Safety and feasibility of single-port surgery for posterior retroperitoneal adrenalectomy using the da Vinci SP robotic system: a retrospective cohort study.

BACKGROUND: This study demonstrates our experience of single-port robotic posterior retroperitoneal adrenalectomy (RPRA) using the da Vinci SP robot system and evaluates its technical feasibility and surgical outcomes. METHODS: We conducted a retrospective analysis of 250 RPRAs, including 117 conventional 3-port RPRAs, 103 reduced 2-port RPRAs, and 30 single-port RPRAs. Each RPRA type was compared by analyzing 30 patients in the early phase of surgery. RESULTS: All patients who underwent single-port RPRA showed excellent surgical outcomes. Age, sex, BMI, and tumor location site did not significantly differ between the three groups. In the early phase, the size of the adrenal tumor was similar between three groups, and it tended to increase as the number of ports increased (p < 0.001). The mean operation time was shorter for patients who underwent single-port RPRA than those who underwent RPRA types (p < 0.001). The numeric rating scale score did not significantly differ between the groups on most days. No major complications were observed, and no patients were converted to open surgery or required additional port insertion. CONCLUSION: Single-port RPA using the da Vinci SP robotic system showed the effectiveness of the surgical procedure and improved cosmetic outcomes for patients, while also enabling surgeons to perform operations with greater ease and convenience. Therefore, single-port RPRA could be a good alternative option for the treatment of adrenal tumors in selected situations.

Prognosis of Patients with 1-4 cm Papillary Thyroid Cancer Who Underwent Lobectomy: Focus on Gross Extrathyroidal Extension Invading Only the Strap Muscles.

BACKGROUND: This study was designed to evaluate the prognostic implication of gross extrathyroidal extension (ETE) invading the strap muscles after thyroid lobectomy in patients with 1-4 cm papillary thyroid cancer (PTC). METHODS: This retrospective cohort study included patients with 1-4 cm PTC who underwent thyroid lobectomy from 2005 to 2012. Overall, 595 patients were enrolled after excluding patients with aggressive variants of PTC, gross ETE into a major neck structure, and lateral cervical lymph node (LN) metastasis. We evaluated the risk factors for structural recurrence after lobectomy in 1-4 cm PTC. RESULTS: Seventy-eight patients (13.1%) had gross ETE invading only the strap muscles. During the median follow-up period of 7.7 years, structural recurrence was confirmed in 35 patients (5.9%). The presence of gross ETE was an independent risk factor for structural recurrence (hazard ratio 2.54, 95% confidence interval 1.19-5.44; p = 0.016). Subgroup analysis of patients with gross ETE showed that 11 and 47 patients had low- and intermediate-risk LN metastasis, respectively. A significant difference in recurrence-free survival was observed according to the degree of cervical LN metastasis (p = 0.03). Those without LN metastasis or low-risk LNs had a 75% lower risk of recurrence when compared with those with both gross ETE and intermediate-risk LNs. CONCLUSION: Gross ETE and intermediate-risk cervical LN metastasis were associated with a significantly high risk of recurrence after lobectomy in patients with 1-4 cm PTC. Completion thyroidectomy would be considered in this subgroup of patients but not in all patients with gross ETE invading only the strap muscles.

The association between the type of anesthesia and hemodynamic instability during pheochromocytoma surgery: a retrospective cohort study.

BACKGROUND: Pheochromocytoma often carries a risk for perioperative hemodynamic instability (HDI). The aim of this study is to evaluate the risk factors of intraoperative HDI during minimally invasive posterior retroperitoneal adrenalectomy (PRA) for pheochromocytoma. MATERIALS AND METHODS: This retrospective study analyzed the prospectively collected data of 172 patients who underwent laparoscopic PRA or robotic PRA for pheochromocytoma between January 2014 and December 2020 at a single tertiary center. The patients were divided into two groups according to the intraoperative hypertensive event of systolic blood pressure (> 160 mmHg). The clinical manifestations and perioperative hemodynamic conditions were analysed. RESULTS: In the multivariate logistic regression analysis, the tumor size (> 3.4 cm) [OR 3.14, 95% confidence intervals (CI) (1.48-6.64), p = 0.003], type of preoperative alpha-blocker (selective type) [OR 3.9, 95% CI (1.52-10.02), p = 0.005], preoperative use of beta-blockers [OR 3.94, 95% CI (1.07-14.49), p = 0.039] and type of anesthesia [total intravenous anesthesia (TIVA) vs. balanced anesthesia (BA)] [OR 2.57, 95% CI (1.23-5.38), p = 0.012] were determined as independent risk factors of intraoperative hypertensive events during minimally invasive adrenalectomy. CONCLUSIONS: The type of anesthesia was independently associated with intraoperative HDI along with larger tumor size, type of preoperative alpha-blocker and the use of preoperative beta-blockers. TIVA increased the risk of intraoperative hypertensive events compared with BA. Thus, the consideration of the type of anesthesia prior to adrenal surgery for pheochromocytoma along with the use of preoperative non-selective alpha-blockers may be beneficial in minimizing the risk of intraoperative HDI.

