The use of Callitriche cophocarpa Sendtn. for the reclamation of Cr-contaminated freshwater habitat: benefits and limitations.

This work is the first attempt to evaluate suitability of Callitriche cophocarpa Sendtn. (water-starwort) to remove Cr under real-world conditions. Our earlier laboratory-scale studies demonstrated outstanding hyperaccumulation properties of this aquatic higher plant (macrophyte) toward chromium in solution. We introduced C. cophocarpa plants into the watershed with sediments heavily polluted (on average 1400 mg/kg d.w. of Cr) by a tannery. The plants grew vigorously and exhibited no physiological or anatomical disorders. Based on chemical fractionations of bottom sediments, we found low Cr bioavailability. The element was strongly associated with the sediments and could be classified into the following fractions (%): oxidizable III (68.2) > residual IV (28.8) > reducible II (1.6) > exchangeable I (1.4). Despite this, Cr content in plant organs at the contaminated sites was 33 up to 83 times greater than in the control leaf/stem and roots, respectively. Altering redox potential during, i.e., sediment deposition on land may change chemical forms of bound metals in a solid phase, and thus further increase Cr phytoextraction by plants. With this in mind, we concluded that the species, being an outstanding Cr accumulator under laboratory conditions, can be useful in the reclamation of Cr-polluted sediments under controlled, oxidizing conditions.

Prognostic value of intraoperative neural monitoring of the recurrent laryngeal nerve in thyroid surgery.

PURPOSE: The diagnostic accuracy of intraoperative recurrent laryngeal nerve (RLN) monitoring (IONM) remains controversial. The aim of this study was to evaluate IONM diagnostic accuracy in prognostication of postoperative nerve function in thyroid surgery. METHODS: This prospective study was conducted in 2011-2013. Five hundred consenting patients qualified for total thyroidectomy with IONM (1000 nerves at risk) using NIM 3.0 Response equipment were included. Laryngoscopy was used to evaluate and follow up RLN injury. The primary outcome was diagnostic accuracy of IONM. The receiver operating characteristics (ROC) were used for evaluation of IONM diagnostic accuracy. RESULTS: Loss of signal (LOS) occurred in 31 cases, including 25 patients with LOS and corresponding vocal fold paresis found in postoperative laryngoscopy (2.5 %), including 20 (2.0 %) temporary and 5 (0.5 %) permanent nerve lesions. The following diagnostic accuracy values were calculated for the criterion recommended by INMSG (V2 amplitude ≤ 100 µV): sensitivity 92.0 %, specificity 99.3 %, positive predictive value (PPV) 76.7 %, and negative predictive value (NPV) 99.8 %. The ROC curve analysis allowed for calculation of the most optimal criterion in prognostication of postoperative vocal fold paresis, namely, V2 amplitude ≤ 189 µV. For this criterion, PPV was 77.4 %, while NPV was 99.9 %. CONCLUSIONS: Adherence to the standardized protocol recommended by the International Neural Monitoring Study Group allows for optimizing predictive values of IONM in prognostication of postoperative RLN function. Any changes in the cutoff values for the definition of LOS only marginally improve PPV and NPV of IONM and need to be carefully assessed in multicenter studies.

Subtotal parathyroidectomy for secondary renal hyperparathyroidism: a 20-year surgical outcome study.

