic tools at 6 months. Hence, these patients should be optimally managed and more closely monitored.

Non-thermal atmospheric pressure plasma inhibits thyroid papillary cancer cell invasion via cytoskeletal modulation, altered MMP-2/-9/uPA activity

Plasma, the fourth state of matter, is defined as a partially or completely ionized gas that includes a mixture of electrons and ions. Advances in plasma physics have made it possible to use non-thermal atmospheric pressure plasma (NTP) in cancer research. However, previous studies have focused mainly on apoptotic cancer cell death mediated by NTP as a potential cancer therapy. In this study, we investigated the effect of NTP on invasion or metastasis, as well as the mechanism by which plasma induces anti-migration and anti-invasion properties in human thyroid papillary cancer cell lines (BHP10-3 and TPC1). Wound healing, pull-down, and Transwell assays demonstrated that NTP reduced cell migration and invasion. In addition, NTP induced morphological changes and cytoskeletal rearrangements, as detected by scanning electron microscopy and immunocytochemistry. We also examined matrix metalloproteinase (MMP)-2/-9 and urokinase-type plasminogen activator (uPA) activity using gelatin zymography, uPA assays and RT-PCR. FAK, Src, and paxillin expression was detected using Western blot analyses and immunocytochemistry. NTP decreased FAK, Src, and paxillin expression as well as MMP/uPA activity. In conclusion, NTP inhibited the invasion and metastasis of BHP10-3 and TPC1 cells by decreasing MMP-2/-9 and uPA activities and rearranging the cytoskeleton, which is regulated by the FAK/Src complex. These findings suggest novel actions for NTP and may aid in the development of new therapeutic strategies for locally invasive and metastatic cancers.

Markedly elevated thyroglobulin levels in the preoperative thyroidectomy patient correlates with metastatic burden

BACKGROUND

Thyroglobulin (Tg) is a marker of tumor recurrence during thyroid cancer follow-up. While helpful in the postoperative setting, the clinical significance of preoperative Tg measurements remains unclear. The aim of the study was to determine if preoperative Tg levels are indicative of underlying malignancy or burden of metastatic disease.

METHODS

A retrospective review of a prospectively collected database at an academic medical center of all thyroidectomy patients with a measured preoperative Tg level was conducted. Patients were grouped by Tg level into quartiles for initial univariate analysis, followed by multivariable analysis of variance.

RESULTS

Between 2007 and 2012, 611 patients met criteria. Quartile breakdown was as follows: ≤19 ng/mL, 19.1-54 ng/mL, 54.1-151 ng/mL, and >151 ng/mL. Patients' age and gender were equivalent. Hashimoto's thyroiditis was most common in the lowest Tg group (24% versus 11%-12%, P < 0.01). While cancer was more common in the low Tg, metastatic disease was most common in the high Tg group. Specimen weight increased with increasing Tg levels (P < 0.01). Body mass index, gland weight, cancer, and Hashimoto's and metastatic disease were entered into a multivariable analysis. Only gland weight and metastatic disease correlated with Tg levels (both P < 0.001). All patients with Tg > 5000 ng/mL had metastatic disease (n = 6).

CONCLUSIONS

Although preoperative Tg levels are not associated with a diagnosis of cancer, they are associated with the presence of metastatic disease. All patients with a Tg > 5000 ng/mL had significant disease burden. In patients with concern for metastatic disease, preoperative serum Tg may be a useful marker to aid decision making.