Nationwide survey on the treatment policy for well-differentiated thyroid cancer -- results of a questionnaire distributed at the 37th meeting of the Japanese Society of Thyroid Surgery

Thyroid cancer surgery guidelines in an era of de-escalation

Well-differentiated thyroid carcinoma has seen a tremendous rise in global incidence over the past three decades, largely owing to widespread screening and identification of small, incidentally detected tumors. With this increased incidence has emerged a movement questioning whether all cases of thyroid cancer merit a treatment approach focused on oncologic completeness. Such trends towards thoughtful, evidence-based treatment de-escalation paradigms reflect better risk stratification of thyroid cancers, and recognition that not all detected disease poses a threat to health or survival. Thus, national and professional guidelines are evolving to incorporate higher thresholds for surgery, acceptance of less than total thyroidectomy in specific circumstances, higher thresholds for adjuvant therapy, and introduction of the role of active surveillance for selected cases of low risk disease. Despite these common themes, there are significant differences among guidelines. This lack of consensus in guidelines persists due to variation in clinical practice patterns, differences in consideration and interpretation of existing evidence, cultural and geographical considerations, and resources available for both diagnosis and treatment.

Changing trends in the management of well-differentiated thyroid carcinoma in Korea

A questionnaire administered in 2009 found that members of the Korean Association of Thyroid-Endocrine Surgeons (KATES) favored more aggressive treatment of well-differentiated thyroid carcinoma (WDTC) than physicians from other countries. This study assessed the changes in practical management of WDTC in Korea from the previous survey. Questionnaires were sent by e-mail to KATES members. A total of 101 members completed the questionnaire. Their responses were compared with response for the 2009 survey. Of the respondents, 53.5% and 80.2% indicated that they would perform fine-needle aspiration cytology on nodules that were <0.5 cm and 0.5-1.0 cm in diameter, respectively. If the cytology was positive, a large number of respondents favored surgical treatment, regardless of tumor size. Compared with the 2009 survey, a slightly higher percentage favored observation for patients with tumors that were <0.5 cm in diameter, and a larger percentage recommended less-than-total thyroidectomy for patients with T1 cancers. Respondents in 2014 favored aggressive lymph node dissection less, irrespective of tumor size, preferring short-term treatment with thyroid stimulating hormone suppressors. The percentage preferring postoperative high-dose radioactive iodine therapy slightly increased, whereas the percentage favoring external irradiation decreased, in 2014 compared with 2009. The management of Korean patients with WDTC changed from 2009 to 2014. In 2009, Korean respondents favored more aggressive treatment of WDTC compared with respondents from other countries. In 2014, however, Korean respondents favored a more conservative approach, especially in patients with microcarcinomas.

Recurrence pattern after conservative surgery for papillary thyroid carcinoma

OBJECTIVE

Risk-based treatment represents the optimal management strategy for papillary thyroid carcinoma; however, the optimal extent of thyroidectomy and neck dissection remains controversial. This study aims to clarify the pattern of recurrence after conservative surgery in patients with papillary thyroid carcinoma.

METHODS

We retrospectively reviewed 93 patients with papillary thyroid carcinoma treated with conservative surgery. We analyzed recurrence rate, recurrence pattern, risk factors for recurrence, salvage treatment, and disease-free survival (DFS) in patients stratified according to risk.

RESULTS

The recurrence rate was significantly lower in the low-risk group compared with the high-risk group (14% vs 34%; p<0.01). The recurrence pattern also differed between the two groups, with ipsilateral lateral neck recurrence being more common in the low-risk group (9%), while contralateral lateral neck recurrence was more common in the high-risk group (18%). Patients with contralateral thyroid lobe metastasis and/or direct contralateral thyroid lobe invasion showed a significantly higher rate of contralateral lateral neck metastasis than patients negative for both these features. The overall 5-year DFS was 81% in all patients. Advanced T and N classification, large primary tumor (≥4cm), extrathyroidal invasion, and high-risk group were significantly associated with poorer 5-year DFS in univariate analysis.

CONCLUSION

Conservative surgery may represent a good treatment option for patients with low-risk papillary thyroid carcinoma. Tumor recurrence patterns differ between risk groups, with contralateral thyroid lobe lesions and direct contralateral lobe invasion being risk factors for contralateral lateral neck recurrence.