AIM: The aim of this study was to evaluate the outcomes of surgery for patients with secondary renal hyperparathyroidism (rHPT). METHODS: This is a retrospective cohort study. Our institutional database was searched for eligible patients treated in 1995-2014. The inclusion criterion was initial parathyroidectomy for rHPT. Clinical and follow-up data were analyzed to estimate the cure rate (primary outcome), and morbidity (secondary outcome). RESULTS: The study group comprised 297 patients (154 females, age 44.5 ± 13.7 years, follow-up 24.6 ± 10.5 months), including 268 (90.2 %) patients who had underwent subtotal parathyroidectomy, and 29 (9.8 %) who had had incomplete parathyroidectomy. Intraoperative iPTH assay was utilized in 207 (69.7 %) explorations. Persistent rHPT occurred in 12/268 (4.5 %) patients after subtotal parathyroidectomy and 5/29 (17.2 %) subjects after incomplete parathyroidectomy (p = 0.005). The patients operated on with intraoperative iPTH assay had a higher cure rate than non-monitored individuals, 201/207 (97.1 %) vs. 79/90 (87.8 %), respectively (p = 0.001). In-hospital mortality occurred in 1/297 (0.3 %) patient. The hungry bone syndrome occurred in 84/268 (31.3 %) patients after subtotal parathyroidectomy and 2/29 (6.9 %) subjects after incomplete parathyroidectomy (p = 0.006). Transient recurrent laryngeal nerve paresis occurred in 14/594 (2.4 %) and permanent in 5/594 (0.8 %) nerves at risk. CONCLUSIONS: Subtotal parathyroidectomy is a safe and efficacious treatment for patients with rHPT. Utilization of intraoperative iPTH assay can guide surgical exploration and improve the cure rate.

Trends in Prevalence of Thyroid Cancer Over Three Decades: A Retrospective Cohort Study of 17,526 Surgical Patients.

INTRODUCTION: Thyroid cancer (TC) incidence has been increasing in recent years. The aim of this study was to investigate our institution-based estimates of operative volumes for TC over the last three decades. MATERIALS AND METHODS: This was a retrospective cohort study of patients undergoing thyroid surgery at our institution. Patient characteristics were reviewed in three subgroups: Group I (treated in 1981-1986), Group II (treated in 1987-2002), and Group III (treated in 2003-2012). RESULTS: TC was diagnosed in 1578/17,526 (9.0%) thyroid operations. Incidence of TC increased from 3.7% in Group I to 10.4% in Group III (p < 0.001). Incidence of papillary TC increased form 40.6% in Group I to 81.3% in Group III (p < 0.001). In the latter group, 23.5% of all papillary TCs were diagnosed in patients with Hashimoto's disease. Meanwhile, incidence of anaplastic TC decreased from 16.2% in Group I to 2.1% in Group III patients (p < 0.001). pT1 tumors were diagnosed in 8.1% Group I and 54.8% Group III (p < 0.001), whereas pT4 tumors were identified in 40.5% Group I, 2.4% Group II, and 0.84% Group III subjects (p < 0.001). pT3 tumors were found in 51.6% Group I, whereas multifocal papillary TCs were found in 15.7% Group III patients, the latter with a higher prevalence of pN1 stage (p < 0.001). CONCLUSIONS: The following trends in surgical volume for TC were identified throughout the study period: a fivefold increase of thyroid operations for TC, a threefold increase in incidence of papillary TC, and an eightfold decrease in incidence of anaplastic TC. It is of interest that a significant increase in incidence of multifocal papillary TC in young female patients with Hashimoto's disease was found over time.

The Overwhelming Majority but not All Motor Fibers of the Bifid Recurrent Laryngeal Nerve are Located in the Anterior Extralaryngeal Branch.

BACKGROUND: Few small studies reported that motor fibers are located exclusively in the anterior branch of the bifid recurrent laryngeal nerve (RLN). The aim of this study was to investigate the location of the motor fibers to the intrinsic muscles of the larynx among the bifid RLNs, and assess the prevalence of RLN injury with respect to nerve branching in a pragmatic trial. METHODS: This was a prospective cohort study of 1250 patients who underwent total thyroidectomy with intraoperative neural monitoring. The primary outcome was the position of the motor fibers in the bifid nerves. Adduction of the vocal folds was detected by the endotracheal tube electromyography and abduction by finger palpation of muscle contraction in the posterior cricoarytenoid. The secondary outcomes were the prevalence of the RLN branching and the prevalence of RLN injury in bifid versus non-bifid nerves. RESULTS: The bifid RLNs were identified in 613/2500 (24.5%) nerves at risk, including 92 (7.4%) patients with bilateral bifurcations. The motor fibers were present exclusively in the anterior branch in 605/613 (98.7%) bifid nerves, and in both the RLN branches in 8/613 (1.3%) bifid nerves. Prevalence of RLN injury was 5.2 versus 1.6% for the bifid versus non-bifid nerves (p < 0.001), odds ratio 2.98 (95% confidence interval 1.79-4.95; p < 0.001). CONCLUSIONS: The motor fibers of the RLN are located in the anterior extralaryngeal branch in the vast majority of but not in all patients. In rare cases, the motor fibers for adduction or abduction are located in the posterior branch of the RLN. As the bifid nerves are more prone to injury than non-branched nerves, meticulous dissection is recommended to assure preservation of all the branches of the RLN during thyroidectomy.

