Prognostic factors for sporadic medullary thyroid carcinoma

Medullary thyroid cancer outcomes in patients with undetectable versus normalized postoperative calcitonin levels

BACKGROUND

Calcitonin (Ct) is a sensitive diagnostic biomarker and one of the most important prognostic factors in medullary thyroid cancer (MTC). This study aimed to evaluate progression-free survival and recurrence rates of MTC associated with undetectable compared with normalized serum Ct levels after surgery.

METHODS

This retrospective observational study included patients operated for MTC at the Digestive and Endocrine Surgery Department of Lyon Sud Hospital Centre between 2000 and 2019. Clinical and pathological factors were correlated with postoperative Ct concentrations. Undetectable and normalized Ct concentrations were defined as below 2 pg/ml and 2-10 pg/ml respectively.

RESULTS

Overall, 176 patients were treated for MTC, and 127 were considered biochemically cured after surgery. Of these, 24 and 103 had normalized and undetectable Ct concentrations respectively. Patients with Ct level normalization had a 25 per cent risk of disease recurrence, compared with 3 per cent in patients with undetectable Ct levels after surgery. The presence of metastasis in two or more compartments was predictive of failure to achieve undetectable Ct concentrations after surgery and an increased risk of recurrence.

CONCLUSION

Among patients with biochemically cured MTC, those with undetectable or normalized Ct concentrations after surgery had different risks of recurrence. Simply assessing postoperative Ct normalization can be falsely reassuring, and long-term follow-up is needed.

Impact of Advanced Age on the Clinical Presentation and Outcome of Sporadic Medullary Thyroid Carcinoma

Simple Summary

The clinical behavior of medullary thyroid carcinoma is heterogeneous and can be influenced by several clinical, biochemical and molecular factors. The role of age as a prognostic factor remains controversial. In our cohort of 432 sporadic medullary thyroid carcinoma, no differences in histologic features at diagnosis and in number and type of therapies performed during the follow-up were detected when dividing the patients according to age (< and ≥ 65 years). Younger patients had a longer follow-up and survival time, compared to the older patients. However, in dead patients, no differences in the aggressiveness of the disease at presentation and treatments performed during the follow-up were found between the two age groups.

Abstract

Sporadic medullary thyroid carcinoma (MTC) is a rare malignancy with a heterogeneous clinical course. Several potential prognostic factors have been investigated, but the impact of some of these is controversial, such as age at diagnosis. We evaluated the data of 432 sporadic MTC patients followed-up for a median of 7.4 years. Patients were divided and compared according to their age at diagnosis in group A (<65 years—n = 338, 78.2%) and group B (≥65 years—n = 94, 21.8%). No differences were detected between the two groups. Median follow-up time was significantly longer in patients <65 than ≥65 years. We observed 41 (9.5%) cancer-related death events. The death rate was similar between the two age groups. However, the Kaplan Meier curve showed a longer survival time for younger patients compared to older patients [HR 2.5 (CI 95%: 1.27–4.94), p < 0.01]. Nevertheless, no differences in the aggressiveness of the disease at presentation and in the number and type of treatments performed were found in the two subgroups of dead patients. In patients with sporadic MTC, age at diagnosis did not correlate with any clinical and pathological features. Cancer-related death events are similar in older and younger patients, but survival time is longer in the younger.

A Proposed Grading Scheme for Medullary Thyroid Carcinoma Based on Proliferative Activity (Ki-67 and Mitotic Count) and Coagulative Necrosis

We investigated the prognostic value of a range of histologic parameters in medullary thyroid carcinoma (MTC) to design a grading system to predict overall survival. We assessed 76 patients with MTCs undergoing primary tumor resection for age, sex, tumor size, vascular space invasion, lymph node metastasis, multiple endocrine neoplasia type 2 (MEN2) status, mitotic count, Ki-67 proliferative index, spindled morphology, sheet-like growth pattern, coagulative necrosis, incipient necrosis, nuclear grade, multinucleation, prominent nucleoli, fibrosis, and amyloid deposition. In addition to the clinical features of age and the diagnosis of MEN2, the only histologic features that significantly predicted reduced overall survival were Ki-67 proliferative index, mitotic count, and the presence of coagulative necrosis. Using a combination of these 3 variables, we propose a 3-tiered grading system based solely on proliferative activity (Ki-67 proliferative index and mitotic count) and necrosis. There were 62 (82%) low-grade MTCs (low proliferative activity, no necrosis), 9 (12%) intermediate grade (low proliferative activity and necrosis present, or intermediate proliferative activity and no necrosis), and 5 (7%) high grade (intermediate proliferative activity and necrosis present, or high proliferative activity with or without necrosis). The mean overall survival was 193, 146, and 45 months, respectively (P=0.0001) for the 3 grades. The grading system remained prognostic when controlled for other factors associated with survival including age and known MEN2 syndrome. We conclude that this proposed grading system, which uses only a combination of proliferative activity (Ki-67 index, mitotic count) and coagulative necrosis, is a strong predictor of overall survival in MTC.