Thyroid-dedicated internally-cooled wet electrode for benign thyroid nodules: experimental and clinical study.

BACKGROUND: To assess the effects of radiofrequency ablation (RFA) using an internally-cooled wet (ICW) electrode in ex vivo bovine liver and evaluate the feasibility of the ICW electrode for benign thyroid nodules. METHODS: We developed an 18-gauge ICW electrode with a microhole at the distal tip for tissue infusion of chilled (0 - 4 °C) isotonic saline (rate = 1.5 ml/min). RFA using ICW and IC electrodes were performed in bovine livers (40 pairs, 1-cm active tip, 50 W, 1-min). We compared the morphological characteristics of ablation zones and presence of carbonization. Twenty patients with benign thyroid nodules larger than 5 ml were prospectively enrolled in a clinical study and underwent ultrasound-guided RFA with ICW electrodes. Ultrasound examinations, laboratory data, and symptom and cosmetic scores were evaluated preprocedure and 1 and 6 months after the procedure. RESULTS: In the ex vivo study, the ICW achieved significantly larger ablation zones than the IC (p<.001). In the clinical study, ICW electrodes were tolerable in all patients. At last follow-up, nodule volume had decreased from 15.6 ± 12.1 ml to 4.1 ± 4.3 ml (p<.001), and the mean volume reduction ratio (VRR) was 73.3 ± 13.7% at 6.0 months follow-up. Cosmetic and symptom scores were reduced from 3.52 ± 1.03 to 2.65 ± 0.88 and 3.10 ± 2.17 to 0.85 ± 0.99 (both p<.001), respectively. After RFA, thyroid function was well preserved in all patients, and mean thyroglobulin level decreased from 36.6 ± 52.1 ng/ml to 26.9 ± 62.2 ng/ml. One patient experienced a temporary voice change that recovered within a week. CONCLUSIONS: We developed a thyroid-dedicated ICW electrode that we showed to be feasible and effective in patients with benign thyroid nodules.

Comparison Between Familial and Sporadic Non-medullary Thyroid Carcinoma: A Retrospective Individual Risk Factor-Matched Cohort Study.

BACKGROUND: This study aimed to compare clinicopathologic features and outcomes between patients with familial non-medullary thyroid carcinoma (FNMTC) and patients with sporadic non-medullary thyroid carcinoma (SNMTC) after performing individual risk factor-matching. Additionally, the study evaluated a dynamic risk stratification (DRS) system to validate its usefulness for familial-type thyroid carcinoma. METHODS: After individual risk factor-matching, 286 patients remained in the FNMTC group, and 858 patients were assigned to the SNMTC group consisting of papillary thyroid carcinoma (PTC). The prognostic outcomes were compared between the two groups in a matched cohort. RESULTS: During the mean follow-up period of 142 months, recurrences were experienced by 64 patients in the sporadic group (7.5%) and 29 patients in the familial group (10.1%). In the multivariate analysis, the independent risk factors for recurrence were primary tumor size (p = 0.033), gross extrathyroidal extension (p = 0.001), and lymph node metastasis (p < 0.001). The independent risk factors did not include family history alone (p = 1.101) or the number of affected family members (p = 0.122 for 2 members and p = 0.625 for ≥ 3 members). In this matched-cohort study, the DRS system was well adjusted in the FNMTC and SNMTC groups. Moreover, the proportion of DRS categories and the recurrence rate in each DRS category were similar between the familial and sporadic groups. CONCLUSIONS: Family history did not present a statistically significant association with a poor prognosis for PTC patients. With a family history of PTC alone, less aggressive treatment could be considered. In this matched cohort, DRS was adjusted well and could be useful in predicting prognosis, even for PTC patients with a family history of PTC.