Radioactive iodine (131I) therapy for differentiated thyroid cancer in Japan: current issues with historical review and future perspective

Radioactive iodine (RAI, (131)I) has been used as a therapeutic agent for differentiated thyroid cancer (DTC) with over 50 years of history. Recently, it is now attracting attention in medical fields as one of the molecular targeting therapies, which is known as targeted radionuclide therapy. Radioactive iodine therapy (RIT) for DTC, however, is now at stake in Japan, because Japan is confronting several problems, including the recent occurrence of the Great East Japan Disaster (GEJD) in March 2011. RIT for DTC is strictly limited in Japan and requires hospitalization. Because of strict regulations, severe lack of medical facilities for RIT has become one of the most important medical problems, which results in prolonged waiting time for Japanese patients with DTC, including those with distant metastasis, who wish to receive RIT immediately. This situation is also due to various other factors, such as prolonged economic recession, super-aging society, and subsequent rapidly changing medical environment. In addition, due to the experience of atomic bombings in Hiroshima and Nagasaki, Japanese people have strong feeling of "radiophobia". There is fear that GEJD and related radiation contamination may worsen this feeling, which might be reflected in more severe regulation of RIT. To overcome these difficulties, it is essential to collect and disclose all information about the circumstances around this therapy in Japan. In this review, we would like to look at this therapy through several lenses, including historical, cultural, medical, and socio-economic points of view. We believe that clarifying the problems is sure to lead to the resolution of this complicated situation. We have also included several recommendations for future improvements.

Practical management of well differentiated thyroid carcinoma in Korea

OBJECTIVES

The optimal extent of surgery and postoperative management of patients with well differentiated thyroid carcinoma (WDTC) vary among countries and institutions. We assessed the practical management of WDTC in Korea by questionnaire and compared these results with those obtained in similar surveys of members of the Japanese Society of Thyroid Surgery (JSTS) and the International Association of Endocrine Surgeons (IAES).

MATERIALS AND METHODS

Questionnaires were sent by mail or e-mail to 266 members of the Korean Association of Endocrine Surgeons (KAES). Ninety members (33.8%) completed the questionnaire; their responses were compared with those of the JSTS and IAES surveys.

RESULTS

Total thyroidectomy was more prevalent in the KAES and IAES than in the JSTS, irrespective of tumor size in the low-risk group. Patients with papillary microcarcinoma were more likely to undergo aggressive central compartment node dissection in the KAES than in the IAES or JSTS. Thyroid stimulating hormone suppression therapy was administered to a higher proportion of patients and for longer times in the KAES and IAES than in the JSTS. Postoperative radioactive iodine treatment was more prevalent in the KAES than in the JSTS. There were no differences between the KAES and the JSTS in the treatment of patients with locally advanced thyroid carcinoma. External irradiation and radioactive iodine treatment for recurrent papillary thyroid carcinoma were favored more by the KAES than the IAES and JSTS.

CONCLUSIONS

The actual practices of members of the KAES were almost similar to those of the IAES, but differed from those in Japan in some aspects. In general, however, members of the KAES favored more aggressive treatment of WDTC than did physicians in other countries.

Initial surgical management of thyroid cancer

The rapid increase in the rate of papillary thyroid cancer is likely caused by improved surveillance. A significant trend toward total thyroidectomy for low-risk differentiated thyroid cancer is present in the United States after a paradigm shift from treatment of macroscopic disease to the treatment of macroscopic and microscopic disease by increasingly sensitive tests. Compelling arguments for thyroid lobectomy and total thyroidectomy for low-risk thyroid cancer remain. The relatively small number of deaths from thyroid cancer, the small number of clinical thyroid cancers, and the huge number of incidental thyroid cancers are indicative of how little we understand the biology of this disease. Clinical medicine awaits biologic markers to refine treatment recommendations.

Clinical features and prognostic factors for survival in patients with poorly differentiated thyroid carcinoma and comparison to the patients with the aggressive variants of papillary thyroid carcinoma

We performed this study to compare the clinicopathologic features and outcomes between the patients with poorly differentiated thyroid carcinoma (PDTC) and the patients with the aggressive variants of papillary thyroid carcinoma (PTC). To evaluate the prognostic factors for survival of the patients with PDTC, we selected 49 patients with PDTC and 23 patients with the aggressive variants of PTC from three hospitals during the recent 15 years. The five-year survival rate and clinicopathologic features of the patients with PDTC were not different from those of the patients with the aggressive variants of PTC. Univariate analysis revealed the significant poor prognostic factors for survival of the patients with PDTC and the aggressive variants of PTC as follows: 1) an age more than 45 years, 2) a tumor size larger than 4 cm, 3) the presence of tumor invasion to extrathyroidal tissue or the trachea, 4) the presence of cervical lymph node invasion, 5) the presence of distant metastasis, 6) the absence of high-dose radioactive iodine (RAI) therapy, and 7) TNM stage II, III and IV. Distant metastasis and high-dose RAI therapy were independent significant predictors for survival of the patients with PDTC and the aggressive variants of PTC on multivariate analysis. However, distant metastasis was the only independent significant predictors for survival of the patients with PDTC excluding patients with the aggressive variants of PTC.