Grading of medullary thyroid carcinoma on the basis of tumor necrosis and high mitotic rate is an independent predictor of poor outcome

Medullary thyroid carcinoma (MTC) is a rare nonfollicular cell-derived tumor. A robust grading system may help better stratify patients at risk for recurrence and death from disease. In total, 144 MTC between 1988 and 2018 were subjected to a detailed histopathologic evaluation. Clinical and pathologic data were correlated with disease specific survival (DSS), local recurrence free survival (LRFS)  and distant metastasis free survival (DMFS). Median age was 53 years (range: 3-88). Median tumor size was 1.8 cm (range: 0.2-11). Lymph node metastases were present in 84 (58%) cases while distant metastases at presentation were found in 9 (6%) patients. Seven (5%) had ≥5 mitoses/10 HPFs. Tumor necrosis was present in 30 cases (20%) while lymphovascular invasion occurred in 41 (28%) of tumors. Extra-thyroidal extension was found in 44 (31%) and positive margins were seen in 19 (14%). There was a strong correlation between increasing tumor size and tumor necrosis (p < 0.001). Median follow up was 39 months. In univariate analysis, male gender, higher American Joint Committee on Cancer (AJCC) stage group, larger tumor size, tumor necrosis, high mitotic index (≥5/10 HPF), nodal status, size of largest nodal metastasis, and elevated postoperative serum calcitonin predicted worse DSS, LRFS, and DMFS (p < 0.05). Extra-thyroidal extension correlated with DSS and DMFS while positive margins and distant metastasis at presentation imparted worse DSS (p < 0.05). In multivariate analysis, tumor necrosis and mitotic activity (5 mitosis/10 HPFs as the cutoff) were the only independent predictors for DSS (p = 0.008 and 0.026, respectively). Tumor necrosis was the sole independent prognostic factor for LRFS and DMFS (p = 0.001 and 0.003, respectively). The presence of tumor necrosis and high mitotic rate are powerful independent prognostic factors in MTC and outperform serum calcitonin and stage. We propose a grading system based on tumor necrosis and mitotic activity to better stratify MTC patients for counseling, post-resection surveillance, and therapy.

Static Prognostic Factors and Appropriate Surgical Designs for Patients with Medullary Thyroid Carcinoma: The Second Report from a Single-Institution Study in Japan

Background

Medullary thyroid carcinoma (MTC) originates from calcitonin-producing cells of the thyroid. In 2009, we published our first report on the biological characteristics and prognosis of 118 MTC patients. Herein, we enrolled a larger number of patients with longer follow-up periods to further study the biological characteristics and appropriate therapies for MTC.

Methods

In general, hemithyroidectomy and total thyroidectomy were performed for sporadic MTC confined to the thyroid lobe and for hereditary MTC with central node dissection, respectively. Moreover, prophylactic modified radical neck dissection was performed on the side of macroscopic tumors.

Results

In total, 233 patients (99 hereditary and 134 sporadic) were enrolled. The median follow-up time was 128 months (range 7–445 months). Biochemical cure was obtained in 36 (62%) of the 58 patients who underwent prophylactic MND and were pathologically positive for lateral node metastasis. None of the patients had recurrence in the preserved thyroid. Distant recurrence was detected in 19 patients, and 12 died of MTC. Preoperative calcitonin and carcinoembryonic antigen levels, tumor size (T) > 4 cm, the male sex, clinical and pathological node metastases (N1), distant metastasis (M1), extrathyroid extension (Ex), and a lack of biochemical cure had prognostic impacts on distant recurrence and/or carcinoma-related mortality on univariate analysis. On multivariate analysis, Ex was independently correlated with distant recurrence, and Ex, T > 4 cm, and M1 independently affected carcinoma-related mortality.

Conclusion

MTC patients had excellent prognosis in our institutions, indicating that our surgical strategies were appropriate.

Prognostic value of numbers of metastatic lymph node in medullary thyroid carcinoma: A population-based study using the SEER 18 database

Lymph node (LN) metastases are widely considered as a vital assessment of disease progression, as well as an essential indicator for biochemical cure of medullary thyroid carcinoma (MTC). Prognostic effect of numbers of metastatic LN has not been fully studied and the optimal cut-point of LN numbers has not been established. This population-based study designed to investigate prognostic value of numbers of positive LN and determinate the prognostic factors.Data were generated from Surveillance, Epidemiology, and End Results (SEER) database between 1998 and 2013. X-tile program was applied and cut points for division of LN numbers as low-, medium- and high-risk were 0, 1 to 10, and ≥11. The relationship between numbers of metastatic LN, age, tumor size, extent of tumor, and radiotherapy on overall survival (OS) and disease-specific survival (DSS) were evaluated.A total of 1466 diagnosed primary MTC patients without metastases were eligible for analysis in current study. 945 (64%) patients were classified as no positive LNs, 327 (22%) as 1 to 10 positive LNs, 194 (14%) as ≥11 positive LNs. Patients with older age, tumor size, ≥11 positive LN were associated with unfavorable OS. Those dispensed with radiation had statistically better prognosis than the others. When stratified by age, there was a significant difference in patients ≥45 years within LN categories (log-rank P < .001). When stratified by tumor size, a significant correlation was noted between rising numbers of involved nodes and falling rates of OS in tumor measuring >2cm setting (2-4 cm setting, log-rank P = .003 and >4 cm setting, log-rank P = .014, separately). There was no statistical difference of the area under the curve (AUC) for OS and DSS prediction between LN group and N stage, suggesting the 2 LN systems had the same predictive power for OS and DSS.Numbers of metastatic LN showed prognostic power in survival analysis and remained an independent survival predictor which can be evaluated in MTC treatment decisions for optimum assessment.