Clinical implications of age and excellent response to therapy in patients with high-risk differentiated thyroid carcinoma.

BACKGROUND: Patients with American Thyroid Association (ATA) high-risk differentiated thyroid carcinoma (DTC) have poor clinical outcomes. This study aimed to evaluate the clinical implications of age and response to therapy classification in patients with ATA high-risk DTC. DESIGN AND PATIENTS: This study included 222 patients with high-risk DTC who initially underwent therapy between 2000 and 2010 in a single tertiary center in Korea. We evaluated the prognostic parameters associated with progression-free survival (PFS) and disease-specific survival (DSS) with a focus on age and achieving an excellent response (ER). RESULTS: During the median follow-up period of 11.3 years, disease progression was detected in 77 patients (34.7%), and disease-specific mortality was reported in 31 patients (14.0%). Older age (≥55 years) and not achieving ER (not-ER) were independent risk factors associated with PFS (age, p < .001; not-ER, p < .001) and DSS (age, p < .001; not-ER, p = .015). Of the 74 patients in the ER group, 7 (9.5%) displayed disease progression and 1 (1.4%) died from DTC. There were no significant differences in PFS and DSS according to age in the ER group. However, older patients had significantly worse PFS and DSS than younger patients in the not-ER group (p = .002 and p < .001, respectively). CONCLUSIONS: Response to therapy classification is important for predicting PFS and DSS in patients with high-risk DTC. Patients in the ER group had a relatively good prognosis, but disease progression occurred in 9.5% of patients. Age was a key predictor of both PFS and DSS in high-risk patients who did not achieve ER.

Modified risk stratification based on cervical lymph node metastases following lobectomy for papillary thyroid carcinoma.

OBJECTIVE: Evidence for American Thyroid Association (ATA) risk stratification stems largely from studies involving patients undergoing total thyroidectomy. We aimed to assess the risk of recurrence according to the present ATA risk stratification system in patients who underwent lobectomy. DESIGN: Retrospective cohort study. PATIENTS: Patients who underwent thyroid lobectomy for 1-4 cm-sized papillary thyroid carcinoma (n = 571). MEASUREMENTS: Disease-free survival (DFS) was compared according to the ATA risk stratification, and specific lymph node (LN) characteristics were evaluated to modify the ATA criteria with a higher predictability for recurrence. RESULTS: Based on the ATA risk stratification, 439 patients (61.1%) were classified into intermediate- or high-risk group, and consideration for completion thyroidectomy is suggested by ATA guidelines for these patients. However, no significant differences were found in DFS among the low-, intermediate- and high-risk groups (P = .9). In contrast, when patients were stratified according solely to the LN criteria from the ATA risk stratification, only 127 patients (22.2%) had intermediate risk (intermediate-N1a) and exhibited significantly poorer DFS than those with N0 disease (P = .035). Modifying the intermediate-N1a criteria by adding the extranodal extension (ENE) status and omitting the clinical nodal disease enabled the subclassification of 19 patients (3%) with a high risk for recurrence. CONCLUSIONS: The present study suggests that risk stratification based solely on LN metastases is more reasonable for predicting structural persistence/recurrence following lobectomy than that based on the overall ATA criteria. Considering the ENE status can assist in selecting patients with a high risk of recurrence to minimize further treatments.

Safety and feasibility of reduced-port site surgery for robotic posterior retroperitoneal adrenalectomy.

BACKGROUND: Minimally invasive surgery, such as laparoscopic adrenalectomy and robotic adrenalectomy, has become a treatment of choice for benign adrenal tumors. Efforts are ongoing to minimize the invasiveness of the procedure and to reduce the number of port sites. The primary endpoint of this study was the safety and feasibility of a reduced-port site technique for robotic posterior retroperitoneal adrenalectomy (RPRA). METHODS: This study retrospectively analyzed 74 RPRAs performed by a single surgeon, including 30 conventional three-port site early-phase RPRAs, 30 three-port site late-phase RPRAs, and 14 reduced-port site RPRAs. Reduced-port site RRPA was defined as using two port sites: one for a multi-glove port and one for an additional side port. The clinicopathological features and surgical outcomes were compared in these three groups. RESULTS: No major complications were observed following RPRA in the three groups of patients. Operation time, pain score, and hospital stay did not differ significantly among these three groups. CONCLUSIONS: RPRA using a reduced-port site system was safe and feasible and may be a good alternative to conventional three-port site RPRA for benign adrenal tumors in certain situations.

