Factors influencing morbidity after surgical management of malignant thyroid disease

Recurrent laryngeal never monitoring versus non-monitoring in parathyroid surgery

Background

Although intraoperative neural monitoring (IONM) is well established in thyroid surgery, it is less commonly analyzed in parathyroid operations. This study presents the results of IONM for primary and secondary hyperparathyroidism surgery.

Methods

We retrospectively assessed 270 patients with primary hyperparathyroidism (PHPT), 53 patients with secondary hyperparathyroidism (SHPT), and 300 patients with thyroid cancer from June 2010 to June 2022 in one hospital in China. The follow-up was 12 months. Demographic, electromyography data from IONM, laboratory, and clinical information were collected. Laryngoscopy was collected from 109 patients with PHPT in whom IONM was not used. All groups were assessed by Pearson's chi-square test and Fisher's exact probability method to verify the relationship between parathyroid size and location, duration of surgery, preoperative concordant localization, laryngeal pain, IONM outcomes, cure rate, and RLN injury. Visual analog scale (VAS) assessed laryngeal pain. RLN outcomes were measured according to nerves at risk (NAR).

Results

The study comprehended 918 NAR, that is 272, 105, 109, and 432 NAR for PHPT, SHPT with IONM, PHPT without IONM, and thyroid surgery control group, respectively. IONM successfully prevented RLN injury (P<0.001, P=0.012): Fifteen (5.51%) RLNs experienced altered nerve EMG profiles during surgery, and five (1.84%) experienced transient RLN injury in PHPT patients. Five (4.76%) RLNs were found to have altered EMG profiles during surgery, and one (0.95%) RLN had a transient RLN injury in SHPT patients. There was no permanent nerve injury (0.00%) in this series. There was no association between location, gland size, preoperative concordant localization, cure rate, duration of surgery, and IONM (P >0.05). Duration of surgery was associated with postoperative pharyngeal discomfort (P=0.026, P=0.024). Transient RLN injury was significantly lower in patients with PHPT who underwent IONM than in those who did not. Intraoperative neuromonitoring played an effective role in protecting the recurrent laryngeal nerve (P=0.035). Compared with parathyroidectomy, thyroidectomy had a higher rate of RLN injury (5.32%, P<0.001).

Conclusion

IONM for SHPT and PHPT offers rapid anatomical gland identification and RLN functional results for effective RLN protection and reduced RLN damage rates.

Is There Any Reliable Predictor of Functional Recovery Following Post-thyroidectomy Vocal Fold Paralysis?

BACKGROUND

Predicting definitive outcomes of post-thyroidectomy vocal fold paralysis (VFP) is challenging. We aimed to identify reliable predictors based on intraoperative neuromonitoring (IONM) and flexible fiberoptic laryngostroboscopy (FFL) findings.

METHODS

Among 1172 thyroid operations performed from April to December 2021, all patients who exhibited vocal fold paralysis (VFP) at post-operative laryngoscopy were included. IONM data, including type of loss of signal (LOS), were collected. Patients underwent FFL, with arytenoid motility assessment, at 15, 45 and 120 days post-operatively. Patients were divided into two groups: those who recovered vocal fold motility (VFM) by the 120th post-operative day (recovery group) and those who did not (non-recovery group).

RESULTS

Fifty-nine VFP cases (5.0% of total patients) met the inclusion criteria. Eight patients were lost at follow-up and were excluded. Overall, 9 patients were included in the non-recovery group (0.8% of total patients) and 42 in the recovery group. Among various predictive factors, only arytenoid fixation (AF) at the 15th post-operative day and Type I LOS were significant predictors for no VFM recovery (p = 0.007, RR = 9.739, CI:1.3-72.3 and p = 0.001, RR = 9.25, CI:2.2-39.3 for AF and Type I injury, respectively). The combination of type of LOS and arytenoid motility at the 15th post-op day yielded satisfactory predictive values for the progression of transient VFP to permanent.