Clinical significance of RET and RAS mutations in sporadic medullary thyroid carcinoma: a meta-analysis

There are ongoing debates with respect to the prognostic roles of molecular biomarkers in sporadic medullary thyroid carcinoma (MTC). In this study, we aimed at investigating the prognostic value of RET and RAS mutations - the two most common mutations in sporadic MTCs. A search was conducted in four electronic databases. Relevant data were extracted and pooled into odds ratios (OR), mean differences (MD) and corresponding 95% confidence intervals (CI) using the random-effect model. We used Egger's regression test and visual of funnel plots to assess the publication bias. From 2581 studies, we included 23 studies with 964 MTCs for meta-analysis. Overall, the presence of RET mutation was associated with an elevated risk for lymph node metastasis (OR = 3.61; 95% CI = 2.33-5.60), distant metastasis (OR = 2.85; 95% CI = 1.64-4.94), advanced tumor stage (OR = 3.25; 95% CI = 2.02-5.25), tumor recurrence (OR = 3.01; 95% CI = 1.65-5.48) and patient mortality (OR = 2.43; 95% CI = 1.06-5.57). RAS mutation had no significant prognostic value in predicting tumor aggressiveness. To summarize, our results affirmed that RET mutation is a reliable molecular biomarker to identify a group of highly aggressive sporadic MTCs. It can help clinicians better assess patient prognosis and select appropriate treatment decisions.

Persistent Hypercalcitoninemia in Patients with Medullary Thyroid Cancer

Medullary thyroid carcinoma is a highly malignant and progressive disease. Surgery is the only effective treatment. Calcitonin is a significant marker for medullary thyroid carcinoma, and due to its sensitivity it represents a useful tool for the follow-up. The outcome of patients affected by medullary thyroid carcinoma depends on tumor size, lymph node involvement, and adequacy of primary surgical management. In the present study, the authors reviewed their own experience in the cure of medullary thyroid carcinoma. Forty-one patients operated for sporadic medullary thyroid carcinoma were included. Indications for surgery, inclusive of lymphectomy techniques, timing of redo surgery, and the meaning of calcitonin levels in highlighting disease are extensively discussed. Patients with elevated calcitonin levels and favorable outcome are considered, together with the various diagnostic tools to be employed during patient workup.

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.

Medullary thyroid carcinoma: a 30-year experience at one institution in Korea

PURPOSE

The objective of this study was to review the clinical outcome and prognosis of patients with sporadic and hereditary medullary thyroid cancer (MTC) who were treated at a single tertiary hospital in Korea.

METHODS

We retrospectively reviewed the case files of 85 patients treated from August 1982 to February 2012.

RESULTS

In all, 65 patients (76.5%) had sporadic MTC and 20 patients (23.5%) had hereditary MTC. Patients in the sporadic group were older than in the hereditary group (P < 0.001). However, the hereditary group had more tumor multiplicity (P < 0.001) and bilaterality (P < 0.001). Neither survival rate was significantly different between the sporadic and hereditary groups (P = 0.775 and P = 0.866). By multivariate analysis, distant metastasis was a significant prognostic factor for overall and progression-free survival.

CONCLUSION

In general, patients with MTC have favorable outcomes. Distant metastasis appears to be the strongest predictor of overall and progression-free survival.

Multifocality in Sporadic Medullary Thyroid Carcinoma: An International Multicenter Study

BACKGROUND

Current surgical standard of care in sporadic medullary thyroid carcinoma (sMTC) consists of a minimum of total thyroidectomy with central neck dissection. Some have suggested thyroid lobectomy with isthmusectomy and central neck dissection for patients with sMTC, given their lower frequency of bilateral disease, although this topic has not been thoroughly studied. This study assessed the prevalence of multifocality in sMTC via a large international multi-institutional retrospective review to quantify this prevalence, including the impact of geography, to assess more accurately the risks associated with alternative surgical approaches.

METHODS

A retrospective chart review of sMTC patients from 11 institutions over 29 years (1983-2011) was undertaken. Data regarding focality, extent of disease, RET germline analysis plus family and clinical history for multiple endocrine neoplasia type 2 (MEN2), and demographic data were collected and analyzed.

RESULTS

Patients from four continents and seven countries were included in the sample. Data for 313 patients with documented sMTC were collected. Of these, 81.2% were confirmed with negative RET germline testing, while the remaining 18.8% demonstrated a negative family history and no manifestations of MEN2 syndromes other than MTC. Bilateral disease was identified in 17/306 (5.6%) patients, while multifocal disease was noted in 50/312 (16.0%) sMTC patients. When only accounting for germline negative patients, these rates were not significantly different (5.6% and 17%, respectively). Among them, when disease was unifocal in the ipsilateral lobe and isthmus, bilateral disease was present in 6/212 (2.8%) cases. When disease was multifocal in the ipsilateral lobe or isthmus, then bilateral disease was present in 8/37 (21.6%) cases (p < 0.001). No geographic differences in focality were identified.