Usefulness of a 3D-Printed Thyroid Cancer Phantom for Clinician to Patient Communication.

BACKGROUND: Thyroid glands and surrounding structures are very complex, and this complexity can pose a challenge for clinicians when explaining and communicating to the patient the details of a proposed surgery for thyroid cancer. A three-dimensional (3D) thyroid cancer model could help and improve this communication. METHODS: A 3D-printed phantom of a thyroid gland and its presenting cancer was produced from segmented head and neck contrast-enhanced computed tomography (CT) data from a patient with thyroid cancer. The phantom reflects the complex anatomy of the arteries, veins, nerves, and other surrounding organs, and the printing materials and techniques were adjusted to represent the texture and color of the actual structures. Using this phantom, patients and clinicians completed surveys on the usefulness of this 3D-printed thyroid cancer phantom. PARTICIPANTS: patients (n = 33) and clinicians (n = 10). RESULTS: In the patient survey, the patients communicated that the quality of understanding of their thyroid disease status was enhanced when clinicians explained using the phantom. The clinicians communicated that the 3D phantom was advantageous for explaining complex thyroid surgery procedures to patients, and that the 3D phantom was helpful in educating patients with relatively poor anatomical knowledge. CONCLUSIONS: Using 3D printing technology, we produced a CT-based 3D thyroid cancer phantom, and patient and clinician surveys on its utility indicated that it successfully helped educate patients, providing them with an improved understanding of the disease.

The value of preoperative antithyroidperoxidase antibody as a novel predictor of recurrence in papillary thyroid carcinoma.

The link between chronic lymphocytic thyroiditis (CLT) and papillary thyroid carcinoma (PTC) is widely recognized. Considering the strong association between raised antithyroidperoxidase antibody (TPOAb) and CLT, we postulated that the preoperative TPOAb can predict the prognosis of PTC, particularly for recurrence. A total of 2,070 patients who underwent total thyroidectomy for classical type PTC with tumor size ≥1 cm and with available data on preoperative TPOAb and TgAb were enrolled to compare disease-free survival (DFS) according to the presence of preoperative TPOAb, TgAb, and coexistent CLT. Patients with positive preoperative TPOAb had a significantly better DFS compared to patients without positive preoperative TPOAb (hazard ratio (HR) 0.53; 95% confidence interval (CI) 0.30-0.94, p = 0.028) while no difference in DFS was found according to preoperative TgAb status. Positive preoperative TPOAb was an independent prognostic factor for structural persistent/recurrent disease after adjustment for major preoperative risk factors such as age, sex, and tumor size (HR 0.52, 95% CI 0.28-0.99, p = 0.048). Although the coexistence of CLT lowered the risk for structural persistence/recurrence in univariate analysis (HR 0.52, 95% CI 0.31-0.86, p = 0.012), it was not an independent favorable prognostic factor by multivariate analysis (HR 0.65, 95% CI 0.38-1.10, p = 0.106). However, when coexistent CLT was combined with positive preoperative TPOAb, it indicated an independent protective role in structural persistent/recurrent disease (HR 0.39, 95% CI 0.16-0.98, p = 0.045). Our study clearly showed that presence of preoperative TPOAb can be a novel prognostic factor in predicting structural persistence/recurrence of PTC.

Clinical Significance of Gross Invasion of Strap Muscles in Patients With 1- to 4-cm-Sized Papillary Thyroid Carcinoma Undergoing Lobectomy.

