Analyses of the outcome of locally invasive papillary thyroid carcinomas

Guideline for the Surgical Management of Locally Invasive Differentiated Thyroid Cancer From the Korean Society of Head and Neck Surgery

The aim of this study was to develop evidence-based recommendations for determining the surgical extent in patients with locally invasive differentiated thyroid cancer (DTC). Locally invasive DTC with gross extrathyroidal extension invading surrounding anatomical structures may lead to several functional deficits and poor oncological outcomes. At present, the optimal extent of surgery in locally invasive DTC remains a matter of debate, and there are no adequate guidelines. On October 8, 2021, four experts searched the PubMed, Embase, and Cochrane Library databases; the identified papers were reviewed by 39 experts in thyroid and head and neck surgery. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the quality of evidence, and to develop and report recommendations. The strength of a recommendation reflects the confidence of a guideline panel that the desirable effects of an intervention outweigh any undesirable effects, across all patients for whom the recommendation is applicable. After completing the draft guidelines, Delphi questionnaires were completed by members of the Korean Society of Head and Neck Surgery. Twenty-seven evidence-based recommendations were made for several factors, including the preoperative workup; surgical extent of thyroidectomy; surgery for cancer invading the strap muscles, recurrent laryngeal nerve, laryngeal framework, trachea, or esophagus; and surgery for patients with central and lateral cervical lymph node involvement. Evidence-based guidelines were devised to help clinicians make safer and more efficient clinical decisions for the optimal surgical treatment of patients with locally invasive DTC.

Surgical treatment of locally advanced thyroid cancer

Operations in this area are demanding and require special experience in endocrine, thoracic and vascular surgery, an experienced anaesthesiologist, as well as the interdisciplinary cooperation with other medical specialists (nuclear medicine, oncology, radiology, otolaryngology). A reliable system of surgical guidelines has been developed from a few individual publications with special impact.

Poorly differentiated thyroid carcinoma presenting with gross extrathyroidal extension: 1986-2009 Memorial Sloan-Kettering Cancer Center experience

PURPOSE

To describe the outcome of patients with poorly differentiated thyroid cancer (PDTC) presenting with gross extrathyroidal extension (ETE).

MATERIALS AND METHODS

After obtaining Institutional Review Board approval, we performed a retrospective review of a consecutive series of thyroid cancer patients treated by primary surgical resection with or without adjuvant therapy at Memorial Sloan-Kettering Cancer Center from 1986 to 2009. Out of 91 PDTC patients, 27 (30%) had gross ETE (T4a), and they formed the basis of our study. Of 27 patients, 52% were women. The median age was 70 years (range 27-87 years). Ten patients (37%) presented with distant metastases; four to bone, three to lung, and three to both bone and lung. All patients had extended total thyroidectomy, except two who had subtotal thyroidectomy. Twenty patients (74%) had central compartment neck dissection and 11 also had lateral neck dissection. Four patients had pN0, six (30%) pN1a, and 10 (50%) pN1b neck disease. Twenty-one patients (77%) had adjuvant therapy: 15 (55%) radioactive iodine (RAI) only, three (11%) postoperative external beam radiation (EBRT) only, and three (11%) had both RAI and EBRT. Overall survival (OS), disease-specific survival (DSS), local recurrence-free survival (LRFS), and regional recurrence-free survival (RRFS) were calculated by the Kaplan Meier method.

RESULTS

The median follow-up time was 57 months (range 1-197 months). The 5 year OS and DSS were 47% and 49%, respectively. This poor outcome was due to distant metastatic disease; 10 patients had distant metastases at presentation and a further six developed distant metastases during follow-up. Locoregional control was good with 5-year LRFS and RRFS of 70% and 62%, respectively. Overall, eight patients (30%) had recurrences: two had distant alone, two regional, two regional and distant, one local and distant, and one had local, regional, and distant recurrence.

CONCLUSION

Aggressive surgery in patients with PDTC showing gross ETE resulted in satisfactory locoregional control. Due to the small proportion of patients who received EBRT (22%), it is not possible to analyze its benefit on locoregional control. Of significance is the observation that the majority of patients (60%) who presented with or subsequently developed distant metastases eventually died of distant disease. New systemic therapies to target distant metastatic disease are required for improvements in outcome.