CONCLUSIONS

Arytenoid motility at the 15th post-op day and type II LOS are associated with recovery of VFM. Type of LOS and FFL could be included in the follow-up protocols of patients with VFP to reliably predict clinical outcomes.

Risk factors for difficult thyroidectomy and postoperative morbidity do not match: retrospective study from an endocrine surgery academic referral centre

Hyperthyroidism, goiter and thyroiditis have been associated with complex thyroidectomy. Difficult thyroidectomies may implicate longer operating times and higher complication rates, while literature on quantification and prediction of difficulty in thyroidectomy is scant. We aim at assessing the impact of preoperative and intraoperative factors on the technical difficulty of total thyroidectomy (TT) and on the incidence of postoperative complications. We conducted a retrospective study on 197 TT from 343 thyroidectomies performed with intraoperative neuromonitoring between October 2019 and June 2022 (excluding lobectomies, nodal dissection, extra-thyroidal procedures). Operating time (surrogate of TT difficulty), postoperative hypocalcaemia, recurrent laryngeal nerve palsy and postoperative bleeding were assessed in relation to pre- and intraoperative characteristics. Vocal fold palsy(VFP) was defined as recovering < 12 months postoperatively. There were 87 thyroid cancers and 110 multinodular goiters (21 hyperfunctioning, 51 mediastinal). Median operating time was 136 min (range 51-310). Within 17.4 months overall median follow-up we recorded two transient VFPs and 12% symptomatic transient hypocalcaemia. At univariable analysis male sex (p = 0.005), BMI (p < 0.001), thyroiditis (p < 0.05), hypervascular goiter (p = 0.003) and thyroid adhesions to surrounding anatomical structures (p < 0.001) were associated with longer operating time. At multivariable analysis male male sex (p = 0.01), obesity (p = 0.001) and thyroid adhesions (p = 0.008) were factors for prolonged operating time. Above-normal anti-thyroid peroxidase antibodies correlated to transient symptomatic hypocalcemia (p < 0.001). Risk factors for complex TT were identified and did not correlate with morbidity rates. Results from this study may help optimizing operating room schedule and inform case selection criteria for training programs in thyroid surgery. Further research is required to confirm these findings.

Medial Approach for Identification of Recurrent Laryngeal Nerve in Locally Advanced Differentiated Thyroid Carcinoma: Revisited

Recurrent laryngeal nerve injury is a well-recognized and potentially catastrophic complication of thyroidectomy. In literature, four approaches have been described for identification of RLN, the superior, lateral, medial, and inferior approaches. But medial approach is lesser known amongst surgeons. Locally infiltrative thyroid cancer with extensive lymph nodal metastasis in central and lateral compartment sometimes makes it difficult to identify RLN by any of these standard approaches described above. A medial approach was described where RLN is identified as it extends up to interdigitate with the trunk or the branches of the inferior thyroid artery. We present here a new alternative technique for identification of recurrent laryngeal nerve through modified medial approach that was used in difficult thyroidectomies.

Clinical advantages and neuroprotective effects of monitor guided fang's capillary fascia preservation right RLN dissection technique

OBJECTIVE

To investigate the feasibility and advantages of Fang's capillary fascia preservation right recurrent laryngeal nerve (RLN) dissection technique (F-R-RLN dissection) with preservation of the capillary network and fascia between the RLN and common carotid artery for greater neuroprotective efficiency compared with traditional techniques.

METHODS

We retrospectively analyzed 102 patients with papillary thyroid carcinoma undergoing right level VI lymph node dissection in our department from March 2021 to January 2022. Sixty patients underwent F-R-RLN dissection (the experimental group) and 42 patients underwent standard dissection (the control group). The intraoperative electrical signal amplitude ratios of the RLN, the number of dissected lymph nodes, and the preservation rates of the parathyroid glands were recorded and compared between the two groups.

RESULTS

The electrical signal amplitude ratio of the lower neck part point of the RLN to the upper laryngeal inlet point in the experimental group was significantly lower than the ratio in the control group (p = 0.006, Z-score = -2.726). One patient suffered transient RLN paralysis in both groups, but this resolved within 1 month after operation. There were no significant differences between the two groups in terms of the number of level VIa or level VIb lymph nodes dissected, nor in the rate of preservation of the parathyroid glands.