CONCLUSIONS

The 5.6% prevalence of bilateral foci in sMTC suggests that total thyroidectomy should remain the standard of care for initial surgery, as less complete thyroid surgery may fail to address fully the primary site of disease. Whether ipsilateral tumor focality should be an independent factor determining the need for completion thyroidectomy when sMTC is diagnosed after hemithyroidectomy remains to be determined.

Results of Surgical Therapy in Patients with Medullary Thyroid Carcinoma

Medullary thyroid carcinoma (MTC) is a rare form of malignancy, having an intermediate prognosis. Controversies exist regarding the best surgical approach. The aim of the study was to analyze the outcome in a group of patients with MTC, diagnosed and followed up in a single care center. We performed a retrospective analysis of all the patients diagnosed with MTC in the Department of Endocrinology from the County Emergency Hospital Timisoara between 1992 and 2012. The study group included 19 patients, 6 men (31.6 %), mean age 41.2 ± 12.5 years (20-72 years). The preoperative diagnosis was based on the protocol for nodular thyroid disease. Total or near-total thyroidectomy was performed in 10 out of 16 patients who could be operated. Postoperative follow-up included repeated measurements of serum calcitonin and imaging investigations. Nine out of the total of 19 (47.3 %) patients had hereditary forms of MTC. Most of the cases (84.2 %) were submitted to surgery. The median duration of follow-up was 84 months. The pTNM staging indicated that the majority of the patients with hereditary MTC were diagnosed in an earlier stage. Disease remission was achieved in 7 cases (43.8 %). Four patients, all with sporadic forms, died. Survival rates at 1, 5 and 10 years were significantly higher (p = 0.048) in patients with hereditary MTC. An early diagnosis of MTC allows a better surgical approach and an improved survival rate. We support the general recommendation that modified radical neck dissection is not necessary for all the patients with MTC.

One-step nucleic acid amplification testing in medullary thyroid cancer lymph nodes: a case series

INTRODUCTION

Locoregional relapse in medullary thyroid cancer (MTC) may be caused by nodal micrometastases. Medullary thyroid cancer lymph nodes have not yet been evaluated by one-step nucleic acid amplification (OSNA). Therefore, the aim of this study was to detect MTC cells by OSNA in cervical lymph nodes and compare the obtained outcomes with conventional histopathology.

MATERIAL AND METHODS

Twenty-one randomized, unenlarged lymph nodes from 5 patients with MTC were examined by histopathology and OSNA. Lymph nodes were divided into four representative blocks by a sterile, single use, special cutting device in the same way as in the clinical protocol study performed by Tsujimoto et al. Two blocks were used for histopathology and immunohistochemistry, 2 for OSNA.

RESULTS

Positive results of histopathology and OSNA were revealed in 4 patients. The outcomes of OSNA and histopathology were corresponding in 3 patients. Positive histopathology results of 2 lymph nodes from 2 patients were confirmed by OSNA. In 1 patient there were only negative results of both examinations. One-step nucleic acid amplification failed to detect metastasis in 1 lymph node in 2 patients although it did not change the TNM status in these patients. There were no false positive results in the OSNA test.

CONCLUSIONS

One-step nucleic acid amplification may be an alternative method to histopathology in detecting nodal involvement in MTC. Further studies should evaluate the sensitivity and specificity of OSNA and the impact on staging in MTC.

Medullary thyroid carcinoma: the influence of policy changing in clinical characteristics and disease progression

OBJECTIVE

Medullary thyroid carcinoma (MTC) has varying clinical course. We assessed trends in MTC presentation during the last 34 years.

DESIGN

Retrospective study.

METHODS

One hundred and fifty one patients (44.4% males) were followed for 0.934 years. Patients were classified according to year of diagnosis: group 1, 1977-2000 (n=53) and group 2, 2001-2011 (n=98). Extent of disease at diagnosis, during follow-up, number of surgeries, and pre- and postoperative calcitonin levels were recorded.

RESULTS

In total, 48.34% reported family history of MTC. Group 1 had larger tumors (median 1.70 (intraquartile range (IQR) 1.7) vs 1.1 (1.2) cm, P=0.045, Mann-Whitney), they presented less frequently micro-MTCs (27.8 vs 46.1%, P=0.045), and underwent more multiple surgeries (63.3 vs 20.0%, P<0.001). Group 1 had more frequently progressive disease (35.8 vs 12.2%, P=0.003) and distant metastasis at follow-up (39.7 vs 17.4%, P=0.017). Chronological group (HR 0.15, 95% CI 0.03-0.68, P=0.015) and distant metastases at follow-up (HR 0.07, 95% CI 0.015-0.30, P=0.001) were independently associated with 10-year disease progression (P<0.001). In sporadic cases, cervical lymph node invasion and distant metastases at diagnosis were more frequent in group 1 (72.7 vs 45.5%, P=0.032 and 27.3 vs 5%, P=0.019 respectively); disease stage at diagnosis was more advanced (P=0.004). They underwent more multiple surgeries (P<0.001), presented more frequently distant metastasis at follow-up (67.7 vs 20.0%, P=0.002), had less frequently remission, and more frequently progressive disease (21.4 vs 58.0% and 64.3 vs 14.0% respectively, P<0.001). Postoperative calcitonin levels were higher (P=0.024).