Prognosis and prognostic factors of patients with papillary carcinoma showing distant metastasis at surgery (M1 patients) in Japan

Distant metastasis (DM) at surgery is a prominent prognostic factor in patients with papillary carcinoma of the thyroid. However, the clinical outcomes of these patients (M1 patients) remain unclear. In this study, we investigated the prognosis and prognostic factors of M1 patients. Seventy-one of 5969 patients who underwent initial surgery in Kuma Hospital between 1987 and 2004 were classified as M1 and enrolled in this study. Five-year and 10-year cause specific survival (CSS) rates were 78.8 +/- 5.2% and 76.3 +/- 5.7%, respectively. Patients aged 55 years or older, having tumor larger than 4 cm, massive extrathyroid extension to adjacent organs other than the recurrent laryngeal nerve and cricothyroid or inferior constrictor muscle, and DM to organs other than the lung showed a significantly worse CSS on univariate analysis. On multivariate analysis, the first three parameters were recognized as independent prognostic factors for M1 patients. Patients who underwent locally curative surgery, having DM showing radioactive iodine (RAI) uptake, and who underwent thyroid stimulation hormone (TSH) suppression therapy showed a better CSS rates than those who underwent only palliative surgery, having DM without RAI uptake, and who did not undergo TSH suppression therapy, although there was no significant difference in CSS between these groups. These findings suggest that evaluation of preoperative and intra-operative findings is important to predict the prognosis of M1 patients, the same as that in patients without DM. Locally curative surgery, RAI therapy, and TSH suppression therapy are actively recommended for M1 patients when conditions permit.

Invasive thyroid cancer: management of the trachea and esophagus

Well-differentiated thyroid cancer most commonly presents as an intrathyroidal tumor; however, extrathyroidal extension occurs in approximately 6% to 13% of patients and carries a significant negative impact on survival. Extrathyroidal disease may involve critical structures in the central neck, including the recurrent laryngeal nerves, trachea, esophagus, and larynx, requiring surgery extending significantly beyond the thyroid gland. Appropriate surgical management is of great importance and can normalize survival curves, whereas gross residual disease postoperatively may lead to recurrence and decreased survival. Adjuvant postoperative therapies for thyroid cancers with extrathyroidal extension include thyroid hormone suppression, radioactive iodine therapy, and external beam radiotherapy. This summary reviews approaches to the management of invasive thyroid cancers involving the aerodigestive tract.

Papillary thyroid carcinoma with distant metastases: survival predictors and the importance of local control

BACKGROUND

The presence of distant metastases is the most important predictive factor of poor outcomes in patients with papillary thyroid carcinoma (PTC). Some patients have very slow-growing distant metastases with relatively favorable outcomes, so predicting prognosis is not easy. Furthermore, many patients with distant metastases show locally advanced disease, and no consensus is available for operative control of cervical tumor in this situation.

METHODS

Among 1023 patients with PTC who underwent primary thyroidectomy from 1976 to 2002, 42 patients displayed distant metastases at initial presentation and 44 patients developed distant metastases during follow-up. We reviewed the records retrospectively of these 86 patients. Mean duration of follow-up after detection of distant metastases was 7 years. Our treatment approach for patients with locally advanced neoplasms was radical resection including extensive neck dissection and extended resection of the involved organs, even when distant metastases were present.

RESULTS

Disease-specific survival of the 86 patients with distant metastases at 5 and 10 years was 65% and 45%, respectively. Using multivariate analysis, older age at time of distant metastases detection, distant metastases involving sites other than the lung, distant metastases diameter > or = 2 cm, presence of large nodal metastases (> or = 3 cm), and a primary neoplasm with poorly differentiated components were all predictive of worse prognosis. Our aggressive approach allowed curative resection in all but 1 patient, and only 5 patients (6%) succumbed to local disease. Patients with cervical recurrences displayed worse prognosis than those without.

CONCLUSIONS

Although the currently employed modalities of therapy for distant metastases do not have definitive impact on survival, some PTC patients with distant metastases, including younger patients with well-differentiated, small lung metastases appear to have relatively favorable outcomes. Local operative control of PTC is important even in patients with distant metastases, particularly when the distant metastases appear to be slow-growing.

Retrospective analysis of predictive factors for recurrence after curatively resected papillary thyroid carcinoma

PURPOSE

This retrospective study analyzes the predictive factors after curative surgery for papillary thyroid carcinoma (PTC).