Nodal recurrence in the lateral neck after total thyroidectomy with prophylactic central neck dissection for papillary thyroid cancer.

PURPOSE: The aim of this study was to examine risk factors for nodal recurrence in the lateral neck (NRLN) in patients with papillary thyroid cancer (PTC) who underwent total thyroidectomy with prophylactic central neck dissection (TT + pCND). METHODS: This was a retrospective cohort study of patients with PTC who underwent TT + pCND. Data of all patients treated over a 10-year period (between 1998 and 2007) were analysed. The primary outcome was prevalence of NRLN within the 5-year follow-up after initial surgery. Predictors of NRLN were determined in the univariable and multivariable analysis. RESULTS: Of 760 patients with PTC included in this study, 44 (6.0 %) developed NRLN. In the univariable analysis, the following factors were identified to be associated with an increased risk of NRLN: positive/negative lymph node ratio ≥0.3 (odds ratio (OR) 14.50, 95 % confidence interval (CI) 7.21 to 29.13; p < 0.001), central lymph node metastases (OR 7.47, 95 % CI 3.63 to 15.38; p < 0.001), number of level VI lymph nodes <6 in the specimen (OR 2.88, 95 % CI 1.21 to 6.83; p = 0.016), extension through the thyroid capsule (OR 2.55, 95 % CI 1.21 to 5.37; p = 0.013), localization of the tumour within the upper third of the thyroid lobe (OR 2.35, 95 % CI 1.27 to 4.34; p = 0.006) and multifocal lesions (OR 1.85, 95 % CI 1.01 to 3.41; p = 0.048). CONCLUSIONS: Central lymph node metastases together with positive to negative lymph node ratio ≥0.3 represent the strongest independent prognostic factors for the PTC recurrence in the lateral neck.

Intraoperative nerve monitoring can reduce prevalence of recurrent laryngeal nerve injury in thyroid reoperations: results of a retrospective cohort study.

BACKGROUND: The prevalence of recurrent laryngeal nerve (RLN) injury is higher in repeat than in primary thyroid operations. The use of intraoperative nerve monitoring (IONM) as an aid in dissection of the scar tissue is believed to minimize the risk of nerve injury. The aim of this study was to examine whether the use of IONM in thyroid reoperations can reduce the prevalence of RLN injury. METHODS: This was a retrospective cohort study of patients who underwent thyroid reoperations with IONM versus with RLN visualization, but without IONM. The database of thyroid surgery was searched for eligible patients (treated in the years 1993-2012). The primary outcomes were transient and permanent RLN injury. Laryngoscopy was used to evaluate and follow RLN injury. RESULTS: The study group comprised 854 patients (139 men, 715 women) operated for recurrent goiter (n = 576), recurrent hyperthyroidism (n = 36), completion thyroidectomy for cancer (n = 194) or recurrent thyroid cancer (n = 48), including 472 bilateral and 382 unilateral reoperations; 1,326 nerves at risk (NAR). A group of 306 patients (500 NAR) underwent reoperations with IONM and 548 patients (826 NAR) had reoperations with RLN visualization, but without IONM. Transient and permanent RLN injuries were found respectively in 13 (2.6 %) and seven (1.4 %) nerves with IONM versus 52 (6.3 %) and 20 (2.4 %) nerves without IONM (p = 0.003 and p = 0.202, respectively). CONCLUSIONS: IONM decreased the incidence of transient RLN paresis in repeat thyroid operations compared with nerve visualization alone. The prevalence of permanent RLN injury tended to be lower in thyroid reoperations with IONM, but statistical validation of the observed differences requires a sample size of 920 NAR per arm.