Unique treatment policy for well-differentiated thyroid cancer in Japan: results of a questionnaire distributed to members of the Japanese Society of Thyroid Surgery and the International Association of Endocrine Surgeons

Although surgery has been the mainstay of treatment for patients with well-differentiated thyroid cancer, the extents of thyroid resection and lymph node dissection adopted in Japan differ from those in other countries. Furthermore, regarding the indications for postoperative radiation therapy and hormonal therapy, and treatment modalities for cancer recurrence, there are marked discrepancies between Japan and other countries. A questionnaire survey was thus conducted among domestic and overseas thyroid surgeons to ascertain the actual treatment policy for well-differentiated thyroid cancer in Japan and various foreign countries. For small papillary carcinomas of 2.0 cm or less (T1), thyroid resection was more extensive in foreign countries than in Japan, although the extent of lymph node dissection was limited in the former. For large papillary carcinomas exceeding 3.0 cm (T2), on the other hand, total thyroidectomy was the treatment of first choice for all overseas respondents, but of only 20% in Japan, despite lymph node dissection being more extensive in Japan than in other countries. Overseas surgeons were much more likely to favor postoperative TSH suppression therapy and high-dose (131)I therapy. For recurrence following surgery for papillary thyroid cancer, both domestic and overseas respondents indicated surgical resection to be the most common treatment option, and favored high-dose (131)I therapy as well. In Japan, however, high-dose (131)I therapy is available only in a few institutions. Such limited indications for high-dose (131)I therapy in Japan may reflect a discrepancy in the frequency of total thyroidectomy, a prerequisite for postoperative high-dose (131)I therapy, between Japan and other countries. This is the first questionnaire study conducted in both Japan and other countries in relation to treatment modalities for thyroid cancer. The results reveal that there is a clear disparity in treatment policies between Japan and foreign countries.

Management of differentiated thyroid carcinoma with radioiodine and recombinant human TSH

Recombinant human TSH (rhTSH) brought revolutionary change in the management of patients with differentiated thyroid cancer since it was first approved for clinical use in the United States and Europe. Follow-up management of differentiated thyroid cancer is based on the detection of recurrent or residual cancer, traditionally achieved by measurement of serum thyroglobulin level and various imaging techniques including 131I whole body scan. Previously, TSH stimulation was achieved only by induction of hypothyroidism following withdrawal of thyroid hormone. However, hypothyroidism is uncomfortable and is association with a reduction in quality of life. RhTSH can provide elevated TSH without making patients hypothyroid. In the United States and Europe, rhTSH is approved for use only in monitoring of differentiated thyroid cancer. In this article, we reviewed the role of rhTSH in the diagnosis and management of differentiated thyroid cancer.

De novo multiple endocrine neoplasia type 2B with noncardiogenic pulmonary edema as the presenting symptom

Multiple endocrine neoplasia (MEN) type 2B is a rare hereditary disorder characterized by medullary thyroid carcinoma, pheochromocytoma, and neuroma. Early signs of MEN 2B are usually neuroma, gastrointestinal problems, and medullary thyroid carcinoma. Noncardiogenic pulmonary edema is rare as a presenting symptom. We report a 31-year-old male who was admitted to our hospital because of noncardiogenic pulmonary edema. He was 168 cm in height, weighed 55 kg, and had an arm span of 166 cm. No marfanoid habitus was evident, but thickened lips and tongue neuroma were present. Chronic constipation had been present since childhood, and the patient had a two-year history of untreated hypertension. Noncardiogenic pulmonary edema and toxic megacolon were noted, and abdominal computed tomography revealed bilateral adrenal tumors. Ultrasonography of the thyroid showed two mass lesions. Intubation and mechanical ventilation were performed because of severe hypoxemia. Endocrinological examinations showed high levels of serum and urinary fractionated catecholamines, serum calcitonin, serum carcinoembryonic antigen, and serum intact parathyroid hormone. It was suggested that the high level of catecholamine from pheochromocytoma had caused the pulmonary edema. RET gene analysis showed a codon 918 mutation in exon 16 resulting in an ATG (methionine) to ACG (threonine) substitution, but analysis of the patient's parents showed the wild type. Therefore, the patient was diagnosed as having de novo MEN 2B. He underwent laparoscopic bilateral adrenectomy and total thyroidectomy. However, the values of serum calcitonin and CEA did not decrease to the normal ranges. Patients with early-stage MEN 2B have distinct characteristics that can aid early detection of the disease, thus possibly allowing them to be saved.