BACKGROUND: Given the emerging evidence supporting the lack of prognostic significance of gross extrathyroidal extension invading only strap muscles (strap-gETE), this study investigated whether lobectomy is feasible for patients with strap-gETE. METHODS: A retrospective cohort study was conducted with 636 patients who had 1- to 4-cm-sized papillary thyroid carcinoma (PTC) treated with thyroid lobectomy. Patients with gross invasion of perithyroidal organs other than strap muscles or synchronous distant metastasis were excluded from the study. Disease-free survival (DFS) was compared according to the presence of strap-gETE. RESULTS: Strap-gETE was present in 50 patients (7.9%), with the remaining 586 patients (92.1%) showing no evidence of gETE. During the median follow-up period of 7.4 years, 6% of the patients with strap-gETE and 5.1% of the patients without gETE experienced structural persistent/recurrent disease (p = 0.99). No differences in DFS were observed between the two groups (hazard ratio [HR], 1.24; 95% confidence interval [CI], 0.38-4.08; p = 0.720). After adjustment for five major risk factors (age, gender, tumor size, multifocality, and cervical lymph node metastasis status) in the multivariate analysis, the presence of strap-gETE did not exhibit an independent role in the development of structural persistent/recurrent disease (HR 1.05; 95% CI 0.24-4.53, p = 0.950). CONCLUSIONS: Strap-gETE did not increase the risk of structural persistent/recurrent disease for the patients who underwent lobectomy for 1- to 4-cm-sized PTC. The study data support the limited role of strap-gETE in clinical outcomes and may broaden the indications for lobectomy for patients with PTCs.

Is Male Gender a Prognostic Factor for Papillary Thyroid Microcarcinoma?

BACKGROUND: Male gender is a prognostic factor of poor outcome in papillary thyroid carcinoma (PTC). We investigated the prognostic role of male gender in papillary thyroid microcarcinoma (PTMC). METHODS: We included 2930 patients who underwent surgery at Asan Medical Center for PTC. Clinicopathologic characteristics from the patients' medical records were compared for male and female PTC patients. Independent prognostic factors for recurrence in PTC and PTMC were evaluated after propensity score matching analysis. The median follow-up period was 82 months. RESULTS: Recurrence and death were more common in male patients with PTC than in female patients with PTC (12.6 vs. 9.6%, p = 0.03 and 2.2 vs. 0.6%, p < 0.001, respectively). However, there was no difference in disease-free survival between male and female PTMC patients (p = 0.57). Multivariate analysis after propensity score matching revealed that male gender is not an independent prognostic factor of recurrence in PTMC (hazard ratio [HR] 1.5, 95% confidence interval 0.75-5.33, p = 0.17), but that it is an independent prognostic factor in PTC >1 cm (HR = 3.06, 95% confidence interval 1.34-6.98, p = 0.008). CONCLUSIONS: Male gender is an independent prognostic factor for recurrence in PTC >1 cm, but it is not a prognostic factor in PTMC.

Prognostic Impact of Further Treatments on Distant Metastasis in Patients With Minimally Invasive Follicular Thyroid Carcinoma: Verification Using Inverse Probability of Treatment Weighting.

BACKGROUND: The aim of this study was to evaluate the prognostic impact of further treatments in minimally invasive follicular thyroid carcinoma (MIFTC) patients. METHODS: The risk factors for distant metastases were analyzed, and the impact of surgical extent on distant metastasis was verified by using weighted logistic regression models with inverse-probability of treatment weighting (IPTW). RESULTS: 166 patients including 31 males (18.7 %) and 135 females (81.3 %), with the mean age of 41.5 ± 13.5 years, were enrolled for this study. The median follow-up period was 103.5 months (range, 13-244 months). Seven patients (4.2 %) had distant metastases during follow-up period. The presence of vascular invasion (Hazard ratio [HR] = 29.06; 95 % Confidence Interval [CI] = 3.06-209.08; p = 0.015) and extensive vascular invasion ≥4 foci (HR = 40.57; 95 % CI = 2.09-789.13; p = 0.014) were the independent risk factors for distant metastasis by multivariate analysis. Surgical extent did not influence distant metastasis. Logistic regression with IPTW also demonstrated that there were no statistically significant differences in the development of distant metastasis based on surgical extent (HR = 1.28; 95 % CI = 0.15-10.87; p = 0.823). CONCLUSIONS: The presence of extensive vascular invasion is the most powerful predictor of distant metastasis. However, it is noteworthy that further treatments do not demonstrate an advantageous effect on preventing distant metastasis during the follow-up period.

Ultrasonography features of medullary thyroid cancer as predictors of its biological behavior.