CONCLUSIONS

Recently, an increase in micro-MTCs is observed, while indices of invasiveness and persistence of disease are better. Increased awareness in familial cases, routine calcitonin measurements, and improved surgical procedures could be responsible.

Validity of 6(th) edition of UICC TNM classification system for medullary thyroid carcinoma: a proposal for intraoperative evaluation of T category

Medullary thyroid carcinoma (MTC) accounts for 1.4% of all thyroid malignancies in Japan. Here, we studied the validity of a staging system evaluated preoperatively (Stage), intraoperatively (intra-Stage), and pathologically (pStage) based on the 6(th) and 7(th) UICC TNM classifications. One hundred and nineteen MTC patients who did not show distant metastasis at diagnosis and underwent locally curative surgery were enrolled in this study (average follow-up period: 173.4 months). Twenty-year clinical (not biochemical) disease-free survival (DFS) rates of Stage I, II, III, and IVA patients based on the 6(th) edition were 100, 88.2, 66.8, and 38.9%, respectively. DFS of Stage IVA patients was significantly poorer than that of Stage III patients (p = 0.03137). However, using the 7(th) edition, only 1 patient was classified with Stage III. Intra-Stage III patients based on the 6th edition showed a significantly poorer DFS (20-year DFS 50.0%) than intra-Stage II patients (92.9%) (p = 0.02668), and DFS of intra-Stage IVA patients (38.9%) tended to be poorer than that of intra-Stage III patients (p = 0.05439). Only one patient was classified with intra-Stage III using the 7(th) edition. In pStage, as many as 56 patients (47.1%) were classified with pStage IVA employing both editions. Taken together, Stage and intra-Stage were more useful to accurately discriminate high-risk patients than pStage, and their 6(th) editions were better than 7(th) editions. Although the number of patients was small, our data showed the possibility that intra-Stage in the 6(th) edition was the best staging system for MTC patients.

Changes in risk factors and Tumor Node Metastasis stage of sporadic medullary thyroid carcinoma over 41 years, before and after the routine measurements of serum calcitonin

The measurement of serum calcitonin (CT) in all thyroid nodules for the detection of medullary thyroid carcinoma (MTC) is controversial. We compare several prognostic factors, Tumor Node Metastasis (TNM) stage, and survival in sporadic MTC patients operated on before and after the use of routine measurements of serum CT in combination with thyroid ultrasonography (US). Thirty-seven patients had been operated on between 1969 and 1989 (group I), before the use of routine measurements of serum CT and the routine use of thyroid US, and 39 (group II) had been operated on between 1990 and 2009, after the introduction of routine use of serum CT and thyroid US. There were no between-group differences concerning age and sex. Group I had larger tumors at the time of operation (P < .001) and higher postoperative serum CT levels (P < .001). Cervical lymph node and distant metastases were found more frequently in group I in comparison with group II. The cases with TNM stage I were significantly higher in group II than in group I, in contrast with the cases with TNM stage IV that were significantly higher in group I. Univariate analysis revealed a significantly higher 15-year survival rate in group II than in group I (P = .002). The postoperative CT levels were positively correlated with tumor size (P < .001). During the last 2 decades, the diagnosis of sporadic MTC at an earlier stage has been made possible by the routine use of serum CT in combination with thyroid US. The significant increase of the 15-year survival rate shows better outcome in these patients.

Medullary Thyroid Cancer: It is a pain in the neck?

Background: Medullary thyroid cancer (MTC) commonly presents with lymph node (LN) metastases, and has a worse prognosis than papillary thyroid cancer (PTC). Tumor size and LN involvement have been shown to affect stage of disease; however, to our knowledge, ours is the first study that attempts to correlate anterior neck pain on presentation with the extent of disease.

Methods: We performed a retrospective review of patients with MTC who underwent an operation from February 1998 through December 2008. We compared the symptom of anterior neck pain with the pathologic extent of disease. Our control group comprised patients who underwent an operation for PTC. Analysis was performed using the Fisher's exact test and the Mann-Whitney test.

Results: Of the 109 patients with MTC, 50 (46%) met our inclusion criteria. Of the 50 patients with MTC, 11 presented with neck pain, compared to 3 of the 50 patients with PTC (p = 0.041). Of those 11 patients, 9 (82%) had LN involvement on final pathology, as compared with 14 (36%) of the 39 without neck pain (p = 0.014). Of patients with neck pain, 18% were diagnosed at stage I to II and 82% at stage III to IV, compared to 64% at stage I to II and 36% at stage III to IV (p = 0.014).

Conclusions: Our study demonstrates that more patients with MTC present with anterior neck pain than do patients with PTC and that patients with MTC and neck pain have an increased risk of LN metastases. The results of this study suggest that MTC patients, who present with concomitant neck pain, should undergo a total thyroidectomy, prophylactic bilateral central neck dissection, and ipsilateral lateral neck dissection.

Predictive value of the Delphian and level VI nodes in papillary thyroid cancer

BACKGROUND

Recent published data has shown that metastatic involvement of the prelaryngeal or Delphian lymph node (DLN), the highest of the central (level VI) cervical lymph nodes, is highly predictive of advanced nodal disease in papillary thyroid cancer (PTC). The aims of this study were to determine the diagnostic accuracy of all the level VI cervical nodes in PTC and to determine which node group, if any, is the most accurate in predicting lateral node (N1b) disease.