CONCLUSIONS

F-R-RLN dissection is a thorough dissection technique that is effective at preventing an electrical signal amplitude decrease in the RLN, and at preventing RLN paralysis by preserving its blood supply.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Controversies in the Management of Low-Risk Differentiated Thyroid Cancer

Controversy exists over optimal management of low-risk differentiated thyroid cancer. This controversy occurs in all aspects of management, including surgery, use of radioactive iodine for remnant ablation, thyroid hormone supplementation, and long-term surveillance. Limited and conflicting data, treatment paradigm shifts, and differences in physician perceptions contribute to the controversy. This lack of physician consensus results in wide variation in patient care, with some patients at risk for over- or undertreatment. To reduce patient harm and unnecessary worry, there is a need to design and implement studies to address current knowledge gaps.

Cost-Effectiveness of Long-Term Every Three-Year Versus Annual Postoperative Surveillance for Low-Risk Papillary Thyroid Cancer

BACKGROUND

Patients with low-risk papillary thyroid cancer (PTC) who demonstrate an excellent response to initial therapy have a 2% recurrence rate and 100% disease-specific survival within 10 years. Thus, annual surveillance may be excessive. We hypothesized that less frequent postoperative surveillance in these patients is cost effective.

METHODS

A Markov discrete time state transition model was created to compare postoperative surveillance tapered to 3-year intervals after 5 years of annual surveillance versus conventional annual surveillance in low-risk PTC patients with negative neck ultrasound and stimulated thyroglobulin less than 2 ng/mL 1 year postoperatively. Outcome probabilities, utilities, and costs were determined via literature review, the Medicare Physician Fee Schedule, and Healthcare Cost and Utilization Project data. Sensitivity analyses were performed to assess areas of uncertainty.

RESULTS

The cost of annual surveillance was $5,239 per patient and yielded 22.49 quality-adjusted life-years (QALYs). The 3-year strategy cost $2,601 less, but also yielded 0.01 less QALYs. Thus, the incremental cost per QALY of annual surveillance was $260,100. Probabilistic sensitivity analysis demonstrated that less frequent surveillance was more cost effective in 99.98% of 10,000 simulated patients. One-way sensitivity analysis revealed that annual surveillance would be cost effective if the total cost of neck ultrasound could be reduced to $23 or less.

CONCLUSION

Extending postoperative surveillance to 3-year intervals after 5 years of annual surveillance in patients with low-risk PTC with excellent response to therapy is more cost effective than annual surveillance.

Evaluation of the clinical value of carbon nanoparticles as lymph node tracer in differentiated thyroid carcinoma requiring reoperation

BACKGROUND

The incidence of parathyroid injury in patients with differentiated thyroid carcinoma (DTC) who underwent reoperation is significantly higher than that incurred from the initial surgery. The aim of this study was to investigate the clinical value of carbon nanoparticles (CN) as tracers for lymph nodes to guide cervical lymph node dissection and protect the parathyroid during reoperation for DTC.

METHODS

Our study recruited 116 patients with DTC who previously underwent thyroidectomy and later received remedial surgical treatment at the Department of Breast and Thyroid Surgery, Hunan Provincial People's Hospital, China, between February 2011 and February 2014. Those patients were randomly divided into the experimental group (the CN group) with 64 cases and the control group with 52 cases. Carbon nanoparticle suspension (CNS, 0.1-0.3 ml) was intraoperatively injected into the residual thyroid or enlarged lymph nodes in the CN group; in the control group, CNS was not applied intraoperatively. The differences in identification of the parathyroid glands, the number of lymph nodes resected intraoperatively, and the incidence of common complications after thyroidectomy in both groups were recorded and analyzed.