[Staging of thyroid cancer--comparison of cases diagnosed preoperatively versus incidentally after surgery for benign goiter]. / Porównanie stopnia zaawansowania raka tarczycy rozpoznanego przedoperacyjnie i przypadkowo po operacji wola nienowotworowego.

INTRODUCTION: The aim of this study was to compare staging of incidentally diagnosed thyroid cancer (TC) to staging of preoperatively suspected TC. METHODS: This was a retrospective study of 224 patients who underwent surgery for primary TC between 2009 and 2011. Clinical and pathological data included in the TNM and AJCC staging system (7th edition, 2010) were analysed. Staging of incidentally diagnosed TC was compared to staging of preoperatively suspected TC. RESULTS: Suspicion of TC was made before surgery in 57.6% patients, and in 42.4% patients TC was diagnosed postoperatively. Papillary TC was predominant and followed by follicular TC, which were suspected in 88.4% and 4.7% of patients before surgery, and were diagnosed in 77.9% and 16.8% of patients postoperatively (p=0.035 and p<0.001, respectively). Preoperatively diagnosed TC was predominant in patients below 45 years of age (64.3% vs. 25.3%; p<0.001), was at lower stage at the diagnosis (according to AJCC in stage I : 42.6% vs. 67.4%; p<0.001; in stage II: 6.2% vs. 12.6%; p=0.095; in stage III: 38.0% vs. 16.8%; p<0.001; in stage IV: 13.2% vs. 3.2%; p=0.009, respectively), and it was more common multicentric (29.5% vs. 9.5%; p<0.001) than incidental TC. CONCLUSIONS: Approximately 40% of cases of TC is diagnosed incidentally based on postoperative pathology report. Incidental TC is predominant below age 45 years, is revealed with early-stage more common than TC diagnosed preoperatively, and occurs multicentric less frequently.

Coexistence of papillary thyroid cancer with Hashimoto thyroiditis.

AIMS: Conflicting data have been reported with regard to Hashimoto thyroiditis (HT) and risk of malignancy. The aim of this study was to evaluate coexistence of papillary thyroid cancer (PTC) with HT. PATIENTS AND METHODS: This is a retrospective cohort study in which HT was diagnosed in 452 (F/M ratio = 405:47, median age 53.5 ± 12.1 years) of 7,545 patients qualified for thyroidectomy throughout the years 2002 to 2010. Pathological reports were reviewed to identify prevalence of PTC in HT vs. non-HT patients. RESULTS: PTC was diagnosed in 106 of 452 (23.5 %) HT patients vs. 530 of 7,093 (7.5 %) non-HT patients (p < 0.001). Metastases to level VI lymph nodes were observed in 81 of 106 (76.4 %) patients with PTC in HT vs. 121 of 530 (22.8 %) patients with PTC in non-HT disease (p < 0.001). CONCLUSIONS: HT was associated with a threefold increase of PTC prevalence as compared to other non-HT thyroid diseases, and the spread of PTC to level VI lymph nodes was four times more frequent in HT than in non-HT patients.

Minimally invasive video-assisted thyroidectomy: seven-year experience with 240 cases.

