Management of recurrent and persistent metastatic lymph nodes in well-differentiated thyroid cancer: a multifactorial decision-making guide for the Thyroid Cancer Care Collaborative.

BACKGROUND: Well-differentiated thyroid cancer (WDTC) recurs in up to 30% of patients. Guidelines from the American Thyroid Association (ATA) and the National Comprehensive Cancer Network (NCCN) provide valuable parameters for the management of recurrent disease, but fail to guide the clinician as to the multitude of factors that should be taken into account. The Thyroid Cancer Care Collaborative (TCCC) is a web-based repository of a patient's clinical information. Ten clinical decision-making modules (CDMMs) process this information and display individualized treatment recommendations. METHODS: We conducted a review of the literature and analysis of the management of patients with recurrent/persistent WDTC. RESULTS: Surgery remains the most common treatment in recurrent/persistent WDTC and can be performed with limited morbidity in experienced hands. However, careful observation may be the recommended course in select patients. Reoperation yields biochemical remission rates between 21% and 66%. There is a reported 1.2% incidence of permanent unexpected nerve paralysis and a 3.5% incidence of permanent hypoparathyroidism. External beam radiotherapy and percutaneous ethanol ablation have been reported as therapeutic alternatives. Radioactive iodine as a primary therapy has been reported previously for metastatic lymph nodes, but is currently advocated by the ATA as an adjuvant to surgery. CONCLUSION: The management of recurrent lymph nodes is a multifactorial decision and is best determined by a multidisciplinary team. The CDMMs allow for easy adoption of contemporary knowledge, making this information accessible to both patient and clinician.

Medical therapy for advanced forms of thyroid cancer.

More options than ever before are currently available for medical therapy in patients who present with advanced thyroid cancer or develop surgically unresectable recurrences or symptomatic or progressive disease. The newer medical therapies have addressed the need to find effective therapies beyond the conventional treatment with radioactive iodine, thyroid stimulating hormone suppression, and palliative cytotoxic chemotherapy for patients with advanced thyroid cancer. Although tumor responses to these medical therapies vary by type of thyroid cancer and type of therapy selected, they remain encouraging and provide therapeutic options for selected patients while new drugs are in development.

Falsely low parathyroid hormone secondary to biotin interference: a case series.

OBJECTIVE: To present a case series on biotin interference in parathyroid hormone (PTH) level measurement. METHODS: We review the presentation and management of patients at our institution evaluated for unexpectedly low PTH levels while taking biotin supplements in the setting of high or normal serum calcium. RESULTS: Two patients presented with surprising low parathyroid levels--one during preoperative evaluation for hyperparathyroidism and another during postoperative follow-up after subtotal parathyroidectomy. The patients were found to be taking 1,500 mcg and 5,000 mcg of biotin per day, respectively. The role of biotin interference was confirmed in one of the patients when she was retested off biotin, and PTH levels responded appropriately. Biotin supplements remain as unbound molecules in the serum, thus interfering with PTH enzyme-linked immunosorbent assay (ELISA) results and falsely depressing the PTH level. CONCLUSION: Biotin supplement use has expanded over the years, ranging from medically endorsed therapies to home remedies. Review of the 2 ELISA systems used at our institution demonstrates that free biotin mimics the biotinylated antibody used in the detection process. Screening for biotin use prior to PTH measurement and automatic biotin levels for clinically aberrant PTH levels provide the clinician with a true PTH level--lowering the disease burden of untreated hyperparathyroidism while avoiding unnecessary work-ups for other processes.

The use of the harmonic scalpel versus knot tying for modified radical neck dissection.

BACKGROUND: Although the utility of the harmonic scalpel (HS) in thyroidectomy has been extensively demonstrated, there is little experience regarding its use for neck dissections. METHODS: Within 10 years, 119 patients underwent modified radical neck dissection (MRND) for thyroid cancer. In 51 patients, MRND was performed using conventional knot tying and in 68 using the HS. The number of lymph nodes (LNs) removed, operative time, estimated blood loss (EBL), drain output, duration of the drainage, and complications were compared for 47 patients undergoing first-time unilateral MRND without concomitant additional surgical procedures. RESULTS: The number of LNs removed, operative time, duration of drainage, and rate of lymphatic leak were similar between groups. For the HS group, EBL (5 ± 3 vs 32 ± 10; P = .006) and drain output on postoperative day 1 (51.7 ± 6.2 vs 78.9 ± 11.9; P = .02) and at 1 week (6.1 ± 1.2 vs 10.2 ± 1.8, respectively; P = .03) were significantly less. CONCLUSION: Despite the limitations of its retrospective nature, this study shows that the HS reduces EBL and the amount of lymphatic drainage compared to knot tying after MRND.