RESULTS

The accuracy of identification of the parathyroid in the CN group and control group was 92.2 % and 28.8 %, respectively, and the identification rate of three glands or more in both groups was 75 % and 36.5 %, respectively; those differences were statistically significant between the two groups (P < 0.05). There was also a significant difference between the two groups in the number of lymph nodes removed in the central and lateral cervical compartments (P < 0.05). There was no increase in common complications after the second surgery compared with the previous surgery; in addition, there was a decline in the incidence of transient hypoparathyroidism (HPT) (P < 0.05).

CONCLUSIONS

By tracing the thyroid and cervical regional lymph nodes with carbon nanoparticles, the parathyroid glands can be easily identified and protected to reduce the complications of transient hypoparathyroidism resulting from reoperation for residual or missed DTC. Carbon nanoparticle tracers also facilitate radical resection of lymph nodes at the central and lateral compartments of the neck.

Differentiated thyroid cancer in people aged 85 and older

OBJECTIVES

To describe the characteristics and treatment patterns of differentiated thyroid cancer in older adults.

DESIGN

Retrospective cohort study.

SETTING

The National Cancer Institute Surveillance, Epidemiology, and End Results database.

PARTICIPANTS

Individuals age 85 and older with a primary thyroid cancer diagnosis of papillary or follicular histology diagnosed between 1988 and 2007 (N=424).

MEASUREMENTS

Age, sex, histology, extent of disease, tumor size, treatment, type of surgery, cause of death, and length of survival.

RESULTS

Tumor size and extent of disease were significantly related to cause of death (P=.02). Participants who did not have surgery were more likely to die of their thyroid cancer than of any other cause (P=.01), and whether a participant had surgery was significantly related to age (P=.002). Participants who had surgery had significantly longer survival than those who did not (P<.001). Type of surgery (P=.92) and adding radioactive iodine after surgery (P=.07) did not appear to influence length of survival.

CONCLUSION

Although differentiated thyroid cancer is typically considered a relatively indolent disease, this is not the case in older adults. Surgery appears to reduce the likelihood of death from thyroid cancer in this population and confers a survival benefit. Type of surgery and adding radioactive iodine therapy do not seem to improve the survival benefit of surgical management.

Identifying predictors of a difficult thyroidectomy

BACKGROUND

A Thyroidectomy Difficulty Scale (TDS) was previously developed that identified more difficult operations, which correlated with longer operative times and higher complication rates. The purpose of this study was to identify preoperative variables predictive of a more difficult thyroidectomy using the TDS.

METHODS

A four item, 20-point TDS, was used to score the difficulty of thyroid operations. Patient and disease factors were recorded for each patient. Difficult thyroidectomy and non-difficult thyroidectomy (NDT) patients were compared. A final multivariate logistic regression model was constructed with significant (P<0.05) variables from a univariate analysis.

RESULTS

A total of 189 patients were scored using TDS. Of them, 69 (36.5%) suffered from hyperthyroidism, 42 (22.2%) from Hashimotos, 34 (18.0%) from thyroid cancer, and 36 (19.0%) from multinodular goiter. Among hyperthyroid patients, the DT group had a greater number preoperatively treated with Lugols potassium iodide (81.6% DT versus 58.1% NDT, P=0.032), presence of ophthalmopathy (31.6% DT versus 9.7% NDT, P=0.028), and presence of (>4 IU/mL) antithyroglobulin antibodies (34.2% DT versus 12.9% NDT, P=0.05). Using multivariate analysis, hyperthyroidism (odds ratio [OR], 4.35, 95% confidence interval [CI], 1.23-15.36, P=0.02), presence of antithyroglobulin antibody (OR, 3.51, 95% CI, 1.28-9.66, P=0.015), and high (>150 ng/mL) thyroglobulin (OR, 2.61, 95% CI, 1.06-6.42, P=0.037) were independently associated with DT.

CONCLUSIONS

Using TDS, we demonstrated that a diagnosis of hyperthyroidism, preoperative elevation of serum thyroglobulin, and antithyroglobulin antibodies are associated with DT. This tool can assist surgeons in counseling patients regarding personalized operative risk and improve OR scheduling.