INTRODUCTION: Minimally invasive video-assisted thyroidectomy (MIVAT) has gained acceptance in recent years as an alternative to conventional thyroid surgery. AIM: Assessment of our 7-year experience with MIVAT. MATERIAL AND METHODS: A retrospective study of 240 consecutive patients who underwent MIVAT at our institution between 01/2004 and 05/2011 was conducted. The inclusion criterion was a single thyroid nodule below 30 mm in diameter within the thyroid of 25 ml or less in volume. The exclusion criteria were previous thyroid or parathyroid surgery, T2 or higher thyroid cancer, N1 stage, and thyroiditis. The Miccoli technique was used. The analysis included indications, eligibility rate, operative time, morbidity and cosmetic effects. RESULTS: Of 6,574 patients referred for thyroid surgery, 240 (3.6%) were eligible for MIVAT. In the final pathology report, there were 206 follicular adenomas, 21 papillary thyroid cancers, 9 cases of Graves' disease and 4 follicular cancers. Reasons for exclusion were as follows: thyroid volume above 25 ml in 5401 (85.3%), thyroid cancer larger than stage T1 in 392 (6.2%), thyroiditis in 358 (5.6%), and previous neck surgery in 183 patients (2.9%). Minimally invasive video-assisted thyroidectomy operations consisted of 210 lobectomies and 30 total thyroidectomies, including 15 one-stage parathyroidectomies. Mean operative time was 38.6 ±15.1 min. Transient versus permanent recurrent laryngeal nerve injury was found in 8 (3.0%) vs. 2 (0.7%) nerves at risk, respectively. Cosmetic effects were assessed after 1 and 6 months of follow-up as very good or excellent by 89.6% and 95.8% of patients, respectively. CONCLUSIONS: Minimally invasive video-assisted thyroidectomy is suitable for surgeons experienced in thyroid and video-assisted surgery. It is feasible for well-selected patients including cases of T1 thyroid cancer, Graves' disease and concomitant parathyroid adenoma.

Randomized controlled trial of visualization versus neuromonitoring of the external branch of the superior laryngeal nerve during thyroidectomy.

BACKGROUND: Injury to the external branch of the superior laryngeal nerve (EBSLN) during thyroidectomy results in a lowered fundamental frequency of the voice and deteriorated voice performance in producing high-frequency sounds. It remains unclear if the use of intraoperative nerve monitoring (IONM) can improve the clinical outcome of thyroidectomy in terms of preserved individual voice performance. This study was designed to test that hypothesis. METHODS: A total of 210 consenting female patients planned for total thyroidectomy were randomly assigned to two groups equal in size (n = 105): visual inspection of the EBSLN and RLN vs. this plus additional EBSLN and RLN monitoring. The primary outcome was the identification rate of the EBSLN. The secondary outcomes included: anatomical variability of the EBSLN according to the Cernea classification and changes in postoperative voice performance. Voice assessment included pre- and postoperative videostrobolaryngoscopy and an analysis of maximum phonation time (MPT), voice level (VL), fundamental frequency (Fo), and voice quality rating on the GRBAS scale. RESULTS: The following differences were found for operations without vs. with IONM: identification rate of the EBSLN was 34.3 % vs. 83.8 % (p < 0.001), whereas a 10 % or higher decrease in phonation parameters was found in 10 % vs. 2 % patients for MPT (p = 0.018), 13 % vs. 2 % for VL (p = 0.003), and 9 % vs. 1 % for Fo (p = 0.03), a change in the GRBAS scale > 4 points in 7 % vs. 1 % (p = 0.03), and temporary RLN injury was found in 2 % vs. 1 % (p = 0.56), respectively. CONCLUSIONS: The use of IONM significantly improved the identification rate of the EBSLN during thyroidectomy, as well as reduced the risk of early phonation changes after thyroidectomy.

Total thyroidectomy for non-toxic multinodular goiter with versus without the use of harmonic FOCUS dissecting shears - a prospective randomized study.