Radiation safety in the treatment of patients with thyroid diseases by radioiodine 131I : practice recommendations of the American Thyroid Association.

BACKGROUND: Radiation safety is an essential component in the treatment of patients with thyroid diseases by ¹³¹I. The American Thyroid Association created a task force to develop recommendations that would inform medical professionals about attainment of radiation safety for patients, family members, and the public. The task force was constituted so as to obtain advice, experience, and methods from relevant medical specialties and disciplines. METHODS: Reviews of Nuclear Regulatory Commission regulations and International Commission on Radiological Protection [corrected] recommendations formed the basic structure of the recommendations. Members of the task force contributed both ideas and methods that are used at their respective institutions to aid groups responsible for treatments and that instruct patients and caregivers in the attainment of radiation safety. There are insufficient data on long-term outcomes to create evidence-based guidelines. RESULTS: The information was used to compile delineations of radiation safety. Factors and situations that govern implementation of safety practices are cited and discussed. Examples of the development of tables to ascertain the number of hours or days (24-hour cycles) of radiation precaution appropriate for individual patients treated with ¹³¹I for hyperthyroidism and thyroid cancer have been provided. Reminders in the form of a checklist are presented to assist in assessing patients while taking into account individual circumstances that would bear on radiation safety. Information is presented to supplement the treating physician's advice to patients and caregivers on precautions to be adopted within and outside the home. CONCLUSION: Recommendations, complying with Nuclear Regulatory Commission regulations and consistent with guidelines promulgated by the National Council on Radiation Protection and Measurement (NCRP-155), can help physicians and patients maintain radiation safety after treatment with ¹³¹I of patients with thyroid diseases. Both treating physicians and patients must be informed if radiation safety, an integral part of therapy with ¹³¹I, is to be attained. Based on current regulations and understanding of radiation exposures, recommendations have been made to guide physicians and patients in safe practices after treatment with radioactive iodine.

Normalization of 2-week postoperative parathyroid hormone values in patients with primary hyperparathyroidism: four-gland exploration compared to focused-approach surgery.

BACKGROUND: Elevation of parathyroid hormone (PTH) levels is commonly seen in patients with primary hyperparathyroidism (PHPT) who have undergone parathyroidectomy. This study evaluates differences in 2-week postoperative PTH levels in patients having focused-approach surgery versus four-gland exploration. METHODS: Over 6 years, patients at Rhode Island Hospital (RIH) and the Cleveland Clinic (CCF) who had PHPT and underwent localization studies suggestive of single adenoma were analyzed. At RIH patients underwent focused-approach surgery, and at CCF routine four-gland exploration was performed. Postoperative calcium supplementation was routine at RIH and selective at CCF. RESULTS: There were 308 patients at RIH and 370 at CCF. They were similar in age (59.2 +/- 13.0 years at RIH and 60.4 +/- 12.9 years at CCF), and sex (76.9 and 80.0% female at RIH and CCF, respectively). The mean preoperative serum calcium measured 10.9 +/- 0.7 mg/dl at RIH and 11.1 +/- 0.7 mg/dl at CCF (P < 0.001). Preoperative PTH values were similar, measuring 143.8 +/- 104.8 pg/ml in the focused-approach group (RIH) and 157.6 +/- 150.3 pg/ml in the four-gland exploration group (CCF). Preoperative 25-hydroxyvitamin D (vitamin D-25) levels were 24.1 +/- 12.0 ng/ml at RIH and 27.4 +/- 10.6 ng/ml at CCF; and the prevalence of vitamin D-25 deficiency (level <20 ng/ml) was 43.9% at RIH and 27% at CCF (P = 0.017). The proportion of patients whose intraoperative PTH value dropped by >or=50% prior to completion of surgery was 95.0% at RIH and 95.5% at CCF. The total gland weight resected per patient was 942 mg at RIH versus 1,394 mg at CCF (P = 0.003). The 2-week postoperative serum PTH was >65 pg/ml in 18.8% at RIH and in 38.7% at CCF (P < 0.001). The 2-week postoperative serum calcium values dropped to 9.2 +/- 0.6 mg/dl at RIH and to 9.5 +/- 0.8 mg/dl at CCF (P < 0.001). The incidence of multigland disease was 5.8% at RIH and 21.9% at CCF (P