METHODS

We analyzed 386 patients who underwent a curative operation for PTC in our hospital between 1977 and 1997, subject to the inclusion criteria.

RESULTS

According to univariate analysis, pathological lateral cervical lymph node involvement (P < 0.0001), dedifferentiation of the tumor (P < 0.002), male sex (P < 0.0001), a large tumor (P < 0.005), and an age of over 50 years (P < 0.05) were significant factors. Cox's proportional hazard model showed that a man (P < 0.05), aged over 50 years (P < 0.05), who had a large primary tumor (P < 0.05) with dedifferentiation (P < 0.05), and pathological lateral cervical lymph node metastasis (P < 0.005) was more likely to have recurrence of PTC.

CONCLUSIONS

Determining whether lymph node metastasis exists could be useful for predicting recurrence in patients who have undergone curative resection of PTC.

Management of the locally aggressive thyroid carcinoma

The management of locally advanced thyroid carcinoma can be challenging. Differing philosophies exist for the treatment of invasive disease affecting the upper aerodigestive tract. The ability to maximize local control and overall survival while minimizing the morbidity of a radical resection is the goal of care in these patients. This article will review the literature concerning the presentation, preoperative evaluation, and the subsite treatment of locally aggressive well-differentiated thyroid carcinoma.

Radioiodine or surgery for toxic thyroid adenoma: dissecting an important decision. A cost-effectiveness analysis

OBJECTIVE

To examine the cost effectiveness of therapeutic strategies for toxic thyroid adenoma.

DESIGN

Markov state transition decision analytic model.

SETTING

Ambulatory and inpatient.

PATIENTS

Hypothetical cohort of 40- year-old women with toxic thyroid adenomas. Patient age was varied in sensitivity analyses. Data on the prevalence of coincident thyroid cancer, complications, and treatment efficacies were derived from a systematic review of the literature.

INTERVENTIONS

Thyroid lobectomy after a 3 month-course of antithyroid drugs (ATDs), high-dose (<555 MBq) radioactive iodine (RAI), low-dose (>555 MBq) RAI, and lifelong ATDs.

MEASUREMENTS AND MAIN RESULTS

Outcomes were measured in quality-adjusted life years (QALYs). Costs were estimated from the health care system perspective. Future costs and effectiveness were discounted at 3% per year. For a 40- year-old woman, surgery was the most effective, while low-dose RAI was the least costly. The marginal cost-effectiveness of surgery versus low-dose RAI was $13,183 per QALY. Surgery was less costly and more effective than lifelong ATDs. RAI was more effective than surgery if surgical mortality exceeded 0.90% (base-case 0.001%). Surgery provided relatively inexpensive gains (<$50,000 per QALY) in quality-adjusted life expectancy in patients less than 74 years of age.

CONCLUSIONS

For most patients less than 60 years of age, surgery is an effective strategy with a reasonable cost. However, for any given patient, surgical mortality, therapeutic costs and preference must be considered in choosing an appropriate therapy.

Changes of expression level of the differentiation markers in papillary thyroid carcinoma under thyrotropin suppression therapy in vivo immunohistochemical detection of thyroglobulin, thyroid peroxidase, and thyrotropin receptor

BACKGROUND AND OBJECTIVES

Differences in the expression levels of Thyroglobulin (Tg), Thyroid peroxidase (TPO) and thyrotropin receptor (TSH-R) in primary and recurrent specimens under a suppressive serum TSH condition were elucidated in 26 papillary carcinoma patients.

METHODS

Immunohistochemical detection was performed by use of each monoclonal antibody against Tg, TPO, and TSH-R. The staining concentrations of the three markers in each specimen were measured for comparison.

RESULTS

The mean staining concentrations of Tg, TPO, and TSH-R in the entire primary tumor were 103.92, 104.6 and 89.25, respectively. Five cases showed stronger expression of all the differentiation markers and eight cases showed weaker expression of all these markers in recurrent tissue than in primary tumors. The weaker expression of TSH-R at the recurrent site as compared with that at the primary site significantly demonstrated the shortness of the disease free interval or overall survival. There were significant differences between the death due to cancer and the weaker expression of TSH-R in the recurrent tumor as compared with that in the primary tumor.

CONCLUSIONS

Under the TSH suppressive condition, the markers were not expressed uniformly among recurrent tumors. Even under that state, however, low expression of TSH-R in the recurrent tissue was strongly related to a poorer outcome in the patients.