INTRODUCTION: Thyroidectomy is among the most commonly performed procedures involving the endocrine glands and the development of advanced surgical methods combined with a strife for performing the operation in a manner that is minimally invasive for the patient has considerably increased the need for instruments that would limit surgical trauma. AIM: To compare of the outcomes of total thyroidectomy operations with and without the use of ultrasonic harmonic FOCUS dissecting shears. MATERIAL AND METHODS: Eighty-two patients with a bilateral, non-toxic multinodular goiter were randomized to two groups of 41 patients each. Total thyroidectomy was performed in each patient. In the clip-ligation group (CL-G), during thyroidectomy, the superior thyroid vessels were clipped and bipolar coagulation was used to secure smaller vessels, whereas in the harmonic FOCUS group (HF-G), a harmonic device was used to dissect and divide all the thyroid vessels. The statistical analysis included the mean operative time, blood loss, postoperative morbidity and cost-effectiveness. RESULTS: HF-G vs. CL-G operations were shorter (45.4 ±8.7 min vs. 64.5 ±14.2 min; p < 0.001), characterized by a lower mean blood loss (29.9 ±9.8 ml vs. 56.8 ±11.0 ml; p < 0.001) and appeared to be more cost-effective (666.2 ±37.5 EUR vs. 718.0 ±69.2 EUR; p < 0.01). No major complications were observed in both groups. CONCLUSIONS: In total thyroidectomy operations, the harmonic FOCUS is safe and facilitates dissection, allowing for a significant decrease in operative time. Other benefits include lower blood loss and a slightly decreased cost of the procedure.

Clinical value of intraoperative neuromonitoring of the recurrent laryngeal nerves in improving outcomes of surgery for well-differentiated thyroid cancer.

UNLABELLED: The recurrent laryngeal nerve (RLN) is particularly prone to injury during thyroidectomy in case of extralaryngeal bifurcation being present in approximately one-third of patients near the inferior thyroid artery or ligament of Berry. Meticulous surgical dissection in this area may be additionally facilitated by the use of intraoperative neuromonitoring (IONM) to assure safe and complete removal of thyroid tissue. The aim of the study was to verify the hypothesis that meticulous surgical technique of tissue dissection in the area of the posterior surface of the thyroid capsule and adjacent RLN may be additionally facilitated by intraoperative neuromonitoring (IONM), and may contribute to increasing the safety and radicalness of total thyroidectomy in patients with well-differentiated thyroid cancer. MATERIAL AND METHODS: The outcomes of total thyroidectomy with level VI lymph node clearance for well-differentiated thyroid cancer (WDTC; pT1-3, N0-1, Mx) were retrospectively compared between 151 patients undergoing surgery with IONM (01/2005-06/2009) and 151 patients undergoing surgery without IONM (2003-2004). RLN morbidity (calculated for nerves at risk) was assessed by videolaryngoscopy or indirect laryngoscopy (mandatory before and after surgery and at 12-month follow-up). The anatomical course of the extralaryngeal segment of RLNs were analyzed in detail in each operation. Thyroid iodine uptake (131I) was measured during endogenous TSH stimulation test a week before radioiodine therapy. RESULTS: Among patients operated with vs. without IONM, the early RLN injury rate was 3% vs. 6.7% (p=0.02), including 2% vs. 5% (p=0.04) of temporary nerve lesions, and 1% vs. 1.7% of permanent nerve events (p=0.31), respectively. Extralaryngeal RLN bifurcation was identified in 42 (27.8%) vs. 25 (16.6%) of patients operated with vs. without IONM, respectively (p=0.001). Mean I-131 uptake following total thyroidectomy with vs. without IONM was 0.67 ± 0.39% vs. 1.59 ± 0.69% (p<0.001). 131I uptake lower than 1% was found in 106 (70.2%) vs. 38 (25.2%) patients operated with vs. without IONM, respectively (p<0.001). CONCLUSIONS: Most patients with WDTC who undergo total thyroidectomy have a small amount of residual thyroid tissue. The use of IONM may improve the outcomes of surgery among these patients by both increasing the completeness of total thyroidectomy and significantly reducing the prevalence of temporary RLN injury. The possible mechanism of this improvement is the aid in dissection at the level of the Berry's ligament offered by IONM which enhances the surgeon's ability to identify a branched RLN, and allows for reduction of traction injury and neuropraxia of the anterior branch of bifid nerves.

Total thyroidectomy for benign thyroid disease: is it really worthwhile?