METHODS

This was a retrospective cohort study. Data were obtained from the University of Sydney Endocrine Surgical Unit Database and through a review of the histopathology records. The study cohort was composed of 177 consecutive patients with a final diagnosis of PTC who underwent total thyroidectomy and lymph node dissection, spanning the period from May 2001 to December 2006.

RESULTS

Of the 177 patients with PTC, 86 had the DLN removed, 51 had a pretracheal node removed and 76 had the paratracheal group removed. DLN, paratracheal and pretracheal node disease was present in 21%, 39% and 46%, respectively. Lateral node (N1b) disease was present in 35%. Paratracheal node involvement was mildly predictive of further disease with patients 1.7 times more likely to have lateral node involvement (sensitivity=55%, specificity=68%). Pretracheal node involvement was moderately predictive of further disease with patients three times more likely to have lateral node involvement (sensitivity=72%, specificity=74%). DLN involvement was highly predictive of further node involvement with patients nine times more likely to have lateral node disease (sensitivity=53%, specificity=94%) and 40 times more likely to have any nodal disease (sensitivity=41%, specificity=100%).

CONCLUSION

This is the first study to examine the diagnostic accuracy of all level VI lymph nodes in PTC. While, metastatic involvement of all central nodal groups is indicative of further disease, the DLN is the most accurate predictor.

Alternative surgical strategies and favorable outcomes in patients with medullary thyroid carcinoma in Japan: experience of a single institution

BACKGROUND

Medullary thyroid carcinoma (MTC) accounts only for 1.4% of all thyroid malignancies in Japan. Since 1996, we have performed hemithyroidectomy, instead of total thyroidectomy, for sporadic nonhereditary MTC when the primary lesion is located in only one lobe. Regarding lymph node dissection, modified radical neck dissection (MND) at least ipsilateral to the tumor has been routinely performed, even if there is no clinically apparent metastasis. We investigated the clinical outcomes of MTC patients in our department.

METHODS

A series of 118 patients with MTC who underwent initial surgery between 1975 and 2005 were enrolled in this study. The RET gene mutations were analyzed for all patients and 46 had germline RET gene mutations. Of those 46 patients, 26 were diagnosed as MEN 2A and 2 were diagnosed as MEN 2B. Postoperative follow-up periods averaged 141 months.

RESULTS

Of 115 patients who did not have distant metastasis at surgery and who underwent locally curative surgery, 78 (67.8%) were biochemically cured. All patients without pathological lymph node metastasis were biochemically cured, and 44.8% of patients with node metastasis were also biochemically cured. The 10-year and 20-year disease-free survival rates were 89.0% and 82.5%, respectively. None of the patients who did not show lymph node metastasis and only 2 (2.6%) of 78 patients who were biochemically cured showed clinically apparent carcinoma recurrence. The 10-year and 20-year cause-specific survival rates were 96.6% and 91.7%, respectively. Lymph node metastasis, tumor size>4 cm, extrathyroid and extranodal tumor extensions significantly affected cause-specific survival of patients.

CONCLUSIONS

Clinical outcomes of MTC patients in our series were better than those in Western countries, a result that might have resulted in part because of our routine MND regardless of whether clinically apparent node metastasis was detected.

Sporadic medullary thyroid carcinoma: clinical data from a university hospital

INTRODUCTION

Medullary thyroid carcinoma may occur in a sporadic (s-medullary thyroid carcinoma, 75%) or in a multiple endocrine neoplasia type 2 form (MEN2, 25%). These clinical forms differ in many ways, as s-medullary thyroid carcinoma cases are RET-negative in the germline and are typically diagnosed later than medullary thyroid carcinoma in MEN2 patients. In this study, a set of cases with s-medullary thyroid carcinoma are documented and explored.

PURPOSE

To document the phenotypes observed in s-medullary thyroid carcinoma cases from a university group and to attempt to improve earlier diagnosis of s-medullary thyroid carcinoma. Some procedures for diagnostics are also recommended.

METHOD

Patients (n=26) with apparent s-medullary thyroid carcinoma were studied. Their clinical data were reviewed and peripheral blood was collected and screened for RET germline mutations.

RESULTS

The average age at diagnosis was 43.9 years (+/- 10.82 SD) and did not differ between males and females. Calcitonin levels were increased in all cases. Three patients presented values that were 100-fold greater than the normal upper limit. Most (61.54%) had values that were 20-fold below this limit. Carcinoembryonic antigen levels were high in 70.6% of cases. There was no significant association between age at diagnosis, basal calcitonin levels or time of disease onset with thyroid tumor size (0.6-15 cm). Routine thyroid cytology yielded disappointing diagnostic accuracy (46.7%) in this set of cases. After total thyroidectomy associated with extensive cervical lymph node resection, calcitonin values remained lower than 5 pg/mL for at least 12 months in eight of the cases (30.8%). Immunocyto- and histochemistry for calcitonin were positive in all analyzed cases. None of the 26 cases presented germline mutations in the classical hotspots of the RET proto-oncogene.

CONCLUSION

Our cases were identified late. The basal calcitonin measurements and immunostaining for calcitonin were highly useful for diagnosing s-medullary thyroid carcinoma. The rate of complete patient recovery was low, and none of the parameters analyzed were useful predictors of the thyroid tumor size. Our findings support previous recommendations for routine serum calcitonin evaluation and immunostaining analysis involving single thyroid nodules.