Background Although there are many well-known prognostic predictors of medullary thyroid carcinoma (MTC), the ultrasonography (US) findings of MTC have not been sufficiently validated in this regard. Purpose To investigate the US findings of MTC and their relationship with the biological behavior of MTC. Material and Methods The US findings and clinical and pathology records of 123 MTC nodules from 108 patients were retrospectively analyzed at two tertiary referral hospitals. MTCs were classified according to US findings, i.e. MTC with benign (B-MTC) and malignant US findings (M-MTC). We then compared the clinical and pathology findings between the two groups. Results Eighty-two M-MTCs (66.7%) and 41 B-MTCs (33.3%) were identified. M-MTCs showed a significantly higher prevalence of lateral lymph node metastases as well as extrathyroidal and extranodal extension (all P < 0.05). M-MTCs larger than 1 cm showed a significantly higher prevalence of multifocality, recurrence, extrathyroidal and extranodal extension than B-MTCs larger than 1 cm in the largest dimension (all P < 0.05). Tumors > 1 cm were more likely to be B-MTC and one-third of all MTCs had benign US features. The common findings of B-MTC included a solid, ovoid to round shape, with a smooth margin, hypoechogenicity, and without calcification. Conclusion The biological behavior of M-MTCs results in poorer outcomes than that of B-MTCs.

Initial clinical experience with BRAF(V600E) mutation analysis of core-needle biopsy specimens from thyroid nodules.

OBJECTIVE: The accurate diagnosis of thyroid nodules is important for making management decisions. The purpose of this study was to evaluate the feasibility of core-needle biopsy with BRAF(V600E) mutation analysis (CNB + BRAF(V600E) ) and to compare the clinical usefulness of CNB + BRAF(V600E) and fine-needle aspiration with BRAF(V600E) mutation analysis (FNA + BRAF(V600E) ) in the diagnosis of thyroid malignancy. DESIGN, PATIENTS AND MEASUREMENTS: The results of BRAF(V600E) mutation analyses of 820 nodules from 820 patients (153 men, 667 women; mean age, 51·1 years), who underwent CNB + BRAF(V600E) (n = 256) or FNA + BRAF(V600E) (n = 564) between January 2011 and March 2012 were retrospectively evaluated. The feasibility of CNB + BRAF(V600E) was assessed by comparing its rate of detection of BRAF(V600E) mutations and positive predictive value with those of FNA + BRAF(V600E) . The clinical usefulness of CNB + BRAF(V600E) was determined by comparing rates of inconclusive results, the additional value of BRAF(V600E) mutation analysis, diagnostic surgery and diagnostic performance with those of FNA + BRAF(V600E) . RESULTS: CNB + BRAF(V600E) and FNA + BRAF(V600E) had similar rates of BRAF(V600E) mutation detection (66·3% vs 64·4%, P = 0·883) and positive predictive value (100·0% vs 96·6%, P = 0·135). CNB + BRAF(V600E) had a significantly higher diagnostic accuracy rate (95·7% vs 85·9%, P < 0·001), and significantly lower rates of inconclusive results (8·2% vs 51·8%, P < 0·001), and diagnostic surgery (8·9% vs 22·3%, P = 0·006), than FNA + BRAF(V600E) . CONCLUSIONS: The greater diagnostic performance of CNB + BRAF(V600E) and its lower rate of inconclusive results than FNA + BRAF(V600E) suggest that CNB + BRAF(V600E) can reduce rates of preventable diagnostic surgery.

Changing trends in the clinicopathological features and clinical outcomes of medullary thyroid carcinoma.

BACKGROUND: The early detection of papillary thyroid cancer has contributed to the increase in the incidence and improved clinical outcomes. However, recent changes of medullary thyroid carcinoma (MTC) over time remain unclear. We evaluated changes of the clinicopathological characteristics and clinical outcomes in patients with MTC in recent years. METHODS: A total of 109 MTC patients were classified based on the year of initial surgery: 1996-2000 (n = 14), 2001-2006 (n = 39), and 2007-2011 (n = 56). RESULTS: The primary tumor size significantly decreased and the proportion of microMTCs (size ≤1 cm) increased over time (P = 0.002 and P < 0.001, respectively). The proportion of patients with cervical lymph node (LN) metastasis significantly decreased (P = 0.037), and the ratio of metastatic LNs significantly decreased (P = 0.011). Disease-free survival (DFS) rate of patients was significantly improved over time (P = 0.007). There was no significant difference in DFS between microMTC and macroMTC patients. However, more advanced LN stage patients demonstrated more recurrences (P < 0.001). Especially, there were significantly more recurrences in patients with N1b diseases in comparison with patients without cervical LN metastases (P < 0.001). CONCLUSIONS: The prognosis of MTC patients has significantly improved in recent years. These changes could be associated with the early diagnosis before development of lateral and extensive cervical LN metastases. J. Surg. Oncol. 2016;113:152-158. © 2015 Wiley Periodicals, Inc.