OBJECTIVE: To compare the outcomes of bilateral subtotal (BST) versus total thyroidectomy (TT) for benign bilateral thyroid disease (BBTD). BACKGROUND: The extent of thyroid resection in benign goiter is controversial. Potential advantages of TT over BST may include: one-stage removal of incidental thyroid cancer, and a lower risk for goiter recurrence. However, these potential advantages should outweigh the risk of morbidity. METHODS: A retrospective cohort study was conducted of 8032 patients with BBTD operated in a single institution. Patients in Group A underwent BST (1999-2004, n = 5214; follow-up 72.3 ± 12.4 months), whereas patients in Group B underwent TT (2005-2009, n = 2918; follow-up 36.3 ± 10.6 months). Data were collected prospectively. The analysis included: prevalence of incidental thyroid cancer, recurrent goiter, need for completion thyroidectomy, and morbidity. RESULTS: Incidental thyroid cancer was found in 406 (5.00%) patients. One hundred twelve (2.15%) BST versus 3 (0.10%) TT patients required completion thyroidectomy (P < 0.001). Recurrent goiter was diagnosed in 364 (6.99%) BST patients and 165 (45.33%) required reoperation versus 0% after TT (P < 0.001). The prevalence of transient and permanent hypoparathyroidism was 2.70% and 0.15% versus 13.12% and 0.10% (BST vs. TT, P < 0.001 and P = 0.65, respectively). The prevalence of temporary and permanent RLN injury was 2.30% and 0.71% versus 2.60% versus 0.69% (BST vs. TT, respectively; nonsignificant). CONCLUSIONS: Compared to TT, BST resulted in a significantly higher rate of completion thyroidectomy for incidentally diagnosed thyroid cancer and need for redo surgery for recurrent goiter. The extent of surgical resection had no significant impact on the prevalence of permanent complications. REGISTRATION NUMBER: NCT01273714 (http://www.clinicaltrials.gov).

[Prevalence of metastatic lymph nodes in the central compartment of the neck following prophylactic clearance for papillary thyroid cancer]. / Ocena czestosci przerzutów raka brodawkowatego tarczycy do wezlów chlonnych kompartmentu centralnego szyi u chorych poddawanych profilaktycznej limfadenektomii.

INTRODUCTION: Clinical suspicion of regional lymph nodes' involvement is present in approximately 10% of patients with papillary thyroid cancer (PTC). Nevertheless, among the remaining 90% of individuals staged pre-, or intraoperatively as node negative, some cases of metastatic lymph nodes from PTC are found on final pathological report. Both quality of life and survival can be influence by eventual nodal recurrence in this group of patients. AIMS: To evaluate the prevalence of metastatic lymph nodes in patients with PTC in stage cT1-3NxMx undergoing prophylactic central compartment lymph nodes' clearance, and to assess associated morbidity. METHODS: Clinical database of patients with thyroid cancer undergoing surgery in 2009 and 2010 was retrospectively analyzed. 116 (78.9%) patients with PTC, with pre-, or intraoperatively not suspected lymph nodes were identified. Total extracapsular thyroidectomy with one-stage prophylactic bilateral level VI lymph nodes clearance was performed in all patients. The numbers of excised and metastatic lymph nodes within the surgical specimen were analyzed. In addition, surgical morbidity was evaluated. RESULTS: Metastatic level VI lymph nodes' involvement was found in 22 of 116 (19%) patients. Mean number of lymph nodes within the surgical specimen was 4.5 +/- 3.3 (1-17, median 4). Mean number of 1 +/- 2 metastatic lymph nodes were identified (0-7, median 1). Transient vs. permanent hypoparathyroidism was found in 31 (26.7%) vs. 2 (1.7%) and temporary vs. permanent recurrent laryngeal nerve injury was found in 7 (3.0%) vs. 2 (0.9%) of 232 nerves at risk. CONCLUSIONS: One fifth of PTC patients with clinically and intraoperatively non-suspected lymph nodes within the central compartment are positive for metastatic nodal de- posits in surgical specimen following prophylactic level VI clearance.