Long-term outcome of reoperations for medullary thyroid carcinoma

BACKGROUND

Most patients with medullary thyroid carcinoma (MTC) have persistent disease after primary surgery, as evidenced by calcitonin elevation. Previous reports showed that reoperation on selected patients yields immediate calcitonin normalization in one-third of patients. Long-term follow-up data are needed to assess the outcome in such patients. This report aims to provide 8- to 10-year follow-up on reoperations for persistent or recurrent MTC.

METHODS

An Internal Review Board (IRB) approved database on patients treated for MTC has been prospectively maintained. This database was reviewed to report follow-up data on calcitonin levels and survival.

RESULTS

Between 1992 and 2006, 148 patients underwent reoperations for recurrent or persistent MTC (55 patients had 59 reoperations for palliation, and 93 patients had 105 reoperations for cure). Of the 93 patients operated on for cure (44 with hereditary MTC, 49 with the sporadic form), 8-10-year follow-up data were available on 56. Four patients died of disease (4.3% of 93). Two died of unrelated causes, and were excluded from calcitonin outcome analysis. Fourteen patients of 54 (26.0%) have unstimulated calcitonin levels of <10 pg/ml at 8-10 years. Eleven additional patients (20.4%) have levels<100 pg/ml. None of these 25 patients (46.4%) have radiologic recurrence.

CONCLUSIONS

Previous reports demonstrated the low morbidity of reoperation for MTC in experienced hands, and success was determined by lowering of calcitonin levels. Follow-up data demonstrate that at least one third of such patients have long-term eradication of their disease following reoperation, as evidenced by biochemical and imaging studies.

Surgical approach to medullary thyroid cancer

Medullary thyroid cancer (MTC) compromises 3-5% of all thyroid cancers and arises from parafollicular or calcitonin-producing C cells. It may be sporadic (75% of cases), or may occur as a manifestation of either the hereditary syndrome Multiple Endocrine Neoplasia type 2 (MEN 2A or MEN 2B) (25% of cases), or rarely as an isolated familial syndrome (FMTC). Complete surgical resection comprising in most cases total thyroidectomy with central lymph node dissection at an early stage of the disease is the only potential cure for MTC. The familial form of the disease, MEN-2A occupies a unique place in surgical history, having been the first disease where surgical removal of an affected organ was undertaken before the development of malignancy, solely on the basis of genetic testing. Total thyroidectomy prior to the development of invasive cancer completely avoids an otherwise lethal malignancy. Timing of prophylactic surgery is based on models that utilise genotype-phenotype correlations, which have now been stratified into three risk groups based on the specific codon involved. MTC should be followed with postoperative serial serum calcitonin levels to survey for persistent or recurrent disease as indicated by detectable levels. The challenge however, if calcitonin levels are increased, is to find the source of its production. The first localisation technique recommended would be ultrasound of the neck, since there is a high frequency of local recurrence and cervical node metastasis, followed by a total body CT scan and bone scintigraphy.

Prognostic value of lymph node yield and metastatic lymph node ratio in medullary thyroid carcinoma

INTRODUCTION

Lymphadenectomy and thyroidectomy is standard treatment for medullary thyroid carcinoma (MTC), but the prognostic importance of the number of lymph nodes removed (lymph node yield, LNY) and the proportion of metastatic lymph nodes resected (metastatic lymph node ratio, MLNR) is unknown. We hypothesized that MTC survival is influenced by LNY and MLNR.

METHODS

Patients (N = 534) who underwent thyroidectomy with lymphadenectomy for MTC between 1988 and 2004 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method was used for univariate comparisons of survival for LNY and MLNR with a maximum follow-up of 12 years. Cox regression models adjusted for age, sex, extent of disease, tumor size, nodal status, LNY, and MLNR.

RESULTS

By univariate analysis, increasing LNY was associated with improved survival in all patients (P < 0.002) and node-positive patients (P < 0.001). In a multivariate analysis using LNY and MLNR as categorical variables, significant factors influencing survival included: age (P < 0.001), tumor size (P < 0.001), LNY (P = 0.007), and MLNR (P < 0.02); in node-negative patients: age (P = 0.002); in node-positive patients: age (P < 0.001), tumor size (P < 0.001), and LNY (P = 0.001). Using LNY and MLNR as continuous variables, significant factors influencing survival included: age (P < 0.001), tumor size (P < 0.001), and MLNR (P = 0.01); in node-negative patients: age (P < 0.001); in node-positive patients: age (P < 0.001) and tumor size (P < 0.001).

CONCLUSION

In patients undergoing thyroidectomy and lymphadenectomy for MTC, LNY and MLNR predict poorer survival, but their impact on survival was limited to node-positive patients and was otherwise dominated by the effects of age and extent of disease.

The Delphian lymph node in thyroid cancer

OBJECTIVE

To determine the significance of Delphian lymph node (DLN) involvement in thyroid cancer.

SUMMARY BACKGROUND DATA

The DLN has long been regarded as a predictor of thyroid malignancy and indicator of advanced disease; however, there are no published data in relation to the thyroid.