Prognostic Value of the Number of Retrieved Lymph Nodes in Pathological Nx or N0 Classical Papillary Thyroid Carcinoma.

BACKGROUND: This study evaluated the clinical implications of the number of retrieved central lymph nodes (LN) for the recurrence and recurrence-free survival (RFS) outcomes in patients with pathological Nx (pNx) or N0 classical papillary thyroid carcinoma (PTC). METHODS: In total, 464 patients were enrolled following total thyroidectomy with central LN dissection. The risk factors related to recurrence and RFS were evaluated and compared between these groups. RESULTS: Age, primary tumor size, and number of retrieved central LNs were independent risk factors for recurrence according to multivariate analysis (p < 0.05). The cut-off value for the number of retrieved central LNs related to recurrence was 4.5. Group 2 (pN0; ≥5 nodes) demonstrated a significantly higher proportion of patients with an ablation-stimulated thyroglobulin (sTg) level <2.0 ng/mL (84.9 vs 61.1 %; p < 0.050) and control sTg level <1.0 ng/mL (92.1 vs 79.6 %; p < 0.050) in comparison with patients in group 1 (pNx or pN0; 1-4 nodes). Perioperative complication rates were comparable between groups. CONCLUSION: The number of retrieved central LNs is an independent risk factor for recurrence, even among patients with pNx or pN0 classical PTC. A thorough central LN dissection may therefore improve the long-term RFS rate.

Importance of the intraoperative appearance of preserved parathyroid glands after total thyroidectomy.

PURPOSE: Hypocalcemia after total thyroidectomy is a concern for every endocrine surgeon. We conducted this study to establish the value of the macroscopic appearance of preserved parathyroid glands after thyroidectomy in predicting post-thyroidectomy hypocalcemia. METHODS: In 2009, 237 patients underwent total thyroidectomy at our hospital. The macroscopic appearance of the preserved parathyroid glands was recorded and the serum calcium and intact parathyroid hormone levels were measured postoperatively. RESULTS: Thirteen patients (5.5 %) had transient hypocalcemia and 1 patient (0.4 %) had permanent hypocalcemia. All of the hypocalcemia patients with more than one normal preserved parathyroid had asymptomatic transient hypocalcemia that did not require medication. The sensitivity, specificity, positive predictive value, and negative predictive value for hypocalcemia with at least 1 normal preserved parathyroid were 78.6, 79.4, 19.3, and 98.3 %, respectively. CONCLUSION: The macroscopic appearance of preserved parathyroid glands and the number of well-preserved parathyroid glands after thyroidectomy proved effective in predicting post-thyroidectomy hypocalcemia.

Surgical Management of Familial Papillary Thyroid Microcarcinoma: A Single Institution Study of 94 Cases.

BACKGROUND: Familial papillary thyroid carcinoma (familial PTC) is well known to present with aggressiveness; however, the characteristics and the prognostic outcomes of familial papillary thyroid microcarcinoma (familial micro-PTC) are not well established. The overall aim of this study was to analyze the clinicopathological outcomes of familial micro-PTC. METHODS: Between 1996 and 2006, 2071 patients underwent thyroid surgery for papillary thyroid carcinoma. The clinicopathological outcomes for familial PTC and sporadic PTC were compared, and familial micro-PTC data were sub-analyzed. RESULTS: There were significant differences in multifocality, bilaterality, extent of surgery, and recurrence between familial PTC and sporadic PTC (p<0.05). There was no significant difference in the number of affected family members in the familial PTC group. In patients with familial micro-PTC, less aggressiveness was noted in multifocality, extrathyroidal invasion, tumor stage at time of initial surgery, central lymph node metastasis, and recurrence than in those with familial PTC tumors>1 cm in diameter (p<0.05). The multivariate analysis including recurrence showed no significant difference between familial micro-PTC patients and sporadic micro-PTC patients. CONCLUSION: When familial PTC was compared with sporadic PTC, our results support the recommendation for more invasive familial PTC surgery. However, familial micro-PTC outcomes differed from familial PTC tumors>1.0 cm in diameter. It was similar to sporadic micro-PTC, illustrating that familial micro-PTC is less aggressive and that a less invasive surgical treatment could be considered.