METHODS

A retrospective cohort study with data obtained from the University of Sydney Endocrine Surgery database and histopathology records. The study cohort comprised 1000 consecutive patients undergoing total thyroidectomy.

RESULTS

The DLN was separately removed and identified as such in 263 of 1000 (26.3%) patients. Of 1000 patients 203 (20.3%) had a diagnosis of papillary/medullary cancer. Of this group 150 patients had surgery performed for suspected cancer, and in 53 the diagnosis of cancer was unsuspected. In only 1 case did the DLN operative appearance alert the surgeon to an otherwise unsuspected thyroid cancer. The DLN was separately identified in 103 patients with cancer and, in this group, 22 of 103 (21.4%) had DLN metastases. DLN involvement was associated with greater nodal disease (9.8 vs. 1.6 nodes; P < 0.001), larger tumor size (19.4 vs. 11.1 mm; P < 0.003) and younger age (41 vs. 47 years; P = 0.058). DLN involvement was highly predictive of further disease in the central compartment (sensitivity = 41%, specificity = 95%), moderately predictive of further disease in the lateral compartment (sensitivity = 50%, specificity = 88%), and strongly suggestive of further nodal disease in the neck (sensitivity = 64%, specificity = 100%).

CONCLUSIONS

Although the clinical appearance of the DLN is not an accurate indicator of the presence of unsuspected thyroid cancer, metastatic involvement of the DLN is an adverse prognostic marker in papillary/medullary thyroid cancer. The presence of DLN metastasis in patients with thyroid cancer should alert the surgeon to the high probability of advanced disease and need for greater attention to the central and lateral lymph node compartments.

Long-term clinical and biochemical follow-up in medullary thyroid carcinoma: a single institution's experience over 20 years

OBJECTIVE

Many patients with medullary thyroid carcinomas (MTC) have reoperative surgery in different hospitals, which makes their follow-up difficult. To comprehend these complex courses and to find relevant prognostic factors we report a 20-year single center experience of 289 patients with MTC or precursor C-cell-hyperplasias.

PATIENTS AND METHODS

Between April 1986 and May 2006, 289 consecutive patients with MTC or MEN2 gene carriers were treated at the Department of Surgery at the University Hospital Düsseldorf. Tumor stages were documented according to the classification of the International Union against Cancer 5th edition, 1997 (Schott. Endocr Relat Cancer. 2006;13:779-795). A system to easily comprehend operative procedures is suggested.

RESULTS

There were 159 female and 130 male patients (f/m ratio 1.22). Mean age at time of diagnosis was 32 years (4-77) in the familial cases and 53 years (23-84) years in the sporadic cases. Sixty-six patients (23%) had multifocal disease. Twelve MEN2-patients had only C-cell-hyperplasia (pT0). Tumor stage was pT1 in 86 patients, pT2 in 106 patients, pT3 in 25 patients, pT4 in 52 patients and unclear in 8 patients. In the 289 patients 648 operations were performed. One hundred seventy patients had more than 1 operation (59%). Ninety-nine patients (34%) are calcitonin-negative and 91 patients (31%) live with elevated calcitonin. Median follow-up time of the surviving 211 patients was 8.9 years (range, 0.3-30.7 years). The 5- and 10-year survival of all tumor patients was 86% and 68%, respectively.

CONCLUSION

The chance to achieve biochemical cure in MTC is clearly dependent on the primary tumor size. The chance for long-term biochemical cure in a pT4-tumor is almost nil even after multiple and extended reoperations, whereas a pT1 tumor can be cured in up to 67% of the patients. Long-term survival, however, can be achieved even in pT4 tumor patients in almost 50%.

Medullary thyroid cancer: a retrospective analysis of a cohort treated at a single tertiary care center between 1970 and 2005

OBJECTIVE

To identify prognostic factors of clinical outcome and long-term survival in medullary thyroid cancer (MTC).

DESIGN

Retrospective case series of 51 consecutive patients (mean age 46.9 years, 57% female) treated at a single tertiary university medical center from 1970 to 2005. Medical records were reviewed for demographic data, laboratory and clinical course, treatment, and long-term outcome.

MAIN OUTCOME

At presentation, 25 patients (49%) had local disease and 26 (51%) had metastatic disease (three with distant metastases). RET mutations were identified in nine of 23 patients tested. The patients with hereditary disease were younger than the patients with sporadic disease (p < 0.001) and had lower calcitonin levels at diagnosis (p = 0.004) and more multicentric tumors (p = 0.02). Initial surgery consisted of total thyroidectomy in 47 patients, with neck dissection in 26; 22 patients achieved long-term remission. The 5-, 10- and 15-year survival rates were 88%, 85%, and 77%, respectively. On univariate analysis, distant metastases during the course of the disease and elevated calcitonin levels postoperatively were significant prognostic factors of reduced survival (p = 0.001 and 0.016, respectively). Lymph node involvement at initial surgery was associated with a lower remission rate (p = 0.016) but had no impact on long-term survival (p = 0.269).

CONCLUSION

Patients with MTC have a generally favorable outcome, perhaps owing to recent advances in diagnosis and treatment. Although postoperative serum calcitonin level and distant metastases are the only determinants of long-term survival, the presence of cervical metastases is predictive of a higher risk of recurrent or persistent disease.